Abstract
A boy with asplenia syndrome and functional single ventricle experienced complications of right hemidiaphragmatic paralysis when undergoing the bidirectional Glenn procedure at 10 months of age. Cardiac catheterization revealed steal phenomenon of the upper systemic blood flow through the hemiazygos vein to the lower. After diaphragm plication at 1 year and 11 months of age, pulmonary hemodynamics was reassessed under balloon occlusion of the hemiazygos vein. Right, left, and total pulmonary vascular resistance was 7.84, 3.89, and 2.60 Wood units・m2, respectively. Though imbalanced in the laterality of pulmonary circulation, the Fontan procedure was considered as applicable to the patient. Total cavopulmonary connection (TCPC) and replication of the diaphragm were performed at 2 years and 10 months of age. Cardiac catheterization 7 months after the operation showed low mean pulmonary pressure (11 mmHg), low total pulmonary vascular resistance (2.04 Wood units・m2), and high enough cardiac index (3.64 L/min/m2), and the patient seemed to have a good Fontan physiology from the uneventful postoperative clinical course. The laterality of pulmonary circulation, however, remained imbalanced (right and left pulmonary resistance was 5.69 and 3.20 Wood units・m2, respectively). Diaphragmatic paralysis is a risk factor to deteriorate Fontan circulation because diaphragmatic function is very important in Fontan physiology, which lacks the ventricular driving force for pulmonary blood flow. This case presented an imbalance in the laterality of pulmonary circulation that existed even after diaphragm plication, which suggested the need for further careful follow-up for the so-called failing Fontan physiology.
