Association between hepatic vein Doppler and echocardiographic diastolic indices with invasively measured right ventricular filling pressures in pediatric pulmonary arterial hypertension

BACKGROUND Increased right ventricular filling pressures (RVFP) are associated with increased mortality risk in children with pulmonary arterial hypertension (PAH). We aimed to investigate the correlation of echocardiographic diastolic parameters with invasive measurements of RVFP in pediatric PAH. METHODS We retrospectively reviewed 95 patients and 48 controls from the Hospital for Sick Children in Toronto and Children's Hospital Colorado. RV filling pressures (RVFP) were considered elevated when RV end-diastolic pressures (RVEDP) ≥8 mmHg or mean right atrial pressure (mRAP) >8 mmHg from the catheter. Echocardiographic measurements included hepatic vein A-wave reversal (HVA) velocity and duration, the ratio between HVA and HV systolic velocity (HV A/S), indexed right atrial volume (RAVi), and RV and RA diastolic strains. Logistic regression and receiver operating characteristic curve analysis were used to investigate the predictive value of echo parameters for elevated RVFP. RESULTS PAH patients had significantly elevated HVA velocity, duration and HV A/S, enlarged RAVi, and decreased RA and RV strains. HVA velocity had the highest area under the receiver operating characteristic curve (AUC) for diagnosing elevated RVFP [AUC = 0.788 (0.570-1), p = 0.021]. The model with HVA velocity significantly predicted elevated RVFP [Nagelkerke R2 = 0.339, B(SE) = 0.121 (0.06), odds ratio = 1.129 (1.003-1.27), p = 0.044)]. CONCLUSIONS Of the echo parameters studied, HVA velocity was the best predictor of elevated RVFP in pediatric PAH. But in general, echocardiographic parameters were inadequate indicators of RVFP. Further prospective studies in a larger cohort are needed to determine the association between HV Doppler and changes in RVFP, and ultimately with clinical outcomes.