Partial anomalous pulmonary venous return in adults. Insight into pulmonary hypertension

Partial anomalous pulmonary venous return (PAPVR) is a rare congenital heart disease (CHD) where pulmonary veins drain into pulmonary circulation leading to a left-to-right shunt. PAPVR can lead to serious consequences, ie pulmonary hypertension (PH). To date, predictors of PH are not well established. The aims of this study were (1) to determine the prevalence of PAPVR (2) to identify the impact of PAPVR on the right ventricle, (3) to determine the prevalence of PH in the PAPVR population and to identify its predictive factors. Patients aged ≥18 years with a non-operated PAPVR and patients operated after the age of 18 were enrolled. Patients with other potential causes of PH were excluded. PH was defined based on right heart catheterization (RHC). For patients without RHC, PH was considered when echocardiographic systolic transtricuspid peak velocity was ≥ 3.4 m/s. Fifty patients were included. Mean patient age was 50 ± 18 years with a 60% female predominance. PAPVR was mostly arising from the right lung (76% of cases) and was associated with CHD in 18 patients (36%). Most of them (83%) were sinus venosus atrial septal defect (ASD). PAPVR was diagnosed by chest computed tomography (CT) in 37 patients (74%). The reported prevalence of PAPVR was 0.2% (23/13606 chest CT reports). PH was identified in 7 patients of the cohort (14%) and 2 of them had Eisenmenger syndrome. All the echocardiographic parameters of RV dimensions were increased. PH group compared to group without PH had a decreased RV FAC (35 ± 13% vs 43 ± 10%, P = 0.049), a decreased RV endoGLS (−18 ± 5% vs −23 ± 4%, P = 0.01) and a significantly higher Qp/Qs ratio (2.2 [1.5;3.0] vs 1.1 [1.0;1.4], P = 0.013). Qp/Qs ratio was the only significant predictive factor for PH (OR = 4.87; P = 0.025), with an AUC of 0.87 (P = 0.016) and the optimal threshold value was 1.95. Prevalence of PAPVR is 0.2% based on chest CT database. 14% of the patients with PAPVR developed PH and 30% of them had Einsenmenger syndrome. RV function parameters (FAC and endoGLS) were significantly decreased in PH group. Qp/Qs was the only significant predictive factor for PH.