Left Ventricular Dysfunction in Neonatal Ebstein's Anomaly and Tricuspid Valve Dysplasia

Background: The mechanisms and prognostic importance of left ventricular (LV) dysfunction in neonatal Ebstein's anomaly (EA) and tricuspid valve dysplasia (TVD) are not well understood. The authors recently demonstrated reduced cardiac output and dyssynchrony to be common in fetal EA/TVD and therefore hypothesized that LV dysfunction may be associated with worse outcomes in neonatal EA/TVD.

Methods: A multicenter retrospective case-control study was conducted among neonatal patients with EA/TVD (n = 32) and a healthy control cohort (n = 17) encountered from 2004 to 2019. The left ventricle was assessed in the first 48 hours after birth using two-dimensional, Doppler-derived, six-segment global and segmental longitudinal strain and circumferential strain (CS) and dyssynchrony indices (the SD of time-to-peak strain and a novel global dyssynchrony index [DI], calculated as [peak segmental average - peak global average]/peak segmental average).

Results: Neonates with EA/TVD demonstrated reduced combined cardiac index (4.2 ± 1.5 L/min/m² vs 6.5 ± 2.2 L/min/m² in control subjects, P < .001), impaired LV CS (-15.4 ± 6.9 vs -26.2 ± 5.8, P < .001), and increased circumferential dyssynchrony (CS DI 0.20 ± 0.16 vs 0.09 ± 0.04 [P = .019]; SD of time-to-peak CS 63 ± 25 vs 40 ± 15 [P = .003]). Transplantation-free survival occurred in 20 of 32 patients (63%) at 6 months. Increased CS DI and absence of pulmonary valve flow (PVF) were most predictive of mortality; CS DI > 0.2 was associated with 25% survival in subjects without PVF, whereas all patients with CS DI < 0.1 survived.

Conclusions: In neonates with EA/TVD and absence of PVF, there is abnormal LV deformation and compromised cardiac output in association with increased dyssynchrony. Increased CS DI is associated with increased risk for mortality in EA/TVD with no forward PVF.