Carvedilol in Hypertension

Nineteen men (mean age, 44 years) with moderately severe essential hypertension were studied invasively at rest and during exercise. After initial predrug recordings, patients received 25 mg carvedilol orally, and central hemodynamics at rest and during exercise were recorded 1 and 2 h after tablet intake to evaluate the immediate effects of carvedilol. Blood pressure decreased by 11% within 1 h, and the hemodynamic results indicated a combination beta-blocking and vasodilating effect. After 6-9 months of treatment (dose, 25-100 mg), supine hemodynamics were recorded, first 12-24 h after the last dose and then 1 and 2 h after an additional 25-mg dose. During chronic treatment (2 h after the last dose with the patient at rest and in the supine position), mean arterial pressure was reduced by 17% (p less than 0.001) and total peripheral resistance index was reduced by 6% (NS), whereas heart rate and cardiac index were reduced by 12%. Exercise hemodynamics demonstrated a decrease in blood pressure of 17% (p less than 0.001). Exercise stroke index increased by 5% (NS), in part compensating for the reduction in heart rate of 17%. Total peripheral resistance index was reduced by 5% (NS). Twenty-four-hour blood pressure monitoring (Accutracker II) demonstrated significant blood pressure reductions in awake as well as in asleep patients. Blood pressures decreased from 163/102 to 141/84 mm Hg in from 135/78 to 122/68 mm Hg in awake and asleep patients; respectively. Carvedilol is an effective antihypertensive agent, and the hemodynamic mode of action reflects alpha 1- and beta 1-blocking activities.