Exercise-induced modifications in cardiorespiratory parameters of hypertensive patients treated with calcium antagonists.

The effects of calcium antagonists in reducing blood pressure at rest and during exercise were examined in patients with mild-to-moderate essential hypertension. The haemodynamic effects of calcium antagonists were evaluated at rest and during exercise. We also examined 10 patients with mild-to-moderate essential hypertension taking lacidipine, a new dihydropyridine calcium antagonist (4 mg once a day, at 0700 h). Compared with placebo, lacidipine induced significant mean reductions in 24-h blood pressure (P less than 0.001 for systolic blood pressure; P less than 0.002 for diastolic blood pressure). After 24 h, the blood pressure reductions were still significant (P less than 0.02 for systolic blood pressure; P less than 0.04 for diastolic blood pressure). The heart rate did not change. During dynamic exercise, blood pressure at maximal effort was reduced (P less than 0.01 for systolic and diastolic blood pressure) and the external workload reached at the anaerobic threshold was significantly increased (P less than 0.001), but not at maximum effort. Ventilation and tidal volume were similar at both the anaerobic threshold and peak exercise, while oxygen uptake and carbon dioxide production were increased at the anaerobic threshold (P less than 0.02 for carbon dioxide production) but were similar at peak exercise.