Relationship of left ventricular thrombus formation and adverse outcomes in acute anterior myocardial infarction in patients treated with primary percutaneous coronary intervention

Abstract

Background: The incidence of left ventricular thrombus (LVT) is 4% to 15% in patients with anterior acute ST-segment elevation myocardial infarction (ant-AMI) in the era of primary percutaneous coronary intervention (PPCI). And patients with LVT have higher in-hospital mortality.

Hypothesis: There is a relationship between LVT formation and 1-year major adverse cardio-cerebrovascular events (MACCE) in patients with ant-AMI treated by PPCI.

Methods: Our study population included 1488 consecutive patients with ant-AMI. The primary endpoint was the incidence of MACCE within 1 year after AMI. The secondary endpoint was the thrombosis disappearance.

Results: A total of 106 (7.1%) patients were diagnosed with LVT and 1382 (92.9%) patients without LVT. Patients with LVT had a higher incidence of MACCE than in patients without LVT (21.7%vs10.3%; P < 0.001). Univariate analysis showed LVT was associated with an increase in MACCE risk (odds ratio [OR] = 2.40; 95% confidence interval [CI] [1.37-4.21]; P < 0.001). When examining MACCE components individually, LVT was only associated with the incidence of congestive heart failure (OR = 2.41; 95% CI [1.29-4.58]; P = 0.001). After adjustment for principal confounders, LVT remained an independent risk factor for MACCE (HR = 2.28; 95% CI [1.12-6.38]; P = 0.020). Other independent predictors include 24-hour LVEF, creatine kinase peak value, and age. Further analysis found patients with LVT in international normalized ratio (INR) ≥ 2 group had lower MACCE risk and higher thrombus disappearance than in INR < 2 group (13.5%vs29.6%; P = 0.044; 90.4%vs74.1%; P = 0.029).

Conclusion: For patients with ant-AMI treated by PPCI, LVT is an independent predictor of 1-year MACCE events. Treatment with vitamin K antagonist in the therapeutic range (INR ≥ 2) has the potential to reduce MACCE risk and promote disappearance of thrombus.

Figure 1

Incidence of MACCE stratified according to LVT. Kaplan‐Meier analysis shows a statistically higher incidence of MACCE in patients with LVT (purple line) than those without LVT (green line) within 1 year follow‐up period (21.7% vs 10.3%). LVT, left ventricular thrombus; MACCE, major adverse cardio‐cerebrovascular events

Figure 2

Incidence of MACCE in patients with LVT stratified according to INR. The incidence of MACCE was significantly higher in patients with INR < 2 (purple line) than those with INR ≥ 2 (green line) within 1 year follow‐up period (29.6% vs 13.5%). INR, international normalized ratio; LVT, left ventricular thrombus; MACCE, major adverse cardio‐cerebrovascular events