Relax Your Mind

Relaxation Techniques

Get Instant Access

Color Mode
Fig. 14. Color M-mode flow propagation velocity. Color M-mode propagation velocities in a patient with normal (left) and abnormal (right) diastolic function. Vp, color M-mode color flow propagation velocity (normal Vp [cm/s] > 45; diastolic dysfunction < 45).

Novel Uses of DTI

In addition to assessing diastolic function, Ea velocities can be used to estimate LV filling pressures, to discriminate between constrictive pericarditis and restrictive cardiomyopathy, and to differentiate athlete's heart from hypertrophic cardiomyopathy (HCM).

Estimation of LV Filling Pressures

Several investigators have performed simultaneous cardiac catheterization and echocardiography studies to estimate LV filling pressures using the ratio of the mitral inflow E-wave and the tissue Doppler Ea-wave. Different regression formulas have been proposed to calculate either LV end diastolic pressure (LVEDP) or pulmonary capillary wedge pressure. Perhaps more practical than specific regression formulae is the correlation with the ratio of E/E alone.

E/Ea more than 10-15 correlates with an elevated LVEDP (>12 mmHg).

E/E less than 8 correlates with a normal LVEDP.

Differentiation Between Constrictive and Restrictive Physiology

With both constrictive pericardititis and restrictive cardiomyopathy, there is abnormal LV filling. With constrictive physiology, extrinsic factors (pericardial constraint) impede normal filling of the LV. In the case of restrictive cardiomyopathy, abnormal filling is secondary to factors intrinsic to the myocardium that cause impaired relaxation and decreased compliance. Ea velocities with constrictive pericarditis in the absence of coexistant myocardial pathology are typically normal. In contrast, Ea velocities in restrictive cardiomyopathy are typically reduced (see Chapter 9, Fig. 13).

Differentiation of Athletes' Hearts From HCM

Approximately 2% of elite athletes may have an increased LV wall thickness, raising the potential diagnosis of HCM. It can be clinically challenging to discriminate the physiologic hypertrophy that results from intense athletic conditioning from pathological hypertrophy. Recent studies incorporating measurement of Ea velocities may be helpful in making this differentiation. Athletes typically have brisk Ea velocities, reflective of a highly compliant LV, whereas individuals with HCM typically have reduced Ea velocities owing to decreased LV compliance and impaired LV relaxation (see Chapter 9, Table 14).

Color M-Mode

Color M-mode Doppler imaging from the apical four-chamber window is an alternative method to relate mitral inflow to LV relaxation, again in a less load-dependent manner than standard transmittal Doppler. The velocity of propagation of flow (Vp) from the LV base toward the apex is measured in early diastole. The slope of this flow signal is thought to represent the LV intraventricular gradient, influenced by active recoil (suction forces) and relaxation. This is accomplished by measuring the slope of the leading edge of flow (the transition from black to color) or an isovelocity line (e.g., the first aliasing velocity line). Normal Vp exceeds 55 cm per second. Vp less than 45 cm per second is thought to indicate impaired relaxation. In real practice, precise measurement of Vp has proven challenging, thus the most common application of this technology is as a qualitative measure of diastolic function. If the Vp slope appears nearly upright by visual estimate, this is an indication of preserved diastolic function. If the Vp slope appears quite blunted, this indicates impaired diastolic function (Fig. 14).

comprehensive echocardiography assessment of diastolic function

Accurate assessment of diastolic function requires the assessment of multiple parameters. By integrating information gleaned from mitral inflow patterns, PV flow, and TDI, as well as looking for surrogate evidence of decreased LV compliance, such as left ventricular hypertrophy or LA enlargement, the overall state of LV diastolic function may be best evaluated (Table 3).

Diastolic Function Assessment Algorithm

1. Assess overall LV and RV systolic function from two-dimensional images. "Yes" answers increase the likelihood of diastolic dysfunction.

a. Are chamber sizes normal?

i. Is LA enlargement seen?

ii. Is LVH present?

iii. Is LV systolic function abnormal?

b. Standard Doppler interrogation of mitral inflow and PV flow.

i. If mitral inflow appears normal, integrate the above information and assess the PV flow pattern to differentiate from a pseudonormal pattern.

a d. Color M-mode of mitral inflow with qualitative assessment of Vp.

e. If further investigation is required, consider:

i. Assessment of mitral filling patterns in response to alterations in loading conditions (administration of sublingual nitroglycerin to decrease preload or passive leg raising to increase preload).

ii. Response to exercise.

iii. Estimation of LV filling pressures using E/Ea.

iv. Measurement of IVRT.

suggested reading

Appleton CP, Hatle LK, Popp RL. Relation of transmitral flow velocity patterns to left ventricular diastolic function: new insights from a combined hemodynamic and Doppler echocardio-graphic study. J Am Coll Cardiol 1988;12:426-440. Appleton CP, Jensen JL, Hatle LK, Oh JK. Doppler evaluation of left and right ventricular diastolic function: a technical guide for obtaining optimal flow velocity recordings. J Am Soc Echocardiogr 1997;10:271-292.

