Background: Total anomalous pulmonary venous connection (TAPVC), is a congenital heart defect that requires surgical repair shortly after diagnosis. Post-surgical arrhythmias are expected complications of TAPVC surgical repair. Few data exist on the incidence of arrythmias after TAPVC repair in Guatemala. Therefore, we sought to determine the short- and long-term incidence of and risk factors for arrhythmias in patients undergoing TAPVC repair at our institution.

Methods: We performed a retrospective longitudinal study of all patients with TAPVC, either isolated or associated with other simple cardiovascular anomalies (RACHS score 1 or 2), who underwent surgical correction between 2007-2017 at the Cardiovascular Surgery Unit of Guatemala. Patients who died before discharge were excluded. The primary outcomes were arrhythmias in the immediate post-operative period and after hospital discharge. Descriptive statistics and chi-squared analyses comparing the percentage of arrhythmias by TAPVC type, cardiopulmonary bypass time, and type of atriotomy were performed.

Results: A total of 86 patients, 58% male, were included. Median age at diagnosis was 3 months (IQR 1 – 9 months), and at time of surgery was 5 months (IQR 2 – 25 months). Arrhythmia incidence was 60% (52) in the immediate post-operative period and 30% (26) after discharge. Supraventricular arrythmias were the most common post-operatively (25, 48%) and after discharge (13, 50%). Most of these were ectopic atrial tachycardia (18, 21%, immediately and 10, 12%, after discharge). One patient (1%) developed complete heart block immediately post-operatively requiring a pacemaker, and one (1%) required a pacemaker for sinus node dysfunction after discharge. TAPVC type was not associated with arrhythmia incidence immediately post-operatively. Patients with supracardiac TAPVC had a greater arrhythmia incidence after discharge (p<0.001). Longer cardiopulmonary bypass time was associated with greater arrhythmia incidence (immediate post-operative period mean 75 min (SD 28 min) vs. 60 min (SD 26 min), p<0.02; after discharge - 84 min (SD 18 min) vs. 63 min (SD 29 min), p<0.02). Atriotomy type was not associated with arrhythmia immediately post-operatively, but atriotomy perpendicular to the vena cavas was associated with more arrhythmias after discharge (p<0.001).

Conclusions: To our knowledge, this is the first report of the incidence of and risk factors for post-operative arrhythmias after TAPVC repair in Guatemala. Even thought most patients had arrhythmias immediately post-operatively, less than one-third had persisted after discharge. Supracardiac TAPVC, longer cardiopulmomary bypass time, and atriotomy perpendicular to the cavas were associated with postoperative arrhythmias. Our findings shall contribute to the understanding of postoperative arrythmias so that they can be prevented and treated when required.