Sian Claire Owen, medical journalist for Cardio Debate, UK

Cocaine use has been shown to be associated with increased cardiovascular morbimortality. The American Heart Association famously dubbed the illegal drug as ‘The perfect heart attack drug’ after research showed it was associated with increased aortic stiffness, higher systolic blood pressure and increased thickness of the left ventricular wall. [1]

More recently, long-term cocaine use has been linked with increased rates of microvascular dysfunction. This is a serious issue because when cocaine users present in hospital emergency departments with chest pain, they tend to exhibit normal epicardial coronaries. Unless the underlying microvascular dysfunction is revealed, this could create a false sense of security in the patient, who may continue using the drug. [2]

An editorial published in the Journal of the American College of Cardiology by Varun Kumar, MD, Mount Sinai Hospital Medical Center, Chicago, US, describes how researchers assessed microvascular dysfunction in 202 cocaine users and 210 nonusers who underwent coronary angiography. The cocaine users were more likely to show symptoms of microvascular dysfunction than the nonusers. Cocaine users were also more likely to demonstrate faster flow in the right coronary artery, which is associated with ‘poorer clinical outcomes’. [3]

Cocaine use in the UK is not a growing problem as such, according to the Home Office the numbers of people who take the drug have fallen overall since 2008. However, the prevalence of the drug is still significant. A 2015/16 survey from the Home Office survey states that in adults aged 16 to 59 years cocaine is the second most widely used illegal drug after cannabis. [4] Furthermore, in the US cocaine is the illegal drug most often associated with hospital visits. [1]

Therefore, although the population is relatively small, it is important to be aware of underlying microvascular dysfunction in these patients. As Dr Kumar tells Healio.com: “This study will throw light on importance of assessing for coronary microvasculature and that normal epicardial coronaries is not the end of it. These cocaine patients with microvascular disease may need to be on antiplatelets in addition to stopping cocaine. Medical management with antiplatelets in these patients needs to be studied further.” [2]

References

  1. http://www.heart.org/HEARTORG/Conditions/More/MyHeartandStrokeNews/Illegal-Drugs-and-Heart-Disease_UCM_428537_Article.jsp#.Wo3pw6jFLIU
  2. https://www.healio.com/cardiac-vascular-intervention/percutaneous-coronary-intervention/news/online/%7Bf928a6a6-4268-4a2a-9e71-3153e4f503a9%7D/cocaine-use-confers-epicardial-microvascular-disease
  3. http://www.onlinejacc.org/content/71/8/954
  4. Drug Misuse: Findings from the 2015/16 Crime Survey for England and Wales.
Cardio Debate Expert Comments

Cocaine use is known to lead to serious cardiovascular events in a substantial proportion of individuals using this agent. As indicated in the CD cardionote, cardiac events, including acute myocardial infarction can develop develop in the absence of obstructive coronary artery disease and as a result of increased sympathetic activity associated with the use of cocaine. The deleterious effect of cocaine on the coronary microvessels has been documented in a recent study, which has also highlighted the importance of not ruling out cardiovascular disease solely based on the finding of angiographically normal coronary arteries. Epicardial coronary artery spasm is a well known mechanism whereby cocaine can lead to acute coronary syndrome, myocardial necrosis, ventricular arrhythmias and death in otherwise young and healthy individuals. Coronary microvascular dysfunction triggered by the administration of cocaine can also lead to severe myocardial ischaemia, as documented recently.

Physicians need to be aware of the frequent association among cocaine use, increased sympathetic activity, severe myocardial ischaemia and life threatening cardiac arrhythmias. The finding of a normal coronary arteriogram in individuals with symptoms and objective evidence of myocardial ischaemia should alert to the possibility of epicardial coronary artery spasm or severe coronary microvascular dysfunction.