Progression of aortic root dilatation and aortic valve regurgitation after the arterial switch operation

Abstract

ObjectiveTo study neo-aortic growth and the evolution of neo-aortic valve regurgitation (AR) in patients with transposition of the great arteries (TGA) after arterial switch operation (ASO) from newborn to adulthood and to identify patients at risk.MethodsNeo-aortic dimensions (annulus/root/sinotubular junction) and neo-aortic valve regurgitation were assessed serially in 345 patients with TGA who underwent ASO between 1977 and 2015. Linear mixed-effect models were used to assess increase of neo-aortic dimensions over time and to identify risk factors for dilatation. Risk factor analysis for AR by using time-dependent Cox regression models.ResultsAfter a rapid increase in the first year after ASO and proportional growth in childhood, neo-aortic dimensions continue to increase in adulthood without stabilisation. Annual diameter increase in adulthood was 0.39±0.06, 0.63±0.09 and 0.54±0.11 mm for, respectively, neo-aortic annulus, root and sinotubular junction, all significantly exceeding normal growth. AR continues to develop over time: freedom from AR ≥moderate during the first 25 years post-ASO was 69%. Risk factors for root dilatation were complex TGA anatomy (TGA-ventricular septal defect (VSD), double outlet right ventricle with subpulmonary VSD) and male gender. Risk factors for AR ≥moderate were: complex TGA anatomy and neo-aortic growth. Per millimetre increase in aortic root dimension, there was a 9% increase in the hazard of AR ≥moderate. Bicuspid pulmonary valve did not relate to the presence of root dilatation or AR.ConclusionAfter ASO, neo-aortic dilatation proceeds beyond childhood and is associated with an increase in AR incidence over time. Careful follow-up of the neo-aortic valve and root function is mandatory, especially in males and in patients with complex TGA anatomy.

Altered Ascending Aorta Hemodynamics in Patients After Arterial Switch Operation for Transposition of the Great Arteries

“…21,22 Neo-aortic root dilatation is a key problem in long-term follow-up in patients after ASO for TGA because of its ongoing progression beyond the age of 18 years. 2,3,23 The neo-aortic root after ASO dilates and elongates and the STJ becomes more distally-displaced over time. 24 Similar to previous findings, 2,5 the geometric alterations in the proximal ascending aorta with neo-aortic root dilatation were accompanied by the relatively narrow mid-ascending aortic segments in this study, due to the anterior impression of the ascending aorta by the pulmonary trunk following the Lecompte maneuver.…”

“…valve reoperation. 2,3 Factors involved in the pathophysiological mechanisms for neo-aortic root dilatation are largely unknown.…”

Imaging large arteries after arterial switch operation

“…A pulmonary artery aneurysm of the pericardial patch is a very rare complication after ASO,1 2 in contrast to a more frequently appearing dilatated neoaortic root 3. Aneurysms of the neoaorta4 or of the ventricular septum5 can appear early post-ASO but would be related to those structures on the images.…”

Transposition of the great arteries: Fetal pulmonary valve growth and postoperative neo‐aortic root dilatation

“…The growth of the anastomoses of the great arteries and the competence of the native pulmonary valve (PV) and root, now functioning as the neo-aortic valve and root (NAoR), in the systemic circulation are important in the long term. [6][7][8] NAoR dilatation has been reported, [8][9][10][11][12][13][14][15][16][17] even in the first year post-ASO, [9][10][11] and the root continues to grow excessively, [15][16][17] at a rate >4 times normal. 9 The resulting aortic valve (AoV) regurgitation and aneurysm formation may require a reintervention.…”

“…Prior pulmonary artery banding, presence of a ventricular septal defect (VSD), TBA, gender, the technique used for the transfer of the coronary buttons, and the length of follow-up have been implicated. [11][12][13][14][15][16][17][18][19][20] The study aim was to document the natural growth of the semilunar valves in fetuses with TGA and to compare it with normal semilunar valve growth. We also wished to determine if NAoR dilatation post-ASO is related to the prenatal semilunar valve growth.…”