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Calcium antagonists in the treatment of arterial hypertension
1Centro di Fisiologia Clinica e Ipertensione, Ospedale Maggiore, Cattedra di Medicina Interna, Milano, Italy.
Insights
Calcium antagonists effectively lower blood pressure and vascular resistance. Newer dihydropyridine types offer sustained 24-hour control, without disrupting neural circulation control.
Area of Science:
- Pharmacology
- Cardiovascular Medicine
- Hypertension Management
Background:
- Calcium antagonists are established antihypertensive medications.
- Their primary hemodynamic effects include reduced blood pressure and peripheral vascular resistance.
- Short-term use may cause a reflex increase in heart rate and cardiac output.
Purpose of the Study:
- To evaluate the effects of calcium antagonists on hemodynamic parameters and neural circulation control.
- To investigate the baroreflex function during calcium antagonist administration.
- To assess the characteristics of new dihydropyridine calcium antagonists, focusing on vascular selectivity and sustained blood pressure reduction.
Main Methods:
- Review of hemodynamic effects of calcium antagonists.
- Analysis of changes in central and reflex neural control of circulation.
- Assessment of baroreflex function modifications.
- Evaluation of new dihydropyridine calcium antagonists using ambulatory blood pressure monitoring.
Main Results:
- Calcium antagonists reduce blood pressure and peripheral vascular resistance.
- They do not negatively interfere with central and reflex neural circulation control.
- Baroreflex function is reset towards lower blood pressure values.
- Newer dihydropyridines show enhanced vascular selectivity and provide sustained 24-hour blood pressure reduction with single oral doses.
Conclusions:
- Calcium antagonists are effective antihypertensives with beneficial effects beyond blood pressure reduction.
- They maintain neural circulatory control, with baroreflex resetting as a key adaptation.
- Advanced dihydropyridine calcium antagonists offer improved efficacy and convenience through sustained action.
Abstract:
Calcium antagonists are widely used antihypertensive agents whose hemodynamic effects consist of a reduction in blood pressure and peripheral vascular resistance that is associated, in case of short-term administration, with a reflex increase in heart rate and cardiac output. These compounds exert several additional positive effects besides blood pressure reduction. Among them, calcium antagonists exert their antihypertensive effect without negatively interfering with both central and reflex neural control of circulation. The only change in baroreflex function observed during the administration of these compounds is a resetting of the baroreflex toward the lower blood pressure values achieved by treatment. New calcium antagonists of the dihydropyridine type are characterized by a greater vascular selectivity, and by the ability to exert a persistent blood pressure reduction throughout the 24 hours when administered in a single oral dose. The latter feature can be properly assessed by means of ambulatory blood pressure monitoring techniques.