Clinical Significance Myocardial Extracellular Volume Quantification by Cardiac Computed Tomography in Cardiomyopathy: Comparison with Magnetic Resonance Imaging

Myocardial extracellular volume (ECV) is an important parameter for assessing the pathophysiology of cardiomyopathy, and cardiac magnetic resonance imaging (CMR) is established as the standard technique for its measurement. However, CMR has several clinical limitations, creating a need for alternative imaging modalities. Cardiac computed tomography (CT) has emerged as a potential alternative. The primary aim of this study was to directly compare the accuracy and agreement of myocardial ECV measured by cardiac CT (CT-ECV) and by CMR (MRI-ECV) in the same patient cohort. In this retrospective study, 44 patients were included, all of whom underwent both cardiac CT and CMR. Statistical analyses, including paired t-tests and Pearson correlation, were performed to compare ECV values obtained by the two techniques. In the overall cohort, the mean MRI-ECV was 26.27%, and the mean CT-ECV was 26.57%. The mean difference between the two modalities was not statistically significant (p = 0.279). A strong positive correlation was observed between CT-ECV and MRI-ECV values (r = 0.776). CT-ECV demonstrated a high degree of correlation and agreement with the CMR reference standard, suggesting that CT-ECV may serve as a reliable, accurate, and clinically practical alternative for myocardial tissue characterization in patients with cardiomyopathy.