# Ventricular Morphology and Outcomes in Fontan Circulation without Hypoplastic Left Heart Syndrome: A Single-Center's Experience

## TL;DR

This study compares long-term outcomes in Fontan patients with right or left ventricle dominance and finds no significant differences in survival or complications.

## Contribution

The study provides new evidence that ventricular dominance does not affect outcomes in Fontan patients without hypoplastic left heart syndrome.

## Key findings

- RV and LV dominance groups had similar 10-year freedom from death or transplantation (84% vs 81%).
- There was no significant difference in Fontan failure rates between RV and LV dominance groups.
- Moderate or greater atrioventricular valve regurgitation was comparable between the two groups.

## Abstract

The impact of dominant ventricular morphology on Fontan
patient outcomes remain controversial. This study evaluates long-term results of
right ventricle (RV) dominance versus left ventricle (LV) dominance in Fontan
circulation without hypoplastic left heart syndrome (HLHS).

We
retrospectively examined 323 Fontan operations from our center. To minimize pre-
and intra-Fontan heterogeneity, 42 dominant RV patients were matched with 42
dominant LV patients using propensity score matching, allowing for a comparative
analysis of outcomes between groups.

The mean follow-up was 8.0
± 4.6 years for matched RV dominant and 6.5 ± 4.7 years for matched
LV dominant group (p
> 0.05), showing no significant difference. The
cumulative incidence of moderate or greater atrioventricular valve regurgitation
was also comparable between the two groups (p
> 0.05). Similarly,
10-year freedom from death or transplantation following the Fontan operation was
84% ± 7% in the matched dominant RV group, similar to 81% ± 7% in
the matched dominant LV group (p
> 0.05). The 10-year freedom from
Fontan failure was 78% ± 8% in the matched dominant RV group, also
similar to 75% ± 8% in the matched dominant LV group (p >0.05). Multivariate analysis did not identify RV dominance as a risk factor for
Fontan failure (p
> 0.05).

In the pre- and
intra-Fontan context, RV dominance demonstrated similar and comparable long-term
outcomes compared to LV dominance in non-HLHS Fontan circulation.