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Your Heart and Nutrition

Your Heart and Nutrition

Prevention is better than a cure. Learn how to cherish your heart by taking the necessary means to keep it pumping healthily and steadily through your life.

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Natural Secrets For Healing Your Heart

This eBook is devoted to exposing the secrets that cardiologists and surgeons don't want you to know, and how to take control of your own heart and heal yourself. Eight out of every ten coronary bypasses will not actually help the patient. So why risk being in the 80% that will get no benefit from a bypass? Learn to heal your own heart and keep yourself healthy with this eBook guide. Bob Livingston has poured years of research into his findings, and is now sharing the methods that he has developed from careful, methodical research that the medical industry would never allow. It would make them go bankrupt! You will learn what supernutrient doctors don't want you to know about, and how to make an all-natural, chemical and drug-free blood thinner And even more information that doctors don't want revealed to the public. You don't have to be one of the 70% of Americans diagnosed with heart disease. You can heal your heart!

Natural Secrets For Healing Your Heart Overview

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Cardiovascular Disease

Cardiovascular disease (CVD) has been for many years the leading single cause of death in the United States (14) it includes both coronary heart disease (CHD) and stroke. CHD is the most common form of cardiovascular disease. In 1987 nearly 1 million deaths in the United States, half of the total number, occurred due to some form of CVD (15). In 1998, CVD remains the leading cause of death in the United States (14), although there have been some reductions in the rate. Cardiovascular disease is often thought to affect mainly men and the elderly, but it is also a major killer of women and people in the prime of life (14). An estimated 58 million Americans live with some form of the disease, and almost 10 million Americans aged 65 years and older report disabilities caused by heart disease. Stroke is also a leading cause of disability in the United States, affecting more than 1 million people nationwide (14). The health burden of this condition is rivaled by the economic burden, which...

Role Of Diet In Cardiovascular Disease

Improper eating habits accompanied by the lack of exercise increase the risk of gaining excess weight, a major risk factor for heart disease, high blood pressure, and diabetes (14). Diet also affects plasma cholesterol levels. Cholesterol is carried in the blood associated with two major types of lipoproteins LDL and HDL. LDL cholesterol has been Table 7. Major Risk Factors for Cardiovascular Disease correlated with increased risk of cardiovascular disease. For many years it has been recognized that dietary cholesterol has only a limited effect on plasma cholesterol levels (17). Absorption of ingested cholesterol is poor, and part of the cholesterol in plasma is synthesized in the liver. High levels of dietary carbohydrate, especially complex carbohydrate, are associated with a decreased risk of cardiovascular disease (17). A recent study found rice bran as well as oat bran to have a hypocholesterolemic effect (26). Increasing intakes of a number of vitamins have also been shown to be...

Acute myocardial infarction

30 Acute non-ST-segment elevation coronary syndromes unstable angina and 397 non-ST-segment elevation myocardial infarction 32 Mechanical reperfusion strategies in patients presenting with acute myocardial infarction 444 Sanjaya Khanal, W Douglas Weaver 33 Adjunctive antithrombotic therapy for ST-elevation acute myocardial infarction 456 John K French, Harvey D White 35 Complications after myocardial infarction 488 Peter L Thompson, Barry McKeown 36 An integrated approach to the management of patients after the early 507 phase of the acute coronary syndromes Part IIIc Specific cardiovascular disorders Atrial fibrillation and 517

Benefits Coronary Heart Disease

A large number of investigators have studied the relation between alcohol intake and coronary heart disease. Studies indicate that the descending leg of the curve is mainly attributable to death from coronary heart disease, as mentioned previously. The lowest risk seems to be among subjects reporting an average intake of one to four drinks daily. Several studies have found plausible mechanisms for the apparent cardioprotective effect of a light to moderate intake of alcohol. Subjects with a high alcohol intake have a higher level of high-density lipopro-tein, which has been found to be a mediator of the effect of alcohol on coronary heart disease. Thus, 40-60 of the effect of alcohol on coronary heart disease is likely to be attributable to the effect on high-density lipoprotein. Furthermore, drinkers have a lower low-density lipoprotein. Also, alcohol has a beneficial effect on platelet aggregation, and thrombin level in blood is higher among drinkers than among nondrinkers....

Ischaemic Heart Disease IHD

In the UK 12-20 of patients undergoing surgery have pre-operative evidence of myocardial disease. This is almost always due to atheroma although rarely other disease processes may be responsible. With increasing age atheromatous plaques form in the intima of arteries. These plaques grow and evolve with time, decreasing blood flow through a vessel and possibly occluding it. The rate of progression of individual plaques within any patient is variable and explains why although peripheral vascular and cerebrovascular disease will often co-exist with coronary artery disease, the patient may be asymptomatic of these other conditions. IHD may be diagnosed from a history of angina or myocardial infarction (MI). It may also be the underlying cause of a conduction defect or arrhythmia. A guide to the severity of angina is the exertion necessary to precipitate an attack. The distance that is regularly walked on the flat before an attack occurs should be elicited in the history. It may be that...

Acute coronary syndromes

Acute coronary syndromes include unstable angina, non-ST-segment elevation MI (NSTE MI) and ST-segment elevation MI (STE MI) (Santiago and Tadros, 2002). It is acknowledged that with revised definition of myocardial infarction, diagnosed by cardiac troponin estimation, there will be a resultant increase in the reporting of myocardial infarction, with increased workloads for the services involved (Dalal, et al, 2004). In the Cochrane systematic review by Jolliffe, et al. (2004) the reviewers concluded that exercise-based CR is effective in reducing cardiac deaths and has many positive health-related outcomes for post-MI and CHD groups.

Overall outcome in unstable anginanonST elevation myocardial infarction

Based upon prospective international registry data among 8000 patients in six countries, the risk of death or myocardial infarction is approximately 10 at six months and almost a quarter of patients sustain these events or acute refractory angina within six months of initial presentation (OASIS registry).2 Overall, half of these events occur within the first seven days of presentation. Based on those included in clinical trials, and excluding those with normal ECGs, about 10 suffer death or myocardial infarction at 30 days (GUSTO II data).3 These events occur despite aspirin treatment and antianginal medications. Recent data from the PRAISE UK registry indicate rates of death myocardial infarction of 12.2 at six months.4

Acute myocardial infarction primary angioplasty

The treatment of myocardial infarction has evolved considerably over the past decades. Reported mortality rates have fallen as a result of a variety of factors, including earlier diagnosis and treatment of the acute event, improved management of complications such as recurrent ischaemia and heart failure, and general availability of pharmacological treatments such as aspirin, P blockers, and angiotensin converting enzyme inhibitors.1 Most attention, however, has been focused on treatments that may restore antegrade coronary blood flow in the culprit artery of the patient with evolving acute myocardial infarction. The two methods to achieve this goal are thrombolytic treatment and immediate coronary angiography followed by primary angio-plasty if appropriate.1 History of angioplasty for acute myocardial infarction Angioplasty for acute myocardial infarction was first described as a rescue treatment in the case of failed intracoronary thrombolysis, and was studied extensively as...

Congenital heart disease

The patient group includes children and young people. Exercise and physical activity levels are dependent on the differing types of congenital heart disease. There may be barriers to exercise in this group, such as current symptoms, lack of interest in exercise and health fears (Swan and Hillis, 2000). A review by Brugemann, et al. (2004) found that patients with congenital heart disease should be included in multidisciplinary CR. In addition, physical training was found to be safe. A pre-training exercise test is required to determine specific and appropriate physical workload. Furthermore, education, psycho-social support and coping strategies to help reduce anxiety are essential parts of CR for this patient group. Paediatric specialists have advocated exercise-training programmes for children with congenital heart disease. A review of literature by Imms (2004) suggests that CR programmes for children should also promote occupational performance activity and integrate exercise into...

Acute myocardial infarction failed thrombolysis

Reperfusion strategies in the early phase of treatment of acute myocardial infarction aim to rapidly normalise and maintain tissue perfusion. Primary angioplasty is probably the best current treatment but it can only be applied to a minority of patients and has its own problems. Thrombolysis remains the most commonly used treatment. It has well demonstrated benefits, saving lives and reducing left ventricular damage, but is far from perfect.1 The mega-trials have sent a clear message that the greatest benefits are seen with patients who are treated early. Clinical efforts have therefore been concentrated on educating the population to heed the early symptoms, encouraging rapid admission to hospital (sometimes with thrombolytic treatment being administered in the ambulance) and minimising door to needle times. Continuous and widespread use of audit increases the number of patients treated and the speed with which treatment is administered. Measurement of cardiac enzyme release has...

Angiotensin receptor blockers for chronic heart failure and acute myocardial infarction

The question arises, therefore, as to what the role of the newest agents available for RAAS inhibition, the angiotensin II receptor antagonists or blockers (ARBs), might be in CHF and acute myocardial infarction A number of other key randomised, controlled, trials have also shown that ACE inhibitors reduce the risk of all cause mortality and major clinical events (sudden death, reinfarction, heart failure) after myocardial infarction.w1-3 These benefits are most clearly seen in patients with left ventricular systolic dysfunction or clinical evidence of heart failure.w4 LVEF, left ventricular ejection fraction NYHA, New York Heart Association ACE-I, angiotensin converting enzyme IHD, ischaemic heart disease LVIDD, left ventricular internal dimension. SOLVD-T Treatment arm of the Studies Of Left Ventricular Dysfunction SPICE Study of Patients Intolerant of Converting Enzyme Inhibitors STRETCH Symptom, Tolerability, Response to Exercise Trial of Candesartan cilexetil in Heart failure...

