2.2 Surgical techniques
The first patient underwent staged repair, with a thoracotomy approach
for coarctation repair without PA banding, followed by the ASO performed
via a median sternotomy approach later. All the remaining TBV patients
in our study, including the patients who required aortic arch
reconstruction as well, were treated via a single incision through a
median sternotomy using isolated cerebral perfusion.
Standard bypass was established with an arterial cannula placed at the
base of the innominate artery, bicaval cannulation and moderate
hypothermia was used for all patients in our study. The autologous
pericardium was harvested and kept in saline. The core temperature was
decreased to 28°C during dissection, and near-infrared spectroscopy was
used to monitor all patients. In cases in which coarctation or aortic
arch reconstruction was required, the aortic cannula was advanced into
the innominate artery, and antegrade cerebral perfusion was performed
with the surgical technique for aortic arch reconstruction, as
previously described (11). The closed technique for coronary transfer
was used in all patients (12). We combined the trapdoor technique for
left coronary button reimplantation and a simple incision for the right
coronary button to minimize dilatation of the sinotubular junction and
the sinus of Valsalva. The Lecompte maneuver was applied in all cases,
irrespective of the relationship of the great arteries. The majority of
patients underwent VSD closure through the right atrium using
interrupted pledget sutures, except for 1 patient, who required an
approach through the neopulmonary valve (neo-PV). For the upper part of
the VSD, as the most difficult part of VSD closure through right atrial,
a needle holder is used to shape the suture needle into a “fishhook”
shape, and a forceps was used to temporary push down the outside of the
pulmonary annulus. The surgeon can now easily see the superior aspect of
the VSD, and close it through the tricuspid valve. The neo-PA was
reconstructed using a fresh autologous pericardial patch, with
particular care taken to trim the height and width of the patch to avoid
torsion of the pulmonary bifurcation, which we considered to be the main
cause of PA branch stenosis after the operation. We took meticulous care
to make sure that the height of the neo-PA patch was equal to the height
of the remaining anterior wall of the neo-PA, the width of the patch was
not excessive and the diameter of the neo-PA after reconstruction was
equal to the diameter of the PA bifurcation.
Before releasing the aortic cross clamp, the RVOT was always examined
through the neo-PV. In cases where SPT were prominent and protruded into
the RVOT, they were excised or divided totally from the RVOT up to the
apex of the right ventricle, if possible, to avoid RVOTO. The key point
to help surgeons realizes these structures and avoid resecting too much
out of the heart is that these structures lie in an abnormal position,
making connections adherent between the posterior ventricular septum at
the infundibulum area superiorly, continuous with the tricuspid annulus
at the area of inlet component of the right ventricle inferiorly, and
the free wall of the right ventricle, which is not seen in the normal
heart (Figure 1). These anomalous structures were described by Dr.
Robert Anderson, which is also described as the right ventricular
trabeculations arise from the anterior margin of the septomarginal
trabeculation (page 41, Anatomy of the cardiac chambers) (13). These
muscle bands are customary to the TBV lesion, are easily identified by
RVOT inspection after ASO + VSD closure. Additionally, when the neo-PV
annulus appeared hypoplastic, an approach through the tricuspid valve
could be used to divide the SPTs.
The patent foramen ovale was stretched or a small atrial septal defect
was left open to help decompress the right ventricle and maintain the
cardiac output of the patient during intensive care management. Distal
anastomosis of the neo-PA was completed after removal of the Ao cross
clamp. In cases where the great arteries were side-by-side or the aorta
arose from the anterior and right sides of the pulmonary system, the
neo-PA was then shifted to the right PA to avoid coronary compression or
torsion of the distal PA. The remaining defect in the PA bifurcation was
closed by an autologous pericardial patch to avoid left PA stenosis.
In patients who required reoperation due to RVOTO, the procedure was
performed through the neo-PA and the tricuspid valve, and the SPT
remnants were resected, with the RV pressure being directly measured in
combination with transesophageal echocardiography to confirm freedom
from RVOTO. No transannular patches were required in our series for
reoperation because we did not identify any cases of significant
hypoplasticity of the neo-PV annulus during follow-up.