Prognostic Impact of Residual Thrombus After Aspiration Thrombectomy in ST-Elevation Myocardial Infarction.

BACKGROUND

The prognostic significance of residual thrombus volume after aspiration thrombectomy in patients with ST-segment elevation myocardial infarction (STEMI) remains unclear.

OBJECTIVES

The authors aimed to investigate whether residual thrombus volume quantified by post-aspiration optical coherence tomography (OCT) is associated with major adverse cardiovascular events (MACE) in patients with STEMI undergoing primary percutaneous coronary intervention (PCI).

METHODS

This retrospective single-center study included 233 patients with STEMI who underwent manual aspiration thrombectomy followed by OCT-guided primary PCI within 12 hours of symptom onset. Residual thrombus volume was quantified at 1.0-mm intervals. The optimal cutoff was determined using maximally selected log-rank statistics. The primary endpoint was MACE, defined as cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Associations with MACE were evaluated using Kaplan-Meier and Cox regression analyses.

RESULTS

During a median follow-up of 2.5 years (IQR: 1.3-3.5 years), MACE occurred in 46 patients (19.7%). Patients with residual thrombus volume ≥4.14 mm3 had a higher cumulative incidence of MACE than those with <4.14 mm3 (log-rank P = 0.0018). Residual thrombus volume remained independently associated with MACE as a continuous variable (adjusted HR: 1.014 per 1 mm3 increase; 95% CI: 1.001-1.027; P = 0.031). Similar findings were observed using the 4.14-mm3 cutoff (adjusted HR: 2.95; 95% CI: 1.51-5.74; P = 0.002).

CONCLUSIONS

Residual thrombus burden quantified by OCT after aspiration thrombectomy was independently associated with adverse cardiovascular outcomes in patients with STEMI. Quantitative OCT assessment may provide complementary prognostic information for post-PCI risk stratification.