Echocardiographic measures of ventricular-vascular interactions in congenital diaphragmatic hernia.

Objective: To evaluate the utility of echocardiographic measures of ventricular-vascular interactions in predicting death or ECMO in congenital diaphragmatic hernia (CDH).

Design: In this single center retrospective study, early (<48 hour age) Doppler ECHOs of neonates (≥34 weeks gestation) with CDH (n = 58) were reviewed. ECHO measures of the relationship of right ventricular (RV) contractility and pulmonary hypertension (PH) were selected: Ratios of 1. pulmonary artery acceleration time to pulmonary ejection time (PAAT/PET) 2. tricuspid annular plane systolic excursion, a measure of regional RV function, to PAAT (TAPSE/PAAT) 3. patent ductus arteriosus (PDA) flow velocity time integral (VTI) from right to left (PDA/RLVTI) 4. PDA flow duration from right to left (PDA/RL) and 5. TAPSE to RV systolic pressure (TAPSE/RVSP). Statistical analyses included t-test and chi-square test and receiver operating characteristic curves were generated.

Results: Our cohort (n = 58) comprised 34 (59%) males and predominantly (81%) left sided CDH. Of these, 34 (58.6%) infants died or received ECMO and 24 (41.4%) survived without ECMO. RVSP and PDA/RL VTI were higher, and RV TAPSE, PAAT/PET, TAPSE/PAAT and TAPSE/RVSP ratios were all significantly lower in the death/ECMO group. PDA/RLVTI ratio had the highest area under the curve (0.76); values ≥ 0.6 had high specificity [88% (95% C.I. 62-98%)] and positive predictive value [88% (95% C.I. 65-96%)] for adverse outcomes.

Conclusion(s): Novel early ECHO parameters which combine RV function and PH severity were found to be feasible and prognostic in CDH. A detailed non-invasive assessment of ventricular-vascular interactions is important for risk-stratification in this population.