Abstract 17488: Effect of Cocaine on Coronary Microvasculature

Background: Presence of coronary microvascular dysfunction despite normal epicardial coronary arteries is known to significantly impact mortality and morbidity. With the increasing number of cocaine users among urban population, it is imperative to assess its effect on the coronary microvasculature. Method: In this blinded, retrospective study, microvascular dysfunction was assessed using corrected Thrombolysis In Myocardial Infarction (TIMI) frame count (cTFC) and TIMI perfusion grade (TMPG), in an available consecutive series of 202 cocaine users in the absence of acute or recent MI, significant epicardial coronary artery disease (CAD) or vasospasm, among the 775 cocaine users who underwent coronary angiography at Mount Sinai Hospital, Chicago from 2005 to 2013. Applying the same criteria, the cTFCs and TMPGs were then compared with 210 randomly chosen non-cocaine users. Angiographers were blinded when determining the cTFC and TMPG. Results: The TMPG 0/1 for the left anterior descending (LAD), circumflex (LCx), and right coronary (RCA) arteries were statistically significant among cocaine users (LAD 22% versus 5%, p=<0.0001; LCx 25% versus 6%, p=<0.0001; RCA 42% versus 8%, p=<0.0001). For the cTFC, the LAD and LCx were significantly elevated among cocaine users (27.33 ± 10.9 versus 24.88 ± 10.05, p=0.03 and 41.11 ± 14.28 versus 38.23 ± 12.69, p=0.04; respectively). Additionally, there was a significant percentage of cocaine users with cTFC<14 (i.e. faster flow) observed in the RCA (9% versus 3%; p=0.008). Conclusion: Our study concludes that there is significant coronary microvascular dysfunction associated with cocaine use despite the absence of significant epicardial CAD. Additionally, reduced coronary filling time might be the reason for the observed higher frequency of hyperemic flow in the RCA among cocaine users, which is associated with poorer clinical outcomes, particularly in the context of impaired myocardial perfusion.