Use of thrombectomy devices in primary percutaneous coronary intervention: a systematic review and meta-analysis

AIMS: Primary percutaneous coronary intervention (PPCI) has become the treatment of choice in patients with ST-elevation myocardial infarction (STEMI) over the recent years. A number of studies have demonstrated a morbidity and mortality benefit over thrombolysis, which has been attributed to better coronary perfusion in patients undergoing PPCI. However although PPCI usually achieves normal flow in the affected epicardial vessel, myocardial reperfusion is not fully restored in a significant percentage of patients. This is commonly the result of distal thrombus embolization with subsequent impairment of myocardial microcirculation. Recognition of this has led to the development of a number of devices with different mechanisms of action that aim to reduce such distal embolization and therefore improve end myocardial perfusion. Recent studies indeed demonstrate that the use of such devices offer additional clinical advantage in patients undergoing PPCI compared to the current practice. This report focuses on thrombectomy devices and reviews the evidence that advocates their routine use in PPCI patients.

METHODS AND RESULTS: We have performed a systematic review of currently available thrombectomy devices. We also performed a literature search, using the terms "thrombectomy" and "thrombus aspiration" in PubMed and EMBASE. Thrombectomy devices were divided in "manual" and "non-manual" groups. We performed a meta-analysis of the available randomized control trials that compared adjunctive thrombectomy in PPCI to standard PPCI. The use of manual thrombectomy devices is associated with significant improvements in ST-segment resolution (STR) (p<0.00001), Myocardial Blush Grade (MBG) 3 (p<0.00001), Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow (p=0.01) as well as clinical parameters (43% reduction in mortality, p=0.04) in patients undergoing PPCI.

CONCLUSION: Current evidence advocates the routine use of manual thrombectomy devices in PPCI. Non-manual (mechanical) thrombectomy may have a role in selected PPCI patients with large caliber vessels and heavy thrombus burden although their routine use is not presently supported.