With increasing widespread marijuana legislation, use of the mind-altering substance has been on the rise among adults, according to a Columbia University study. Moreover, roughly 81 percent of the adults polled believe marijuana has at least one health benefit, according to a nationwide survey of 16,280 adults, published in the Annals of Internal Medicine, with pain management cited as the most common.
With cardiovascular disease the nation’s number one killer, however, it begs the question: Does marijuana help or harm the heart? All drugs carry risks and benefits. An editorial published in the Canadian Journal of Cardiologycontributes to the growing body of anecdotal evidence that marijuana may be harmful for patients with established cardiovascular disease.
The editorial recounts the case of a 70-year-old man with stable coronary artery disease who developed crushing chest pain and myocardial ischemia after consuming most of a marijuana lollipop, which was infused with 90 mg of delta-9-tetrahydrocannabinol (THC), the principle psychoactive constituent of cannabis. (In comparison, a single marijuana joint contains about 7 mg of THC.) The patient was taking the appropriate cardiac medication; he consumed the pot lollipop as a sleep aid and for pain relief.
The patient had smoked marijuana when he was younger but didn’t realize the THC potency of the lollipop. According to the authors, the patient’s cardiac event was likely triggered by an unexpected strain on his body from anxiety and fearful hallucinations that resulted from the unusually large amount of THC he ingested. The THC stimulated his sympathetic nervous system to increase cardiac output with tachycardia, hypertension and the release of the stress hormone, catecholamine.
Marijuana may be cardiotoxic a number of ways. If patients smoke it, they’re inhaling a combustible product. They may also experience acute anxiety, hallucinations and/or psychosis as a result of THC, which can result a surge catecholamines, which can have adverse acute cardiovascular effects.
With marijuana’s growing popularity among adults, the authors encourage healthcare providers to understand the potential adverse health risks of the drug, particularly on older patients with cardiovascular disease and the potential for marijuana toxicity with regard to use, dose, route of administration and degree of tolerance.
A solid place to start is a study in the Journal of Thoracic Disease, which provides an overview of the positive and negative effects of cannabis on the cardiovascular system. The upshot? The negatives, such as increased heart rate/blood pressure, ventricular tachycardia/ventricular fibrillation and an increased risk of acute coronary events, vasculitis, transient ischemic attacks, cerebrovascular stroke, reversible cerebral vasoconstriction syndrome and the development of stress cardiomyopathy outnumber the positives, such as lower prevalence of obesity and diabetes among marijuana users and that they’re less likely to smoke tobacco.
Although more research needs to be done to assess the public health risks of marijuana, it’s a good time to begin educating yourself and your patients about the adverse cardiovascular risks of marijuana use, including acute coronary events, stroke and possibly death.
Last updated on 9/25/19.