Echocardiographic Findings Associated with Transplant-free Survival and Left Ventricular Systolic Function at Mid-term Follow-up after Ross Procedure in Infants with Critical Aortic Stenosis.

BACKGROUND: The Ross operation is an important option for children with critical aortic stenosis (CAS) with residual disease, but operation in infancy is associated with significant morbidity and mortality. We evaluated echocardiographic correlates of transplant-free survival, re-intervention, and left ventricular (LV) function in mid-term follow-up.

METHODS: This retrospective, single-center study included all infants with CAS who underwent Ross by 1 year of age from 1/2000 to 9/2018. Serial echocardiograms were analyzed for LV ejection fraction (EF) and systolic and diastolic longitudinal strain (LS). The primary outcome was mortality or transplant; secondary outcomes were re-intervention and abnormal LVEF (≤55%).

RESULTS: In 40 infants (30 [75%] male; median age at Ross 51 days) with median follow-up 3.3 years (interquartile range 1.0-9.4), the primary outcome was met in 11/40 (28%). Transplant-free survival was 79%, 77%, and 69% at 1, 5, and 10 years post Ross. Predictors of transplant or death included neonatal surgery, cross-clamp time, and pre-operative left atrial dilatation and lower LVEF. Median freedom from re-intervention was at 7.1 years post Ross, with no identified associations. LV LS improved 1 year post-Ross (-21.1±3.8% vs. -17.4±5.1%, p=0.02), although LVEF did not reach significance. Lower LVEF at 1 year was related to pre-Ross LA dilatation (p=0.02), abnormal LVEF (p=0.04), and lower early diastolic LS rate (p=0.03). LVEF remained stable 3-years post Ross.

CONCLUSION: Both transplant-free survival and normalization of LV function post Ross in infancy are associated with pre-operative LV systolic and diastolic measures, highlighting the prognostic value of echocardiography in this population. Further data are necessary in a larger, multicenter cohort, to allow for more precise risk stratification.