DEPRESSED-PATIENTS WITH CARDIOVASCULAR-DISEASE - TREATMENT CONSIDERATIONS

Tricyclic antidepressants (TCAs) act as antiarrhythmic drugs, with a p harmacology similar to quinidine and other class I antiarrhythmics. Th is characteristic has until recently been considered an advantage in p atients with both depression and arrhythmia. However, developments in cardiology make this situation appear more complicated. Class I antiar rhythmic drugs given to patients with ventricular arrhythmias followin g myocardial infarction increase rather than decrease mortality. The m echanism behind this increased mortality is not a function of the arrh ythmia, but rather of ischaemic heart disease. Because of the similari ty of TCAs to class I antiarrhythmic agents, TCAs may carry a similar risk. Recognition of this fact complicates the treatment of depression in patients with ischaemic heart disease. The selective serotonin (5- hydroxytryptamine; 5-HT) reuptake inhibitors (SSRI) have fewer effects on the cardiovascular system than TCAs. Therefore, these agents would appear to be a safer alternative to TCAs in patients with cardiovascu lar disease. However, their relative efficacy compared with the TCAs i s poorly established in the elderly, a patient group that often presen ts with cardiovascular disease. If a patient with ischaemic heart dise ase presents with mild to moderate depressive symptoms and a pharmacol ogical treatment for depression is indicated, we would begin with an S SRI. A TCA would only be considered if the patient failed to respond t o an adequate trial of the SSRI. In patients with severe, melancholic depression, but mild to moderate ischaemic heart disease, we prefer tr eatment with a TCA. In patients with severe, melancholic depression an d severe ischaemic disease, electroconvulsive therapy (ECT) is a safe alternative to drug treatment.