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The independent contribution of age, sex, duration of hypertension, heart rate, clinic and ambulatory blood pressure and echocardiographic left ventricular mass to left ventricular diastolic filling abnormalities in essential hypertension was investigated in 250 subjects (145 untreated and unselected hypertensives and 105 healthy normotensive controls) undergoing Doppler and standard echocardiography and non-invasive 24-h ambulatory blood pressure monitoring. Late and early diastolic transmitral peak flow velocities and their ratio (all P less than 0.01), the rate of deceleration of early diastolic mitral flow (P less than 0.01) and the time of deceleration of early diastolic mitral flow (P = 0.018) were abnormal in the hypertensive group vs controls. None of these parameters significantly varied in the presence vs absence of LV hypertrophy. In the hypertensive group, the prevalence of abnormal age-corrected Doppler values varied up to 46% (up to 45.4% and 50% in the absence and presence of left ventricular hypertrophy, respectively; P = n.s.). In a stepwise multivariate regression analysis, age and average daytime or night-time ambulatory blood pressure showed a significant independent relationship with each of these Doppler indexes of left ventricular diastolic filling. Late transmitral peak flow velocity and the ratio of late to early peak flow velocity were also independently affected by the heart rate. Sex, duration of hypertension, clinic systolic and diastolic blood pressure and left ventricular mass index did not show any independent relationship to these Doppler parameters of left ventricular filling. In conclusion, Doppler abnormalities of diastolic transmitral blood flow were detected in up to 46% of patients in an unselected hypertensive population with a low prevalence (14.5%) of left ventricular hypertrophy. Age and ambulatory blood pressure, but not sex, duration of hypertension, clinic blood pressure and left ventricular mass itself, were the major independent determinants of these abnormalities.

The antianginal properties and the duration of action of two doses of felodipine, a dihydropyridine calcium antagonist with a vascular:myocardial potency ratio approximating 100:1, were investigated in 15 patients suffering from disabling effort angina pectoris with reproducible exercise tolerance. Felodipine (5 mg, 10 mg) and placebo were administered once in the morning on three different days, with a 24 h interval between them, according to a double-blind 3 x 3 latin square design, 5 times replicated. Symptom-limited cycloergometric exercise tests were performed 3 and 12 h after administration. Duration of exercise to ST segment depression of 1 mm and to peak exercise was increased (all P less than 0.01) by both doses of felodipine in comparison with placebo. Twelve hours after administration, the 10-mg dose induced a significant improvement in the exercise time and a smaller ST segment depression (all P less than 0.01) in comparison with the 5-mg dose. The relationship between ST segment depression and the pressure-rate product during exercise was favourably influenced by the 10-mg dose at 3 and 12 h after intake, and by the 5-mg dose only at 3 h after intake. These findings suggest an increase in coronary blood flow induced by felodipine. Apart from mild headache there were no other unwanted effects. In conclusion, felodipine improves exercise tolerance and reduces electrocardiographic ischaemia for up to 12 h after single oral administration in patients with effort angina. Increasing the dose from 5 mg to 10 mg produces a more prolonged effect, with increased exercise tolerance 12 h after intake.