Fontan Palliation in Patients with Heterotaxy Syndrome: A Five Decade Experience.

Background: Patients with heterotaxy syndromes (right and left atrial isomerism) are at high risk of poor outcomes after single-ventricle palliation. However, the long-term outcomes and specific parameters associated with poor outcomes are incompletely understood.

Methods: A retrospective review was performed of all patients with atrial isomerism who had a Fontan at our institution from 1973 to 2020. Standard demographic, as well as pre-, peri-, and postoperative parameters were collected. Features and outcomes of patients with polysplenia were compared to asplenia. Outcomes were analyzed for effect during 4 eras: (1: 1973-1984; n = 27), (2: 1985-1994; n = 93), (3: 1995-2004; n = 28), and (4: 2005-2020; n = 10).

Results: Of the 1176 patients who had a Fontan operation, 158 (14%) had a heterotaxy syndrome. The median age at the time of Fontan was 8 (9) years. Early mortality was 20% and was greater in patients with asplenia compared to polysplenia (27% vs. 12%,  = .019). But it substantially improved over time (61% in era 1 vs. 7%-10% in the more recent eras ( < .001)), as did transplant-free survival (22% at 10 years in era 1 vs. 88% in era 4,  < .001). Transplant-free survival was significantly lower in patients with asplenia versus those with polysplenia ( = .014), and patients with heterotaxy had lower survival than nonheterotaxy ( = .01). This was largely due to the asplenia group ( < .001) (hazard ratio = 3.05,  = .007).

Conclusions: After Fontan operation, patients with heterotaxy, particularly asplenia, continue to demonstrate worse transplant-free survival than nonheterotaxy patients. Early mortality and long-term transplant-free survival have improved in more recent eras.