Cocaine use associated with coronary microvascular dysfunction

CHICAGO — New data suggest that cocaine users with chest pain may have coronary microvascular dysfunction, despite the absence of significant epicardial CAD.

Varun Kumar, MD, an internist at Mount Sinai Hospital, Chicago, and colleagues conducted a blinded, retrospective study to assess coronary microvascular dysfunction in cocaine users as compared with nonusers.

Previous research has demonstrated that coronary microvascular dysfunction can impact morbidity and mortality, even in people with normal epicardial coronary arteries, according to the study background.

Varun Kumar

Using corrected TIMI frame count and TIMI perfusion grade, the researchers assessed microvascular dysfunction in 202 cocaine users and 210 randomly chosen nonusers who underwent coronary angiography from 2005 to 2013 at Mount Sinai Hospital in Chicago. The participants had no history of acute or recent MI, significant epicardial CAD or vasospasm.

Compared with nonusers, participants who used cocaine were more likely to have a TIMI perfusion grade of 0 or 1 for the left anterior descending artery (22% vs. 5%; P<.0001), circumflex artery (25% vs. 6%; P<.0001) and right coronary artery (42% vs. 8%; P<.0001), suggesting microvascular dysfunction, researchers reported at the American Heart Association Scientific Sessions.

Cocaine users had an elevated corrected TIMI frame count compared with nonusers for the left anterior descending artery (27.33 vs. 24.88; P=.03) and circumflex artery (41.11 vs. 38.23; P=.04), indicative of increased resistance in the microvasculature downstream, according to the researchers.

However, in the right coronary artery, more cocaine users than nonusers demonstrated faster flow; the corrected TIMI frame count was <14 (9% vs. 3%; P=.008). This has shown to be associated with poorer clinical outcomes, particularly in the context of impaired myocardial perfusion, according to the researchers.

“We need more research on this, but there’s some evidence to suggest cocaine itself can stimulate clot formation and may contribute to atherosclerosis and [CAD],” Kumar said in a press release. “The patient population may be small, but cocaine use is prevalent and we don’t want these patients to fall through the cracks.” – by Erik Swain

For more information:

Kumar V. Abstract #17488. Presented at: American Heart Association Scientific Sessions; Nov. 15-19, 2014; Chicago.

Disclosure: Kumar reports no relevant financial disclosures.