THE RELATION BETWEEN LEFT-VENTRICULAR MASS AND PROGNOSIS IN HYPERTENSION

Echocardiographic measurement of left ventricular mass has provided a way of evaluating the undesirable effects of high blood pressure on the heart in the same way as for obesity, excess salt intake and blood hyperviscosity. Recently, the left ventricular mass was shown to correlate (r = 0.81) with the hemodynamic stimuli of blood pressure, stroke volume and left ventricular contractility. Prospective trials at Cornell and Framingham indicate that left ventricular mass is a powerful predictive factor of the risk of complications in hypertension. In the first of these trials, we demonstrated in a 5 year follow-up study of 140 men with uncomplicated hypertension that the incidence of death, myocardial infraction or angina requiring myocardial revascularisation, was four times greater in patients with increased left ventricular mass and that this association was independant of the blood pressure levels. Then, in a 10 year follow-up study of hypertensive patients of both sexes, we established that the left ventricular mass was the most powerful predictive factor of mortality and morbidity and that this was so marked (15 % death rate in subjects with LVH vs 1 % in subjects with normal left ventricular mass-p < 0.00001 -, cardiovascular accidents in 26 % of subjects with LVH compared with 12 % in subjects with normal left ventricular mass - p < 0.0001) that only left ventricular mass and age were independant predictive factors of morbid events in multiple variable analysis. In the Framingham study, the frequency of coronary events in a 4 year follow-up period of healthy subjects from the original cohort (average age 69 years) was significantly related to the left ventricular mass and independant of other risk factors. This relationship was even more striking in hypertensive subjects whose 4 year incidence of morbid events was much greater in the 25 % with the highest left ventricular mass than in the 25 % with the lowest left ventricular mass in both sexes (men: 20 % vs 3 %; women: 11 % vs 2 %). More recently, it has been shown that left ventricular mass also allows prediction of the risk of death, independantly of the classical risk factors in middle age subjects as in the more elderly Framingham population. Therefore, the left ventricular mass allows an assessment of the undesirable effects of hypertension and other stimuli on the heart and provides a means of evaluating the prognosis in hypertension. The left ventricular mass would seem to be a better way of predicting the complications of hypertension than the blood presure or the other risk factors.