Impact of Thrombus Aspiration on Myocardial Tissue Reperfusion and Left Ventricular Functional Recovery and Remodeling After Primary Angioplasty

Abstract

Failure to achieve myocardial reperfusion often occurs during percutaneous coronary intervention (PCI) in patients with myocardial infarction with ST-segment elevation. We hypothesized that manual thrombus aspiration during primary PCI would favorably influence tissue-level myocardial perfusion and left ventricular (LV) functional recovery and remodeling. We prospectively randomized 111 patients with ST-segment elevation myocardial infarction to either standard or thrombus-aspiration PCI. Primary end point of the study was postprocedural incidence of ST-segment resolution >or=70%. Secondary end points included Thrombolysis in Myocardial Infarction (TIMI) myocardial perfusion grade >or=2, the combination of TIMI myocardial perfusion grade >or=2 and ST-segment resolution >or=70%, post-PCI TIMI grade 3 flow, corrected TIMI frame count, myocardial contrast echocardiography score index, the absence of persistent ST-segment deviation, and time course of wall-motion score index, LV ejection fraction, and LV volume in the 2 groups. The incidence of ST-segment resolution >or=70% was 71% and 39% in the thrombus-aspiration and standard PCI groups, respectively (odds ratio, 3.7; 95% CI, 1.7 to 8.3; P=0.001). TIMI myocardial perfusion grade >or=2 was attained in 93% in the thrombus-aspiration group compared with 71% in the standard PCI group (P=0.006). The percentage of patients with ST-segment resolution >or=70% and TIMI myocardial perfusion grade >or=2 was significantly greater in the thrombus-aspiration group compared with the standard PCI group (69% versus 36%, P=0.0006). Myocardial contrast echocardiography score index was significantly higher in the thrombus-aspiration group compared with the standard PCI group (0.86+/-0.20 versus 0.65+/-0.31; P<0.0001). A significantly greater improvement in LV ejection fraction and in wall-motion score index from baseline to 6-month follow-up was observed in the thrombus-aspiration group compared with the standard PCI group (LV ejection fraction from 48+/-6% to 55+/-6% versus 48.7+/-7% to 49+/-8%, P<0.0001; wall-motion score index from 1.59+/-0.13 to 1.31+/-0.19 versus 1.64+/-0.20 to 1.51+/-0.26, P=0.008). Twelve patients (11%) developed LV remodeling at 6 months, 2 (4%) in the thrombus-aspiration group and 10 (18%) in the standard PCI group (P=0.02). Manual thrombus aspiration in the setting of primary PCI improves myocardial tissue-level perfusion as well as LV functional recovery and remodeling.