Abstract 4142149: A 10 Year Report on Fontan Candidacy

Background: As patients progress through the single ventricle palliation, changing hemodynamics and non-cardiac conditions can prevent completion of Fontan. We sought to determine the incidence of completion of Fontan at our institution and to investigate the reasons for non-Fontan candidacy. Methods: Institutional database was queried to identify patients who underwent single ventricle palliation from 2010 to 2020. Patients who underwent stage 2 palliation were included for analysis. The primary outcome of interest was reason for non-Fontan candidacy or reason for delayed Fontan. Results: 526 patients who reached stage 2 single ventricle palliation were analyzed. 378 (71.9%) underwent Fontan procedure or were referred for Fontan before the age of 4-years-old at our center at the time of the study (Figure 1). 19 patients died prior to the typical age of Fontan and 38 were lost to follow up. Of the remaining 91 patients, 21 (23.1%) had a 1.5 or 2 ventricle repair, 12 (13.2%) had a Fontan at another center, and 29 (32%) had a late Fontan. Most patients with late Fontan were due to provider practice variation (22), whereas there were only 3 patients with medical conditions delaying pre-Fontan testing, and 4 patients had a Kawashima. Only 3 patients out of the 12 who had Fontan at another center were for second opinions, whereas the remainder either moved or had surgery at another center due to family preference. Reasons for non-Fontan candidacy were divided into cardiac and respiratory sources. Cardiac reasons included severely depressed ventricular function (12), diastolic dysfunction (2), atrioventricular valve stenosis or regurgitation (7), and pulmonary vein stenosis (3). Respiratory conditions leading to non-Fontan candidacy included severe OSA (1), pulmonary arterial malformation (1), and pneumonectomy (2). There are 17 patients in the non-candidacy group who had a heart transplant or were listed for transplant at the time of the study. No patient in our study was deemed not a candidate for Fontan after stage 2 palliation for developmental delay or syndrome. Discussion: This study demonstrates that the reasons for non-Fontan candidacy after completion of stage 2 palliation are broadly due to hemodynamic and respiratory condition, with many patients who are not candidates developing severe ventricular dysfunction after stage 2. There is a subset of patients who either move, are lost to follow up, or are delayed due to provider practice variation.