BACKGROUND: The 1.5 ventricle repair is a palliative procedure for patients with congenital heart disease with advanced right heart failure. There are limited data about patient selection and outcomes of this procedure. The purpose of this study was to describe the clinical and hemodynamic characteristics, and outcomes of adults with congenital heart disease (CHD) and 1.5 ventricle repair. METHOD: We studied adults with CHD that underwent 1.5 ventricle repair and received care at Mayo Clinic between January 1, 2003, and December 31, 2023. The patients were divided into two cohorts. Cohort #1 comprised of patients that had 1.5 ventricle repair prior to adulthood (age <
18 years), while Cohort #2 comprised of patients that underwent 1.5 ventricle repair in adulthood (age ≥18 years). RESULTS: There were 61 patients with 1.5 ventricle repair (Cohort #1 n=39, 64%
Cohort #2 n=22, 36%). In Cohort #1, the median age at the time of 1.5 ventricle repair was 7 years (interquartile range [IQR]: 1-12), while the median age at presentation to the CHD clinic was 20 years (IQR: 18-27). Of the 39 patients in Cohort #1, 4 (10%) required reintervention. The 10-year risk of death/transplant was 14%. In Cohort #2, the median age at the time of 1.5 ventricle repair was 33 years (IQR: 23-44), and the operative mortality was 4%. There was an improvement in cardiac output, functional status, and reduction in the proportion of patients with stage D heart failure at 1 year after 1.5 ventricle repair. CONCLUSIONS: The 1.5 ventricle repair is a viable treatment option in patients with advanced heart failure and may delay the need for heart transplant.