Echocardiographic Algorithm for Post-Myocardial Infarction LV Thrombus: A Gatekeeper for Thrombus Evaluation by Delayed Enhancement CMR

• Published in: JACC. Cardiovascular imaging 2016-05, Vol.9 (5), p.505-515
• Main Authors: Weinsaft, Jonathan W, Kim, Jiwon, Medicherla, Chaitanya B, Ma, Claudia L, Codella, Noel C F, Kukar, Nina, Alaref, Subhi, Kim, Raymond J, Devereux, Richard B
• Format: Article
• Language: English
• Subjects: Adult; Aged; Algorithms; Contrast Media - administration & dosage; Echocardiography - methods; Female; Heart Aneurysm - diagnostic imaging; Heart Aneurysm - epidemiology; Humans; Image Interpretation, Computer-Assisted - methods; Magnetic Resonance Imaging, Cine; Male; Middle Aged; Myocardial Infarction - diagnostic imaging; Myocardial Infarction - epidemiology; Myocardial Infarction - physiopathology; Predictive Value of Tests; Prevalence; Prognosis; Prospective Studies; Referral and Consultation; Reproducibility of Results; Stroke Volume; Thrombosis - diagnostic imaging; Thrombosis - epidemiology; Thrombosis - physiopathology; Unnecessary Procedures; Ventricular Function, Left
• ISSN: 1876-7591
• DOI: 10.1016/j.jcmg.2015.06.017

The goal of this study was to determine the prevalence of post-myocardial infarction (MI) left ventricular (LV) thrombus in the current era and to develop an effective algorithm (predicated on echocardiography [echo]) to discern patients warranting further testing for thrombus via delayed enhancement (DE) cardiac magnetic resonance (CMR). LV thrombus affects post-MI management. DE-CMR provides thrombus tissue characterization and is a well-validated but an impractical screening modality for all patients after an MI. A same-day echo and CMR were performed according to a tailored protocol, which entailed uniform echo contrast (irrespective of image quality) and dedicated DE-CMR for thrombus tissue characterization. A total of 201 patients were studied; 8% had thrombus according to DE-CMR. All thrombi were apically located; 94% of thrombi occurred in the context of a left anterior descending (LAD) infarct-related artery. Although patients with thrombus had more prolonged chest pain and larger MI (p ≤ 0.01), only 18% had aneurysm on echo (cine-CMR 24%). Noncontrast (35%) and contrast (64%) echo yielded limited sensitivity for thrombus on DE-CMR. Thrombus was associated with stepwise increments in basal → apical contractile dysfunction on echo and quantitative cine-CMR; the echo-measured apical wall motion score was higher among patients with thrombus (p < 0.001) and paralleled cine-CMR decrements in apical ejection fraction and peak ejection rates (both p < 0.005). Thrombus-associated decrements in apical contractile dysfunction were significant even among patients with LAD infarction (p