006: Impact of successful thrombus retrieval during primary percutaneous coronary intervention with thrombus aspiration on the infarct size and microvascular obstruction: Insight from contrast-enhanced mag

Abstract

hromboaspiration (TA) during primary percutaneous intervention (PPCI) is effective in opening the infarct-related artery in patients with ST-segment elevation myocardial infarction (STEMI), leading to better reperfusion and improved outcome. However, the effect of positive macroscopic efficiency of TA remains unknown. We aimed to evaluate the impact of positive thrombus retrieval during PPCI with manual TA on infarct size (IS) and microvascular obstruction (MVO) as assessed by contrast-enhanced magnetic resonance imaging (CE-MRI) in a subset of patients with STEMI. Inclusion criteria were patients aged <75years, with first STEMI referred for PPCI within 12 hours of onset of symptoms, infarct-related artery ≥2.5mm in diameter, thrombus score ≥3 and no prior history of coronary disease. All patients underwent TA before stenting and were categorized according to positive or negative TA. Clinical and procedural characteristics of study population were recorded and CE-MRI was performed at 5days and 6-months to evaluate MVO and IS. 88patients were enrolled, mean age 55±10years; 43.1% in the positive TA group. Main results are presented in the table. Clinical and procedural characteristics (90-min total ischemic time, ST-segment resolution, post-procedural TIMI flow grade and post-stenting myocardial blush grade, and peak troponin) did not differ significantly between groups. Independent predictors of final IS were: positive TA (OR 0.34, 95%CI 0.03-0.71), MVO (OR 1.75, 95%CI 1.28-0.71) and IS at 5days (OR 2.06, 95%CI 1.87-3.32). Positive thrombus retrieval during primary PPCI with manual TA in STEMI reduces MVO and in the acute phase and at 6 months and represents a powerful predictor of final infarct size. Table – Main results Negative TA (N=50) Positive TA (N+38) p MVO (%) 7.6±5.1 3.8±3.1 0.003 IS in the acute phase (%) 28.2±20.8 14.9±8.7 0.004 Final IS at 6 months (%) 22.3±19.3 12.0±8.3 0.002