Right atrial isomerism in children older than 3 years

Cardiac Laterality: Surgical Results of Right Atrial Isomerism

Right atrial isomerism (RAI) is a complex entity with varying diagnostic and treatment outcomes due to its rarity. Treatment options range from palliative to corrective surgeries, resulting in heterogeneous outcomes. The aim of this study was to analyze the results obtained after cardiac surgery in patients with RAI. A retrospective study was conducted, including patients diagnosed with RAI who underwent cardiac surgery. Their follow-up was from 1 January 2010 to 31 March 2020. Demographic characteristics and perioperative conditions were described. Thirty-eight patients were included, the median age was 4 years (IQR 2-9.2) and 57.9% were men. The main diagnoses were atrioventricular canal (63.2%) and pulmonary stenosis (55.3%). The most common surgical procedures were modified Blalock-Taussig shunt (65.8%) and total cavopulmonary connection with an extracardiac conduit fenestrated without cardiopulmonary bypass (15.9%). We did not find any factors associated with negative outcomes in these patients. The overall survival was 86.8%, with a better outcome in those who did not require reintubation (log rank, p < 0.01). The survival of RAI was similar to other centers. Individuals with RAI should be evaluated rigorously to determine an adequate repair strategy, considering high morbidity and mortality.

[Isomorfismo cardiaco: Una perspectiva multidisciplinaria]

Atrial isomerism describes complex anatomical findings with defects in the determination of lateralization; being a rare situation, with a prevalence of 1 in every 10.000 to 20.000 live births, with an incidence of up to 4% of all cardiac malformations. The diagnosis can be made in the neonatal age; however, clinical presentation is nonspecific. Depending on the spectrum of malformations, complex and invasive diagnostic tools may be required. Treatment is varied and can range from palliative surgery in view of univentricular physiology to total correction surgery for biventricular repair.

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 Chávez, 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.