Intraventricular dispersion of E wave velocity: an alternative measure of left ventricular diastolic function in hypertensive patients?

Abstract

The E/A ratio (of peak mitral blood flow velocity during early diastole to that during atrial contraction) has limitations in the assessment of diastolic function. Previous studies have suggested that peak blood flow velocity is normally maintained or increased towards the cardiac apex but that it decreases in diastolic dysfunction. We evaluated the proposal that intraventricular dispersion of E wave velocity is an effective means of assessing diastolic function in hypertensives. Fifty-five untreated hypertensive patients underwent echocardiographic examination. Pulsed-wave Doppler recordings were made from the apical four-chamber view. Peak flow velocities were measured during early diastole at the level of the mitral valve (E₀), and 3 cm distally (E₃), and during atrial contraction at the level of the mitral valve (A). Mean peak flow velocities were 64.4 ± 16.1 m/s for E₀, 50.6 ± 17.9 m/s for E₃ and 61.1 ± 12.1 m/s for A. Peak flow velocity during early diastole slowed towards the cardiac apex in most patients (E₃/E₀ range: 0.42–1.86, mean 0.81 ± 0.29). There was no significant difference in E₃/E₀ between those with and without left ventricular hypertrophy (LVH) (0.76 ± 0.25 vs 0.82 ± 0.29, P = 0.39). E₃/E₀ did not correlate with age (r = −0.02, P = 0.89), systolic blood pressure (BP) (r = 0.17, P = 0.20), diastolic BP (r = 0.21, P = 0.12) or LVMI (r = −0.11, P = 0.40). In contrast the E/A ratio correlated strongly with age (r = −0.66, P < 0.0001) and negatively, though not significantly, with systolic bp (r = −0.24, P = 0.07), diastolic BP (r = −0.23, P = 0.09) and LVMI (r = −0.23, P = 0.08). Although there is some intraventricular dispersion of E wave velocity in this group of hypertensive patients, the ratio of E₃/E₀ correlates poorly with parameters which are known to influence diastolic function. In spite of its limitations, the E/A ratio appears to be a more reliable measure of diastolic function in hypertensive heart disease than intraventricular dispersion of early diastolic filling.