Strategies for Thrombus Clearance in Patients With ST-Segment Elevation Myocardial Infarction

Thrombus burden in patients with ST-segment elevation myocardial infarction (STEMI) facilitates distal embolization and microvascular obstruction (MVO), jeopardizing tissue reperfusion despite an open epicardial artery. Early single-center randomized trials (Thrombus Aspiration during Percutaneous Coronary Intervention in Acute Myocardial Infarction Study (TAPAS), Thrombectomy With Export Catheter in Infarct-Related Artery During Primary Percutaneous Coronary Intervention (EXPIRA)) have exhibited improved microvascular surrogates and suggested clinical benefit; however, pragmatic multicenter trials did not confirm efficacy for a routine aspiration strategy, i.e., Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia (TASTE) and Trial of Routine Aspiration Thrombectomy with PCI versus PCI Alone in Patients with STEMI (TOTAL) did not demonstrate a reduction in death, reinfarction, or heart failure with aspiration plus percutaneous coronary intervention (PCI) versus PCI alone. In TOTAL, routine aspiration intake increased stroke: 0.7% versus 0.3% at 30 days (hazard ratio (HR) 2.06; 95% confidence interval (CI) 1.13–3.75), while the excess was evident within 48 hours and the signal was sustained to 180 days (1.0% versus 0.5%, HR 2.00, 95% CI 1.25–3.20); meanwhile, disabling or fatal strokes were also more frequent (HR 2.69). Accordingly, the current European Society of Cardiology (ESC) 2023 and American College of Cardiology/American Heart Association (ACC/AHA) 2025 guidelines dissuade routine manual aspiration (Class III, Level A) while supporting selective bailout application when large residual thrombus or refractory no-reflow exists despite standard measures. Device-based alternatives (rheolytic thrombectomy, distal protection) have failed to improve hard outcomes in native vessel primary PCI; meanwhile, newer continuous aspiration and coronary stent-retriever systems remain practical but unproven in outcomes trials. This narrative review appraises randomized and mechanistic evidence and proposes a practical, safety-first algorithm. This approach includes performing primary PCI rapidly with guideline-directed antithrombotic therapy; considering thrombectomy only in rare cases of very large thrombus burden when it is likely to improve flow; if aspiration is utilized, careful purging must be ensured to prevent air embolism, continuous negative pressure must be maintained, and a single slow pass performed with sustained suction to minimize embolization. Currently, in practice, the evidence overwhelmingly argues against routine aspiration. However, a selective and technically disciplined bailout approach may still be warranted in carefully chosen patients.