Comparison of Manual Thrombus Aspiration With Rheolytic Thrombectomy in Acute Myocardial Infarction

Background Manual thrombus aspiration (MTA) is completely ineffective in 30% of cases, and the high profiles of the catheters prevent their use in tortuous and calcified vessels. The rheolytic thrombectomy (RT) device has the potential for improved thrombus removal in acute myocardial infarction as compared with MTA. No data exist on the comparison between the 2 techniques. Methods and Results Randomized study, including 80 acute myocardial infarction patients allocated to RT or MTA before infarct artery stenting. Primary end point of this study is residual thrombus burden by optical coherence tomography. Secondary end points are (1) residual thrombolysis in myocardial infarction thrombus grade; (2) postintervention thrombolysis in myocardial infarction flow and myocardial blush; (3) early ST-segment resolution; (4) percentage of malapposed stent struts at 6 months; (5) 6-month restenosis; and (6) 6-month major adverse cardiovascular events. All but 1 patient had residual thrombus after manual aspiration thrombectomy or RT. The number of optical coherence tomography quadrants containing thrombus in MTA arm was higher than in the RT arm, but this difference did not reach significance (median value 65 and 53, respectively; P=0.083). Large residual thrombus was more frequently revealed in the manual aspiration thrombectomy arm (patients with number of quadrants above the median value 60% in the manual aspiration thrombectomy arm and 37% in the RT arm, P=0.039). All markers of reperfusion were better in the RT arm. At 6 months, the percentage of malapposed stent struts in the MTA arm was higher than in the RT arm (2.7 +/- 4.5% and 0.8 +/- 1.6%, respectively; P=0.019). Conclusions MTA or RT allows only incomplete removal of thrombus in patients with acute myocardial infarction. The primary end point of the study was not met. However, RT as compared with MTA seems to be more effective in thrombus removal and myocardial reperfusion.