Contrasting effects of verapamil and amlodipine on cardiovascular stress responses in hypertension

Aims To compare the effects of two long-acting calcium antagonists of different types on cardiovascular,tress responses in hypertension.Methods One-hundred and forty-five patients with mild to moderate hypertension and a mean (+/- s.e.mean) age of 51 +/- 0.9 years received for 8 weeks the phenylalkylamine verapamil sustained release (240 mg) and the dihydropyridine amlodipine (5 mg) in a double-blind cross-over design, both after 4 weeks of placebo. Blood pressure, heart rate and plasma noradrenaline were monitored during 3 min of sustained isometric handgrip and 2 min of cold pressor.Results Blond pressure was equally reduced by both drugs. After 3 min handgrip, systolic blood pressure. heart rate and rate-pressure product were lower with verapamil compared with amlodipine. Verapamil attenuated the increases in systolic blood pressure (25 +/- 2 vs 30 +/- 2 mmHg, difference 4.6, 95% CI (1.0, 8.1), P <001) and rate-pressure product (3.1 +/- 0.2 vs 3.6 +/- 0.3 x 10(3) mmHg x beats min(-1) difference 0.5, 95' ', Cl (0.1, 0.9) PConclusions Verapamil is more effective in reducing blood pressure And rate-pressure product responses to stress compared with amlodipine. Although plasma noradrenaline is lower with verapamil at rest and after stress, the increase during stress is not different.