Because of the visceral afferent innervation of the myocardium as well as the many confounding factors affecting the perception of ischemia, many patients with ACS will not experience chest discomfort. Up to one-third of AMIs may be silent, occurring without any reports of symptoms from the patient and discovered incidentally on routine ECG.1 Many other patients present with ischemic-equivalent symptoms, which may include one or any combination of the following: dyspnea at rest or exertion; shoulder, arm, or jaw discomfort; epigastric discomfort; nausea; light-headedness; generalized weakness; acute changes in mental status; or diaphoresis. Other atypical features associated with ischemia, particularly in women, include repetitive chest pain, pain relieved by antacids, pain unrelated to exercise, pain not relieved with rest or nitoglycerin, or palpitations without chest pain. 2 Upper abdominal discomfort, despite relief with antacids, can also be a symptom of myocardial ischemia; for patients over 50 and those with known CAO, the evaluation of abdominal pain should include an ECG. Patients predisposed to sensory impairment due to diabetes, advanced age, or altered mental status are especially likely to present in atypical ways. 3
Atypical chest pain is more common in women than in men,2 and disorders such as vasospastic and microvascular angina and mitral valve prolapse are more common in women. In women, typical angina is strongly suggestive of cardiac ischemia, and nonischemic pain is associated with a lower though not well defined likelihood of disease.
Ischemia produces different patterns of pain in women with known coronary artery disease. Chest pain at rest but not during exercise does not decrease the likelihood of disease in women as it does in men. Women with stable angina are more likely than men to have pain during rest, sleep, or stress. Risk factors for coronary artery disease in women are listed below:2
Postmenopausal, no hormone replacement Diabetes
Peripheral vascular disease
Palpitations are common symptoms that raise concern about myocardial ischemia. Palpitation may indicate dysrhythmia induced by ischemia, or the inducement of ischemia by a primary tachyarrhythmia. Palpitations are usually intermittent, and symptoms may have disappeared by the time ED evaluation occurs. The patient may describe palpitations in association with nonspecific chest discomfort or dyspnea, making evaluation difficult. The history should include questions about prescribed or over-the-counter medications or herbals; use of caffeine-containing beverages, symptoms of metabolic disorders such as hyperthroidism; and any prior individual or familial heart disease. If the clinic setting suggests hypokalemia or hypomagnesemia, electrolytes can be checked.
Was this article helpful?