Impact of thrombus aspiration on myocardial tissue reperfusion and left ventricular functional recovery and remodeling after primary angioplasty.

BACKGROUND: 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.

METHODS AND RESULTS: 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).

CONCLUSIONS: Manual thrombus aspiration in the setting of primary PCI improves myocardial tissue-level perfusion as well as LV functional recovery and remodeling.