Marijuana and the Heart

Public opinion of marijuana has improved greatly with more then half of states now having the drug legalized in some fashion. This sudden swing in favorability is matched by the growing erroneous belief of the public that marijuana is relatively benign, especially compared to currently legal substances. This is effective yet extremely flawed logic that greatly hinders the spreading of actual scientific evidence on the dangers of pot. One such dangers is the increased risk of heart attack. We have curated some stories and studies on this danger which you can find below.

Marijuana abuse was independently associated with an eye-opening doubled risk of acute MI in a large, retrospective, age-matched cohort study, Ahmad Tarek Chami, MD, reported at the annual meeting of the American College of Cardiology.

"I hit the ground, and I felt something inside my heart," he recalled. "It wasn't, like, a muscular injury. It was something internal. ... I just laid down and said, 'I'm done for the week.'"

Minutes later in the interview, he said, "The moment I laid down at the back of [that gym], I instantly knew it was because of that medical marijuana."

A new study from Boston's Beth Israel Deaconess Medical Center and Harvard Medical School says marijuana increases the risk of having a heart attack within the first hour of smoking to five times that of non-smokers.

A study released suggests that marijuana use can weaken heart muscles, particularly in young men. The study was presented at the annual scientific conference of the American Heart Association in New Orleans.

Younger marijuana users were twice as likely as non-users to experience stress cardiomyopathy, a sudden, usually temporary, weakening of the heart muscle that occurs more commonly in older women.

Addition Information

  • Heart disease, diabetes, all forms of auto-immune disease (a growing problem), addiction and obesity are connected to high ACE scores (Kaiser ACE Study).  
  • Marijuana has short and long-term effects, especially on the cardiopulmonary system.  Marijuana raises the heart rate by 20-100 percent shortly after smoking; this effect can last up to three hours. It was estimated that marijuana users had a 4.8-fold increase in the risk of heart attack in the first hour after smoking the drug. Elevated risk may be due to increased heart rate as well as the effects of marijuana on heart rhythms, causing palpitations and arrhythmias. Risk may be greater in older individuals or in those with cardiac vulnerabilities. Marijuana use found to increase blood pressure and heart rate and decrease the oxygen-carrying capacity of the blood. (Mittleman MA, Lewis RA, Maclure M. Triggering myocardial infarction by marijuana. Circ. 2001;103(23): 2805-9.)
  • Marijuana elevates the risk of heart attack 4 times 1 hour after smoking. (The Health Effects of Marijuana., Sept 30, 2002)
  • Marijuana use raises heart rate for up to three hours, which can increase the chance of a heart attack or dangerous cardiac event.
  • Little public awareness of the potentially hazardous cardiovascular effects of cannabis, e.g. marked increase in heart rate or supine blood pressure. (Case study of two putative healthy men who died unexpectedly under the acute influence of cannabinoids (Sudden unexpected death under acute influence of cannabis by B. Hartung, S. Kauferstein, S. Ritz-Timme, T. Daldrup; Jan 2014)
  • There is evidence that marijuana use and secondhand exposure pose health risks, including increased risk for cancer, heart attack, stroke, reproductive toxicity, respiratory impairment, long-lasting detrimental changes in brain function, and increased risk for addiction. (UCSF ANALYSIS OF PROPOSED [MARIJUANA] INITIATIVES – TOBACCO CONTROL AND MARIJUANA – Analysis)
  • Rat blood vessels took at least three times longer to recover function after only a minute of breathing secondhand marijuana smoke, compared to recovery after a minute of breathing secondhand tobacco smoke. When rats inhaled secondhand marijuana smoke for one minute, their arteries carried blood less efficiently for at least 90 minutes, whereas similar exposure to secondhand tobacco smoke caused blood vessel impairment that recovered within 30 minutes.(Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.)
  • Evidence linking marijuana and risk of stroke grows… marijuana use may increase heart complications in young, middle-aged adults. 
  • Cannabis causes blood shot eyes, accelerated heart rate (tachycardia), muscle tremors, forgetfulness, and many other effects. (The Drug Recognition Expert (DRE) Response to the Drug Impaired Driver: An Overview of the DRE Program, Officer, and Procedures)