# Outcomes of Cardiac Repair in Heterotaxy Syndrome Patients—Tertiary Center Experience

## TL;DR

This study examines outcomes and risk factors in patients with heterotaxy syndrome who underwent cardiac repair, focusing on mortality and arrhythmia.

## Contribution

The study identifies risk factors for mortality and arrhythmia in HS patients based on atrial isomerism and repair type.

## Key findings

- Patients with right atrial isomerism had a higher mortality rate compared to those with left atrial isomerism.
- Pulmonary venous anomalies were more common in patients with right atrial isomerism.
- Lower initial operation age was a significant risk factor for mortality.

## Abstract

This study aims to determine factors associated with poor outcomes and frequency of arrhythmia incidence in patients with heterotaxy syndrome (HS).

A retrospective cohort study in a single tertiary center was conducted and included patients with operated HS between 2011 and 2020. A total of 52 patients were included. Relevant factors associated with mortality that were considered included univentricular (UV) or biventricular (BV) physiology, prematurity, low weight/age at surgery, the presence of atrioventricular valve regurgitation, anomalous pulmonary veins drainage, and type of atrial isomerism.

Thirty-three patients (63.4%) were diagnosed with left atrial isomerism (LAI), whereas the remaining 19 (36.5%) were diagnosed with right atrial isomerism (RAI). Thirty-eight patients (73%) underwent UV repair, whereas 14 patients (27%) had BV physiology. Patients were followed up for an average of 4.8 years. Lastly, 14 patients (27%) had died during the follow-up period. Notably, most patients with complete repair are among the LAI group, and high-grade heart block only occurred in patients with LAI. Moreover, patients with LAI were more likely to receive BV repair, whereas patients with RAI were more likely to undergo UV repair (P = 0.008). In addition, pulmonary venous anomalies occurred more frequently among the RAI group. Expectedly, nonsinus rhythm was frequently present among the cohort. Finally, the mortality rate was significantly higher among the RAI group (42% vs 18%, P = 0.06).

Managing HS patients with UV physiology still remains a challenge. Risk factors for mortality included lower initial operation age, and RAI approached significance. These data may assist with risk stratification and patient counseling.