Myocardial viability under various ischemic burdens in chronic total occlusions: A stress-cardiac magnetic resonance study

Abstract

Objectives: This study aimed to analyze each myocardial segment's ischemic burden, scarring, function, and viability by late gadolinium enhancement (LGE) imaging and stress-MRI using adenosine. Materials and methods: Semi-quantitative and qualitative parameters of myocardial segments were obtained by stress-MRI. Moreover, segments without perfusion defect were defined as the no ischemic group, segments with a perfusion defect of ≤50% were defined as a low ischemic burden group, and segments with a perfusion defect of >50% were defined as a high ischemic burden group. “Segmental wall thickening (SWT)” was defined as the absolute difference between the end-diastolic and end-systolic wall thickness. Finally, viability was defined by dysfunctional myocardium (50%. Among the different ischemic burden groups, there were significant differences in LGE volume (p ​ ​0.05). Conclusions: Stress MRI parameters can accurately and detailly assess myocardial viability and function, so multi-parameter joint assessment of CTO patients by stress MRI may help in treatment decisions.

Keywords

• Chronic total occlusion
• Myocardial ischemic burden
• Myocardial viability
• Stress cardiac magnetic resonance
• Late gadolinium enhancement