TABLE 475 Electrocardiographic Criteria for Acute Myocardial Infarction

Reciprocal ST-segment changes (such as ST-segment depressions in the anterior precordial leads in the setting of an inferior wall AMI) predict a larger infarct distribution, an increased severity of underlying coronary artery disease, more severe pump failure, a higher likelihood of cardiovascular complications, and increased mortality. In general, the more elevated the ST segments and the more ST segments that are elevated, the more extensive the injury. The ECG can also be used to predict the infarct-related vessel. Inferior wall myocardial infarctions can result from occlusion of the left circumflex artery or the right coronary artery. In the setting of an inferior wall AMI, ST-segment elevation in at least one lateral lead (V 5, V6, or aVL) with an isoelectric or elevated ST segment in lead I is strongly suggestive of a left circumflex lesion. The presence of ST-segment elevation in lead III greater than that in lead II predicts a right coronary artery occlusion. When accompanied...

Complications Of Myocardial Infarction And Ischemia

Myocardial perfusion and cardiac function affect blood flow to the entire body. As a result, any end organ can be damaged when cardiac pump function is decreased. In this section, discussion of the complications of acute coronary syndromes is limited to the direct effects on the heart. The systemic effects of cardiac function are discussed in organ-appropriate chapters of this book. The treatment of these complications is discussed in the following chapter. The genesis, diagnosis, and treatment of dysrhythmias are presented in Chap 24. The effect dysrhythmias have in complicating the course of patients with acute coronary syndromes is the subject of this section.

TABLE 478 Frequency of Occurrence of Arrhythmias during Acute Myocardial Infarction

Early in the course of AMI, patients frequently exhibit evidence of increased autonomic nervous system activity. Sinus bradycardia, atrioventricular block, and hypotension may occur from increased vagal tone. Activation of atrial and ventricular receptors in the myocardium may result in enhanced efferent sympathetic activity, increased circulating catecholamines, and increased local catecholamine release. These increased catecholamines in the setting of a sensitive myocardium form the substrate for the generation of tachyarrhythmias. Electrical instability during acute myocardial infarction results in ventricular premature beats, ventricular tachycardia, ventricular fibrillation, accelerated idioventricular rhythms, and some AV junctional tachycardias. The significance of cardiac dysrhythmias during acute myocardial infarction is the subject of some debate. Sinus bradycardia during the early phases of AMI may predispose to hypotension and repetitive ventricular dysrhythmias. On the...

TABLE 4711 Likelihood of Significant Coronary Artery Disease in Patients with Symptoms Suggesting Unstable Angina

Patients at high risk of coronary artery disease, AMI, or death should be admitted to an intensive care unit (ICU). Moderate risk patients should be admitted to a non-ICU monitored setting. Patients at low risk can be treated in a non-ICU monitored setting or can be observed in an ED observation unit. Both ED observation units and non-ICU monitored settings are safe and cost-effective for patients with normal ECGs and other low-risk clinical features. Prior invasive and noninvasive assessments of cardiac function should be taken into account in making disposition decisions. Patients known to have severe coronary artery disease or depressed left ventricular function might be triaged to a more intensive setting than patients with a similar presentation without such dysfunction. Results of prior cardiac catheterization are very useful for risk stratification. Patients who have previously been documented to have minimal (less than 25 percent) stenosis or normal coronary arteriograms have...

The declining mortality from coronary heart disease

There is no doubt that mortality from coronary heart disease is falling. Figure 6.410 shows that age specific mortality for males aged 35-44 years during 1997 was about one third, and of those aged 65-74 years about two thirds of the figures for 1968 when the coronary epidemic was at its height. Age groups 45-54 and 55-64 showed intermediate changes and the picture was similar in women. Data in fig 4 stop at age 75, however. If evidence from death certificates is to be believed, more than 60 of coronary deaths occur in people aged > 75 years.10 Death is being postponed, not prevented it has been estimated that the global burden of coronary heart disease will continue to increase up to the year 2020.11 Although the incidence of new events is falling, the prevalence of coronary heart disease in the community is increasing.10 For the hospital clinician there is much less difficulty in the definition of acute myocardial infarction. Most clinicians will accept that infarction should be...

Indications for PCI in chronic coronary artery disease

The indications for PCI have expanded during the past two decades, and no absolute contraindications remain (table 8.3). Single vessel coronary artery disease (CAD) remains the principal indication for PCI, with over 80 w74 of procedures performed in Europe and over 90 in the USA. This exponential growth of PCI has been largely at the expense of medical treatment rather than surgical revascularisa-tion. Beside clinical and angiographic factors, operator volume has been recognised as a major determinant ofoutcome in several recent studies.w75-78 There is no upper patient age limit to the applicability of PCI however, the threshold is shifted in favour of PCI compared with CABG in the very elderly owing to the higher perioperative morbidity and mortality in this patient population. Initial concerns of a sex difference in the outcome of PCI with women, There are no differences in death or myocardial infarction between patients undergoing PCI compared with CABG. Patients undergoing PCI...

Myocardial Infarction and Unstable Angina

Diagnosis Rule out myocardial infarction 3 Condition -Heparin 70 U kg IV push, then 15-17 U kg hr by continuous IV infusion for 48 hours to maintain aPTT of 50-70 seconds. Check aPTTq6h x 4, then qd. Repeat aPTT 6 hours after each heparin dosage change. Glycoprotein IIb IIIa Blockers for Acute Coronary Syndromes Absolute Contraindications to Thrombolytics Active internal bleeding, history of hemorrhagic stroke, head trauma, pregnancy, surgery within 2 wk, recent non-compressible vascular puncture, uncontrolled hypertension (> 180 110 mmHg).

Stroke Risk Factors

Stroke risk factors are very well understood. Both modifiable and nonmodifiable risk factors are important. The nonmodifiable stroke risk factors are age, ethnicity, and sex. There are several modifiable stroke risk factors, including hypertension, hypotension, diabetes, atrial fibrillation, congestive heart failure, coronary artery disease, smoking, hyperlipidemia, The most important modifiable stroke risk factor, hypertension, is estimated to affect approximately 50 million Americans (23 of the U.S. population), or 44 of Americans at least 65 years of age. Approximately one-third of all strokes directly relate to the impact of hypertension. Hypertension increases the risk of stroke up to 400 the relative risk of stroke among persons with hypertension is four times higher than that among individuals lacking this risk factor. As many as 246,500 strokes might be prevented by eliminating the adverse impact of hypertension (i.e., 35 of 700,000 annual strokes). The odds that a person with...

Studies on the Role of Exercise Fitness in the Etiology of Coronary Heart Disease

Coronary heart disease (CHD) has a multifactorial etiology, and major 'biological' risk factors include elevated concentrations of blood total and low-density lipoprotein (LDL) cholesterol, reduced concentration of high-density lipoprotein (HDL) cholesterol, high blood pressure, diabetes mellitus, and obesity. In addition, 'behavioral' risk factors for CHD include cigarette smoking, a poor diet, and low levels of physical activity and physical fitness associated with the modern, predominantly sedentary way of living. Among these risk factors, a sedentary lifestyle is by far the most prevalent according to data from both the United States and England (Figure 1).

S Pediatric Heart Disease

Assessment of, Children,, Suspected, ofMaving, Heart Disease Pediatric cardiovascular disorders are decidedly uncommon in emergency medicine. The incidence of congenital heart disease is only about eight cases per 1000 live births and contrasts sharply with the increasing prevalence of cardiovascular disease in adult populations. 1 Because of the relative unfamiliarity of such disorders, most emergency medicine physicians have encountered these disorders only in their initial training. The combination of the low incidence and the age-related differences in clinical presentation make timely recognition, stabilization, and appropriate tertiary referral a challenge for primary care physicians. In the emergency department, problems may range from an asymptomatic discovery of a murmur to the life-threatening presentation of a cyanotic infant in cardiogenic shock. Congenital heart disease is usually classified based on physiology (presence or absence of cyanosis, with or without persistent...

TABLE 11S1 Clinical Presentation of Pediatric Heart Disease

Children with previously undiagnosed heart disease can be broadly classified into three categories unstable, stable but symptomatic, and stable and asymptomatic. Unstable infants usually require immediate and decisive stabilization and aggressive management before diagnostic studies or tertiary referral can be made. Pediatric cardiology consultation should be emergently sought from the regional tertiary care center before pharmacologic intervention, if at all possible. Stable and symptomatic infants require less aggressive measures, so there is time to focus on physiologic derangement and correction of abnormalities of oxygenation and metabolism and time for tertiary referral. A baseline electrocardiogram (ECG) and chest radiograph are indicated in such infants particularly when a murmur appears to be pathologic (grade 3 or louder, holosystolic or diastolic in timing, and or radiating away from the heart). Stable but asymptomatic infants can easily be referred routinely based on...

Assessment Of Children Suspected Of Having Heart Disease

The physical examination of children with significant congenital heart disease is often not as dramatic as the diagnosis of congestive heart failure in adolescents. In the author's experience, unrecognized congenital heart disease in small infants is often not diagnosed until the second or third visit to the emergency department for the same illness. Most often, that illness is misdiagnosed as a viral upper respiratory illness or a feeding intolerance.

Coronary Heart Disease

Most epidemiologic studies and clinical trials using n-3 fatty acids in the form of fish or fish oil have been carried out in patients with coronary heart disease. However, studies have also been carried out on the effects of ALA in normal subjects and in patients with myocardial infarction. Another important consideration is the finding that during chronic fish oil feeding postprandial triacylgly-cerol concentrations decrease. Furthermore, consumption of high amounts of fish oil blunted the expected rise in plasma cholesterol concentrations in humans. These findings are consistent with the low rate of coronary heart disease found in fish-eating populations. Studies in humans have shown that fish oils reduce the rate of hepatic secretion of very low-density lipoprotein (VLDL) triacylglycerol. In normolipidemic subjects, n-3 fatty acids prevent and rapidly reverse carbohydrate-induced hypertriglyceridemia. There is also evidence from kinetic studies that fish oil increases the...

