Right ventricular native T1 (HR 1.15; 95% CI 1.07-1.25; p<0.001) and left ventricular LGE independently predicted adverse cardiovascular outcomes in adults with repaired tetralogy of Fallot.
Cohort (n=201)
Does myocardial and hepatic T1 relaxometry on CMR predict adverse cardiovascular outcomes in adults with repaired tetralogy of Fallot?
Diffuse myocardial fibrosis in the right ventricle and replacement fibrosis in the left ventricle assessed by CMR are independent predictors of major adverse cardiovascular outcomes in adults with repaired tetralogy of Fallot.
Effect estimate: HR 1.15 (95% CI 1.07-1.25)
p-value: p=<0.001
BACKGROUND: Cardiovascular magnetic resonance imaging (CMR) can estimate diffuse myocardial fibrosis using native T1 mapping and extracellular volume fraction (ECV) quantification. OBJECTIVES: This study aimed to explore associations between, and prognostic value of, myocardial and hepatic parametric imaging measurements after tetralogy of Fallot repair (rTOF). METHODS: Adults with rTOF were prospectively enrolled along with healthy controls. Patients were categorized by residual hemodynamic load (pulmonary stenosis and/or pulmonary regurgitation). Available clinical data were recorded at study entry. Myocardial and hepatic native T1 were measured and ECV was calculated from pre/post-contrast T1 maps. The primary outcome was a composite of death, resuscitated sudden death, sustained ventricular tachycardia (VT), VT requiring invasive therapy, or heart failure requiring hospital admission. Multivariable models, adjusted for age and sex, examined the association between CMR measures and adverse cardiovascular events. RESULTS: In total, n=181 patients (56% male; median age 33 years IQR 26-47) and 20 healthy age and sex-matched controls were studied. Hepatic and myocardial ECV measures correlated modestly (r=0.31, p<0.001). Hepatic native T1 was higher in rTOF patients as compared with controls (572±102 versus 529±12 msec, p=0.006) with statistically significant differences between hemodynamic load type (p=0.044). Right ventricular (RV) native T1 was increased in rTOF as compared with controls (1078±43 versus 997±43 msec, p<0.001) with a trend towards significant differences when stratified by hemodynamic load (p=0.091). Pathologic late gadolinium enhancement (LGE) was seen in the RV in 46% (n=83) and in the left ventricle (LV) in 37% (n=66). At median follow-up 2.05 years (IQR 0.75-2.81), the composite primary outcome occurred in 9% (n=17). Independent predictors of adverse events included RV end-systolic volume (HR 1.43, 95% CI 1.09-1.99, p=0.009), RV native T1 (HR 1.15, 95% CI 1.07-1.25, p<0.001) and LV LGE (HR 3.18, 95% CI 1.07-10.23, p=0.038); hepatic parametric imaging was not associated with outcome. CONCLUSION: In rTOF, myocardial and hepatic parametric imaging measures were modestly correlated and were increased as compared with controls. Diffuse myocardial fibrosis in the RV (native T1) and replacement fibrosis in the LV (LGE) were independently associated with major adverse cardiovascular outcomes, although hepatic relaxometry measures were not. These findings warrant further validation in larger populations with longer follow-up.
Ishikita et al. (2026) conducted a cohort in Repaired tetralogy of Fallot (n=201). Cardiovascular magnetic resonance imaging (native T1 mapping and ECV) vs. Healthy controls was evaluated on Composite of death, resuscitated sudden death, sustained ventricular tachycardia (VT), VT requiring invasive therapy, or heart failure requiring hospital admission (HR 1.15, 95% CI 1.07-1.25, p=<0.001). Right ventricular native T1 (HR 1.15; 95% CI 1.07-1.25; p<0.001) and left ventricular LGE independently predicted adverse cardiovascular outcomes in adults with repaired tetralogy of Fallot.