Management and Outcomes of Right Atrial Isomerism: A 26-Year Experience

Abstract

Objectives. We sought to determine, in a large series of patients with right atrial isomerism, factors associated with mortality.Background. Right atrial isomerism is associated with complex congenital heart disease and high morbidity and mortality.Method. All data from patients diagnosed with right atrial isomerism between January 1970 and March 1996 were reviewed.Results. A total of 91 consecutive patients (54 male) were identified. Most patients (89%) presented within the first month of life, 62% at birth. Cardiac abnormalities included common atrioventricular (AV) valve (81%), ventricular hypoplasia or single ventricle (73%), abnormal ventriculoarterial connections (96%), pulmonary outflow tract obstruction (84%), anomalous pulmonary venous drainage (87%) and pulmonary vein obstruction (30%). The overall mortality rate was 69%. No interventions were planned or performed in 24%, 95% of whom died. The mortality rate for patients requiring their first cardiovascular operation in the neonatal period was 75% versus 51% for those with later first operations (p < 0.05). The surgical mortality rate for patients undergoing pulmonary vein repair was 95%. Overall survival estimates were 71% at 1 month, 49% at 1 year and 35% at 5 years. Independent risk factors for decreased time to death included the absence of pulmonary outflow obstruction (relative risk [RR] 2.23, p < 0.03), presence of major AV valve anomaly (RR 5.23, p < 0.03) and obstructed pulmonary veins (RR 5.43, p < 0.0001).Conclusions. Right atrial isomerism continues to have an associated high mortality despite surgical innovations. Management of pulmonary vein obstruction remains a serious problem and is associated with high mortality.