Endothelial Function Atherosclerosis and Cardiovascular Disease

Differences in n-6 fatty acid intake have the potential to influence several chronic diseases and disorders. This article will focus on the effects of n-6 fatty acids on cardiovascular disease and atherosclerosis. Atherosclerosis is an inflammatory disease involving multiple cellular and molecular responses that lead to an alteration in vascular function and structure, and the development and progression of cardiovascular disease. Atherosclerosis is characterized by degenerative changes, deposition of cholesterol, proliferation of smooth muscle cells, involvement of a range of circulating proinflamma-tory cell types, and fibrosis. Resulting atheromatous plaques cause narrowing of arteries and increase the likelihood of thrombosis and occlusion. When this process occurs in the coronary arteries, the outcome is myocardial infarction and with possible death.

Viral Infections with Congenital Heart Disease

Although few normal children have problems with common viral pathogens such as influenza virus, parainfluenza virus, or respiratory syncytial virus, children with congenital heart disease are at unique risk for major sequelae. Distinguishing minor early infections with these agents and differentiating them from the symptoms of congestive heart failure is a challenge, even for seasoned clinicians. Children with lesions that increase pulmonary blood flow are far more at risk because of pooling of alveolar secretions. The pooled secretions allow for stasis and secondary bacterial overgrowth. Dramatic increases in mortality and morbidity are evident among affected infants. No effective therapy is available for parainfluenza and influenza virus, and prophylaxis against influenza B with amantadine analogues is not approved for small children. Hospitalization and specific treatment of infants affected by respiratory syncytial virus has been difficult to justify due to conflicting studies...

Developmental Origins of Cardiovascular Disease Type 2 Diabetes and Obesity in Humans

Fetal Origins Adult Disease

Fetal growth restriction and low weight gain in infancy are associated with an increased risk of adult cardiovascular disease, type 2 diabetes and the Metabolic Syndrome. The fetal origins of adult disease hypothesis proposes that these associations reflect permanent changes in metabolism, body composition and tissue structure caused by undernutrition during critical periods of early development. An alternative hypothesis is that both small size at birth and later disease have a common genetic aetiology. These two hypotheses are not mutually exclusive. In addition to low birthweight, fetal 'overnutrition caused by maternal obesity and gestational diabetes leads to an increased risk of later obesity and type 2 diabetes. There is consistent evidence that accelerated BMI gain during childhood, and adult obesity, are additional risk factors for cardiovascular disease and diabetes. These effects are exaggerated in people of low birthweight. Poor fetal and infant growth combined with recent...

Risk of cardiovascular disease in patients with diabetes

As noted above, diabetes is an independent risk factor for cardiovascular disease.2 People with diabetes have a two- to fourfold higher risk of coronary, cerebrovascular, and peripheral vascular disease than non-diabetic people.1 The relative risk is greater for women than for men.1,19 Diabetes is also a poor prognostic factor post myocardial infarction (MI) diabetic patients have a higher inhospital mortality, and postdischarge mortality than non-diabetic patients, and a higher risk of infarct-related complications.20,21 Just as the risk of eye, kidney, and nerve disease increases with the degree of glycemia, a growing number of studies of diabetic patients suggest that the risk of cardiovascular disease also rises with the degree of glycemia. For example, the Wisconsin Epidemiologic Study of Diabetic Retinopathy followed a population-based sample of 1210 patients with diabetes presenting before the age of 30 and 1780 patients with diabetes presenting at or after the age of 30.22 In...

Glucose levels and the risk for cardiovascular disease in nondiabetic patients

Many prospective studies have consistently showed that the relationship between glucose levels and the subsequent risk of cardiovascular disease extends well below the diabetic threshold. For example, after 10 years of follow up in the Whitehall study of 18050 non-diabetic male civil servants, there was up to a twofold increase in coronary heart disease and stroke mortality in subjects whose 2 hour postload capillary glucose value was greater than 5-4 mmol l compared to those with lower glucose levels. This increase was independent of age, smoking, blood pressure, cholesterol, and occupation.26,27 The relationship of non-diabetic-range hyperglycemia and cardiovascular disease was also clearly noted after 14 years in the Rancho Bernardo study.28 In this prospective study of 3458 non-diabetic men and women aged 40-70 with a fasting plasma glucose < 7-8 mmol l, the age-adjusted ischemic heart disease mortality rates approximately doubled in men as the fasting glucose rose from 5 to 7...

Mechanisms relating hyperglycemia to cardiovascular disease

Possible explanations for a glucose-cardiovascular disease relationship include an association of dysglycemia with other recognized and unrecognized risk factors for cardiovascular disease, including dyslipidemia, hypertension, abdominal obesity, renal damage, and coagulation abnormalities.

Finding Genes for Cardiovascular Disease

Genetics studies of cardiovascular disease involve searches for genes in two general classes causative genes and disease-susceptibility (or disease-modifying) genes. These are sought through gene-linkage analysis or candidate-gene studies, respectively. Identifying causative genes for this disease is likely several years away at best. Before that time, however, a new understanding will have been reached regarding the relationship between inherited risks and outcomes in cardiovascular disease. With the development of new technology, we also have the promise of a detailed catalogue of disease-modifying genes that may open the door to therapeutic advances. Gene-linkage analyses involve the study of families that express the cardiovascular trait of interest. In such studies, it is important also to establish the relative risk. Relative risk is defined as the probability of developing a condition (such as cardiovascular disease) if a risk factor (such as a gene) is present, divided by the...

Myocardial scarring secondary to coronary artery disease

The risk of ventricular arrhythmia both near and distant to myocardial infarction is well established. Myocardial re-entry is allowed by the complex interaction of viable myocardium with scarred myocardium in and around infarct territories. These patients represent the majority of patients presenting with ventricular arrhythmias. Antiarrhythmic drug treatment may have a role in suppressing arrhythmia occurrence and thereby reduce the morbidity of such arrhythmias, but the data to support protection from SCD are increasingly weak.12 71617 Most such patients will therefore receive device therapy. However, while ICD therapy may be effective in reducing SCD risk, patients may have an unacceptable morbidity related to either frequency of antitachycardia pacing or delivery of defibrillating shock therapy. In this circumstance adjunctive ablation treatment may reduce this burden. Because such arrhythmias are frequently haemody-namically poorly tolerated, use of novel mapping techniques for...

Sudden death in children with postoperative congenital heart disease

In the 1960s and 1970s sudden cardiac death most often occurred in children with irreversible pulmonary vascular disease associated with unoperated congenital heart disease or in children with unoperated aortic valve stenosis.w8 w9 In recent years surgical repair has been performed earlier and more effectively so that those most at risk of sudden death now are children with repaired heart disease. In a population based study of late postoperative sudden death, Silka and colleagues identified an average risk of 0.9 per 1000 patient-years follow up for the most common surgically repaired malformations.7 Those patients with a risk above the average had aortic valve stenosis, transposition of the great arteries, tetralogy of Fallot or coarctation of the aorta. Death was attributed to arrhythmia in the majority, based on the history, but in only a few was an arrhythmia identified in life.

Frequency of coronary artery disease in patients with calcified aortic stenosis

The frequency of coronary artery disease in patients with calcified aortic stenosis can be correctly assessed only in studies comprising systematic coronary angiography, regardless of the symptoms. The frequency of associated coronary disease varies according to the characteristics of the population involved, in particular age and, to a lesser degree, the geographic origin. Series of patients with calcific aortic stenosis whose mean age is between 60 and 70 years reported 30-50 of associated significant coronary artery disease (at least one stenosis > 50 or 70 of vessel diameter). Coronary artery disease has been reported in more than 50 of patients aged > 70 years2 and, of patients aged > 80 years, in 65 in series from the USA3 and 41 in a British series.

Inflammation and cardiovascular disease

Elevated serum CRP has been associated with cardiovascular events in primary and secondary prevention cohorts, and in patients presenting with acute coronary syndromes. In a meta-analysis of 14 prospective studies, with 2557 cases (mean age of 58 years and mean follow up of 8 years), CRP concentrations in the highest versus lowest third were associated with an adjusted relative risk of 2-0 (95 CI 1-6-2-5) in primary prevention cohorts, and 1-9 (95 CI 1-5-2-3) in secondary prevention cohorts.59 Higher serum CRP concentrations may identify patients more likely to respond to aspirin or statin therapy. Among 543 cases and matched controls in the Physicians', Health Study, aspirin reduced myocardial infarction by 56 among those with the highest quarter of baseline CRP level, versus a 14 reduction in those in the lowest quarter.60 In the CARE61 and AFCAPS Texas CAPS62 studies, patients with high CRP levels benefitted from statin therapy even in the presence of low to normal LDL cholesterol....

Coronary artery disease

Overweight and obesity are now considered major independent risk factors for coronary artery disease 4 nevertheless, the impact of excess body fat and fat distribution in different populations (men and women, young and elderly, ethnic groups) remains to be fully determined. In a recent review of 11 independent studies, Anderson and Konz30 estimated an overall RR of 2-71 for women and 2-80 for men for a BMI of 33 v 23kg m2, respectively. This increased risk was partly (but not fully) accounted for by other major risk factors for coronary artery disease, including hypertension, lipids and diabetes. This may in part be accounted for by an association between obesity and other non-conventional risk factors for coronary artery disease, including alterations in coagulation and risk for thrombosis or increased inflammatory cytokines.70-72 A recent study also found a substantially increased risk for angiographically assessed coronary artery disease associated with an increase in waist...

