Influence of environmental stress on pathogenesis of sudden cardiac death.

The effects of 20th-century stress on the cardiovascular system are reviewed and correlated with experimental animal models. A classic example of such stress is drawn from a study of the aerospace workers at Cape Kennedy who were shown to be exposed to excessive occupational stress. Surprisingly, the usual risk factors did not predict a greater risk, yet the population exhibited a higher incidence of sudden cardiac death and acute myocardial infarction. Acute myocardial necrosis was much more frequently demonstrated than was acute coronary obstruction of any type. Retrospective coroner's studies revealed two types of myocardial necrosis: 1) elongated, thinned or wavy fibers and 2) anomalous contraction bands. Correlation of these clinical observations with experimental data was duplicated in canine models of myocardial infarcion and/or catecholamine-induced necrosis. Catecholamines can lead to irreversible myocardial necrosis but the underlying mechanisms appear to be complex. Extrapolation of the results from the experimental and clinical studies suggests that environmental stress can lead to myocardial necrosis.