Comparison of Septal Region-of-Interest and Whole-Myocardium Contouring Methods for Myocardial T1 Measurement in Metabolic Syndrome

Metabolic syndrome (MetS) is a global public health challenge associated with an increased risk of cardiovascular disease and all-cause mortality. Cardiac magnetic resonance (CMR) T1 mapping enables non-invasive quantitative assessment of myocardial tissue characteristics and facilitates detection of diffuse myocardial remodeling in MetS. However, whether T1 quantification in patients with focal late gadolinium enhancement (LGE) should exclude scar regions remains controversial. This study compared T1 values obtained using a septal region-of-interest (ROI) method that avoids LGE lesions with those obtained using conventional whole-myocardium contouring and evaluated their predictive performance for major adverse cardiovascular events (MACE). A retrospective cohort of 207 patients with MetS who underwent 3.0 T CMR, including T1 mapping and LGE imaging, was evaluated. Native and post-contrast T1 values were measured using the septal ROI method and semi-automated whole-myocardium contouring. Paired t-tests were used to compare measurements, receiver operating characteristic curves were used to evaluate MACE prediction, and intraclass correlation coefficients (ICCs) were used to assess reliability. Native T1 values did not differ significantly between methods (1253.07 ± 218.27 ms vs. 1255.79 ± 261.29 ms, p = 0.748), nor did post-contrast T1 values (270.28 ± 48.66 ms vs. 271.67 ± 55.63 ms, p = 0.469). Both methods showed predictive value for MACE, with no significant difference in predictive performance. Inter-method ICCs were 0.873 and 0.860 for native and post-contrast T1, respectively, and inter- and intra-observer ICCs exceeded 0.93. The septal ROI method yielded T1 measurements similar at the group level to those obtained with whole-myocardium contouring, with no statistically significant difference in prognostic performance, while requiring less extensive image analysis.