BACKGROUND: Marijuana is a commonly abused illicit drug in the United States (US). Regular marijuana usage has been linked to many adverse cardiovascular effects. Our case describes the association of abusing marijuana and the development of sick sinus syndrome.

CASE REPORT: A 27-year-old male carpenter was admitted to the hospital for recurrent syncopal episodes. He reported 2 episodes of syncope every month for the last 5 years. He denied alcohol or nicotine intake but reports using marijuana daily. He also reported cervical injuries due to syncope in the past. Physical examination was unremarkable. Orthostatic vitals were negative. Electrocardiogram (ECG) showed sinus bradycardia. A series of investigations, including a stress test and tilt table testing, were negative. The drug screen was positive for marijuana. A loop recorder was implanted to evaluate the cause of syncope and was positive for a long sinus pause of more than 3 second, indicative of sick sinus syndrome. The patient was successfully treated with a permanent pacemaker with no further events on follow-up after 6 months.

CONCLUSIONS: The case we report here adds to the literature that several reversible etiologies are shown to be associated with the development of sick sinus syndrome, in which marijuana abuse can be one of them. We strongly suspect that marijuana was the cause of this patient’s sick sinus syndrome after ruling out all the possible etiologies. The relation between marijuana use and sick sinus syndrome needs to be further investigated in the future.  

Keywords: Bradycardia, Marijuana Abuse, sick sinus syndrome, Syncope