Cross sectional imaging is transforming the diagnosis of rare congenital defects

Aim Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital anomaly in which at least one of the pulmonary veins do not drain into the left atrium. Patients with PAPVC can often be asymptomatic and the presence of right heart dilatation on echo should prompt assessment of pulmonary venous anatomy. The aim of this study was to compare the anatomical features of a contemporary cohort of patients with PAPVC with previous historical cohorts, in order to determine whether the use of 3 dimensional imaging techniques has altered the diagnostic yield of PAPVC anatomical subtypes. Methods A retrospective review of patients diagnosed with PAPVC on the basis of CT and/or MRI imaging, between 2010 and 2020. Results 45 cases of PAPVC were found. 60% were women with an average age of 53 years (17–85 years). 25 cases were diagnosed on MRI and 20 on CT, with CT scanning being used with increasing frequency during the period covered. The most common pattern was right-sided involvement, with isolated right PAPVC in 36 patients (80%) – see chart 1. Of these, the majority had isolated right upper PAPVC (19, 53%); 13 (36%) had right upper and middle PAPVC, 1 had isolated right middle PAPVC, 2 had isolated right lower PAPVC, and 1 had unilateral right-sided PAPVC. Bilateral involvement was seen in 4 patients (9%), isolated left-sided involvement in 3 (7%), and right upper and middle and left upper PAPVC in 2 (4%). Associated sinus venosus defects (SVDs) were only detected in 15 cases (33%): 14 had right-sided APVC and 1 had bilateral upper PAPVC. There were 13 superior SVDs, 1 inferior SVD and 1 coronary sinus SVD (see chart 2). 13 of the 27 (48%) women had Turner's Syndrome, Most had right-sided PAPVC (8, 61%), with bilateral involvement in 3 (23%) and left-sided PAPVC in 4 (31%) – see chart 3. 17 (38%) of the patients have had their PAPVC surgically redirected, of which 13 (29%) had an associated SVD. Conclusion With Increasing use of cross sectional imaging, we are seeing anatomical heterogeneity in patterns of PAPVC compared to historical cohorts1,2. Interatrial communications were less frequently seen, with unusual patterns of drainage seen more frequently in our Turner's Syndrome group. Funding Acknowledgement Type of funding sources: None. CT scan of bilateral PAPVC