Getting High: The Low-down for Cardiologists on Illicit Drugs and Marijuana

Cocaine is already on the radar of many heart specialists, but as marijuana use becomes legal in many states, much remains unknown.

Getting High: The Low-down for Cardiologists on Illicit Drugs and Marijuana

Rachel Bond, MD, was the cardiologist on call on a spring day in 2015 when a 38-year old man staggered into the busy New York City hospital emergency department (ED) complaining of “an elephant sitting on his chest.”

The man, Bond said, originally thought the problem was indigestion, so he had ignored the pain for the better part of an hour before deciding to walk to the hospital himself rather than call 9-1-1. By the time he was admitted, “they actually had taken him urgently to the back where they did an EKG,” she said. “And on the EKG he was found to have ST elevations throughout the precordial leads.”

The man was hypertensive and used tobacco but appeared to have little in the way of other risk factors and had no respiratory distress. His cardiac markers, however, were elevated. Pressed by physicians, the man came clean about another possible cause of his symptoms.

“He was an active cocaine user—he used it roughly about once every 2 weeks or so,” Bond told TCTMD. When the man’s chest pain did not subside with nitroglycerine he was given benzodiazepine and an intravenous calcium channel blocker, then sent for cardiac cath. The angiogram came back normal.

“Eventually, his symptoms resolved,” Bond, a staff cardiologist at Northwell Health in New York, NY, said.

Cocaine and Beyond

Knowing what effects illicit drugs can have on the cardiovascular system is essential in situations like this one, but according to Bond, cardiology training doesn’t specifically include a focus on recreational drug use or addiction. Instead, she says cardiologists need to fall back on any knowledge gleaned during their early general medicine and internal medicine training.

But the numbers suggest that cardiologists need to become more familiar with the signs and symptoms of cardiac manifestations of both prescription and illicit drug use.

Cocaine is a commonly used recreational, illegal drug. In 2014, there were approximately 1.5 million people over the age of 12 who had used cocaine within the past month, according to the most up to date data from the National Institute on Drug Abuse (NIDA). The NIDA website reports that in 2011 “cocaine was involved in 505,224 of the nearly 1.3 million visits to emergency departments for drug misuse or abuse,” with 40% of drug-related ED visits stemming from cocaine use.

In a review article published earlier this month in the Journal of the American College of Cardiology, Ofer Havakuk, MD (University of Southern California Keck School of Medicine, Los Angeles), and colleagues provide cardiologists with an overview on the numerous ways to deal with cocaine-induced cardiovascular events.

“Cocaine is the leading cause for drug-abuse-related visits to emergency departments, most of which are due to cardiovascular complaints,” they write. “Through its diverse pathophysiological mechanisms, cocaine exerts various adverse effects on the cardiovascular system, many times with grave results.”

But cocaine isn’t the only drug that should be on the radar of cardiovascular disease specialists. Opioids, for example, are known to cause bradycardia and vasodilation, and in combination with benzodiazepines they can lead to decreased cardiac function. Marijuana, perceived as a more “natural” product, also may also have cardiovascular implications that are poorly understood. This worries some experts, particularly as different jurisdictions legalize the use of the drug. Already marijuana is the most widely used recreational drug, with approximately 200 million users globally as of 2013, and while clinicians have known about its adverse effects for over 40 years, some concerns remain.

People think that marijuana is a safe drug to take, and unfortunately, it isn’t. Shereif H. Rezkalla

“People think that marijuana is a safe drug to take, and unfortunately, it isn’t,” cardiologist Shereif H. Rezkalla, MD (Marshfield Clinic, Marshfield, WI), who has studied drug cardiotoxicity use since the 1980s and co-authored the recent JACC paper, told TCTMD.

While marijuana’s cardiac effects are not as potent as cocaine’s, they are worth keeping in mind, particularly among users who have consumed large quantities of the drug, Rezkalla suggested. As of June 2017, 29 states and Washington, DC, have legalized medical marijuana, while eight states have legalized marijuana for recreational use.

Some experts believe these shifts present a substantial public health concern. Robert A. Kloner, MD (Huntington Medical Research Institutes, Pasadena, CA), told TCTMD: “Now that marijuana is legalized in many states for both recreational and medicinal use, we’re concerned that it could lead to issues for some patients.”

As marijuana gains wider acceptance across the country, there might be easier access to the drug. Kloner, another co-author on the JACC paper, noted that there are going to be “many more people using it,” which raises the points of whether it has any major cardiovascular effects and whether or not it is “safe for everyone.”

