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.