Doppler echocardiographic assessment of left ventricular systolic and diastolic function in mild hypertension

Abnormalities in left ventricular (LV) wall thickness and mass have been demonstrated in patients with mild hypertension utilizing M-mode echocardiography. In addition, studies using radionuclide angiography have demonstrated abnormalities in early diastolic LV filling in asymptomatic hypertensive patients with normal ejection fraction and cardiac output. Recently, Doppler recordings of flow velocity in the ascending aorta and through the mitral valve have been shown to provide useful information about LV function. To determine whether flow abnormalities could be detected in patients with mild hypertension, we recorded Doppler aortic and mitral valve flow velocities in 21 men with mild hypertension. Casual systolic blood pressure was 147 ± 18 mm Hg (mean ± SD) and diastolic blood pressure was 96 ± 9 mm Hg. LV mass (310 ± 75 g) was elevated (i.e., above the 95% normal prediction interval) in 8 of 19 patients who underwent M-mode echocardiography; LV ejection fraction was normal in all patients (mean, 80%). As in previous studies in normal subjects, we found in these hypertensive patients an inverse correlation between age and both aortic peak flow velocity (r = -0.51, p<0.05) and transmitral early diastolic peak flow velocity (r = -0.44, p<0.05) and a positive relationship between age and mitral valve late diastolic peak flow velocity (r = 0.73, p<0.001). Compared to age-corrected normal data, the following mitral flow velocity parameters were abnormal: early diastolic deceleration time (mean, 28% above predicted normal; p<0.005), rate of deceleration of early diastolic flow velocity (mean, 14% below predicted normal; p<0.005), and late diastolic flow time (mean, 17% above normal; p<0.005). Neither aortic peak flow velocity nor mitral carly or late diastolic peak flow velocity correlated with echocardiographic LV mass or with casual or 24-hour average systolic or diastolic blood pressure. Only transmitral late diastolic flow velocity integral (area under flow velocity curve) was significantly correlated with LV mass (r = 0.54, p<0.02). We conclude that patients with mild hypertension have normal aortic and transmitral peak flow velocities despite the presence of increased echocardiographic LV muscle mass. However, Doppler evidence of LV filling abnormalities - including a diminished rate of deceleration of early diastolic transmitral flow velocity and increased early diastolic deceleration time and late diastolic flow time - can be detected in these patients.