Risk factors in elderly hypertensives: Recent large-scale clinical trials have shown that antihypertensive treatment in the elderly produces meaningful reductions in strokes and other cardiovascular events. However, the treatment of hypertension in older patients is often complicated by the presence of concomitant disorders. Clinical and silent myocardial ischemia, as well as left ventricular hypertrophy and both systolic and diastolic left ventricular dysfunction, frequently coexist with hypertension. Additional clinical considerations in elderly hypertensives include a high prevalence of abnormal lipid and glucose metabolism and a tendency toward decreased renal function.
Effects of different antihypertensive drugs: Although diuretics and conventional [beta]-blockers have been used as first-line drugs in the major clinical trials, some of their effects on metabolic parameters and on the myocardium can make them inappropriate in some patients. Newer drug classes, including angiotensin converting enzyme (ACE) inhibitors, calcium-channel blockers and, more recently, [alpha]-adrenergic blockers are effective alternatives. Dual-acting [beta]-blockers offer an important new approach for treating hypertension in elderly patients.
Effects of carvedilol: Carvedilol possesses both [beta]- and [alpha]1-blocking activity and appears to exhibit calcium channel blocking activity in animals. The [alpha]1-blocking properties of this drug help to produce a desirable hemodynamic profile and facilitate appropriate blood pressure and heart rate responses to exercise. Carvedilol does not appear to adversely affect left ventricular systolic function and, in selected patients with heart failure, has been shown to increase the ejection fraction. Although this effect on ventricular function has yet to be fully defined, carvedilol clearly increases exercise duration and time-to-angina during treadmill testing in patients with ischemic heart disease. The [alpha]1-blocking properties of this agent also offset unwanted [beta]-blocking effects on lipid and glucose metabolism. Thus, carvedilol is emerging as a dual-acting agent with a potentially wide application in the management of elderly hypertensive patients with concomitant disorders.
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