Left ventricular hypertrophy as a risk factor in arterial hypertension.

Data on the evolution and prognostic implications of left ventricular hypertrophy (LVH) determined by ECG, chest X-ray and echocardiogram in the Framingham Study are reviewed. Echocardiographic examination provides the most sensitive and specific measure of left ventricular hypertrophy, providing a quantitative evaluation of the anatomical condition. Chest X-ray evaluation is also more sensitive than the ECG, but less specific than the echocardiogram. When ECG-LVH is present, X-ray and echocardiographic LVH are often found; but, when negative, the ECG clearly does not exclude anatomical LVH. The incidence of each variety of LVH increases with age, weight and blood pressure. Although it may also appear following coronary heart disease (CHD), valvular deformity and congenital cardiac defects, the former are the major determinants of LVH in the general population. Each contributes independently to the occurrence of LVH. LVH has emerged as a powerful non-invasive indicator of increased vulnerability to the occurrence of major cardiovascular disease outcomes in hypertension. It appears that X-ray and echocardiographic LVH measure anatomical hypertrophy, whereas the ECG variety is also indicative of ischaemic myocardial involvement when repolarization abnormality is present. Hypertension clearly predisposes to both anatomical and ECG-LVH which cannot be taken as an incidental compensatory feature since at any blood pressure those with ECG-LVH, X-ray or echo LVH are distinctly more prone to cardiovascular sequelae. ECG-LVH carries a greater risk than anatomical (X-ray) LVH. ECG-LVH with repolarization abnormality is more dangerous than that with voltage alone. The latter appears to reflect chiefly the severity and duration of accompanying hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)