Staged Left Ventricular Recruitment After Single-Ventricle Palliation in Patients With Borderline Left Heart Hypoplasia

OBJECTIVES The goal of this study was to review results of a novel management strategy intended to rehabilitate the left heart (LH) in patients with LH hypoplasia who have undergone single-ventricle palliation (SVP). BACKGROUND Management of patients with hypoplastic LH syndrome and borderline left ventricle (LV) involves 2 options: SVP or biventricular repair. We hypothesized that staged LV recruitment and biventricular conversion may be achieved after SVP by using a strategy consisting of relief of inflow and outflow tract obstructions, resection of endocardial fibroelastosis, and promotion of flow through the LV. METHODS Patients with hypoplastic LH and borderline LV who underwent traditional SVP (n = 34) or staged LV recruitment (n = 34) between 1995 and 2010 were retrospectively analyzed and compared with a control SVP group. RESULTS Mean initial z-scores for LH structures before stage 1 SVP were not significantly different between groups. Mortality occurred in 4 of 34 patients after LV recruitment and in 7 of 34 after traditional SVP. LH dimension z-scores increased significantly over time after LV recruitment, whereas they declined after traditional SVP, with significant interaction between stage of palliation and treatment group. Restriction of the atrial septum (conducted in 19 of 34 patients) was the only predictor of increase in left ventricular end-diastolic volume (p < 0.001). Native biventricular circulation was achieved in 12 patients after staged LV recruitment; all of these patients had restriction at the atrial septum. CONCLUSIONS In these patients with borderline LH disease who underwent SVP, it is possible to increase LH dimensions by using an LV recruitment strategy. In a subset of patients, this strategy allowed establishment of biventricular circulation.