Common atrial reservoir strain during the interstage period is a predictor of poor outcomes prior to Fontan completion in hypoplastic left heart syndrome

Background: The atrium augments ventricular function, but the significance of atrial function in hypoplastic left heart syndrome (HLHS) has not been well evaluated.

Objective: We investigated the association of atrial reservoir strain (common atrial strain [CAS]) to death or need for transplantation in patients with HLHS.

Methods: In this retrospective single-center study, echocardiograms from three timepoints (pre-stage 1 palliation [S1P], 4-8 weeks post-S1P, and pre-Glenn) were analyzed in infants with classic HLHS. Patients were separated based on transplant-free survival to Fontan (survivors) versus death or heart transplant prior to Fontan (composite outcome). Echocardiographic parameters evaluated included CAS, right ventricle (RV) global longitudinal strain (RVGLS), RV fractional area change (FAC), and tricuspid annular plane systolic excursion (TAPSE). An equal variance t-test, regression, and receiver operating characteristic (ROC) analyses were performed.

Results: A total of 45 HLHS patients (25 survivors, 20 patients meeting endpoint) were included in this study. There were no significant differences in any of the functional parameters during the pre-stage 1 or post-stage 1 timepoints. Pre-Glenn CAS and RVGLS were significantly worse in those meeting composite endpoint compared to survivors. CAS was significantly correlated to RVGLS during the pre-S1P and pre-Glenn timepoints. A pre-Glenn CAS < 19.5 had an area under the curve of .78 and a 75% sensitivity and 83% specificity for death or need for transplantation.

Conclusion: Pre-Glenn CAS is significantly lower in patients with mortality or need for the transplantation prior to Fontan completion and may carry prognostic significance in patients with HLHS.