Long-Term Outcomes and Arrhythmia Risk After Total Cavopulmonary Connection: A Single-Center Cohort Study

All articles of this category (opens in new window) Background: Outcomes of single-ventricle patients undergoing the Fontan operation have improved over the past decades, yet morbidity and late mortality remain a significant concern. Arrhythmias are among the most frequent complications of Fontan physiology. We aimed to evaluate survival and arrhythmia incidence after total cavopulmonary connection (TCPC) in a large single-center cohort. Methods: Medical records of patients undergoing TCPC between 1996 and 2018 were reviewed. Survival, freedom from heart transplantation or takedown, and freedom from arrhythmia were assessed. Results: A total of 383 patients (240 males, 143 females) were included. Right ventricular morphology was present in 253 (66.1%), with hypoplastic left heart syndrome being the most common ( n = 200, 52.2%) diagnosis. Median age at surgery was 2.7 (IQR: 2.3–3.2) years. The intra-atrial lateral tunnel technique was used in 341 (89.0%) cases. Early failure occurred in 5 (1.3%) patients (four deaths and one takedown). Median follow-up for hospital survivors was 12.6 (IQR: 8.2–17.3) years. Freedom from death, transplant, or takedown was 98%, 96%, and 88% after 5, 10, and 20 years. Freedom from any arrhythmia was 91% after 10 years, with a steeper decline observed thereafter; arrhythmia-free survival was 73% at 20 years. Atrial tachyarrhythmias were the most common (72.0%). Freedom from pacemaker implantation was 90% at 20 years. Compared with all other lesions, Double-Inlet-Left-Ventricle carried a higher risk for pacemaker requirement. In univariate analysis, male gender was associated with increased arrhythmia risk beyond 10 years after TCPC (HR: 2.927, 95% CI: 1.170–7.321, p = 0.022). Additional risk factors included unbalanced AVSD, right atrial isomerism, and concomitant surgery at TCPC. Early postoperative tachyarrhythmias predicted later arrhythmic events, particularly within 2 years after TCPC. Pacemaker implantation before or during TCPC hospitalization was associated with late arrhythmia risk. Conclusion: Long-term outcomes following TCPC in this large single-center cohort are favorable. However, arrhythmias remain a major late complication, particularly beyond 10 years postoperatively. The elevated risk for arrhythmias in males after the onset of puberty suggests a role of sex steroid hormones in arrhythmia susceptibility. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany