ABC | Volume 111, Nº1, July 2018

Original Article Martins et al Regurgitation aortic after Jatene Surgery Arq Bras Cardiol. 2018; 111(1):21-28 time Jatene surgery is performed, and presence of VSD and complex TGA, 6,18-21 but such findings could not be repeated in some other large series. 8,23 In our series, as in others, 6,21,23 we observed that the most relevant factor for neo‑aortic regurgitation was the great disproportion in the sizes of the neo-aorta and neo-pulmonary artery at the time of surgery, which was present in the complex TGA group, especially when aortic arch anomalies were associated. In addition, the VSD found in the complex TGA group is related to two factors that increase the risk for developing valvular regurgitation, pulmonary root dilation and pulmonary artery pressure elevation, which can change the arrangement of the muscle fibers and generate permanent disarrangement of the pulmonary artery, even after anatomical correction. 25 The presence of neo-aortic valve regurgitation in patients without risk factors, such as simple TGA, can be explained in histopathological studies revealing a reduction in the amount of collagen in the arterial roots in hearts with TGA as compared to that of normal hearts, in addition to less extensive anchorage and embedding of both arterial roots in the myocardium. 26 The pulmonary root dilation can be compared to that observed after the Norwood surgery for hypoplastic left heart syndrome, 27 indicating the pulmonary artery included in the systemic circulation is a risk factor per se. From the morphological and histological viewpoints, the pulmonary and aortic valves are indistinguishable at birth. In normal hearts, studies have shown gross and microscopic changes in those valves, probably due to pressure changes resulting from the transition from the fetal to post-natal circulation, resulting in pulmonary valve with thin leaflets, less collagen and a smaller amount of elastic tissue. After surgical repair, the more delicate valve is integrated into the systemic circulation and can be damaged by the high-pressure regime. 27 Briefly, the etiology of neo-aortic valve regurgitation and neo‑aorta dilation is very likelymultifactorial. In addition toexternal risk factors, there are intrinsic structural problems of the pulmonary root integrated into the systemic circulation. Thus, according to our clinical observations, the increase in the number of surgical interventions to treat aortic root dilation and neo-aortic valve regurgitation should be the reason for the constant monitoring of patients with or without additional risk factors. The present study, similarly to others, 21-23 showed that the most relevant factor for neo-aortic valve regurgitation was the disproportion in the sizes of the neo-aorta and neo‑pulmonary artery at the time of surgery, which was present in the complex TGA group, especiallywhen associatedwith aortic arch anomalies. Conclusion In the present study, the complex TGA group had a higher preoperative pulmonary artery Z-score as compared to that of the simple TGA group, and a higher incidence of associated anomalies, such as aortic arch anomalies (p = 0.0064). In addition, the neo-aorta dilation is maintained in the postoperative period. Our results showed that the larger the aortic annulus, the higher the regurgitation grade (p < 0.001). In addition, moderate regurgitation was associated with a higher mean age (p = 0.0145) in both simple TGA and complex TGA groups, indicating the need for the constant monitoring of the patients. Limitation The present retrospective study results from the data collection of two groups of patients with distinct anatomical characteristics, submitted to the same surgical technique. Some variations related to the presence of aortic regurgitation in the long run reported by other authors (techniques of coronary reimplantation, VSD closure and previous pulmonary artery cerclage) were not approached in this study. Author contributions Conception and design of the research and Writing of the manuscript: Martins CN, Gontijo Filho B, Lopes RM, Lima e Silva FC; Acquisition of data: Martins CN; Analysis and interpretation of the data: Martins CN, Gontijo Filho B, Lima e Silva FC; Statistical analysis: Martins CN, Lima e Silva FC; Critical revision of the manuscript for intellectual content: Martins CN, Gontijo Filho B, Lima e Silva FC. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This article is part of the thesis of master submitted by Cristiane Nunes Martins, from Instituto de Ensino e Pesquisa (IEP) Santa Casa - MG. Ethics approval and consent to participate This study was approved by the Ethics Committee of the Instituto de Ensino e Pesquisa Santa Casa-BH under the protocol number 7.345. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study. 26