People who used cannabis had a 46% higher risk of a heart attack during or shortly after surgery than people who did not, according to a review of five studies covering 44,312 surgical patients presented at the ANESTHESIOLOGY 2026 annual meeting in San Diego. The American Society of Anesthesiologists (ASA) released the findings Oct. 18.
The research shows an association, not proof that cannabis caused the heart attacks. It was presented as meeting research, and the release does not report confidence intervals or explain how fully the studies accounted for other risk factors such as tobacco use, age, diabetes or existing heart disease.
