The role of multiple action agents in hypertension.

A 20-year follow-up study of central hemodynamics in essential hypertension at rest and during exercise in 61 men with uncomplicated essential hypertension has clearly shown that hemodynamic disturbances depend on the age of the subjects and the severity of the hypertensive state and that a shift in the hemodynamic alterations take place over time. During 10- and 20-year follow-up, central hemodynamics changed towards a low cardiac-index (CI)-high total peripheral-resistance index (TPRI) pattern. With increasing age there was a gradual reduction in CI as well as stroke index (SI). The arteriovenous oxygen difference increased, particularly during exercise. The 20-year treatment with conventional drugs (beta-blockers and/or diuretics) did not prevent a marked increase in TPRI and a marked reduction in CI and SI in subjects initially 40-49 years of age. In recent years, beta-blockers with vasodilating activity have been introduced in the treatment of hypertension (labetalol, prizidilol, dilevalol and carvedilol). The hemodynamic effects of these compounds clearly differ from the changes induced during acute and chronic conventional beta-blocking treatment. In contrast to usual beta-blockers, these drugs reduce TPRI acutely and the reductions they produce in heart rate (HR) and CI are considerably lower. Our long-term data on labetalol (n = 15), prizidilol (n = 15) and dilevalol (n = 17) indicate a persistent reduction in TPRI and little or no decrease in exercise CI. Long-term data on carvedilol are not yet available. Approximately 70% of patients with mild to moderately severe essential hypertension achieved normal blood pressure during chronic treatment on beta-blockers with vasodilating activity.