Residual obstruction at the site of pulmonary venous repair is manifested by poor cardiac output and chest radiograph findings of pulmonary congestion. The principle diagnostic feature is the presence of turbulence at the pulmonary venous anastomotic site, as noted on echocardiograph images. Residual turbulence may create a cycle of local injury, hyperplasia, and increasing turbulence, thereby perpetuating a process of diffuse pulmonary vein stenosis. Pulmonary vein stenosis may remain localized to the site of anastomosis, may progress unilaterally with diffuse pulmonary vein stenosis, or may progress with bilateral diffuse pulmonary venous stenosis.

Better neonatal care and surgical techniques have created vast improvements in surgical survival rates in neonates requiring repair of TAPVD. However, in some subsets of patients, risk of surgical death is extremely high. Specifically, patients with single ventricles and TAPVD requiring repair in the neonatal period have a higher rate of surgical mortality, largely because postoperative management of hemodynamics is difficult.

A second frontier in treatment in patients with TAPVD is in patients with postsurgical pulmonary vein obstruction. Improved understanding of the vascular biology responsible for diffuse pulmonary vein stenosis in this group will lead to better therapy. At present, surgical therapy with sutureless techniques and/or transplantation may offer the most potential.