Cardiac surgery in patients with atrial isomerism: Long-term results and outcomes.

PURPOSE The aim of the study was to identify, determine, and analyze the clinical and surgical outcomes of patients with atrial isomerism (AI) undergoing cardiac surgery. METHODS A retrospective study was carried out. Patients with diagnosis of AI undergoing cardiac surgery at the National Institute of Cardiology Ignacio Chavez, from January 1, 2010 and March 31, 2020 were included; demographic characteristics and perioperative conditions of the patients were considered. RESULTS Sixty-five patients were included, with an average age of 6.4 ± 4.9 years, 50.8% males. Thirty-eight (58.5%) had right atrial isomerism (RAI) and 27 (41.5%) had left atrial isomerism (LAI); univentricular physiology (78.5%) predominated. Atrioventricular septal defect (AVSD) in RAI and septal defects in LAI were identified as the main associated defects. The most common surgical procedures performed were modified Blalock-Taussig shunt (MBTS) (27.6%), MBTS with total anomalous pulmonary venous connection (TAPVC) repair (15.3%) and total cavopulmonary connection (TCPC) with an extracardiac conduit fenestrated (10.8%); 100% RAI required a univentricular approach, while in LAI it was 48.1%. Overall survival was 92.3%, with 100% survival in LAI with biventricular physiology and 86.8% in RAI with univentricular physiology. CONCLUSIONS The survival of our institution is similar to that of other referral centers, where patients with LAI had a better evolution than RAI; in addition, the univentricular approach was required in all with RAI. Patients with AI must undergo a rigorous evaluation to determine an adequate repair strategy, considering univentricular RAI with a high possibility of morbidity and mortality.