Patients With Systemic Right Ventricle Are at Higher Risk of Chylothorax After Cavopulmonary Connections

Chylothorax is a rare but severe complication after pediatric cardiac surgical procedures and is related to significant morbidity and mortality. It is suspected to be more frequent after single-ventricle staged palliation procedures, but focused studies on chylothorax in patients with univentricular heart physiology are scarce.

From January 2008 to December 2016, a total of 289 patients underwent 376 cavopulmonary connection (CPC) procedures over 9 years (superior cavopulmonary connection [SCPC], 199; Fontan completion, 177). Patients were classified according to whether they had a chylothorax (group 1) or not (group 2). Chylothorax was confirmed on a pleural fluid test.

The rate of chylothorax after a CPC procedure was 19.7% (74 of 376): 15.6% after SCPC and 24.3% after Fontan completion. Mean follow-up was 4.3 ± 0.1 years. Systemic right ventricle was more frequent in group 1 than in group 2 (64.9% vs 46%, respectively; p = 0.003). Chylothorax was associated with a higher rate of early reoperation (p = 0.001) and late failure of the CPC (p < 0.001). Late mortality was also more frequent in group 1 than in group 2 (17.6% vs 4.3%; p < 0.001). By multivariate analysis, having a systemic right ventricle was the only identified predictor for the development of chylothorax (odds ratio, 2.49; 95% confidence interval, 1.4 to 4.7; p = 0.004).

The incidence of chylothorax in patients undergoing the univentricular pathway procedure is higher than previously suggested. Having a systemic right ventricle is a significant risk factor for developing a chylothorax after a CPC.