The authors examine the recent literature on psychological factors and sudden cardiac death and explore the mediating psychophysiological processes by which these variables may be associated. Direct evidence that psychosocial stressors and their correlates may be causally linked with sudden cardiac death in humans is not conclusive, but there is abundant convergent evidence that several physiological precursors of sudden death may be promoted by psychological challenge, especially in persons with coronary heart disease. The authors call for increased attention to the acute effects of psychological events on cardiovascular health.