We studied the effects of common antihypertensive regimens on autonomic cardiovascular control. We considered calcium channel antagonists (nicardipine twice a day and isradipine once a day, respectively) and also examined, as reference treatments, once-a-day atenolol and cilazapril. A noninvasive evaluation of autonomic cardiovascular profile was obtained with spectral analysis of RR interval and systolic arterial pressure variability. We studied moderate essential hypertensives before and after 2 weeks of treatment, both at rest and during active standing and mental arithmetic. All treatments reduced arterial pressure equally well; however, marked differences in spectral profiles were observed. The low-frequency spectral component of RR interval variability tin normalized units, marker of sympathetic modulation of the sinoatrial (SA) node] tended to be greater at rest and during stimuli (p <0.001) in subjects treated with dihydropyridines. No differences at rest, but striking increases of the low- frequency component of systolic arterial pressure variability were observed in nicardipine-treated patients during both standardized excitatory stimuli, suggesting a marked increase in sympathetic vasomotor drive. As to reference treatments, patients treated with atenolol displayed the lowest values, and patients treated with cilazapril (for 4 weeks) provided intermediate values. In conclusion, shorter acting dihydropyridine calcium channel antagonists may induce an exaggerated in crease in sympathetic vasomotor drive during standardized laboratory stressors.
- β-Adrenergic receptor antagonists
- Angiotensin-converting enzyme inhibitors
- Calcium channel antagonists
- Cardiovascular risk
- Sympathetic activity
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine