T1 and T2 Mapping Assessment in Chronic Chagas Cardiomyopathy: Pilot Experience in a Latin American Center (RF_SA_457)

Cardiac Magnetic Resonance (CMR) provides critical diagnostic information to assess tissue characteristics in Chronic Chagas cardiomyopathy patients. However, access to parametric mapping in developing countries is limited. T1/T2 mapping measurements have been linked to prognostic value in non-ischemic Cardiomyopathies. Including parametric mapping in Chagas’ Disease might provide better insides to disease progression and physiopathology and provide further disease knowledge.
Our objetive is 

evaluate myocardial T1 and T2 mapping values in patients with Chronic Chagas Cardiomyopathy compared to healthy volunteers as a first assessment in . a single center

Methods:

Patients with Chronic Chagas Cardiomyopathy referred for a CMR exam were recruited. CMRs were performed on a 1.5 T Philips Ingenia scanner, and T1 and T2 mapping were included in the analysis. Normal values were obtained from a separate institutional pilot study involving 20 healthy volunteers. T1 mapping was performed using an electrocardiographically triggered single-shot modified Look-Locker inversion-recovery (MOLLI) sequence, and T2 mapping was done with a gradient-spin-echo (GraSE) sequence. T1 and T2 evaluation involved drawing endocardial and epicardial contours with measurements taken from basal, mid, apical short-axis slices. Descriptive statistics were used, and a student’s t-test was conducted to compare values between groups.

Results:

Nine patients were enrolled in this study (mean age 62.4±9.7 years; [67% n= 6 women]). The mean indexed end-diastolic volume was 118±29.1 mL/m², and the left ventricular ejection fraction was 60±12.9%. Four patients had apical aneurysms or microaneurysms, and one presented with an intraventricular thrombus. The mean global T1 and T2 values within the healthy cohort were 1034±119 ms and 52.8±8.23 ms, respectively. In the Chagas group, the mean global T1 relaxation time was 1043±45.9 ms, and the T2 relaxation time was 58.1±3.8 ms. A Student's t-test revealed no significant difference between the T1 values of the two groups (p< 0.586). However, the groups had a significant difference in T2 values (p< 0.045) (Figure 1)

Conclusion:

In our cohort, Global T1 values were not significantly different from those of healthy controls. In contrast, significant differences were found in T2 values, indicating that T2 mapping might be a better marker of disease than T1 in CCC patients, especially considering the chronic inflammatory process in Chagas disease. Further studies are needed to confirm these findings.