Emergency Department Care Of Symptomatic Valvular Heart Disease

There is little that the emergency physician can do to change the structural abnormality of the diseased cardiac valve. The exception to this rule is acute mitral incompetence due to myocardial infarction. The infusion of thrombolytic therapy may reestablish blood flow to the papillary muscle, with restoration of function. 9 The alternative to thrombolytic therapy is coronary angioplasty.10 The majority of treatments are directed toward symptomatic relief of the manifestations of valvular disease. However, there are certain medical treatments that can reduce the consequences of the mechanical defect. The regurgitation of aortic and mitral incompetence may be lessened by reducing afterload. When the cause of mitral incompetence is myocardial ischemia, regurgitation can be lessened by treatment with nitrates. setting. Patients with valvular heart disease and acute pulmonary edema should be considered for Swan-Ganz catheter insertion. The presence of valvular disease, especially...

Lycopene and Cardiovascular Disease

The European Multicentre Euramic Study, which reported that risk of developing myocardial infarct was inversely related to lycopene intake, after appropriate adjustment for other cardiovascular risk factors. Some Scandinavian studies have subsequently supported this claim moreover, lycopene is capable of reducing LDL-cholesterol levels, possibly by inhibiting hydroxymethylglutaryl CoA reductase (HMGCoA reductase), the rate-limiting enzyme for cholesterol synthesis.

Gender and cardiovascular disease

In the United States the number of women who die annually from cardiovascular disease is higher than men. The cardiovascular disease burden is particularly high in older women. In women aged 55 and older, major cardiovascular diseases (ICD 390-448-9) accounted for 473569 deaths in 1997 compared to 402310 deaths in older men.1 Major cardiovascular diseases accounted for 44 of all deaths in older women and 40 of all deaths in older men. The number of deaths from coronary heart disease (CHD) was only slightly higher in older women (229 628) than in men (223 246), but the number of deaths from stroke was considerably higher in women (88768 compared to 55 149 respectively). There were 4607 deaths from pulmonary embolism in older women compared to 3465 in men. As exemplified by these absolute numbers of deaths, cardiovascular disease now represents a larger health problem in older women than in older men. Figure 20.1 Annual mortality rates by 10 year age groups for CHD, stroke, and...

STSegment Elevation Myocardial Infarction

Diagnosis Rule out myocardial infarction 3 Condition Absolute Contraindications to Thrombolytics Active internal bleeding, suspected aortic dissection, known intracranial neoplasm, previous intracranial hemorrhagic stroke at any time, other strokes or cerebrovascular events within 1 year, head trauma, pregnancy, recent non-compressible vascular puncture, uncontrolled hypertension (> 180 110 mm Hg). Relative Contraindications to Thrombolytics Severe hypertension, cerebrovascular disease, recent surgery (within 2 weeks), cardiopulmonary resuscitation.

Ablation of VT after myocardial infarction

Saline irrigation of the ablation electrode (cooled RF ablation) may create larger lesions to reach deep portions of re-entry circuits by allowing current delivery without excessive heating at the surface of the tissue, which can cause formation of coagulum that prevents further energy application. A recent multicen-tre trial evaluated a saline irrigated RF ablation catheter (Cardiac Pathways Corp, Sunnyvale, California, USA) in 146 patients (prior myocardial infarction in 82 average (SD) left ventricular ejection fraction 31 (13) ) who had an average of 25 (31) episodes of VT in the two months before ablation despite antiarrhythmic drug treatment.10 All mappable VTs were eliminated in 75 of patients. During a follow up of 243 days 54 of patients remained free of spontaneous VT 81 experienced a more than 75 reduction in the number of VT episodes in the two months after ablation, as compared to before ablation. comitant illnesses. Ablation is often a late attempt in controlling...

Evidence for an association between childhood factors and heart disease risk

Heart disease morbidity and mortality Forsdahl. Are poor living conditions in childhood and adolescence an important risk factor for arteriosclerotic heart disease 2 Barker et al. Infant mortality, childhood nutrition, and ischaemic heart disease in England and Wales.3 In the counties where infant mortality (INFmo) was high, the same generation had both a high total mortality and ischaemic heart disease (IHD) mortality in middle age. Variations in IHD mortality rate between counties is linked to variations in poverty in childhood and adolescence because INFmo is a reliable index of standard of living. Forsdahl suggested that poverty followed by prosperity is a risk factor for IHD. Barker et al. Weight in infancy and death from ischaemic heart disease.4 thinness at birth to death for cardiovascular disease in adult In children at 10 years and adults at 36 years systolic blood pressure was inversely related to birth weight (independent of gestational age). Within England and Wales 10...

Early life factors and intermediate heart disease risk factorsconditions

Measures and heart disease measures and heart disease CHD, coronary heart disease CVD, cardiovascular disease LDL, low density lipoprotein. CHD, coronary heart disease CVD, cardiovascular disease LDL, low density lipoprotein. which is an important risk factor for heart diseases. Observations are not consistent weak, non-linear or insignificant correlations between birth weight and blood pressure have been reported,20 w22 particularly among younger populations. Figure 27.1. Intrauterine programming by prenatal determinants and life course factors in heart diseases (GF, growth factor). ADULT HEALTH Hyperglycaemia Glucose intolerance Hypertension Coronary heart disease Stroke Figure 27.1. Intrauterine programming by prenatal determinants and life course factors in heart diseases (GF, growth factor). The main associations between birth weight and other growth measures and heart disease are summarised in table 27.2.

Suggested biologicalenvironmental mechanisms underlying the evolution of heart disease risk

The growth of the fetus is a complex process which is still insufficiently understood. A key concept in the fetal origin hypothesis is fetal undernutrition, and its relation with adult diseases. The human evidence, as described above, is based on studies where birth measures have been related to different adult heart disease outcomes in different populations. This is strongly supported by the animal experiments, and stresses the importance of the feto-maternal environment. Barker5 has differentiated undernutrition during pregnancy by trimesters, and he suggests that the down regulation of growth during the first trimester leads to a proportionately small child who has increased risk of raised blood pressure and may possibly die of haemorrhagic stroke. Under-nutrition during the second trimester leads to a disturbed fetoplacental relation, and insulin resistance or deficiency consequently birth weight is reduced and the baby is thin, and has an increased risk of raised blood pressure,...

Thrombolysis in Acute Ischemic Stroke

BACKGROUND Significant progress has been achieved in the last 10 years toward identifying potential therapies for ischemic stroke. The most important single step, however, has been the 1995 publication of the results of the NIH National Institute of Neurologic Disorders and Stroke (NINDS) trial evaluating the use of intravenous recombinant rt-PA. This trial demonstrated, for the first time, that stroke was a treatable disease in carefully selected patients who received rt-PA within 3 h of symptom onset. The time-critical nature of thrombolytic therapy highlights the need for the involvement of emergency medicine in a coordinated, multidisciplinary approach to the treatment of stroke patients. The NIH NINDS study was a randomized, double-blind, placebo-controlled trial conducted at 40 geographically diverse hospitals (30 community and 10 university settings) comparing intravenous rt-PA (0.9 mg kg maximum dose, 90 mg) against placebo in 624 patients meeting specific enrollment criteria....

Secondary Stroke Prevention Transient Ischemic Attacks

Although limited proven pharmacologic interventions exist to reverse an acute ischemic stroke, considerable options have been identified with regard to secondary stroke prevention in patients with a completed stroke or TIA. Agents preventing platelet aggregation form the cornerstone of secondary prevention of stroke in those patients without atrial fibrillation or high-grade carotid stenosis as a contributing factor. The use of acetylsalicylic acid (aspirin) is associated with a stroke risk reduction of 20 to 25 percent compared with placebo. Aspirin decreases the synthesis of thromboxane A2 by irreversibly inhibiting cyclooxygenase for the life of the platelet, causing decreased platelet aggregation. No dose-effect statistically significant 0.5 percent absolute reduction in the annual risk of ischemic stoke, myocardial infarction, or vascular death when compared with aspirin (325 mg day).24 No combination studies have been reported. The use of clopidogrel is ideal for those patients...

Methods For Lowering Perioperative Cardiac Risk Coronary bypass surgery

Recently, attention has turned to evaluating the effectiveness of methods for intervening to lower risk of cardiac complications during elective surgery. Coronary revascularisation is one such intervention. A retrospective review by Eagle and colleagues of the CASS (coronary artery surgery study) registry data supports such a protective effect.7 These data demonstrate that patients undergoing elective vascular surgery, who had previously undergone coronary artery bypass grafting, did better than control patients who had similar amounts of coronary disease, but no surgical coronary revascularisation. This type of analysis does not take into consideration the cumulative risk of both coronary and peripheral revascularisation, and so does not necessarily argue for prophylactic surgical coronary revascularisation before elective peripheral vascular surgery. But it does suggest a protective effect of prior coronary bypass surgery. Data from the Cleveland Clinic showed similar findings that...

Single gene cardiovascular disorders

Several cardiovascular disorders have been shown to have a familial basis. These diseases cover a wide spectrum, from structural defects such as familial atrial septal defects to functional defects such as long QT syndrome (Table 23.1). For most of these diseases the chromosomal location (locus) has been mapped but the gene has not yet been identified. However, diseases such as the cardiomyopathies, particularly hypertrophic cardiomyopathy, have undergone major investigations, with elucidation of the pathogenesis. Animal models of human familial HCM have been developed and therapies have been evaluated. There is considerable progress in the identification of genes responsible for ventricular arrhythmias, particularly the long QT and Brugada syndromes. It is still premature to manage these disorders based on their genetic etiology. This is partly because genetic screening is not available and the populations studied have not yet been adequately characterized to provide generalized...

