Effect of Myocardial Viability Assessed by Cardiac Magnetic Resonance on Survival in Patients With Severe Left Ventricular Dysfunction

Area of Science:

• Cardiology
• Cardiovascular Imaging
• Medical Diagnostics

Background:

• Myocardial viability assessment is crucial for revascularization decisions in ischemic heart failure.
• The prognostic utility of cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) remains debated.
• Left ventricular ejection fraction (LVEF) ≤35% defines the study cohort with ischemic heart failure.

Purpose of the Study:

• To evaluate the prognostic value of CMR-LGE for predicting outcomes in ischemic heart failure patients undergoing revascularization.
• To determine if LGE extent influences survival benefit from coronary artery bypass grafting (CABG) versus optimal medical therapy (OMT).

Main Methods:

• Retrospective analysis of 165 ischemic heart failure patients (LVEF ≤35%) who underwent CMR before CABG or OMT.
• Myocardial segments with LGE >50% wall thickness were classified as non-viable.
• Outcomes assessed included all-cause mortality, cardiovascular mortality, and major adverse cardiovascular events.

Main Results:

• A higher number of non-viable myocardial segments correlated with increased all-cause and cardiovascular mortality in the CABG group (P<0.05).
• This association was not significant in the optimal medical therapy (OMT) group (P>0.05).
• Anterior wall viability did not impact patient outcomes.

Conclusions:

• CMR-assessed myocardial viability may identify patients who benefit differentially from CABG.
• These findings suggest LGE could guide revascularization strategies in ischemic heart failure.
• Larger prospective studies are needed to validate these hypotheses.