Emotional triggering of cardiac events.

Psychological factors may contribute not only to the evolution of coronary atherosclerosis and long-term risk of coronary heart disease, but also to the triggering of acute cardiac events in patients with advanced atherosclerosis. Evidence for emotional triggering of cardiac events derives both from population-based studies of hospital admissions and sudden deaths following major traumas such as earthquakes and terrorist incidents, and from individually based interview studies with survivors of acute coronary syndromes (ACS). The latter indicate that acute anger, stress and depression or sadness may trigger ACS within a few hours in vulnerable individuals. The psychobiological processes underlying emotional triggering may include stress-induced haemodynamic responses, autonomic dysfunction and parasympathetic withdrawal, neuroendocrine activation, inflammatory responses involving cytokines and chemokines, and prothrombotic responses, notably platelet activation. These factors in turn promote coronary plaque disruption, myocardial ischaemia, cardiac dysrhythmia and thrombus formation. The implications of these findings for patient care and ACS prevention are outlined.