Phytochemicals And Cardiovascular Disease

Oxidative reactions have been linked to atherosclerosis through several different mechanisms. The most widely studied hypothesis of lipid oxidation and atherosclerosis involves the formation of oxidized, cytotoxic lipoproteins, particularly low-density lipoprotein (LDL) (37). During the oxidation of LDL, the lipoproteins become modified through either direct free-radical attack or formation of adducts between proteins and lipid oxidation products. The oxidized LDL can then be recognized and engulfed by macrophages, leading to the formation of foam cells that accumulate in arterial walls and form plaques (Fig. 2). Oxidized LDL has also been postulated to cause vascular inflammation and stimulate autoimmune reactions. Evidence supporting the relationship between LDL oxidation and cardiovascular disease is increasing however, the importance of this mechanism to the development of cardiovascular disease has yet to be fully understood. Figure 2. The proposed mechanism for promotion of...

Subacute Ischemic Stroke

EMBOLIC STROKE Patients with embolic stroke who have minor deficits should undergo anticoagulation. Older studies, which included patients with mechanical valves, found that 12 to 14 percent of stroke patients had recurrent emboli within 2 weeks of the initial event, some within 24 h. More recent trials found that only 1.5 percent of patients had recurrent embolism in the first 7 days,20 suggesting immediate administration of anticoagulants is unnecessary. The exact timing, method, and degree of anticoagulation following a stroke remain controversial, with little clear data guiding its use. Consultation and or locally approved specific protocols on its use are recommended. Anticoagulation with heparin should be withheld for 3 to 4 days following large cardioembolic stroke, because of the increased risk of spontaneous hemorrhagic changes associated with heparin in these types of strokes. The use of low-molecular-weight heparin and heparinoids in improving outcome remains to be proven....

Myocardial infarction and other nonfatal end points

Registry studies have suggested a favorable effect on late myocardial infarction only among the highest risk subsets, such as patients with three vessel disease and severe angina pectoris.12 In the meta-analysis, no overall effect of CABG on subsequent infarction could be demonstrated, primarily because of an excess of infarction in the perioperative period (10-3 incidence of death or myocardial infarction at 30 days) among those assigned to surgery.7 Although the risk of subsequent myocardial infarction was lower during extended follow up, this was not statistically significant (24-4 incidence of death or myocardial infarction at 5 years for the CABG group v 30-7 for the medical group).7 Most trials did not prospectively collect data on rehospitalization for unstable angina, stroke, quality of life, or cost.

Evaluation Of Fever In Infants With Heart Disease

Infants and children with known heart disease are prone to the same illnesses as other children. When they are brought to the emergency department for treatment of febrile illnesses, they are most likely to be hemodynamically stable and capable of handling the illness. Any signs of congestive heart failure are indications for an admission. Otherwise, blood cultures should be obtained, as well as a complete blood count, as would be performed for any infant between the ages of 6 months and 24 months. Although occult bacteremia has the same probability for occurrence in a child with congenital heart disease, concern for bacterial endocarditis must be greater. Oral or parenteral antibiotics should be administered with great care if presumptively treating early bacteremia or subacute bacterial endocarditis. It is more prudent to arrange admission, repeated cultures, and expectant therapy for such infants than to begin antibiotic therapy blindly simply because of the presence of congenital...

Ace Inhibition In Heart Failure And Ischaemic Heart Disease

Many clinical trials demonstrate the therapeutic benefit of ACE inhibition in heart failure and ischaemic heart disease. It is of note, however, that the effects of ACE inhibitors are dose related. Large clinical trials, by necessity, use only one dose of any drug. The results of such trials are just as much a measure of the effect of the dose as they are a measure of the effect of the drug. Use of a less than optimal dose may fail to reveal a drug's true therapeutic potential. This is of particular concern in a head-to-head comparison of two active drugs, where the result may be more due to choice of dose than to choice of drug. Clinicians should strive to achieve drug doses that have proven to be of benefit in clinical trials. At present, a large proportion of patients receiving ACE inhibitor therapy are receiving less than optimal doses (Lenzen et al 2005). Measurement of plasma Ang peptide levels is not feasible for the monitoring of ACE inhibitor therapy, but measurement of...

Ischaemic heart disease

Major clinical predictors of perioperative cardiac complications are patients with recent (within 6 months) myocardial infarction, severe or unstable angina, and significant arrhythmias. However, many patients have controlled ischaemic heart disease and, although there are a number of tests available to assess this group, they are not necessarily helpful. History, examination, and resting ECG can readily categorise risk (Table 10.2). quantify risk and these are based on observational studies. Probably the most useful measure with regard to ischaemic heart disease is the patient's functional ability. Risk is increased in patients who cannot reach 4 METS (metabolic equivalents) workload 1 MET is equivalent to the oxygen consumption of a resting 40-year-old 70 kg man. Climbing a flight of stairs, briskly walking on the flat, mowing the lawn, swimming, or playing a round of golf is at least 4 METS. Overall, less than 10 surgery is associated with a perioperative cardiac event. However,...

Heart disease and pregnancy

Pregnancy in most women with heart disease has a favourable maternal and fetal outcome. With the exception of patients with Eisenmenger syndrome, pulmonary vascular obstructive disease, and Marfan syndrome with aortopathy, maternal death during pregnancy in women with heart disease is rare.1-4 However, pregnant women with heart disease do remain at risk for other complications including heart failure, arrhythmia, and stroke. Women with congenital heart disease now comprise the majority of pregnant women with heart disease seen at referral centres. The next largest group includes women with rheumatic heart disease. Peripartum cardiomyopathy, though infrequent, will be discussed in view of its unique relation to pregnancy. Two groups of conditions not discussed further are coronary artery disease, infrequently encountered, and isolated mitral valve prolapse, which generally has an excellent outcome. Cyanotic heart disease unrepaired and repaired In uncorrected or palliated pregnant...

Tocopherols and Cardiovascular Disease Epidemiological Evidence

The effects of dietary vitamin E have been examined in several studies, many of which have reported a clear association between the reduction in the relative risk of CVD and high intake or supplement of vitamin E, although some have shown no such association. The Vitamin Substudy of the WHO MONICA Project showed that in European populations whose classical risk factors for CVD were very similar, the 7-fold differences in CVD mortality could be explained at least to approximately 60 by differences in the plasma levels of vitamin E and up to 90 by the combination of vitamins E, A, and C. The Edinburgh Case Control Study and Basel Prospective Study consistently revealed an increased risk of ischemic heart disease and stroke for low plasma levels of vitamin E. However, other European population studies have not found an association between blood levels of vitamin E and end points of CVD. In the EURA-MIC study, the adipose levels of vitamin E did not correlate with the relative risk of...

Acute myocardial infarction in hospital

Yet another problem in identification of the natural history of acute myocardial infarction is that fully 25 of non-fatal infarctions are silent.8 Silent infarction can be detected only when a subject is seen more than once at annual intervals or longer, and an ECG performed on the second occasion shows new pathological Q waves. Most clinicians can remember such cases, but an estimate of the incidence can be made only when a cohort of the population free from coronary heart disease is followed for a number of years. This happened in the Framingham study a unique and prestigious study which has taught us more than any other about the changing pattern of coronary heart disease during the latter half of the 20th century.9

Adult Congenital Heart Disease In General Echocardiography Practice

Congenital Echo Images

The spectrum of adult congenital heart defects seen in echocardiography practice varies according to institutional practice and expertise. Half a century ago, survival with severe congenital heart disease was less common. Today, nearly 80 of such patients in industrialized societies now survive into adulthood. Most are followed up in centers that specialize in adult congenital heart diseases (CHDs), but it is not uncommon for such adults to be seen in general echocardiography practice. Congenital Heart Disease in Adults Compatible With Survival to Adulthood With No Prior Surgery or Intervention Superimposed acquired age-related heart disease, e.g., hypertension, coronary artery disease. Spectrum of Congenital Heart Disease Modified from Kisslo JA, Adams DB, Leech GJ. Essentials of Echocardiography Congenital Heart Disease. New York Ceiba-Geigy, 1988. Fig. 5. Morphological left and right ventricle. What defines right vs left ventricle are the morphological characteristics. On...

Arteriosclerotic Heart Disease ASHD

The healthy heart and cardiovascular system tolerates even extreme hypoxia very well. Numerous ECG studies, echocardiograms, heart catheterizations and exercise tests do not demonstrate cardiac ischemia or cardiac dysfunction in healthy persons at high altitude, even when arterial Pa O2 was less than 30 mmHg. Those with arteriosclerotic disease may not have the same adaptive capabilities and intuitively seem more likely to suffer from acute cardiac events. Epidemiologic data, however, do not support this supposition. Morbidity and mortality from arteriosclerotic heart disease is reduced in persons with long-term residence at high altitude, and visitors apparently do not have increased risk of acute myocardial infarction. Recent work, however, suggested earlier onset of angina at high altitude compared with sea level during the first few days at 2500 m. After five days, an elderly group with CAD acclimatized well, and performed at sea-level exercise capacity without increased or...

Stroke Transient Ischemic Attack And Other Central Focal Conditions

The use of tissue plasminogen activator for select patients with ischemic stroke requires a high level of involvement by emergency physicians. The etiology of stroke is diverse, ranging from cardiac emboli to a rupture of a congenital berry aneurysm. Effective treatment for one stroke type may be disastrous when applied to another stroke type. The anatomic location of the lesion and the mechanism of the stroke must be determined before effective treatment can be administered.

Biological programming a new theoretical model about the aetiology of heart disease

The dawn of modern epidemiology came after the second world war, first with ecological studies comparing CVD incidence and mortality, and subsequently multicentre cross sectional and follow up studies on CVD.w3 The studies showed that populations with high CVD mortality have high cholesterol and high blood pressure, and that smoking and obesity are common among these populations.4 This led to the lifestyle model in understanding the aetiology of chronic diseases, where the key issues are health behaviour and the interaction between genes and an adverse environment in adult life. This was consequently followed by intervention programmes, which have significantly improved heart disease risk status in many countries.w3 However, lifestyle factors only explain part of the heart disease risk, which is why other reasons have been sought. For example, in the mid 1980s Rose pointed out that the well established risk factors for coronary heart disease (CHD) cigarette smoking, high serum...

