Cardiac magnetic resonance in cocaine-induced myocardial damage: cocaine, heart, and magnetic resonance.

The use of cocaine constitutes a major health problem. Cocaine use is associated with acute and chronic complications that might involve any system, the most common being the cardiovascular system. The precise incidence of cocaine-induced cardiomyopathy remains mysterious and probably underreported. Cocaine use should be considered in young patients presenting with chest pain or heart failure without other underlying risk factors. Cocaine-related cardiovascular complications can be acute or chronic and include ischemic and non-ischemic events. Frequent cocaine users have a seven-fold higher risk of myocardial infarction. In addition to its ischemic effects, other cardiovascular complications of cocaine use and abuse are hypertensive crises, aortic dissection or aortic rupture, cerebral hemorrhage, arrhythmias and sudden cardiac death, myocarditis, dilated cardiomyopathy, heart failure, and endocarditis. The mechanism of cocaine's cardiovascular toxicity relates to its sympathomimetic effect, to the block of voltage-dependent K+ and Na2+ channels, and a hypersensitivity reaction to drug or contaminants, such as amphetamine, sugars, or talc. Cardiac magnetic resonance (CMR) can provide a valuable assessment of cocaine-induced myocardial damage both in acute and chronic cardiac complications: it gives prognostic information in clinically relevant settings, and it identifies silent myocardial damage in asymptomatic patients. Indeed, CMR study should be considered in symptomatic cocaine users to assess the extent and evolution of myocardial injury. Furthermore, it was suggested to repeat CMR after 4-8 months of appropriate management to evaluate myocardial response to abstinence and medical therapy.