Comparative Analysis of Cardiac and Liver Extracellular Volumes in Repaired Tetralogy of Fallot and Fontan (RF_FR_386)

Presenting Author(s)

• Ai

  Adriana m. innocenzi, PhD

  Physician/ Researcher
  IDOR, Brazil

Primary Author(s)

• Ai

  Adriana m. innocenzi, PhD

  Physician/ Researcher
  IDOR, Brazil

Co-Author(s)

• MP

  Mariana Povoa-Correa, MD

  Researcher
  IDOR, Brazil
• FF

  Fernanda Fernandes, MD

  researcher
  IDOR, Brazil
• ES

  Eduardo Schaustz, N/A

  medical student
  IDOR, Brazil
• JS

  Jose Carlos Pizzolante Secco, N/A

  medical student
  IDOR, Brazil
• Gc

  Gabriel camargo, MD, PhD

  Physician
  IDOR, Brazil
• rM

  renata Moll-Bernardes, MD, PhD

  Physician/ Researcher
  IDOR, Brazil

Background:
The survival of patients with congenital heart disease has increased considerably in recent decades; however, these patients are often subjected to palliative procedures or present with residual lesions that require lifelong monitoring. The presence of hypoxia, volume or pressure overload may lead to myocardial and liver fibrosis. Fibrosis is a common histopathological finding in various cardiovascular and liver diseases and is associated with morbidity and mortality. The aim of this study was to compare the presence of diffuse myocardial and liver fibrosis through T1 mapping and extracellular volume (ECV) by magnetic resonance imaging (MRI) in patients with Tetralogy of Fallot (TOF) and patients with univentricular physiology with previous Fontan procedure.



Methods:
A cross-sectional study was conducted in 84 patients: 28 healthy controls, 18 patients with repaired TOF (rTOF), and 38 Fontan cases. Patients underwent cardiac and liver MRI examination with a 3.0-T scanner (MAGNETOM Prisma; Siemens Healthcare, Erlangen, Germany). Cardiac and liver T1 mapping was performed with a modified look-locker inversion recovery (MOLLI) sequence using single-shot SSFP pre-contrast (native) T1 mapping and post-contrast acquisition. ECV was calculated using T1 mapping before and after the administration of a gadolinium-based contrast agent (Dotarem; Guerbet). Images were analyzed using multiplatform commercial software (OsiriX MD; Pixmeo) and Circle CVI42. Variables were summarized as means +/-SD. Comparisons between groups were performed using ANOVA with Bonferroni correction. Correlations between continuous variables were explored with a Pearson correlation coefficient.



Results:
Cardiac extracellular volume (ECV) was significantly higher in the rTOF group (30.41±0.80) and in the Fontan group (28.66±0.45) compared to the control group (22.87±0.35, p < 0.001). However, no significant difference was observed between the Fontan and rTOF groups (p = 0.074). Similarly, liver ECV was elevated in both the rTOF group (37.61±1.90) and the Fontan group (43.95±0.70) compared to controls (29.71±1.06, p < 0.001), with the Fontan group showing a significantly higher liver ECV than the rTOF group (p = 0.001).The correlation between cardiac and liver ECV was evaluated for each group, but no significant correlation was found (control group: p = 0.954; rTOF: p = 0.288; Fontan: p = 0.850).



Conclusion:
Patients with Fontan and rTOF exhibit increased cardiac and hepatic ECV, indicating significant tissue remodeling in these organs. Liver ECV was particularly relevant in Fontan patients, suggesting a central role for progressive liver dysfunction in the clinical course of these patients. ECV may serve as a valuable biomarker for monitoring and prognosis in these patient groups.


Cardiac ECV in controls, patients with rTOF and Fontan

Liver ECV in controls, patients with rTOF and Fontan