Hypertension and coronary microvascular disease.

Abstract

Arterial hypertension represents the most frequent kind of left ventricular pressure overload in man. As former studies in our clinic have shown, three distinct types of left ventricular hypertrophy may occur: concentric — irregular — eccentric (1). The main functional features of these different types of hypertrophy imply: (I) Left ventricular systolic ejection fraction is normal, despite of significant or excessive increase in left ventricular muscle mass as long as ventricular volume is not increased. Diastolic function is impaired at all stages of LV hypertrophy. (II) There is an inverse relationship between systolic wall stress, i.e. left ventricular afterload, and left ventricular function. (Ill) Systolic wall stress is directly correlated with LV myocardial oxygen consumption. (IV) In hypertensive hypertrophy there is, even at normal coronary arteriogram, significant reduction in coronary reserve (2) (Fig. 1). Both, reduction in coronary reserve and diastolic dysfunction already may occur in the prehypertrophic state of hypertensive heart disease.