Trends in Australian heart disease mortality were assessed for association with the business cycle. Correlation models of mortality and unemployment series were used to test for association. An indicator series of "national stress" was developed. The three series were analyzed in path models to quantify the links between unemployment, national stress, and heart disease. Ischemic heart disease (IHD) mortality and national stress were found to follow the business cycle. The two periods of accelerating IHD mortality coincided with economic recession. The proposed "wave hypothesis" links the trend in IHD mortality to the high unemployment of severe recession. The mortality trend describes a typical epidemic parabolic path from the Great Depression to 1975, with a smaller parabolic trend at the 1961 recession. These findings appear consistent with the hypothesis that heart disease is, to some degree, a point source epidemic arising with periods of severe economic recession. Forecasts under the hypothesis indicate a turning point in the mortality trend between 1976 and 1978. (Am J Public Health 69:772-781, 1979).