10.25373/ctsnet.7051832
Masaaki Yamagishi
Masaaki
Yamagishi
Half-Turned Truncal Switch Operation for Transposition of the Great Arteries With Left Ventricular Outflow Obstruction
CTSNet
2018
Cardiac
Congenital
Cyanotic
Surgery
2018-09-10 17:52:56
Media
https://ctsnet.figshare.com/articles/media/Half-Turned_Truncal_Switch_Operation_for_Transposition_of_the_Great_Arteries_With_Left_Ventricular_Outflow_Obstruction/7051832
<p>The half-turned truncal switch operation is suitable for transposition
of the great arteries (TGA) or TGA-type double outlet right ventricle (DORV)
with left ventricular outflow obstruction, anteroposterior relationship of the
great arteries, and mild-to-moderate pulmonary stenosis. A pulmonary-aortic
annular diameter ratio of 0.3 to 0.8 is most preferable. This operation, which
is not affected by the size or location of the ventricular septal defect (VSD), may
also be indicated for patients with a remote or small VSD. Both wide and
straight ventricular outflow tracts can be reconstructed by the half-turned
truncal switch operation. First, both great arteries are divided and both
coronary arterial buttons are resected. The truncal block, including both
semilunar valves, is resected. The truncal block is half-turned horizontally, so
that the aortic valve is located on the left ventricular
opening. Both coronary cuffs face the opposite aortic wall defects after
half-turning.
After the pulmonary bifurcation is translocated anteriorly, the aortic
valve is anastomosed to the left ventricular opening and both coronary cuffs
are anastomosed.
The right ventricular outflow tract is augmented by commissurotomy or an
expanded polytetrafluoroethylene monocuspid patch. </p>
<p>This video demonstrates the author’s approach for this
procedure. The patient’s pulmonary leaflets were thick and the pulmonary annular
diameter was only 60% of the normal aortic annular diameter (under -2.0 SD).
Moreover, subvalvular muscular stenosis was also present. The pressure gradient
between the left ventricle and pulmonary artery was 64 mm Hg. Therefore, the
surgical team chose the half-turned truncal switch operation instead of an arterial
switch operation with VSD closure. The half-turned truncal switch operation can
be indicated for patients with mild to moderate pulmonary stenosis, in which
the pulmonary-aortic annular diameter ratio ranges from 0.3 to 0.8; this
patient’s ratio was 0.49.</p>
<p>The aorta was transected about 5 mm above the coronary
orifices. The pulmonary artery was also divided horizontally just before the
bifurcation. The anterior wall of the right ventricular outflow tract beneath
the aortic annulus was incised horizontally. The incision line was placed a few
mm away from the aortic annulus. The infundibular septum was incised
transversely. In cases where the VSD is located at a subarterial position, the
incision line may extend to the VSD edge. The midline of the mitral-pulmonary
fibrous continuity was incised. The truncal block, including both semilunar
valves, was resected. The truncal block was half-turned horizontally, so that
the aortic valve was located on the left ventricular opening. The width of the
superior margin of the Gore-Tex® patch was adjusted to the
required length for aortic annular augmentation.</p>
<p>The position of the truncal block should be carefully
adjusted so that the coronary cuff faces the opposite aortic wall defect.
In order to prevent coronary distortion, the aortic valve should be
anastomosed at a slightly higher position around the left coronary artery.
On the posterior aspect, the aortic valve was anastomosed to the mitral
annulus. The superior margin of the Gore-Tex® patch was trimmed, and the
stump of the infundibular septum was anastomosed to the superior margin of the
Gore-Tex®
patch. The crescent-shaped aortic wall patch was anastomosed to the inferoanterior
aspect of the left-sided aortic wall defect. A supplement to the right-sided
aortic wall defect was unnecessary. Neither coronary artery was bent or
stretched. After anterior translocation of the pulmonary bifurcation, the
posteriorly translocated ascending aorta was reconstructed. The pulmonary valve
was anastomosed to the right ventricular outflow tract. The anteriorly
translocated pulmonary bifurcation was anastomosed to the distal stump of the
pulmonary trunk without any supplementary material.</p>
<p>Nonturbulent blood flow and very low energy loss were
verified by fluid dynamic analysis after the half-turned truncal switch
operation and are compared to fluid dynamics after a Rastelli operation. High
wall shear stress by turbulent blood flow may cause intimal damage and
subsequent stenotic lesion. Nonturbulent blood flow and low energy loss were
also verified at the right ventricular outflow tract. Although the half-turned
truncal switch operation is a more invasive surgical procedure, ideal
configuration and hemodynamics can be established by maximal use of
autologous tissue.</p>
<p><b>Suggested Reading</b></p>
<p>Nikaidoh H. Aortic translocation and biventricular outflow
tract reconstruction. A new surgical repair for transposition of the great
arteries associated with ventricular septal defect and pulmonary stenosis. <i><a href="https://www.ncbi.nlm.nih.gov/pubmed/6471887">J Thorac Cardiovasc Surg. 1984;88(3):365-372</a></i>.<br>
<br>
Yamagishi M, Shuntoh K, Matsushita T, et al. Half-turned truncal switch
operation for complete transposition of the great arteries with ventricular
septal defect and pulmonary stenosis. <i><a href="https://doi.org/10.1067/mtc.2003.33">J Thorac Cardiovasc Surg. 2003;125(4):966-968</a></i>.<br>
<br>
Morell VO, Jacobs JP, Quintessenza JA. Aortic translocation in the management
of transposition of the great arteries with ventricular septal defect and
pulmonary stenosis: results and follow-up. <i><a href="https://doi.org/10.1016/j.athoracsur.2004.11.059">Ann Thorac Surg. 2005;79(6):2089-2093</a></i>.<br>
<br>
Yeh T Jr, Ramaciotti C, Leonard SR, Roy L, Nikaidoh H. The aortic translocation
(Nikaidoh) procedure: midterm results superior to the Rastelli procedure. <i><a href="https://doi.org/10.1016/j.jtcvs.2006.10.016">J Thorac Cardiovasc Surg. 2007;133(2):461-469</a></i>.<br>
<br>
Mair R, Sames-Dolzer E, Innerhuber M, Tulzer A, Grohmann E, Tulzer G. Anatomic
repair of complex transposition with en bloc rotation of the truncus arteriosus:
10-year experience. <i><a href="https://doi.org/10.1093/ejcts/ezv056">Eur J Cardiothorac Surg. 2016;49(1):176-182</a></i>.<br>
<br>
Lee JU, Jang WS, Lee YO, Cho JY. Long-term follow-up of the half-turned truncal
switch operation for transposition of the great arteries with ventricular septal
defect and pulmonary stenosis. <i><a href="https://doi.org/10.5090/kjtcs.2016.49.2.112">Korean J Thorac Cardiovasc
Surg. 2016;49(2):112-114</a></i>.<br>
<br>
Nomura K, Yamagishi M, Yamamoto Y, Ko Y. Half-turned truncal switch operation
for single coronary in a patient with transposition of the great artery and
pulmonary stenosis. <i><a href="https://doi.org/10.1016/j.jtcvs.2017.01.048">J Thorac Cardiovasc Surg. 2017;154(1):268-270</a></i>. </p>