Impact of diaphragm paralysis and its surgical interventions on outcomes after the staged Fontan procedure.

Objectives: This study aimed to investigate the incidence of diaphragm paralysis and its impact on outcomes after the Fontan procedure in patients with single ventricles.

Methods: Patients undergoing staged Fontan palliation between 1994 and 2023 were reviewed. Patients who had diaphragm paralysis were identified, and the impact of diaphragm paralysis on outcomes after Fontan completion was evaluated.

Results: Among 601 patients who underwent staged Fontan completion during the study period, diaphragm paralysis was observed in 79 patients (13.1%) before Fontan (33 after stage I palliation and 46 after Glenn) and in 32 patients (5.3%) after the Fontan. Among 111 patients with diaphragm paralysis, 77 had spontaneous recovery, 13 recovered after plication and 21 remained without recovery. Patients with diaphragm paralysis before the Fontan demonstrated higher pulmonary arterial pressure (median 10 vs 9 mmHg, P = 0.045) and lower pulmonary artery symmetry index (median 0.54 vs 0.59, P = 0.046) than those without diaphragm paralysis. The use of an autologous pericardial patch in stage 1 was a risk factor for diaphragm paralysis development (odds ratio: 2.61, P = 0.012). Diaphragm paralysis was associated with an increased risk of protein-losing enteropathy (hazard ratio: 2.31, P = 0.003), particularly in patients without recovery after plication (hazard ratio: 4.85, P = 0.031).

Conclusions: Diaphragm paralysis following Fontan completion significantly increases the risk of protein-losing enteropathy and long-term mortality, particularly in patients who fail to recover after plication. Early identification and appropriate management of diaphragm paralysis may be crucial for optimizing outcomes.