Independent Risk Factors of Non-Resolution Mural Thrombus in ST-Segment Elevation Myocardial Infarction Patients with Left Ventricular Aneurysms.

BACKGROUND

The clinical prognosis of ST-elevation myocardial infarction (STEMI) patients with mural thrombus in left ventricular aneurysm (MTLVA) remains poor; moreover, the risk factors associated with the non-resolution (persistent or recurrent) of MTLVA are not well understood. This study aimed to identify independent risk factors for MTLVA non-resolution.

METHODS

A total of 133 STEMI patients (mean age 62 ± 11 years, 80.5% male) with MTLVA, admitted to our department between 2014 and 2022, were included in this retrospective analysis. Patients were categorized into two groups: resolution (n = 59) and non-resolution [persistent (n = 72) or recurrent (n = 2) MTLVA; n = 74]. The median follow-up duration was 25 months, during which adverse events were monitored, including stroke, re-revascularization, major bleeding, systemic embolism, and cardiac death.

RESULTS

The prevalence of non-resolution was 55.6%. Non-resolution was significantly associated with elevated lipoprotein (a) [Lp(a)] levels (>270 mg/L, hazard ratios (HR) 2.270, = 0.003), larger left ventricular aneurysm (LVA) area (>4.5 cm, HR 4.038, < 0.001), and greater mural thrombus (MT) area (>2.2 cm, HR 2.40, = 0.002), independent of other risk factors, such as hypercholesterolemia and left circumflex artery (LCX)-related STEMI. Baseline left ventricular ejection fraction (LVEF) was lower in the non-resolution group (41.7% vs. 45.7%, = 0.008). During follow-up, the LVEF remained lower in the non-resolution group and increased in the resolution group. The composite of adverse events was significantly higher in the non-resolution group (28.4% vs. 8.5%, = 0.003), including stroke ( = 0.025) and systemic embolism ( = 0.034).

CONCLUSIONS

Independent risk factors for thrombus non-resolution in STEMI patients with MTLVA include elevated Lp(a), larger LVA and MT areas. These factors contribute to thrombus persistence and are associated with worse clinical outcomes. However, further studies are needed to assess targeted management strategies for high-risk patients.