Abstract 17338: Effect of Intracoronary Thrombus Burden on Microvascular Dysfunction After Primary Percutaneous Coronary Intervention; a Prospective Trial Assessed With Index of Microcirculatory Resistance
INTRODUCTION: Aspiration thrombectomy (AT) has been advocated for ST-segment-elevation myocardial infarction (STEMI) and known to improve myocardial dysfunction after percutaneous coronary intervention (PCI), but it is not evaluated how a large thrombus affects post procedural results. We aimed to quantify the intracoronary thrombus in STEMI and to correlate it with post-procedural myocardial perfusion.
METHODS: In consecutive 73 STEMI patients who underwent primary PCI with aspiration thrombectomy, intracoronary thrombus burden was angiographically categorized as 2 groups; large thrombus burden (LTB), defined as ≥ 2 vessel diameter and small thrombus burden (STB). Main outcome measures were post-procedural TIMI flow, myocardial blush grade (MBG), and index of microcirculatory resistance (IMR) measured with a pressure sensor/thermistor-tipped guidewire.
RESULTS: History of hypertension, diabetes and smoking status were not difference between groups. Door to balloon time and left ventricular ejection fraction were similar between two groups. Patients with high thrombus burden had higher peak CK-MB and peak TroponinI and worse baseline TIMI flow grade. Post procedural TIMI flows and MBG were similar between groups. IMR was higher in patients with larger thrombus burden. In correlation analysis, large thrombus burden was positively correlated with peak CKMB, peak TnI and IMR (r=0.3, 0.4, and 0.34; p=0.006, <0.001, and 0.009; respectively). In multivariate analysis, LTB was an independent predictor of unfavorable IMR (>32mmHg·sec, OR: 1.1, 95% CI: 1.002-1.106, P = 0.04).
CONCLUSION: Large thrombus burden was associated with poor postprocedural microvascular dysfunction even after aspiration thrombectomy.
- © 2013 by American Heart Association, Inc.