Cardiovascular manifestations of tricyclic antidepressant overdose

• Published in: The American heart journal Vol. 100; no. 4; pp. 458 - 464
• Main Authors: Langou, Rene A., Van Dyke, Craig, Tahan, Steven R., Cohen, Lawrence S.
• Format: Journal Article
• Language: English
• Published: United States Mosby, Inc 01.10.1980
• Subjects: Adolescent; Adult; Aged; Amitriptyline - adverse effects; Amitriptyline - blood; Antidepressive Agents, Tricyclic; Blood Pressure - drug effects; Cardiac Output - drug effects; Cardiovascular System - drug effects; Electrocardiography; Female; Heart Rate - drug effects; Humans; Hypotension - chemically induced; Imipramine - adverse effects; Imipramine - blood; Male; Middle Aged; Tachycardia - chemically induced
• ISSN: 0002-8703; 1097-6744
• DOI: 10.1016/0002-8703(80)90657-2

The cardiotoxicity of tricyclic antidepressants (TCA) was studied in 35 patients admitted to Yale-New Haven Hospital for an acute overdose; 23 patients had amitriptyline overdose and 12 patients had imipramine overdose. Twenty-seven patients were female and eight were male. Their ages ranged from 13 to 73 years. Twenty patients were receiving TCA chronically, and none had prior cardiovascular disorders. Amitriptyline blood levels ranged from 180 to 1,560 ng./ml. and imipramine blood levels ranged from 150 to 1,732 ng./ml. Tachycardia occurred in 71% and systemic hypotension occurred in 51% of patients. The observed tachycardias were not corrected upon normalization of fluid and blood pressure derangements. Systemic hypotension was related to relative intravascular fluid depletion and peripheral vascular dilatation. Myocardial failure was not seen clinically or hemodynamically in studied patients. Electrophysiologic manifestations were those of conduction and repolarization abnormalities: prolonged PR interval in 11%, prolonged QRS complex in 29%, and prolonged QT c interval in 86% of the patients. No malignant ventricular arrhythmias were documented, and only 13 patients had ventricular premature beats, which were successfully suppressed with lidocaine infusions. All cardiovascular manifestations of TCA overdose disappeared when blood levels of TCA reached therapeutic range. Only supportive therapy was utilized in these 35 patients, and all patients recovered without complications.