Impact of left ventricular rehabilitation on surgical outcomes in patients with borderline left heart hypoplasia

Objective: The clinical significance of left ventricular rehabilitation for borderline left ventricular hypoplasia is controversial. This study aimed to review the surgical results of patients with borderline left ventricular hypoplasia and to evaluate the impact of left ventricular rehabilitation on outcomes. Methods: Patients diagnosed with borderline left ventricular hypoplasia and surgically treated from 2018 to 2022 were included. Overall surgical outcomes were evaluated. The changes in left ventricular volumes were calculated using angiography, and age-adjusted z-score N-terminal pro-B-type natriuretic peptide levels were analyzed in patients who underwent left ventricular rehabilitation. Results: Thirty-three patients were included. Sixteen patients underwent primary biventricular repair, 3 patients underwent primary single ventricle palliation, and the remaining 14 patients underwent left ventricular rehabilitation; 9 received bilateral pulmonary artery banding and ductal stenting, 4 received central pulmonary artery banding, and 1 received ductal stenting. Of 14 patients who received left ventricular rehabilitation, 1 died, 1 underwent single ventricle palliation, 1 was waiting for further procedure, and 11 underwent biventricular repair. After biventricular repair, 2 patients died, and 1 patient developed hemodynamic failure. As a result, only 8 patients were alive and in good condition. In patients who underwent left ventricular rehabilitation, left ventricular end-diastolic volume index, end-systolic volume index, and left ventricular stroke volume index increased over time after left ventricular rehabilitation (P = .001, P = .007, and P = .009, respectively). The age-adjusted z-score N-terminal pro-B-type natriuretic peptide levels were stable until biventricular repair, but significantly higher in patients who presented with hemodynamic failure after biventricular repair compared with patients who did not exhibit hemodynamic failure. Conclusions: In patients with borderline left heart hypoplasia, the left ventricular rehabilitation procedure promoted an increase in left ventricular volume and contributed to establishing a biventricular circulation. The short-term results of this strategy are satisfactory, but further studies are essential to determine the long-term outcomes.