A Prospective Randomized Trial of Thrombectomy Versus No Thrombectomy in Patients With ST-Segment Elevation Myocardial Infarction and Thrombus-Rich Lesions : MUSTELA (MUltidevice Thrombectomy in Acute ST-Segment ELevation Acute Myocardial Infarction) Tria

ObjectivesThe aim of this study was to evaluate whether thrombectomy during primary percutaneous coronary intervention (pPCI) in patients with high thrombus burden improves myocardial reperfusion and reduces infarct size.BackgroundThrombectomy aims at reducing distal thrombotic embolization during pPCI, improving myocardial reperfusion and clinical outcome.MethodsWe randomized 208 patients with high thrombus burden in a 1:1 ratio to either pPCI with thrombectomy (Group T) or standard pPCI (Group S). Thrombectomy was performed with either rheolytic or manual aspiration catheters. Three-month magnetic resonance imaging was performed to assess infarct size and transmurality and microvascular obstruction (MVO). The primary endpoints were ST-segment elevation resolution (STR) >70% at 60 min and 3-month infarct size.ResultsThe baseline profile was similar between groups, except for a higher rate of initial Thrombolysis In Myocardial Infarction flow grade 3 in Group S (p = 0.002). Group T showed a significantly higher rate of STR (57.4% vs. 37.3%; p = 0.004) and of final myocardial blush 3 (68.3% vs. 52.9%; p = 0.03). Group T and Group S did not differ with regard to infarct size (20.4 ± 10.5% vs. 19.3 ± 10.6%; p = 0.54) and transmurality (11.9 ± 12.0% vs. 11.6 ± 12.7%; p = 0.92), but Group T showed significantly less MVO (11.4% vs. 26.7%; p = 0.02) and a higher prevalence of inhomogeneous scar (p < 0.0001). One-year freedom from major adverse cardiac events was similar between groups.ConclusionsThrombectomy as an adjunct to pPCI in patients with high thrombus load yielded better post-procedural STR and reduced MVO at 3 months but was not associated with a reduction in infarct size and transmurality. Thromboaspiration in Patients With High Thrombotic Burden Undergoing Primary Percutaneous (Coronary Intervention; NCT01472718)