Abstract 15386: Incidence, Predictors and Prognostic Significance of Left Ventricular Thrombi in Patients With Acute Reperfused St-Elevation Myocardial Infarction - Insights From Cardiac Magnetic Resonance
Background: Data on the exact incidence and predictors of left ventricular (LV) thrombus formation after primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) are scarce. Moreover, data on the prognostic significance of LV thrombi on hard clinical outcome measures are completely lacking.
Non-invasive investigation by gadolinium-enhanced cardiac magnetic resonance imaging (CMR) enables the detection of LV thrombi with high spatial resolution and superior diagnostic accuracy as compared to echocardiography. Aim of our study was 1) to assess the incidence, determinants and clinical characteristics of LV thrombi in a large multicenter cohort of high-risk STEMI patients, 2) to assess the prognostic significance of LV thrombi at one-year follow-up.
Methods: We enrolled 780 STEMI patients reperfused by primary angioplasty (<12 h after symptom onset) in this CMR study at 8 centers. CMR was completed within one week after infarction using a standardized protocol. Central core lab-masked analyses for the presence of LV thrombi were performed. The primary clinical endpoint of the study was the occurrence of major adverse cardiac events (MACE) at one year follow-up.
Results: LV thrombi were detected in 32 patients (4.1%). The presence of LV thrombi was associated with larger infarcts (p<0.001), less myocardial salvage (p<0.001), impaired LV ejection fraction (p=0.02) and more pronounced reperfusion injury (late microvascular obstruction p=0.004, intramyocardial hemorrhage p=0.02). In multivariable regression analysis infarct size, anterior infarction, age and pain-to-balloon time emerged as significant predictors of LV thrombi. Patients with LV thrombi had a significantly higher MACE rate at 12-month follow-up (p<0.001).
Conclusions: In this large multicenter cohort of patients with STEMI, thrombus prevalence was 4.1% by CMR. The presence of LV thrombi is associated with decreased myocardial salvage, larger infarcts, and more pronounced reperfusion injury with subsequent significantly increased MACE rates. Consequently, our data underscore the importance of LV thrombi as a marker of poor outcome in STEMI patients.
- © 2013 by American Heart Association, Inc.