Depression, heart disease, and tricyclic antidepressants.

Concern over the cardiovascular effects of tricyclic antidepressants has been long standing. Recently there have been a number of studies of the use of tricyclics in depressed patients with preexisting cardiac disease, specifically ventricular arrhythmias, impairment of left ventricular function, and conduction disease. The results have demonstrated that tricyclics are effective Class 1A antiarrhythmic drugs and that contrary to earlier expectations tricyclics do not have a deleterious effect on left ventricular function even in patients with severe preexisting left ventricular impairment, but that patients with bundle-branch block are at increased risk to develop significant conduction complications when treated with a tricyclic. Further, patients with affective disorder may have a higher rate of mortality from cardiac disease compared with normal controls; recent data on heart rate variability abnormalities in depressed patients may be a first clue to the mechanism underlying that increased risk.