Aspiration thrombectomy in ST-segment elevation myocardial infarction is recommended by current guidelines based on several randomized trials. There are no trials assessing thrombectomy in non-ST-segment elevation myocardial infarction (NSTEMI) patients.The TATORT-NSTEMI (Thrombus Aspiration in Thrombus Containing Culprit Lesions in Non-ST-Elevation Myocardial Infarction) trial sought to assess the effect of aspiration thrombectomy on microvascular injury in patients with NSTEMI compared with standard percutaneous coronary intervention (PCI).This prospective, controlled, multicenter study randomized 440 patients to adjunctive thrombectomy (n = 221) compared with conventional PCI (n = 219) in NSTEMI patients with thrombus-containing lesions. The primary endpoint of the extent of microvascular obstruction (MO) in the percentage of left ventricular mass (%LV) was assessed by cardiac magnetic resonance imaging within 4 days. Secondary endpoints included infarct size, myocardial salvage index, and angiographic parameters including myocardial blush grade and Thrombolysis In Myocardial Infarction flow grade. The combined clinical endpoint consisted of death, reinfarction, target vessel revascularization, and new congestive heart failure within 6 months.The primary endpoint of MO was not different between the thrombectomy and the standard PCI group with 2.0%LV (interquartile range [IQR]: 0.8 to 4.1) versus 1.4%LV (IQR: 0.7 to 2.6) (p = 0.17). Similarly, no significant differences were observed for infarct size (8.6%LV; IQR: 4.0 to 14.7 vs. 7.4%LV; IQR: 4.1 to 13.1; p = 0.46), myocardial salvage index (63.3; IQR: 35.4 to 87.2 vs. 65.6; IQR: 46.9 to 82.6; p = 0.45), or angiographic parameters such as blush grade (p = 0.63) and Thrombolysis In Myocardial Infarction flow grade (p = 0.66). Clinical follow-up at 6 months revealed no differences in the combined clinical endpoints (p = 0.22).Aspiration thrombectomy in conjunction with PCI in NSTEMI with a thrombus-containing lesion does not lead to a reduction in MO. (Thrombus Aspiration in Thrombus Containing Culprit Lesions in Non-ST-Elevation Myocardial Infarction [TATORT-NSTEMI]; NCT01612312).