During the past decade, knowledge of the clinical course of coronary artery thrombosis and the pathologic changes associated with it has been increased rapidly. Nevertheless, the actual events which precipitate an attack remain a matter of speculation. Characteristically, an attack of angina pectoris follows physical exertion or emotional stress, and without critical analysis the same factors have been considered responsible for inducing coronary artery thrombosis.
Fitzhugh and Hamilton1 and others2 expressed the belief that coronary thrombosis follows unusual exertion. Riesman and Harris3 and Wolff and White4 concurred with them but pointed out that an attack often occurs while the patient is at rest or even in bed. Other authors5 found no definite relationship between physical stress and coronary thrombosis. Luten6 went so far as to state that the attack invariably occurs in the absence of effort.
Similarly, the importance of occupation and social status