Effects of antihypertensive drugs on SBP variability are dose-dependent and persist when used in combinations .
Use of a high dose of a calcium channel blocker alone or in combination with other agents is therefore likely to be particularly effective in prevention of stroke
BACKGROUND AND PURPOSE Recent studies have shown that visit-to-visit blood pressure variability is a powerful risk factor for stroke , is reduced by calcium channel blockers and diuretics , and increased by β-blockers .
However , it is unknown whether these effects are dose-dependent and persist in combination with other drugs .
Cardiovascular responses to verapamil and propranolol in hypertensive patients.
Since there is concern that the potentially useful antihypertensive combination of verapamil and propranolol might lead to adverse cardiovascular responses , we have investigated its effects , not only on blood pressure , but also on electrocardiographic and echocardiographic variables .  Fourteen hypertensive patients participated in a double-blind , r and omized , crossover comparison of verapamil 360 mg , propranolol 240 mg , verapamil 360 mg + propranolol 240 mg , and placebo , each given for 4 weeks . The antihypertensive effect of verapamil + propranolol was greater than that of either drug alone . Pulse rate was reduced by propranolol but not verapamil . However , addition of verapamil to propranolol led to further reduction in pulse rate . The PR interval was prolonged by verapamil + propranolol when compared with all other treatments . The active drugs increased ventricular dimensions and the effect of the combination was statistically significant . Thus , verapamil + propranolol is an effective antihypertensive combination , but heart rate , atrio-ventricular conduction and left ventricular function may be affected adversely , necessitating careful monitoring of therapy
Effects of antihypertensive drugs on SBP variability are dose-dependent and persist when used in combinations .
Use of a high dose of a calcium channel blocker alone or in combination with other agents is therefore likely to be particularly effective in prevention of stroke
BACKGROUND AND PURPOSE Recent studies have shown that visit-to-visit blood pressure variability is a powerful risk factor for stroke , is reduced by calcium channel blockers and diuretics , and increased by β-blockers .
However , it is unknown whether these effects are dose-dependent and persist in combination with other drugs .