Discussion
In recent studies, planning a PVR for repaired TOF patient has focused at the timing, considering irreversible dysfunction of the RV and repeated intervention.1 These studies aimed at several factors including RV volume status, exercise function, arrhythmia, and tricuspid regurgitation etc., however, standard indication is still not established.1,2 In addition, a range of surgical suggestions with a broad spectrum of patient status including other cardiac lesions which causes significant hemodynamics are making surgeons decision more complicated. Our case was an extreme rare case that a repaired TOF patient was developing PR accelerated by a mixed type PAPVR.
TOF with anomalous pulmonary venous connection is extremely rare (0.6% of TOF patients) and there are only few reports in the English medical literature.3 This case, moreover, is unique according to a mixed type PAPVR pattern which RUMPVs, LUPV, and LLPV were connected to right SVC, left SVC, and LHV. Redington et al. reported four (0.3%) of PAPVR patients among 1183 TOF patients which only corrected the TOF lesion without rerouting the anomalous pulmonary vein (one or two lobar vessels) during the 17 years of follow up period.3 In this case, however, rerouting was performed because the four out of five lobar pulmonary veins were connected to systemic veins and significant volume overload was identified. In LLPV rerouting, baffling and internal closure technique was used instead of direct implantation to the left atrium since the LLPV had an intra-pulmonary course toward the subdiaphragmatic area and the venous plexus between the LHV and MHV had a sufficient flow. Internal closure technique was used to separate the hepatic venous flow and a baffle was placed within the lumen of IVC which is a similar fashion with correcting in ‘Scimitar syndrome’ with a long baffle.6 Hepatic collaterals had developed well assuming the pressure gradient between the LHV and MHV, which the precise mechanism is still unclear.7,8
Innominate vein is a well-known site for anomalous connection of left pulmonary veins, however, there have been rare reports which left pulmonary veins connected to IVC.4,5 To our knowledge, this might be the first reported instance of a unique pattern of PAPVR which anomalous pulmonary drains were connected to the right SVC, left SVC, and LHV.