Characterisation of left ventricular function by tissue Doppler imaging technique in newly diagnosed, untreated hypertensive subjects

BACKGROUND Hypertension results in structural and functional changes in the heart. Early detection of abnormalities of cardiac structure and function is important in the assessment and treatment of hypertensive subjects. The aim of this study was to evaluate the utility of the tissue Doppler echocardiographic technique in characterising diastolic and systolic functions in untreated native black African hypertensive subjects. MATERIALS AND METHODS Forty consecutive, newly diagnosed, untreated hypertensives with adequate conventional echocardiographic (2-D, M-mode, transmitral and pulmonary Doppler flow velocities) and tissue Doppler echocardiographic images were recruited into the study. The control subjects were apparently normal individuals. Each arm of the study consisted of 21 male and 19 female subjects. RESULTS The two groups were comparable by age (48.6 +/- 11.35 years in the hypertensives vs 48.1 +/- 11.33 years in the controls; p = 0.844) and gender distribution (M/F: 21/19 in both groups). Other baseline characteristics, except for blood pressure parameters, which were predictably higher in the hypertensive subjects, were comparable between the two groups. The hypertensive subjects had a lower systolic myocardial velocity (Sm) and early diastolic myocardial velocity (Em) in comparison with the controls (p = 0.033 and p = 0.018, respectively). The late diastolic myocardial velocity (Am) was comparable in the two groups (p = 0.430). CONCLUSIONS Tissue Doppler echocardiography demonstrates diastolic dysfunction relatively early in native African hypertensives and may be useful for detecting subtle deterioration in systolic function.