Systematic review of 62 cases links marijuana use to heart attacks in young people with no risk factors

Across 46 published studies describing 62 patients who had acute myocardial infarction following marijuana use, the mean age was 27.7 years with male predominance. Average onset was within 5 hours of use. Angiographic findings were normal in 36.8%, while the left anterior descending artery was the most commonly occluded vessel (42.1%). Seven deaths were reported among the 62 cases.

Systematic review of case reports, case series, and letters to the editor from MEDLINE describing individuals with acute myocardial infarction associated with marijuana use. 46 studies with 62 total patients included.

Heart attacks in people under 30 with no traditional risk factors are rare. The pattern of young, otherwise healthy users having coronary events shortly after marijuana use suggests a direct pharmacological trigger worth understanding.

With an average of 3.7g consumed over nearly 10 years, these were not one-time users. The 37% with completely normal coronary arteries suggests marijuana may cause coronary vasospasm rather than atherosclerosis, an important mechanistic distinction.

Case reports only (lowest level of evidence); publication bias toward unusual presentations; cannot establish causation from case series; no denominator to calculate actual risk; other substance co-use may be underreported.