Role of aspiration and mechanical thrombectomy in patients with acute myocardial infarction undergoing primary angioplasty: an updated meta-analysis of randomized trials.

OBJECTIVES: This meta-analysis was designed to update data on clinical outcomes with aspiration thrombectomy or mechanical thrombectomy before primary percutaneous coronary intervention (PCI) compared with conventional primary PCI alone.

BACKGROUND: The clinical efficacy of thrombectomy in acute myocardial infarction (AMI) remains uncertain.

METHODS: Clinical trials that randomized AMI patients to aspiration (18 trials, n = 3,936) or mechanical thrombectomy (7 trials, n = 1,598) before PCI compared with conventional PCI alone were included.

RESULTS: The weighted mean duration of clinical follow-up was 6 months. Aspiration thrombectomy vs. conventional primary PCI (18 trials, n=3,936): Major adverse cardiac events (MACE) (risk ratio [RR]: 0.76; 95% confidence interval [CI]: 0.63 to 0.92; p = 0.006) and all-cause mortality (RR: 0.71; 95% CI: 0.51 to 0.99; p = 0.049) were significantly reduced with aspiration thrombectomy. Beneficial trends were noted for recurrent MI (p = 0.11) and target vessel revascularization (p = 0.06). Final infarct size (p = 0.64) and ejection fraction (p = 0.32) at 1 month were similar. ST-segment resolution (STR) at 60 min (RR: 1.31; 95% CI: 1.16 to 1.48; p < 0.0001) and Thrombolysis In Myocardial Infarction blush grade (TBG) 3 post-procedure (RR: 1.37; 95% CI: 1.19 to 1.59; p < 0.0001) were both improved with aspiration thrombectomy. Mechanical thrombectomy vs. conventional primary PCI (7 trials, n = 1,598): there was no difference between the mechanical thrombectomy and conventional primary PCI arms in the incidence of MACE (RR: 1.10; 95% CI: 0.59 to 2.05; p = 0.77), mortality (p = 0.57), recurrent MI (p = 0.32), target vessel revascularization (p = 0.19), or final infarct size (p = 0.47). A benefit in STR at 60 min (RR: 1.25; 95% CI: 1.06 to 1.47; p = 0.007), but not TBG 3 (RR: 1.09; 95% CI: 0.86 to 1.38; p = 0.48) was noted.

CONCLUSIONS: Thrombectomy during AMI by manual catheter aspiration, but not mechanically, is beneficial in reducing MACE, including mortality, at 6 to 12 months compared with conventional primary PCI alone.