Other possible models in the evolution of heart diseases and limitations of the studies

Figure 27.1 shows a simplified framework for the diVerent associations between the various factors in the prenatal period and their eVect on adult health. It is evident that no single model is able to explain heart disease risk. 2. Forsdahl A. Are poor living conditions in childhood and adolescence an important risk factor for arteriosclerotic heart disease Br J Prev Social Med 1977 31 91-5. 3. Barker DJP, Osmond C. Infant mortality, childhood nutrition, and ischaemic heart disease in England and Wales. Lancet 1986 i 1077-81. 4. Barker DJP, Winter PD, Osmond C, et al. Weight in infancy and death from ischaemic heart disease. Lancet 1989 ii 577-80. 5. Barker DJP. Fetal origins of coronary heart disease. BMJ 1995 311 171-4. relation of small head circumference and thiness at birth to death from cardiovascular disease. BMJ 1993 306 422-6. 9. Osmond C, Barker DJP, Winter PD. Early growth and death from cardiovascular disease in women. BMJ 1993 307 1519-24. 10. Vagero D, Leon D. Ischemic...

Myocardial Infarction

However in some patients, perhaps due to the hypercoagulable state associated with surgery, acute coronary syndromes will occur and present dramatically with extreme ST-elevation infarctions and even abrupt cardiac arrest. Treatment includes moving the patient to a monitored setting, and following ACLS protocols as indicated. In all cases, pain control, oxygenation, nitroglycerin, and aspirin therapy should be addressed or considered. Unless contraindicated, all patients should receive beta-blockers. Also, use of heparin and other thrombolytic therapy may be considered and cardiology consultation is appropriate.

The Genetic Origin of Congenital Heart Disease in Down Syndrome

Heart disease and defects of the cardiovascular system are responsible for the majority of premature deaths caused by congenital defects (Clark, 1987). Congenital heart disease (CHD) is particularly common in individuals with DS. It is detectable in 40-60 of individuals with DS and at autopsy in almost 70 of DS individuals. The schematic view of heart development shown in Figure 20.7 illustrates many of the regulatory molecules that play FIGURE 20.8. To identify the genes responsible for DS congenital heart disease (CHD), we compared the regions of chromosome 21 duplicated in eight different individuals with DS (represented by the black lines). The white box represents a single-copy region in individual DUP21ZSC. The region of overlap (candidate region) spans from D21S3 to at least PFKL and contains at least 35 known genes (shown on the right) (Hattori et al., 2000). Five of these genes are known to be expressed in the heart and may therefore contribute to heart disease in DS SH3BGR,...

General Approach to Treatment of Ischemic Stroke

Upon entry of patients with ischemic stroke into the emergency medical service (EMS) or emergency department setting, priority should be given to airway management and oxygenation. Patients should be placed on oxygen, the head of the bed slightly elevated, and a monitor and intravenous line established. Unless there is hypotension, fluids should be administered judiciously to prevent cerebral edema. Volume depletion in patients with ischemic stroke deserves prompt treatment, because it may contribute to decreased cerebral blood flow in the ischemic region. Avoidance of dextrose-containing solutions is warranted except in those with proven hypoglycemia. Hyperglycemia has been associated with an increase in infarct volume and poor long-term outcome. 67 Patients with fever should have antipyretics promptly administered. Experimental studies suggest that hyperthermia increases CNS metabolic demands, whereas hypothermia has demonstrated neuroprotective effects. The use of anticonvulsants...

Serum cholesterol and ischemic heart disease

Evidence from genetics, animal studies, experimental pathology, epidemiologic studies and clinical trials indicates conclusively that increasing serum cholesterol is an important cause of ischemic heart disease and that lowering serum cholesterol reduces the risk,5,6 and the results of six large randomized trials of statins have ensured that this is now widely accepted.1,7-11 Three important practical questions arise the nature of the dose-response relationship, the size of the effect, and the speed of the reversal of risk. To answer these questions data from both observational epidemiology (cohort studies) and randomized controlled trials are necessary. The two are complementary examining trial data alone is misleading. Table 12.1 summarizes the advantages of each. In cohort (or prospective) studies serum cholesterol is measured in a large number of individuals and subsequent heart disease mortality (or incidence of myocardial infarction) is recorded. Cohort studies are easier to...

Large Scale Community Coronary Heart Disease and Diabetes Prevention Trials

The results of early large-scale community CVD prevention trials, such as the Stanford Three Community and Five Community studies as well as the Minnesota Heart Health Program, had limited impact on weight status and reinforced the difficulty of preventing weight gain in the community. However, later programs, such as the Pawtucket Heart Health Program, were able to make a modest impact on weight gain in the intervention community after 10 years. These programs demonstrate the time lag that can be expected between the implementation of a truly community-wide program and the extent of behavior change likely to be required to impact upon the weight status of the community. It has been suggested that unless weight is the primary outcome of the intervention, it is unlikely that sufficient focus will be placed on achieving the level of change required to impact on energy balance and community weight status.

TABLE 473 Short Term Risk of Death or Nonfatal Myocardial Infarction in Patients with Unstable Angina

Myocardial ischemia and its sequelae usually occur as a result of fixed atheroscerotic lesions or secondary reduction in myocardial blood flow due to coronary arterial spasm, disruption of atherosclerotic plaques, and platelet aggregation or thrombus formation. Nonatherosclerotic etiologies of acute myocardial infarction are considerably less common (TabjeiZ-l).

Cardiovascular Disease Population Studies

The incidence of cardiovascular disease within populations with either very high or very low intakes of n-6 fatty acids may provide some indication for optimal intakes of n-6 fatty acids. Within populations with low n-6 fatty acid intakes (< 3 ) there would appear to be a benefit of having a higher n-6 fatty acid intake on cardiovascular disease risk reduction. These observations suggest that very low n-6 fatty acid intakes increase the risk for cardiovascular disease. The presence of EFA deficiency in a significant proportion of such populations may explain the increased risk. Several populations, including the Israelis, Taiwanese, and Kung bushmen in the African Kalahari desert, have high to very high intakes of n-6 fatty acids. The contribution of n-6 fatty acids to total energy intake is about 10 in the Israelis and Taiwanese and about 30 in the Kung bushmen. Rates of cardiovascular disease are low in the Taiwanese, where dietary n-6 fatty acids are obtained mainly from soybean...

Acute coronary syndromes presentationclinical spectrum and management

Acute coronary syndromes define a spectrum of clinical manifestations of acute coronary artery disease. These extend from acute myocardial infarction through minimal myocardial injury to unstable angina. This spectrum shares common underlying patho-physiological mechanisms. The central features consist of fissuring or erosion of atheromatous plaque with superimposed platelet aggregation and thrombosis. This is complicated by microfragmentation and distal embolisation with alterations in vascular tone in affected myocardium. As a consequence, clinical manifestations are dependent upon the severity of obstruction in the affected coronary artery (fig 3.1), the presence or absence of collateral perfusion, and the volume and myocardial oxygen demand within the affected territory. Thus, the spectrum extends from abrupt occlusion with acute ischaemia leading to infarction, through Table 3.1 Acute coronary syndromes The distinction between acute myocardial infarction and minimal myocardial...

Part B Acute Coronary Syndromes

Coronary artery disease is the most common cause of death in the United States, accounting for approximately 600,000 deaths annually. Of 6.0 million ED visits per year for chest pain, about 1.2 million people are diagnosed with myocardial infarction and another million with unstable angina. It has been estimated that the overall cost of coronary artery disease exceeds 100 billion dollars annually in the U.S. There is also a significant cost in terms of malpractice claims, with missed myocardial infarction and acute coronary syndromes continuing to constitute a large percentage of both claims and costs. Mortality and morbidity continue to decrease with advances in therapy. There was a 54 reduction in age-adjusted mortality from myocardial infarction in the U.S. from 222 100,000 in 1963 to 101 100,000 in 1990. Coronary artery disease (CAD) is a spectrum of disease that ranges clinically from asymptomatic or silent to one of the following clinical syndromes stable angina, variant angina...

Prevention of cardiovascular diseases89

9 Global perspective on cardiovascular disease 91 K Srinath Reddy 11 Tobacco and cardiovascular disease achieving smoking cessation 114 Godfrey H Fowler 12 Lipids and cardiovascular disease 121 Malcolm Law 13 Use of lipid lowering agents in the prevention of cardiovascular disease 130 Jeffrey L Probstfield 14 Blood pressure and cardiovascular disease 146 Curt D Furberg, Bruce M Psaty 15 Glucose abnormalities and cardiovascular disease dysglycemia as an emerging 161 cardiovascular risk factor 16 Physical activity and exercise in cardiovascular disease prevention and rehabilitation 170 Erika S Froelicher, Roberta K Oka, Gerald F Fletcher 17 Psychosocial factors in the primary and secondary prevention of coronary heart disease 181 an updated systematic review of prospective cohort studies 20 Postmenopausal hormone therapy and cardiovascular disease 244 Jacques E Rossouw 21 Ethnicity and cardiovascular disease 259 Sonia S Anand, Stephanie Ounpuu, Salim Yusuf 22 The fetal origins of...

