News Ticker

WIRE: Science session looks at marijuana use relation to heart and lung transplants

San Diego, California — Researchers presented information about the controversial issue of medical marijuana in relation to heart and lung transplantation at the 37th Annual International Society for Heart and Lung Transplantation (ISHLT) Meeting & Scientific Sessions, during Symposium 18: Weeding Out Fact from Fiction – the Highs and Lows of Marijuana Use in Transplant.

Specifically, presenters discussed potential impacts of legislation like California’s Assembly Bill 258, and additional issues concerning marijuana use in candidates for and recipients of heart or lung transplants.

The Medical Cannabis Organ Transplant Act passed in California in 2015 prohibits transplant centers from denying transplantation to medical marijuana users solely based on their use of marijuana. Currently, 23 states and the District of Columbia have passed some form of legislation legalizing the use of marijuana for medical or recreational use. During today’s discussion, researcher Lorriana Leard, MD, Associate Professor of Clinical Medicine at the University of California San Francisco delved into the implication of how doctors think about candidates given the legal considerations in some states.

“The topic of cannabis use within the field of heart and lung transplantation has many unanswered questions,” said ISHLT 37th Annual Meeting and Scientific Sessions Program Chair and Board Member Jeffrey Teuteberg, MD. “There is little data on how the drug impacts patients either before or after heart and lung transplant”

University of Toronto Department of Medicine Associate Professor, Lianne Singer, MD shared that there is currently a ‘major’ knowledge gap about how cannabis affects transplanted hearts and lungs.  She noted that smoking cannabis is associated with some pulmonary and cardiac risks, but it is currently unknown whether transplant recipients are more vulnerable. Infections can be transmitted through contaminated marijuana or smoking with infected individuals, which can have serious consequences for post-transplant patients. Lastly, she discussed that cannabis has interesting effects on the immune system and posed the question – can it prevent/treat organ rejection.

ISHLT Heart Transplant Guidelines

Section 5.0 of the 2016 ISHLT Listing Criteria for Heart Transplantation, a guideline document created by ISHLT and its members, identifies that the use of medical and legalized marijuana still has many unknowns. The guidelines reference studies that showed concerns of “heightened predisposition to fungal infections” in organ transplantation, in patients using marijuana.

Further, the guidelines advise caution for transplant centers in listing candidates, unable to give up use of cannabis, or use it heavily, as it impairs cognitive function, which could lead to medication confusion post-transplant. At this time, the guideline recommends each center develop their own specific criteria for deciding candidacy for marijuana users.


The International Society for Heart and Lung Transplantation (ISHLT) is a not-for-profit professional organization with more than 2,700 members from over 45 countries dedicated to improving the care of patients with advanced heart or lung disease through transplantation, mechanical support and innovative therapies via research, education and advocacy. For more information, visit

Leave a comment