To TCTMD, Sheila Weix, MSN, RN (Marshfield Clinic), reported that marijuana “is in most urines that [I] see [in my work with prevention efforts]. There’s THC involved, so I think there needs to definitely be more research on this, particularly since it is one of the issues that you run into when you are looking at prevention efforts with drugs” Most people are not fully aware of the risks of the drug, which explains why marijuana is most widely used substance other than tobacco.

How Marijuana Affects the Heart

Experts have also drawn a temporal connection between marijuana use and the development of acute MI, cardiomyopathy, and sudden cardiac death. A 2013 review found that 38% of patients presented with symptoms within 24 hours of using cannabis. Moreover, a 2014 study found that marijuana use was associated with negative cardiovascular effects and sometimes even death among young and middle-aged adults.  The study assessed 1,979 patients and found that nearly 2% of them have marijuana-induced cardiovascular events.

A 2016 World Health Organization report says that “acute exposure to cannabis increases heart rate and blood pressure and can in some cases cause orthostatic hypotension.”

But not all research points in the same direction. As reported by TCTMD, an analysis of hospital records from eight US states, published in 2016, found that marijuana use is associated with lower short-term risks of death and shock among patients admitted for acute MI.

Education and open communication with patients is the only way physicians can stay ahead of the curve with illicit and recreational drugs.  Getting an honest history of a patient's drug use, however, can be challenging, Kloner admitted. “Patients may be fearful of revealing that they use drugs, or fearful or embarrassed of discussing it with others.” But getting the conversation started and encouraging patients to open up is an important aspect of educating them about the implications of drug use, he explained.

You would hate to think that your grandparents maybe using cocaine, but you’d be surprised occasionally. Richard Lange

Rezkalla agreed, adding that every physician, nurse, and journalist interested in medicine has a responsibility to engage in conversations on drug use and its negative consequences. “When people are aware of the dangers, . . . they will avoid it, they will make their kids avoid it,” he said.

Cocaine use extends across people of all ages, Richard Lange, MD (Texas Tech University Health Science Center, El Paso, TX), observed TCTMD. While most users are in their late 20s, he said, “deaths from cardiovascular complications have been reported in people in their 70s and 80s. You would hate to think that your grandparents maybe using cocaine, but you’d be surprised occasionally.”

New Power, New Problems

Back in early 2014, the American Heart Association flagged the lack of research into marijuana’s effects on the heart. What little research exists is out of date or observational. Kloner, for example, cited a 2001 report that found the odds of myocardial infarction increased by 4.8 times from baseline within the 60 minutes following the use of the drug.

Lange made the point to TCTMD that marijuana and cocaine are often used in combination with alcohol, tobacco, and other substances, making it difficult to determine their specific effects on the heart.

And then there is the impurity of the drugs themselves, an issue starkly illuminated by the fentanyl crisis sweeping North America and elsewhere, where the powerful and deadly opioid is being laced with other drugs. With marijuana, the issue is particularly problematic in states where the product has not been legalized.

Weix observed that in Wisconsin, where marijuana is grown illegally, “you really don't know what has been put into it or what it’s been exposed to.

That's the challenge with people who are using various substances, you will never quite know what you’ve had in any given substance. Sheila Weix

“That's the challenge with people who are using various substances, you will never quite know what you’ve had in any given substance,” she continued, likening it to popular television series that use forensic medicine techniques. “So when they come in presenting with a medical emergency, you’re doing CSI, you are trying to figure [this] out and they may not be forthcoming. People that are using may not want to tell you anything."

What’s Next

Going forward, Kloner believes more research needs to be done on what the drug does to coronary and cerebral blood flow as well as what it does to the heart muscle cells over time. “We need to know why, and how, so there are a lot of questions that remain,” he said.

As for Bond’s young patient, to the best of her knowledge his outcome was favorable. “His ST segments also resolved, and he was then monitored on a telemetry unit for another 24 hours just to make sure that there was no recurrence.” They also kept tabs on his cardiac enzymes and maintained the calcium channel blocker in case of further vasospasm. The patient was eventually discharged after receiving counseling on cocaine and tobacco and being given a recommendation to follow-up with a primary care physician.

Staying up to date with new guidelines is a way for physicians to remain aware of how to handle illicit drug use, Bond proposed. “For cardiologists in particular it is very easy because every few years the American College of Cardiology and the American Heart Association come up with these great guidelines for us on how to treat patients with acute coronary syndrome.” Within these, she said, there are usually explanations on how to approach symptoms related to use of illicit drugs like cocaine, and perhaps down the road, drugs that regulators have deemed safe for recreational use.


Ashley Lyles is the 2017 recipient of the Jason Kahn Fellowship in Medical Journalism. She is currently a graduate student…

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  • Bond, Kloner, Lange, Rezkalla, and Weix report no relevant conflicts of interest.