Acute and Short-term Effect of Amlodipine on Left Ventricular Diastolic Function Measured by Transmitral and Pulmonary Venous Flow Velocities in Subjects with Essential Hypertension

We evaluated both the effect of 5 mg single-dose oral amlodipine during the peak effect time and at the end of a short-term period of 4 weeks on left ventricular diastolic function measured by transmitral and pulmonary venous flow velocities and the antihypertensive efficacy and tolerability in 25 patients with mild to moderate essential hypertension. Pulse and blood pressure measurements and echocardiographic assessment by standard techniques were performed at baseline, peak effect time and at the end of the 4-week short-term period. Amlodipine affecting the small and large arteries reduced both the total peripheral vascular resistance and pulse pressure/stroke volume rate (p<0.001, p<0.01, respectively) during the peak effect time and at the end of the 4-week short-term period. Thus, it increased the arterial distensibility while causing significant decrease in systolic, diastolic and mean blood pressure (p<0.001, p<0.001 and p<0.01 respectively). It had no effect on heart rate, stroke volume and cardiac output. It was observed that amlodipine did not affect diastolic filling parameters which had been assessed by transmitral flow velocities during the peak effect time and at the end of the 4-week short-term period. No change on systolic and diastolic pulmonary venous flow was observed. However, significant decrease in reverse pulmonary flow was recorded. In conclusion, the acute and short-term effects of amlodipine in moderate to mild hypertension caused significant increase in arterial distensibility and signifiant decrease in blood presure. However, it had no effect on heart rate, stroke volume and cardiac output. It affected only the reverse pulmonary flow.