Cannabis use linked to higher heart attack risk during surgery

A study presented at the ANESTHESIOLOGY®2026 annual meeting indicates that cannabis use is associated with a 46% increased risk of myocardial infarction, or heart attack, during or shortly after surgery compared to non-users. The research, led by Nader D. Nader of the University at Buffalo, analyzed data from five studies involving 44,312 surgical patients.

In a contrasting finding, researchers observed that cannabis users had a 22% lower risk of venous thromboembolism, which refers to blood clots in the veins. However, the authors noted that this does not establish a protective effect and requires further investigation to understand how cannabis influences inflammation and clotting.

The study found no significant links between cannabis use and death, stroke, respiratory failure, or acute kidney injury. Medical professionals emphasize the importance of patients disclosing marijuana use—whether medical or recreational—to anesthesiologists to allow for necessary safety precautions during and after procedures.