Native T1 mapping in diffuse myocardial diseases using 3-Tesla MRI: An institutional experience

Abstract

Aims: Newer cardiac magnetic resonance techniques like native T1 mapping are being used increasingly as an adjunct to diagnose myocardial diseases with fibrosis. However, its full clinical utility has not been tested extensively, especially in the Indian population. The purpose of this study was to find native T1 values in healthy individuals without cardiac disease in our 3-Tesla MRI system and examine whether native myocardial T1 values can be used to differentiate between normal and diffuse myocardial disease groups. Subjects and Methods: After approval from the institutional ethics committee, native T1 mapping was performed in 12 healthy individuals without cardiac disease who served as controls and in 26 patients with diffuse myocardial diseases (acute myocarditis ( n = 5), hypertrophic cardiomyopathy (HCM) ( n = 8), nonischemic dilated cardiomyopathy (DCM) ( n = 7), restrictive cardiomyopathy (RCM) due to amyloidosis ( n = 6)) in a 3-Tesla MRI system in short axis slices and four-chamber view using a modified Look-Locker inversion recovery sequence. The mean native T1 values and standard deviations were calculated for control and disease groups and compared. The ability of native myocardial T1 mapping to differentiate between normal and diffuse myocardial disease groups was assessed. One-way ANOVA with Tukey's Post-Hoc test was used to find significant difference in the multivariate analysis and Chi-Square test was used to find the significance in categorical data. Results: The native T1 values for the healthy group in our 3-Tesla MRI system was 1186.47 ± 45.67 ms. The mean T1 values of the groups acute myocarditis (1418.68 ± 8.62 ms), HCM (1355.86 ± 44.67 ms), nonischemic DCM (1341.31 ± 41.48 ms), and RCM due to amyloidosis (1370.37 ± 90.14 ms) were significantly higher ( P = 0.0005) than that of the healthy control group. Conclusion: Native myocardial T1 mapping is a promising tool for differentiating between healthy and diffuse myocardial disease groups.

Reference Values of Native T1 at 3T Cardiac Magnetic Resonance—Standardization Considerations between Different Vendors

“…By drawing a ROI in the area of interest. We preferred using endocardial and epicardial contours for the entire slice being analyzed; afterwards, the ROIs were forwarded to all the 8 images, with eventual adjustments in their position depending on respiratory variation between images, and the software returned the T1 values (ms), according to the exponential curve of the respective type of T1 mapping sequence ( Figure 1 ) [ 7 , 18 , 19 , 20 ].…”