Impact of thrombus aspiration on left ventricular remodeling and function in patients with ST-segment elevation myocardial infarction: A meta-analysis of randomized controlled trials.

BACKGROUND: Routine thrombus aspiration (TA) does not improve clinical outcomes in patients with ST-segment-elevation myocardial infarction (STEMI), although data from meta-analyses suggest that patients with high thrombus burden may benefit from it. The impact of TA on left ventricular (LV) functional recovery and remodeling after STEMI remains controversial. We aimed to pool data from randomized controlled trials (RCTs) on the impact of TA on LV function and remodeling after primary percutaneous coronary intervention (pPCI). METHODS: PubMed and CENTRAL databases were scanned for eligible studies. Primary outcome measures were: LV ejection fraction (LVEF), LV end diastolic volume (LVEDV), LV end systolic volume (LVESV) and wall motion score index (WMSI). A primary pre-specified subgroup analysis was performed comparing manual TA with mechanical TA. RESULTS: A total of 28 studies enrolling 4990 patients were included. WMSI was lower in TA group than in control (mean difference [MD] -0.11, 95% confidence interval [CI] -0.19 to -0.03). A greater LVEF (MD 1.91, 95% CI 0.76 to 3) and a smaller LVESV (MD -6.19, 95% CI -8.7 to -3.6) were observed in manual TA group compared to control. Meta regressions including patients with left anterior descending artery (LAD) involvement showed an association between TA use and the reduction of both LVEDV and LVESV (z = -2.13, p = 0.03; z = -3.7, p < 0.01) and the improvement in myocardial salvage index (z = 2.04, p = 0.04). CONCLUSION: TA is associated with improved LV function. TA technique, total ischemic time and LAD involvement appears to influence TA benefit on post-infarction LV remodeling.