Left Ventricular Hypertrophy in Hypertension: Prognostic and Pathogenetic Implications (The Framingham Study)

Abstract

The prevalence, incidence, determinants, and prognosis of ECG evidence of left ventricular hypertrophy (ECG-LVH) was examined in the Framingham cohort of 5209 subjects aged 30–62. In the course of 20 years of follow-up 957 subjects in the age range 45–74 developed cardiovascular disease and 856 died and the risk of cardiovascular disease and mortality in persons who developed ECG- LVH was compared to that of those who remained free of it.

The prevalence of ECG-LVH rose with age and one in ten developed some evidence of it in the first 12 years of follow-up. Only 16% with X-ray cardiac enlargement went on to develop ECG-LVH. The higher the blood pressure, the more likely was ECG-LVH to occur, and at pressures exceeding 180 mm Hg. systolic pressure, 50% developed some evidence of ECG-LVH.

ECG-LVH was an extremely lethal phenomenon, associated with an eight fold increased cardiovascular mortality, a risk triple that of hypertension alone. Within 5 years 35% of the men and 20% of the women with ECG-LVH were dead, a relative risk comparable to that associated with overt coronary heart disease (CHD).

The association of ECG-LVH with cardiovascular morbidity and mortality was not accounted for by age, blood pressure, or other associated cardiovascular risk factors. The ECG abnormality appears to identify those with a poor cardiovascular risk profile who have progressed to a compromised coronary circulation and cardiac damage. Associated risk of cardiac failure was three times higher than that of hypertension alone. Risk of strokes, coronary events, and occlusive peripheral arterial disease were all increased three fold or more. ECG-LVH must be regarded as a grave prognostic sign for mortality and an indication of serious cardiovascular disease soon to develop.