Chance and sudden death.

An aura of mystery has always surrounded the subject of sudden unexpected death. Part of the explanation is an absence of a single or unusual explanation, although electrical instability of the heart does serve as a unifying concept for the final common pathway. In this review, emphasis is placed on the random aggregation of a wide variety of contributing factors in the pathogenesis of sudden death. Such factors include coronary disease, platelet aggregation, neural control of the heart, apoplexy of the heart, normal and abnormal variations in the structure of the atrioventricular junction, lessons from certain rare cardiac tumors and the nature of ventricular fibrillation. Useful thinking about these and related causes should employ both a horizontal (concurrence of events) and vertical (sequence of events) matrix, in all of which chance plays a major role. One impediment to understanding sudden death associated with coronary disease is the prevalent assumption that one is due to the other without proper examination of the other factors involved, some of which may be more susceptible to intervention or modification. The multifactorial nature of the pathogenesis of sudden death and the recognition that chance is a major determinant of which factors convene and when they will aggregate in the victim are essential elements to consider if more effective means of treatment and prevention are to be obtained.