Ischemic Stroke

Neurons are very sensitive to changes in cerebral blood flow. Brain cells die within a few minutes of complete cessation of blood flow. However, despite complete occlusion of a cerebral vessel during an acute ischemic stroke, some perfusion remains even in the center of the ischemic brain region, due to collateral flow and variations in local tissue pressure gradients. Cells vary from irreversibly injured neurons in the center of the ischemic region to reversibly injured neurons in the periphery (the penumbra). The degree and duration of occlusion determine the viability of the cells in the penumbra. Theoretically, the earlier reperfusion occurs, the greater is the chance of cell survival. The use of intravenous and intraarterial thrombolytic therapy for ischemic stroke is based on this rationale as well as on investigative trials involving the use of neuroprotectant drugs.

Heart Disease

A high zinc copper ratio has been linked to hypercholesterolemia 103 . Thus, by virtue of its ability to bind these divalent cations and potentially alter their balance and availability 7,8 , PA may also affect serum cholesterol levels Figure 14.3(C) . In fact, some foods rich in PA, such as bengal gram beans, have been shown to have hypocholesterolemic effects 104 . Although cereal fiber has been associated with decreased coronary heart disease risk 105 and wheat fiber left over from the amylolytic digestion of wheat flakes, which may contain some PA, have been suggested to favorably affect serum cholesterol 106 , wheat bran, a rich source of PA, has not been shown to reduce blood lipid levels 107,108 . A reduction of serum cholesterol as a result of PA supplementation has been shown in animal studies 109-111 . Sharma 110 showed that the addition of 0.2 PA to a high-cholesterol diet in hypercholesterolemic rats reduced serum cholesterol along with serum triglycerides. Jariwalla et...

Preface to the Second

The recent proliferation of carefully controlled large scale clinical trials, their meta-analyses and selective observational studies has contributed to the remarkable strides made in the management of cardiovascular disease. One of the prophesies stated in the first edition of this textbook has come to pass - namely, that management guided by external evidence is an evolving process as newer and more effective treatment modalities come to light. While successful as a critical approach for managing patients, evidence-based medicine is nevertheless a work in progress which, if allowed to rest on its laurels, will by nature be threatened with impending obsolescence. In addition to keeping abreast of new information, there is a need to integrate and distill the information into coherent recommendations. Authors were therefore instructed to provide their recommendations including those based on qualitative Judgments. The recognition of new developments in a rapidly changing dynamic field...

Preface to the First edition

The advent of large scale prospective randomized clinical trials has strengthened the external evidence upon which management decisions can be made with some confidence. We have come to rely on so-called external best evidence as critical guideposts for establishing minimal criteria for treatment of many cardiovascular disorders. In the process, some myths based on putative mechanisms have been dispelled while insights into the efficacy of new treatments have been more rapidly facilitated. on the other hand there is a danger of righteous complacency which, if unchecked, could lead to a slavish dependency on statistical bottom lines and, ultimately, to cook book medicine. It is the intent of this textbook to present a proper balance between objectivism and empiricism. In this regard, the very first chapter begins by defining the practice of evidence-based cardiology as integrating individual clinical expertise with the best available external clinical evidence from systematic research....

The sequence of thrombotic events

Thrombosis caused by disruption. The cap of the plaque has torn and thrombus within the lipid core extends into and occludes the lumen. This is the typical lesion of acute myocardial infarction. Figure 1.4. Thrombosis caused by disruption. The cap of the plaque has torn and thrombus within the lipid core extends into and occludes the lumen. This is the typical lesion of acute myocardial infarction. occlude the artery, leading to a final stage in which there is a loose network of fibrin containing large numbers of entrapped red cells. This third and final stage thrombus may propagate distally after the onset of myocardial infarction. The final stage of occlusive thrombus has a structure making it very susceptible to either natural or therapeutic lysis, but this will expose the deeper and earlier thrombus which is more resistant to lysis.

A critical appraisal of the cardiovascular history and physical examination

There have been numerous technological advances made in the diagnosis and treatment of cardiovascular disease. In spite of this, a carefully conducted clinical examination remains the cornerstone in the initial assessment of the patient with known or suspected cardiovascular disease. Before conducting further laboratory or radiologic diagnostic tests, clinicians implicitly consider each piece of historical information and each finding from the physical examination as a diagnostic test that increases or decreases the probability of the possible diagnoses. The competency and accuracy of the clinical examination is therefore crucial, for it serves as the basis for our judgment regarding not only diagnosis, but prognosis and therapy as well. This chapter is not intended to provide details of how to perform a cardiovascular history and physical examination, and should be read in conjunction with standard textbooks on cardiology to obtain such information. Instead, we will provide the...

Plaque disruption the healing process

The great majority of episodes of plaque disruption do not cause a major event such as infarction or death. Minor episodes of erosion or disruption are often clinically silent but do contribute to the episodic progression of coronary artery disease seen on sequential angiography.

Obtaining incremental information from diagnostic tests

A 75 year old male presents with a history of exertional chest pain. The patient describes substernal chest pain that he perceives as a pressure sensation occurring when he walks too fast, uphill, or in the cold. It is relieved by rest within a few minutes. On two recent occasions, he tried a friend's nitroglycerin tablets, and obtained even more rapid relief of his symptoms. His symptoms have never occurred at rest. The patient has a history of diabetes mellitus, hypertension, and hypercholes-terolemia. He smokes one pack of cigarettes a day. Several male family members died of coronary artery disease before the age of 60. The patient underwent carotid artery surgery a year ago for treatment of transient ischemic attacks. On the basis of his age, gender, chest pain description, and risk factors, this patient is highly likely to have significant obstructive coronary artery disease (CAD). The added, or incremental, value of any stress test for the...

Vascular smooth muscle cells

If the lesion ruptures or erodes platelets rapidly accumulate and intravascular thrombosis can occur, leading to the acute coronary syndromes of unstable angina and myocardial infarction. Plaques with a large lipid pool and a thin fibrous cap are much more prone to rupture than those with a thick cap, partly because a thick fibrous cap is more able to resist local mechanical stresses. However, the most important determinant of plaque stability is the composition of the fibrous cap, in that a preponderance of inflammatory cells and a relative paucity of VSMCs leads to plaque rupture.6

Clinical trials and metaanalysis

It is important to appreciate that progress in cardiologic practice, and in the prevention of cardiovascular disease, has been and remains dependent on the availability of large-scale randomized trials and appropriately large-scale meta-analyses of such trials. In the management of acute myocar-dial infarction (MI), for example, these methods have helped to demonstrate that fibrinolytic therapy,1-3 aspirin,1,3,4 Even when studies have been properly randomized and well conducted, moderate biases can still be introduced by inappropriate analysis or interpretation. One well recognized circumstance is when patients are excluded after randomization, particularly when the prognosis of the excluded patients in one treatment group differs from that in the other (such as might occur, for example, if non-compliers were excluded after randomization). This point is well illustrated by the Coronary Drug Project, which compared clofi-brate versus placebo among around 5000 patients with a history of...

Definition of the syndrome

Based upon trial data and prospective registries the following features define patients with an acute coronary syndrome Ischaemic chest pain (discomfort) at rest or on minimal exertion or emotion (2 x 5 minute episodes or 1 episode > 10 minutes). and - Evidence of coronary artery disease on angiography or perfusion scanning. Patients with typical clinical features of unstable angina but a normal ECG and no prior documented coronary disease have a suspected acute coronary syndrome until enzymes and further ECGs confirm or refute the diagnosis. Those with persistent ST elevation have suspected acute myocardial infarction and their management is considered elsewhere.

Identification of high risk and low risk patients

Prior risk is determined by systemic risk factors such as age, diabetes, hypertension, smoking, heart failure, and previous infarction. Such factors influence the extent of underlying coronary artery disease and left ventricular dysfunction, and their impact may be revealed by echocardiography, stress testing, perfusion scanning or coronary angiography. Acute ischaemic risk is determined by the severity of impaired perfusion, the volume of myocardium affected, and the consequent changes in mechanical and electrical function. The distinction is important because a patient with a minor ischaemic event may nevertheless have extensive underlying coronary artery disease, and management strategies need to address both aspects of care. The converse may also occur. A detailed discussion of risk prediction in acute coronary syndromes has been covered elsewhere.5 The key factors predicting adverse risk are summarised in the adjacent box. Readily available clinical characteristics can be used to...

Management of unstable angina and minimal myocardial injury

Presentation and general measures Patients with an acute coronary syndrome may present de novo with new onset angina CCS (Canadian Cardiovascular Society) class III or IV, or following abrupt deterioration of previously stable angina with more severe and prolonged symptoms and diminished responsiveness to glyceryl trinitrate. The - prior myocardial infarction or heart failure symptoms may be present at rest or may be precipitated by minor exertion or emotion. Where such symptoms develop within the first two weeks following acute myocardial infarction, there is an increased risk of acute occlusion. Patients with acute coronary syndromes may present directly to emergency departments (especially with acute infarction or severe ischaemia) but they may also present to chest pain clinics, care of the elderly units or to primary care physicians. On presentation a 12 lead ECG should be performed whenever possible during an episode of pain. This provides valuable diagnostic information....

Adenosine diphosphate antagonists

The platelet adenosine diphosphate inhibitor clopidogrel has been employed as an adjunctive antiplatelet agent during coronary stenting. It appears to offer similar benefits to those of ticlopidine but with a more favourable safety profile (severe neutropenia as infrequent as that of aspirin 0.04 clopidogrel v 0.02 aspirin). Chronic treatment with clopidogrel offers approximately a 9 risk reduction compared with aspirin treatment and it is specifically indicated in those with aspirin intolerance. The use of combination aspirin and clopidogrel in acute coronary syndromes is currently under evaluation.

