Marijuana and Cardiac Arrhythmias: A Scoping Study.

With increasing legalization, marijuana has become the most commonly abused substance in the United States. Together with the introduction of more potent marijuana products over the years, more adverse events are being reported and clinically characterized. Delta-9-tetrahydrocannabinol (THC) is the active psychotropic component of marijuana, which acts mainly on G-protein cannabinoid receptors CB1 and CB2. Multiple isolated cases of arrhythmias associated with marijuana use have been published. In this manuscript we conduct a scoping study of a total of 27 cases of arrhythmia associated with marijuana. Most cases were reported in young males (81%) with a mean age of 28 ± 10.6 years. Atrial fibrillation (26%) and ventricular fibrillation (22%) were the most common arrhythmias reported. Brugada pattern was reported in 19% of the patients. Marijuana associated arrhythmia resulted in a high mortality rate of 11 %. While the exact mechanisms of arrhythmias associated with marijuana are not clear, several hypothesis have been introduced including the effect of marijuana on cardiac ion channels as well as its effects on the central nervous system. In this paper we discuss the possible mechanisms of marijuana induced arrhythmia citing the evidence available to-date.