Objective: To define the risk of sudden death in patients with right isomerism (asplenia) after palliation.
Study design: A total of 154 patients with right isomerism was identified from 1980 to 1999. Sudden death was defined as acute cardiovascular collapse from which death occurred within 24 hours.
Results: A total of 620 patient-years were evaluated. The 1-year and 5-year survival was 72% and 50%, respectively. There were 22 sudden unexpected deaths (14%, 35 events/1000 patient-years). Sudden death tended to occur in infancy or early childhood (12 +/- 9 months; median, 9 months). The mechanisms were classified as sudden tachyarrhythmic in 2 (9%), sudden cardiac but nontachyarrrhythmic (sudden onset severe cyanosis) in 15 (68%), and sudden noncardiac in 5 (23%)(fulminant sepsis with positive blood culture: streptococcus pneumonia (3), Escherichia coli (1), and yeast-like organism (1)). The incidence of sudden death steadily decreased with age until the age of 3 years.
Conclusion: The incidence of sudden death in patients with right isomerism after initial palliation remained high. Sudden death was related to complex cardiac anomalies, a susceptibility to fulminant infection, and arrhythmia.