Atrial tachyarrhythmias late after Fontan operation are related to increase in mortality and hospitalization

Background: Atrial tachyarrhythmias are a known complication late after Fontan operation. Limited information is available on their prognostic value.

Methods: All patients with previous Fontan operation followed at our institution since 1999 were identified from the electronic database and included in this study. Demographic and clinical characteristics including history of atrial tachyarrhythmias were recorded at the earliest full clinical assessment and patients were followed thereafter for all-cause mortality and hospitalization.

Results: A total of 98 patients, mean age 31.5 ± 8.9 years, 43.8% male, 31.6% with a total cavopulmonary connection (TCPC) were identified. A history of atrial tachyarrhythmia was present at baseline in 60.2% of patients who were older (33.0 ± 8.3 vs 29.1 ± 9.4 years, p=0.002), less likely to have a TCPC (13.5% vs 58.9%, p<0.001), and more symptomatic in terms of NYHA class (51.9% vs 26.7%, p=0.007) compared to arrhythmia-free patients. During a median follow-up of 6.7 years 18 patients died and 64 patients were hospitalized. Even after adjustment for baseline clinical characteristics, atrial tachyarrhythmia was an independent predictor of death (propensity score adjusted HR 9.35, 95% CI: 1.10-79.18, p=0.04, c-statistic 0.88) and composite of death or hospitalization (propensity score adjusted HR 5.00, 95% CI: 2.47-10.09, p<0.0001).

Conclusions: In adult patients with a Fontan-type operation, the presence of atrial tachyarrhythmias is associated with higher morbidity and mortality at mid-term follow-up. Whether early arrhythmia targeting intervention may improve clinical outcome needs to be studied in a prospective manner.