Reply to "Letter on: Reduced Perfusion Pressure as a Predictor of Protein-Losing Enteropathy After Fontan Procedure: Beyond Central Venous Pressure".

We thank Dr. Shah for his insightful commentary on our report identifying reduced perfusion pressure (PP) as a predictor of protein-losing enteropathy (PLE) after the Fontan procedure. We agree that PP is an indirect marker and that Fontan-associated PLE is multifactorial, with gut dysbiosis among its contributors. We propose, however, that these downstream changes share a common upstream origin-the chronic hemodynamic burden of the Fontan circulation-and outline an integrated, multidisciplinary approach to clarifying the mechanisms of PLE.