Arrhythmias after Fontan surgery
Fontan operation was originally described in 1971. Ever since several modifications have been introduced. In general they involve a univentricular type of repair. Atrial arrhythmias are an important cause of morbidity and mortality in the long term history of Fontan operations. Stephenson EA and associates (J Am Coll Cardiol, 2010; 56:890-896) evaluated a large Fontan cohort of 520 patients across 7 centers over a mean period of 8.6 years with medical history, echocardiogram, electrocardiogram, exercise testing and parent-reported Child Health Questionnaire (CHQ). They documented supraventricular tachycardia in 9.4% of the patients, of which 7.3% ( thirty two of five hundred and twenty) was intra atrial re-entrant tachycardia (IART). They noted a bimodal risk pattern for IART in these children. Initially the risk decreased for four to six years after the Fontan surgery and then increased as the age advances. Resting heart, including profound bradycardia and cardiac anatomy did not influence the risk for IART. Associations for the time of occurrence of IART were lower CHQ physical summary score, predominant rhythm (highest risk with paced rhythm) and the type of Fontan operation (maximum risk with atriopulmonary connection). There was no difference in the time to the development of IART between patients with lateral tunnel and extracardiac conduits in Fontan operation. 3.5% of patients had ventricular tachycardia in this Fontan cohort. The authors concluded that the overall prevalence of IART was lower in this series than that has been reported earlier.
Other than arrhythmias, the major late problems after Fontan repair include extra cardiac conduit obstruction, left pulmonary artery obstruction, ventricular failure and protein losing enteropathy (J Am Coll Cardiol, 2006; 47:2065-2073).