Cardim N, Oliveira AG, Longo S, et al. Doppler tissue imaging: regional myocardial function in hypertrophic cardiomyopathy and in athlete's heart. J Am Soc Echocardiogr 2003; 16: 223-232.

Cohen GI, Pietrolungo JF, Thomas JD, Klein AL. A practical guide to assessment of ventricular diastolic function using Doppler echocardiography. J Am Coll Cardiol 1996;27:1753-1760.

Drazner MH, Hamilton MA, Fonarow G, Creaser J, Flavell C, Stevenson LW. Relationship between right and left-sided filling pressures in 1000 patients with advanced heart failure. J Heart Lung Transplant 1999;18:1126-1132.

Farias CA, Rodriguez L, Garcia MJ, Sun JP, Klein AL, Thomas JD. Assessment of diastolic function by tissue Doppler echocardiography: comparison with standard transmitral and pulmonary venous flow. J Am Soc Echocardiogr 1999; 12:609-617.

Garcia MJ, Rodriguez L, Ares M, Griffin BP, Thomas JD, Klein AL. Differentiation of constrictive pericarditis from restrictive car-diomyopathy: assessment of left ventricular diastolic velocities in longitudinal axis by Doppler tissue imaging. J Am Coll Cardiol 1996;27:108-114.

Garcia MJ, Thomas JD, Klein AL. New Doppler echocardiography applications for the study of diastolic function. J Am Coll Cardiol 1998;32:865-875.

Giannuzzi P, Imparato A, Temporelli PL, et al. Doppler-derived mitral deceleration time of early filling as a strong predictor of pulmonary capillary wedge pressure in postinfarction patients with left ventricular systolic dysfunction. J Am Coll Cardiol 1994;23:1630-1637.

Nagueh SF, Middleton KJ, Kopelen HA, Zoghbi WA, Quinones MA. Doppler tissue imaging: a noninvasive technique for evaluation of left ventricular relaxation and estimation of filling pressures. J Am Coll Cardiol 1997;30:1527-1533.

Nagueh SF, Lakkis NM, Middleton KJ, Spencer WH, 3rd, Zoghbi WA, Quinones MA. Doppler estimation of left ventricular filling pressures in patients with hypertrophic cardiomyopathy. Circulation 1999;99:254-261.

Nishimura RA, Tajik AJ. Evaluation of diastolic filling of left ventricle in health and disease: Doppler echocardiography is the clinician's Rosetta Stone. J Am Coll Cardiol 1997;30:8-18.

Pinamonti B, Zecchin M, Di Lenarda A, Gregori D, Sinagra G, Camerini F. Persistence of restrictive left ventricular filling pattern in dilated cardiomyopathy: an ominous prognostic sign. J Am Coll Cardiol 1997;29:604-612.

Rakowski H, Appleton C, Chan KL, et al. Canadian consensus recommendations for the measurement and reporting of diastolic dysfunction by echocardiography: from the Investigators of Consensus on Diastolic Dysfunction by Echocardiography. J Am Soc Echocardiogr 1996;9:736-760.

Sohn DW, Chai IH, Lee DJ, et al. Assessment of mitral annulus velocity by Doppler tissue imaging in the evaluation of left ventricular diastolic function. J Am Coll Cardiol 1997;30: 474-480.

Yamada H, Oki T, Mishiro Y, Tabata T, et al. Effect of aging on dias-tolic left ventricular myocardial velocities measured by pulsed tissue Doppler imaging in healthy subjects. J Am Soc Echocardiogr 1999;12:574-581.

Yamamoto K, Nishimura RA, Chaliki HP, Appleton CP, Holmes DR, Jr., Redfield MM. Determination of left ventricular filling pressure by Doppler echocardiography in patients with coronary artery disease: critical role of left ventricular systolic function. J Am Coll Cardiol 1997;30: 1819-1826.

Was this article helpful?

0 0
Relaxation Audio Sounds Dusk At The Oasis

Relaxation Audio Sounds Dusk At The Oasis

This is an audio all about guiding you to relaxation. This is a Relaxation Audio Sounds with sounds from Dusk At The Oasis.

Get My Free MP3 Audio

Post a comment