Longitudinal changes in ventricular function and atrioventricular valve failure following cardiac morphology after Fontan procedure.

BACKGROUND

Ventricular dysfunction and atrioventricular valve (AVV) failure in Fontan patients are associated with adverse long-term outcomes; however, data on longitudinal changes and their relationship with morphology are lacking. This study aimed to describe longitudinal changes in ventricular function and AVV regurgitation and to determine the risk factors in Fontan patients who develop ventricular dysfunction and AVV failure.

METHODS

We retrospectively reviewed echocardiographic images from patients who underwent Fontan procedure from 1984 to 2015. Mixed-effects model fits a unique linear regression line using serial ejection fraction (EF) and AVV regurgitation. Multivariate logistic regression was performed to find morphologic risk factors for ventricular dysfunction and AVV failure.

RESULTS

Out of 174 patients who underwent 3,203 echocardiograms, a significant 6.2% decrease in EF was observed (P<0.001) over a median follow-up of 17.6 years (interquartile range, 15.3-19.2 years) post Fontan procedure. Higher prevalence of ventricular dysfunction (EF <50%) was noted in dominant right ventricle (RV) and two-ventricular (2V) morphologies compared to left ventricle (LV) (P<0.001). AVV failure was more common in RV and 2V morphologies as well (P<0.001). Notably, patients with tricuspid valve (TV) and common AVV exhibited the most pronounced AVV failure (P<0.001). In multivariate analysis, RV, TV and common AVV were correlated with AVV failure (hazard ratio 5.37, 8.24 and 5.43, respectively).

CONCLUSIONS

Fontan patients with long-term follow-up showed a progressive decline in ventricular and AVV function. Dominant RV, TV and common AVV were prognostic factors for predicting AVV failure. Further studies are warranted to explore and validate these findings.