Prognostic Value of Fatty Metaplasia Detected by Out-of-phase Cine Imaging in Patients with Chronic Myocardial Infarction (RF_FR_364)

Friday, January 31, 2025

2:00 PM – 2:10 PM East Coast USA Time

Location: Blue Room PreFunction

Presenting Author(s)

CC

Céleste Chevalier, MD

Postdoctoral fellow
Duke University Medical Center

Primary Author(s)

CC

Céleste Chevalier, MD

Postdoctoral fellow
Duke University Medical Center

Co-Author(s)

YK

Yodying Kaolawanich, MD

Assistant Professor in Medicine, Cardiology
Siriraj Hospital, Mahidol University, Thailand
MP

Michele Parker, MSc

Statistician / Business Manager
Duke Cardiovascular Magnetic Resonance Center
David C. Wendell, PhD

Senior Research Associate
Duke University Medical Center
HK

Han Kim, MD

Associate Professor of Medicine
Duke University Medical Center
EC

Enn-Ling Chen, PhD

Research Professor
Duke Cardiovascular Magnetic Resonance Center
RK

Raymond J. Kim, MD

Professor of Medicine and Radiology
Duke University Medical Center

Background: Fatty metaplasia can occur in chronic myocardial infarction (MI),(1) and by altering the electrophysiological properties of the myocardium, it may serve as a substrate for ventricular arrhythmias and sudden cardiac death (SCD).(2-5) A recently validated out-of-phase (OOP) SSFP cine technique allows for consistent detection of fatty metaplasia as part of a routine CMR exam without the need for additional image acquisitions.(6,7) The aim of this study was to investigate the prognostic implications of fatty metaplasia detected by OOP-cine imaging in patients with chronic MI.

Methods: We studied 315 patients with a documented clinical diagnosis of chronic MI ( >12 months old) who were referred for clinical CMR. Patients with a history of nonischemic cardiomyopathy were not included. A complete short-axis stack of optimized OOP-cine and delayed enhancement (DE) images were acquired. The primary endpoint was adverse arrhythmia events (sudden cardiac death (SCD) or sustained VT/VF). Secondary endpoints included a composite of heart failure events (heart failure death, cardiac transplantation or left ventricular assist device (LVAD) implantation) and cardiac mortality.

Results: In the overall cohort, the mean age was 65 years, 72% were male, and mean left ventricular ejection fraction (LVEF) was 51%. Fatty metaplasia was present in 165 patients (52%). Figure 1 shows a typical example of fatty metaplasia detected by OOP-cine imaging. During a median follow-up of 4.1 (2.8, 5.2) years, there were 17 cardiac deaths. There were 20 arrhythmia events of which 11 patients had SCD and 9 had sustained VT/VF. There were 6 heart failure events of which 4 patients had heart failure death and 2 had cardiac transplantation / LVAD implantation. Patients with fatty metaplasia had a significantly higher rate of arrhythmia events and cardiac death than those without fatty metaplasia (10.9% vs. 1.3%, HR 7.77 (1.80, 33.54), p< 0.01, and 8.5% vs. 2.0%, HR 3.98 (1.14, 13.86), p=0.03, respectively). Whereas there was a reduced association with heart failure events which was not significant (2.4% vs. 1.3%, HR 1.78 (0.33, 9.70), p=0.51). On survival analysis, fatty metaplasia was strongly associated with arrhythmia events (log-rank test p< 0.01) and cardiac death (p< 0.04) (Figure 2). There was no significant association with heart failure events (p=0.50). In a subgroup of 252 patients with moderate or smaller infarct size (< 20% of LV mass), we again found a significant association of fatty metaplasia with arrhythmia events (log-rank test P< 0.02) (Figure 3).

Conclusion: In patients with chronic MI, the presence of fatty metaplasia detected by OOP-cine imaging is associated with arrhythmia events but not with heart failure events. An assessment of intramyocardial fat with complete LV coverage by OOP-cine imaging can be implemented into the evaluation of patients with chronic MI without the need for additional image acquisition.