Treatment of Essential Hypertension with a New Vasodilator in Combination with Beta-Adrenergic Blockade

Abstract

A new piperidino-pyrimidine vasodilator (PDP) when used in the treatment of 11 hypertensive patients, lowered blood pressure from 188/124 to 159/100 over six to seven days. blood-pressure responses to standing, cold-pressor test and Valsalva maneuver persisted, and postural symptoms did not occur despite marked reduction of blood pressure. However, the antihypertensive action was associated with reflexly induced increases in heart rate, cardiac index and norepinephrine excretion and evidence of myocardial ischemia in some patients. Selective beta-adrenergic blockade with propranolol prevented this augmentation of cardiac activity and further decreased blood pressure. Although glomerular filtration rate and renal plasma flow were unchanged, sodium retention occurred in all patients. Such retention appeared to be readily controllable with oral diuretics in the one patient to whom it was given. Thus, PDP combined with propranolol results in highly effective lowering of blood pressure in hypertensive patients without attendant postural symptoms, and may provide an important new approach to antihypertensive therapy.