Risk factors for the development of arrhythmias after the fontan surgery

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Fontan surgery or total cavopulmonary connection is a palliative procedure for complex congenital heart disease with univentricular physiology, without the possibility of biventricular surgical correction. This surgery has a high mortality rate (70%), with heart failure and arrhythmias being the main causes of death. Objective Identify the pre, intra and post-surgical factors that may predispose to arrhythmias in patients undergoing to Fontan surgery. Methods We conducted a retrospective review of the patients who underwent a total cavopulmonary connection from January 2003 to December 2018. We performed an analysis employing the Chi-square test to determine which variables were associated with the development of arrhythmias. Results During the mentioned period, 115 patients underwent to Fontan surgery, of which 51.3% were women, the average age at the time of surgery was 8 years. The most frequent diagnosis was tricuspid atresia in 44 patients (38.2%), followed by pulmonary atresia in 18 patients (15.7%) and double outlet right ventricle in 14 patients (12.2%). Regarding the type of the procedures performed, 93.9% (n = 108) were total extracardiac cavopulmonary connection and 6.1% (n = 7) were intracardiac. Also, 8.6% (n = 10) were taken to fenestration, the mean size of the fenestration was 7 mm (7 ± 3 mm) After Fontan surgery, there was a high incidence of arrhythmias which was 38% (n = 44). 22 patients (50%) presented them in the late postoperative period, being this, the most frequent time for the appearance of arrhythmias. We found that the intracardiac surgery presented an OR of 4.423 (95% CI 0.819 - 23.879, p> 0.05), being not statistically significant. Instead, the bidirectional cavopulmonary shunt previous to the Fontan surgery presented an OR of 0.255 (95% CI 0.081 - 0.806, p <0.05) and on the other hand the QRS duration > 120 ms was significantly associated with the appearance of arrythmias with an OR 2.99 (95% CI 1.2-4.2, p <0.05). Conclusions In patients undergoing to Fontan surgery, the previous bidirectional cavopulmonary bypass is a protective factor for the development of arrhythmias. And an QRS duration > 120 ms is a parameter that predicts the apparence of arrhythmias. Abstract Figure. QRS INTERVAL POST FONTAN SURGERY