Supracardiac total anomalous pulmonary venous connection type Ib: Morphology and outcomes

Background: Supracardiac total anomalous pulmonary venous connection is the most common subtype of total anomalous pulmonary venous connection. We aimed to describe the morphological spectrum of supracardiac total anomalous pulmonary venous connection and to identify risk factors for death and postoper-ative pulmonary venous obstruction.Methods: From February 2009 to June 2019, 241 patients diagnosed with supracardiac-Ia (left-sided vertical vein, n = 185) or supracardiac-Ib (right-sided connection directly to superior vena cava, n = 56) total anomalous pulmonary venous connection underwent initial surgical repair at our institute. Cases with functionally univentricular circulations or atrial isomerism were excluded. Patients' postoperative survival was described by Kaplan-Meier curves. Cox proportional hazards models and competing risk regression models were used to identify clinical risk factors for death and postoperative pulmonary venous obstruction.Results: There were 8 early deaths and 4 late deaths. The overall survivals at 30 days, 1 year, and 10 years were 97.1%, 94.8%, and 94.8%, respectively, in the supracardiac-Ia group (2.7%, 5/185) (hazard ratio, 4.8; P = .003). Five patients required reoperation for pulmonary venous obstruction, including 2 patients who required reintervention for superior vena cava syndromes (all in the supracardiac-Ib group). One patient required superior vena cava balloon dilation for superior vena cava syndromes. Multivariable analysis showed that the supracardiac-Ib group (12.5%, 7/56) had a significantly higher mortality rate than the supracardiac-Ia group (adjusted hazard ratio, 8.5, P = .008). Surgical weight less than 2.5 kg (adjusted haz-ard ratio, 10.8, P = .023), longer duration of cardiopulmonary bypass (adjusted haz-ard ratio, 1.15 per 10 minutes,P = .012), and supracardiac-Ib subtype (adjusted hazard ratio, 4.7, P = .037) were independent risk factors associated with death. The supracardiac-Ib subtype (adjusted hazard ratio, 4.8, P = .003) was an incremental risk factor associated with postoperative pulmonary venous obstruction.Conclusions: Morphological features of supracardiac total anomalous pulmonary venous connection, especially the supracardiac-Ib subtype, were risk factors associated with postoperative pulmonary venous obstruction and survival. Patients with unique anatomic subtypes might require more individualized surgical planning.