posted on 2018-03-28, 19:07authored byNitin Gupta, Vijaykumar Raju
<p>This patient was a 7-year-old
female child evaluated for cyanosis and failure to thrive since birth. She had
an arterial saturation of approximately 70% on room air. She was diagnosed with
dextro-transposition of the great arteries (D-TGA) with a large subaortic ventricular
septal defect (VSD) and severe pulmonary valve stenosis (PS). Her ventricles
were both good-sized with normal pulmonary artery branch anatomy. She was
referred to the authors for surgical repair.</p>
<p>The pericardium
was harvested and treated with 0.6 % gluteraldehyde for 15 minutes. The aorta, the
main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary
artery (LPA) were dissected. The coronary anatomy was noted. The pulmonary root
was dissected from the aortic root after taking care of the coronary arteries.
Both pulmonary artery branches were dissected up to the hilum on either side.
Cardiopulmonary bypass (CPB) was established with aortic, high superior vena
cava and inferior vena cava cannulation. The left ventricle (LV) was vented
through the right superior pulmonary vein. The patient was cooled to 28 degrees
Celsius. The RPA and LPA were completely dissected up to the hilar branches.
Further dissection of the pulmonary root from the aortic root was carried out. The
aorta was cross-clamped, and the heart was arrested with del Nido cardioplegia
solution. A right ventriculotomy was made well below the aortic valve and
extended to just below the aortic valve. Conal muscle bundles were excised in
the right ventricular outflow tract (RVOT). Routability of VSD to Aorta was
confirmed. The pulmonary root was then harvested entirely from the LV without
damaging the coronary artery, aortic valve, or mitral valve. The large subaortic
VSD was routed in to the aortic valve using a large pericardial patch and a 6-0
proline suture. The routing of the VSD in to the aorta was made possible by a combined
right atrium and right ventricle (RV) approach. The opening in the LV was closed
with an additional pericardial patch. The harvested pulmonary valve opening did
not admit more than a 10 size Hegar dilator. The applicable Z score was 1.6 mm
(1.4 - 2.1), hence the authors decided to cut across the pulmonary valve
annulus. The pulmonary root and pulmonary arteries were moved to the RVOT
without any difficulty. The authors did not divide the aorta nor did they
perform a LeCompte maneuver to bring the entire pulmonary root, the pulmonary
artery, and its branches to the RVOT incision. As mentioned by Da Silva (1), the
technique of pulmonary root translocation keeps the aorta untouched in its
original anterior position, without any coronary artery manipulation. Thus,
postoperative aortic valve dysfunction or coronary artery distortion is not
expected after pulmonary root translocation .</p>
<p>The continuity
between the pulmonary root and the RVOT was established directly in the
posterior layer using a 6-0 proline suture. A large pericardial patch was used
anteriorly, extending from the RVOT to the proximal MPA across the annulus. The
PFO was left behind. After deairing, the cross-clamp was released and the heart
picked up immediately. The patient came off CPB with minimal inotropic support.
Direct needle pressure measurement showed an RV/LV pressure ratio of 0.7. TEE
ruled out new onset aortic or mitral regurgitation. The child had an uneventful
postoperative period and was sent home on the eighth postoperative day. The
patient had uneventful recovery and is doing well at the end of two months
follow up (NYHA class1). There was a mild gradient across the newly constructed
RVOT (25 mm peak gradient), which was noted in her recent echocardiogram. </p>
<p><b>Reference</b></p>
<p>1. da Silva JP, Baumgratz
JF, da Fonseca L. Pulmonary root translocation in transposition of great
arteries repair. <i><a href="https://www.ncbi.nlm.nih.gov/pubmed/10735726">Ann Thorac Surg. 2000;69(2):643-645</a></i>.</p>