Glycoprotein IlbIIIa inhibitors

Despite the undoubted benefits of aspirin, patients with acute coronary syndromes nevertheless suffer important risks of subsequent cardiac events. In the presence of a potent thrombogenic stimulus, like that which follows rupture of an atheromatous plaque, the effects of aspirin may be overcome and platelet aggregation ensues. Cross linking of platelets occurs via the glycoprotein IIb IIIa receptor, with fibrinogen acting as the bridge.10 Large scale clinical trials have been conducted with three glycoprotein IIb IIIa inhibitors abciximab, tirofiban, and eptifibatide. More than 32 000 patients have been randomised in clinical trials of glycoprotein IIb IIIa inhibitors (16 trials) and a highly significant benefit is observed for the combined end point of death or myocardial infarction at 48 hours, 30 days, and six months. Overall, there are approximately 20 fewer events per thousand patients treated.11 A highly significant benefit is also observed on the combined end point of death...

Antithrombin treatment

Trials have also been conducted of low molecular weight heparin versus unfraction-ated heparin and two of these trials (ESSENCE and TIMI 11b, both using enoxa-parin) have indicated superiority, with an absolute reduction of 30 events per 1000 patients treated (death myocardial infarction refractory angina). These benefits are seen without excess major bleeding but with some increase in minor bleeding including bruising at puncture sites. Other trials of low molecular weight heparins have not shown benefit over unfrac-tionated heparin, but the overall conclusions are as follows

International perspectives

Then cost may differ among countries due to either differences in the quantity of resources used to provide a service, price differentials for the same resources, or both. A specific example will help illustrate these concepts (Table 6.4). Care of a patient with acute myocardial infarction given thrombolysis includes the cost of the drug, the cost of basic hospital care, and the cost of additional tests and treatments in the convalescent phase. Table 6.4 presents hypothetical costs of basic care in two countries, with monetary values expressed in dollar units for simplicity. The costs of drugs in Country 1 are higher than in Country 2, where drug prices are strictly regulated. The time spent by the hospital staff to care for the patient are quite similar in Country 1 and Country 2 (50 hours per patient for Treatment A and 54 for Treatment B, a difference due to lower complication rates with Treatment A). The average hourly compensation for hospital staff is, however, higher in Country...

Calcium entry blockers

Calcium antagonists act by inhibiting the slow inward current induced by the entry of extracellular calcium through the cell membrane. They lower myocardial oxygen demand and reduce arterial pressure and contractility. Some agents induce a reflex tachycardia and these are best administered in combination with a P adrenoceptor antagonist. In contrast, diltiazem and verapamil are suitable for patients who cannot tolerate a P blocker because they slow conduction through the atrioventricular node and tend to cause brady-cardia. Calcium entry blockers have been shown to reduce the frequency of angina. A meta-analysis of calcium entry blockers in acute coronary syndromes indicates a nonsignificant trend towards higher mortality versus control patients (5.9 v 5.2 in 7551 patients). In individual trials, diltiazem has been compared with propranolol and both agents produced a similar reduction in anginal episodes. In summary, patients unable to tolerate P blockers should have a heart rate...

Cost effectiveness analysis

Another principle is that the costs included in cost effectiveness analysis should be comprehensive. The cost of a specific therapy should include the cost of the intervention itself (for example, thrombolytic therapy for acute myocardial infarction) and the costs of any complications the therapy induced (for example, bleeding), less any cost savings due to reduction of complications (such as, heart failure). The need for other concomitant therapy should also be included, which is particularly important when assessing the cost effectiveness of screening programs or diagnostic testing strategies.

Patient selection and cost effectiveness

Drugs and procedures in medicine are applied to different patient groups for different clinical indications. The medical effectiveness of therapies varies considerably according to patient selection. Cholesterol lowering therapy, for instance, will extend the life expectancy of a patient with multiple cardiac risk factors more than it will for a patient with the same cholesterol level and no other cardiac risk factors. Coronary bypass surgery provides greater life extension to a patient with left main coronary artery obstruction than it does to a patient with single vessel disease.18 The cost effectiveness ratio for these therapies will therefore vary among patient subgroups due to the impact of patient characteristics on the clinical effectiveness of therapy, which forms the denominator of the cost effectiveness ratio. Similarly, the cost of a particular therapy may also vary according to patient characteristics, since the therapy itself may be more

Diagnostic tests and cost effectiveness

The information provided by a test may be used in different decisions, and the test may be more or less useful in these different settings. An exercise electrocardiogram, for example, can be used as a diagnostic test for coronary disease, a prognostic test for patients with recent myocardial infarction, a monitoring test to assess the effect of anti-ischemic therapy, or even as a way to establish target heart rates for an exercise training program. The efficacy and cost effectiveness of applying the exercise electrocardiogram will be different for these varied uses of the information provided by the test. The value of the test will depend on the indication for which it is used, much as the value of a (3 blocker will vary whether it is used to treat hypertension or as secondary prevention after a myocardial infarction.

Risk stratification in the acute phase of coronary syndromes

Ventricular fibrillation, the major determinant of risk in the acute phase, requires immediate electrical cardioversion to avoid death. Because it is largely unpredictable, electrocardiographic monitoring and ready access to a defibrillator are the most important management strategies for saving lives in acute coronary syndromes. Also important is antithrombotic treatment which should be given to all patients acutely, with daily aspirin continuing thereafter. In other respects, management in the acute phase of coronary syndromes is largely determined by the perceived risk as judged by clinical, electro-cardiographic, metabolic, and biochemical factors.

Decision analysis in the evaluation of specific products

Assumed that low-osmolality contrast media reduced the risk of myocardial infarction and stroke. Reduction in the risk of specific clinical events with low-osmolality contrast media was assumed to be 0 in fatal events, 25 in severe events, 80 in moderate events and 10 in minor events. The investigators found that the incremental cost per QALY gained with these media was 17 264 in high-risk patients and 47874 in low-risk patients for a third-party payer. From a societal perspective, the corresponding costs are 649 and 35 509. The authors report that these estimates were sensitive to cost of the contrast media and the total cost of contrast media used per patient. The authors also suggest that the model is extremely sensitive to changes in assumptions regarding the efficacy of low-osmolality contrast media for the prevention of severe reactions. To allow the reader to better understand the inputs of this model, the authors include a cost-consequence analysis of the program as a separate...

Use of decision analysis in treatment strategies

Grade A1a The authors developed a Markov model that incorporated current American College of Cardiology American Heart Association guidelines, baseline data from a meta-analysis of randomized trials of the two therapies, and risk reduction data from randomized trials and meta-analyses. The outcome measures of interest were 5 and 10 year mortality, as well as incidence of non-fatal myocardial infarction. The authors conducted a base-case analysis of the two therapies, which they supplemented with annual fixed transition probabilities to account for a steady linear increase in mortality observed in the meta-analysis. They also conducted two subgroup analyses, one to examine 5 year mortality and infarction rates for patients with triple vessel disease, the other to examine the same outcomes for patients with impaired left ventricular function. In the base-case and subgroup analyses, the authors found that both therapies increased overall and infarction-free survival. The relative...

Left ventricular function

Left ventricular function is one of the major determinants of long term risk. There is now clear evidence that specific treatment with angiotensin converting enzyme (ACE) inhibitors (probably also P blockers) can reduce that risk, and coronary bypass surgery may be particularly beneficial when left ventricular dysfunction is associated with multivessel coronary artery disease. For many patients clinical criteria are sufficient to exclude significant left ventricular dysfunction, and an analysis of data from the GUSTO 1 trial confirmed that in patients presenting with a first infarct, absence of anterior infarction, left bundle branch block, or acute phase pulmonary oedema accurately Figure 4.3. Kinetics of creatine kinase (CK) release (left) and ST resolution (right) in response to coronary reperfusion. Sequential coronary arteriograms 90 minutes apart in 41 patients presenting with acute coronary syndromes and ST elevation permitted identification of three groups group 1 patency of...

David Naylor David A Alter

By definition this chapter demands a different treatment than later chapters where it is possible to provide integrative summaries of evidence to inform contemporary practice or steer future research. Since our focus is on how evidence is translated into clinical action, it stands to reason that there will seldom be one right answer. Practice will instead be shaped not just by evidence, but by values and circumstances or context. Thus, it is important for the reader to suspend judgment as to whether there is necessarily one right health system, or one right profile of services for all populations with a given cardiovascular condition. A corollary of this point is that hundreds of descriptive and analytical studies have been published in cardiovascular health services research, many of which are context-specific. Our hope is to use a small number of these studies to heighten the reader's understanding of analytical principles and general lessons. For consistency, the examples will...

Data sources and collection

Prospective primary data collection is costly but crucial for complex variables that are poorly covered in most secondary data sources - for example, patients' quality of life and psychosocial status. Retrospective primary data collection through chart reviews is also possible, but can be costly and time-consuming. It is best focused on routinely-recorded variables. For example, in charts of patients hospitalized with acute myocardial infarction (AMI), data on variables such as presenting symptoms, heart rate, blood pressure, ECGs, and cardiac enzymes are almost uniformly recorded. Absent primary data collection, there is always a risk that researchers will frame their questions around convenient access to data rather than addressing pressing issues.

Practical recommendations

In patients with acute coronary syndromes, management should be risk based from the time of arrival in the emergency room (fig 4.5). An ECG and troponin assay should be obtained immediately with repeat troponin assay at 12 hours.15 Patients with regional ST change (elevation or depression) or left bundle branch block are a high risk group requiring admission to the coronary care unit and appropriate antithrombotic treatment. Patients with an ECG that is normal, or shows non-diagnostic T wave changes, should be treated similarly if troponin assay is positive, but if troponins are negative at 12 hours further management should be guided by the results of a stress test. An abnormal stress test requires further cardiac investigation and treatment, but if the stress test is normal then risk is very low, permitting early discharge pending review of the diagnosis. Regardless of the hospital course, all patients should receive secondary prevention with aspirin and, when possible, P blockers....