Reduced Perfusion Pressure as a Predictor of Protein-Losing Enteropathy After Fontan Procedure: Beyond Central Venous...

Protein-losing enteropathy (PLE) is a significant complication that affects the prognosis of Fontan patients. Although elevated central venous pressure (CVP) is associated with PLE, some patients develop PLE without elevated CVP. This study aimed to identify whether reduced perfusion pressure (PP), calculated as the mean systemic arterial pressure minus CVP, is a predictor of PLE and assess the impact of angiotensin-converting enzyme inhibitor (ACEI) use on PLE incidence. A retrospective analysis of 107 post-Fontan patients aged < 10 years who underwent catheterization between 1998 and 2021 was performed. The primary endpoint was freedom from PLE. Freedom from the endpoint and significant clinical and hemodynamic predictors, including PP and ACEI use, were analyzed. During a median follow-up of 11.4 years, seven patients (6.5%) developed PLE, with a median onset at 3.8 years. Patients with PP < 60 mmHg showed significantly shorter freedom from PLE, and PP remained a significant predictor in the multivariate analysis considering most of the other variables, including CVP. ACEI use was a significant predictor for PLE but did not remain significant after adjustment for fenestration at Fontan, brain natriuretic peptide, pulmonary artery index, ejection fraction, and end-diastolic ventricular volume of the single ventricle. PP was a significant predictor of PLE development in the post-Fontan hemodynamic evaluation, independent of CVP. PP warrants consideration alongside CVP in the hemodynamic assessment of Fontan circulation. Although ACEI use was associated with PLE development in the univariable analysis, the present data do not establish ACEI use as an independent risk factor, given the potential for indication bias in the ACEI-treated group.