Adjunctive manual thrombectomy improves myocardial perfusion and mortality in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction: a meta-analysis of randomized trials

The benefits of adjunctive mechanical devices to prevent distal embolization in patients with acute myocardial infarction (AMI) are still a matter of debate. Growing interests are on manual thrombectomy devices as compared with other mechanical devices. In fact, they are inexpensive and user-friendly devices, and thus represent an attractive strategy. The aim of the current study was to perform an updated meta-analysis of randomized trials conducted with adjunctive manual thrombectomy devices to prevent distal embolization in AMI. The literature was scanned by formal searches of electronic databases [MEDLINE, CENTRAL, EMBASE, and The Cochrane Central Register of Controlled trials (http://www.mrw.interscience.wiley.com/cochrane/Cochrane_clcentral_articles_ fs.html)] from January 1990 to May 2008, the scientific session abstracts (from January 1990 to May 2008) and oral presentation and/or expert slide presentations (from January 2002 to May 2008) [on transcatheter coronary therapeutics (TCT), AHA (American Heart Association), ESC (European Society of Cardiology), ACC (American College of Cardiology) and EuroPCR websites]. We examined all randomized trials on adjunctive mechanical devices to prevent distal embolization in AMI. The following keywords were used: randomized trial, myocardial infarction, reperfusion, primary angioplasty, rescue angioplasty, thrombectomy, thrombus aspiration, manual thrombectomy, Diver catheter, Pronto catheter, Export catheter, thrombus vacuum aspiration catheter. Information on study design, type of device, inclusion and exclusion criteria, number of patients, and clinical outcome was extracted by two investigators. Disagreements were resolved by consensus. A total of nine trials with 2417 patients were included [1209 patients (50.0%) in the manual thrombectomy device group and 1208 (50%) in the control group]. Adjunctive manual thrombectomy was associated with significantly improved postprocedural TIMI (thrombolysis in myocardial infarction) 3 flow (87.1 vs. 81.2%, P < 0.0001), and postprocedural MBG 3 (myocardial blush grade 3) (52.1 vs. 31.7%, P < 0.0001), less distal embolization (7.9 vs. 19.5%, P < 0.0001), and significant benefits in terms of 30-day mortality (1.7 vs. 3.1%, P = 0.04). This meta-analysis demonstrates that, among patients with AMI treated with percutaneous coronary intervention, the use of adjunctive manual thrombectomy devices is associated with better epicardial and myocardial perfusion, less distal embolization and significant reduction in 30-day mortality. Thus, adjunctive manual thrombectomy devices, if not anatomically contraindicated, should be routinely used among STEMI (ST-segment elevation myocardial infarction) patients undergoing primary angioplasty.