Cocaine Abuse: Repolarization Abnormalities and Ventricular Arrhythmias

Gamouras, George A. MD
Monir, George MD
Plunkitt, Kenneth MD
Gursoy, Sinan MD
Dreifus, Leonard S. MD

From the Department of Medicine, Division of Cardiovascular Diseases, University of South Florida, Tampa, Florida.

Submitted September 21, 1999; accepted in revised form December 17, 1999.

Correspondence: Leonard S. Dreifus, M.D., 739 Cricklewood Terrace, Heathrow, FL 32746 (E-mail: [email protected]).

American Journal of the Medical Sciences 320(1):p 9-12, July 2000.

Increased QT and QT dispersion has been linked to arrhythmic death in patients with congenital and acquired long QT syndromes. The repolarization abnormalities were studied in 45 patients with a history of chest pain, somnolence, or disorientation admitted to the hospital for cocaine abuse. Group I was composed of patients with anginal chest pain (n = 23), whereas in group II patients (n = 22), chest pain was absent. Measurements were made of QT and QTc and of QT and QTc dispersion characteristics. Cocaine prolonged the QT, QTc, and QTc dispersion and enhanced the appearance of abnormal U waves. Lethal ventricular arrhythmias were observed in 3 patients. Anginal chest pain may be a marker for myocardial ischemia and, in the presence of abnormal ventricular repolarization, may cause lethal ventricular arrhythmias and sudden death in persons exposed to cocaine.