AGE-RELATED CARDIOVASCULAR CHANGES: Age-related changes in vascular structure and function may contribute to
isolated systolic hypertension and target-organ damage. These include
cardiac hypertrophy, systolic as well as diastolic dysfunction,
congestive heart failure,
coronary artery disease,
cardiac arrhythmias,
cerebrovascular diseases,
peripheral vascular diseases and
renal insufficiency. POTENTIAL ADVANTAGES OF
CALCIUM ANTAGONISTS IN THE ELDERLY:
Dihydropyridine calcium anatagonists have been advocated as first choice agents for the treatment of
hypertension in the elderly on the grounds that (1) they may be more active in lowering blood pressure because of the predominantly low
renin status in elderly hypertensives, (2) they may be better tolerated because side effects related to the activation of the sympathetic system may be less frequent because of attenuation of baroflexes during ageing and (3) they may have beneficial effects on a variety of concomitant
cardiovascular diseases which are frequently present in the elderly. These assumptions, however are not always proven in clinical practice. ADVANTAGES OF
NICARDIPINE: Additional to its potent vasodilatator action,
nicardipine has anti-ischemic effects in both the coronary and the cerebral circulation, including antiplatelet and hemorrheological effects, and protection at ther cellular level against
calcium overload and
ischemia. The results of a large number of studies in
cerebrovascular insufficiency suggest that
nicardipine, may favourably affect the cerebral circulation and may improve the patient's cognitive function.
Nicardipine may decrease left ventricular mass by about 4-12% and may reduce both the frequency and the severity of arrhythmias. The anti-anginal effects of
nicardipine are well established. The
drug is also able to decrease the progression of new atherosclerotic lesions in coronary arteries and is consequently potentially beneficial in elderly hypertensives with
coronary artery disease.
Nicardipine has no clinically significant negative inotropic effect. Nevertheless, in
congestive heart failure, the use of
calcium antagonists is usually not recommended because of the lack of clinical benefit and of possible harmful effects, including sympathetic and renin-angiotensin system stimulation. Although kidney protection may be provided by a strict and long-term control of blood pressure, the effects of
nicardipine on long-term protection of renal function are not clear at present. RECENT CONTROVERSY CONCERNING SHORT-ACTING
CALCIUM ANTAGONISTS: Much-debated recent case-control studies suggest that hypertensive patients treated with short-acting
calcium antagonists may have an increased incidence of
myocardial infarction and possibly of cardiovascular and total mortality. However, only well designed prospective comparative trials can answer this question.