Cardiac failure and sudden death in the Framingham Study

Mortality is examined in patients with cardiac failure in the Framingham study of 5209 subjects. During 30 years of follow-up, the incidence of cardiac failure doubled with each decade of age with a male predominance produced by higher rates of coronary heart disease. Most cardiac failure was associated with hypertension or coronary heart disease. Among 232 men and 229 women in whom cardiac failure developed, sudden death occurred at nine times the general age-adjusted population rate. Cardiac failure alone increased the risk of sudden death fivefold. In those who also had coronary heart disease there was a further doubling of risk. The major predisposing factors for cardiac failure included hypertension, obesity, glucose intolerance, heavy smoking, cardiac enlargement, ECG abnormality, and atrial fibrillation. These were also risk factors for sudden death. These shared modifiable risk factors and cardiac impairments did not entirely account for the markedly increased risk of sudden death in cardiac failure. This suggests that either the damaged myocardium or treatment needed to control the cardiac failure may be at fault.