CALCIUM-ANTAGONIST DRUGS IN HYPERTENSIVE PATIENTS WITH ANGINA-PECTORIS

Arterial hypertension frequently occurs in association with myocardial ischaemia and is an independent and significant risk factor for the d evelopment of coronary artery disease (CAD), as is left ventricular hy pertrophy due to arterial hypertension. The prevalence of CAD in patie nts with hypertension is high, while hypertension occurs in approximat ely 60% of patients with CAD. Myocardial ischaemia occurs both in the presence and absence of CAD, probably as the result of limitation of c oronary vasodilator capacity and reduction in coronary flow. This may occur in hypertension due to increased transmural coronary artery resi stance, alterations in the vascular wall and endothelial dysfunction. Furthermore, left ventricular hypertrophy itself predisposes the heart towards ischaemia due to an increased diffusion distance between capi llaries. When myocardial ischaemia occurs in hypertensive patients, 90 % of all episodes are asymptomatic. The highest incidence of ischaemic episodes appears to occur in treated elderly hypertensive men with in adequate blood pressure control (40%). Calcium antagonists exert a ran ge of beneficial effects in hypertensive patients, including reduction of blood pressure, improvement in myocardial blood flow, regression o f left ventricular hypertrophy and cardioprotection in reperfused orga ns. However, while vasoprotective effects have been demonstrated in an imal models, beneficial effects in man are uncertain. Thus, in establi shed coronary atherosclerosis, calcium antagonist treatment has produc ed only a mild reduction in the appearance of new atherosclerotic lesi ons.