Angiotomografia computadorizada na avaliação tardia de pacientes pediátricos submetidos a correção cirúrgica de coarctação de aorta

Abstract

Coarctation of the aorta (CoAo) is a congenital anomaly defined as a spectrum of segmental constrictions of the aorta. It manifests itself since a focal narrowing near the closure site of the arterial ligament adjacent to the left subclavian artery up to a long hypoplastic aortic segment. Transthoracic echocardiography is the first imaging test to be performed, although with some limitations because of possible bone deformities or dificulties in the assessment of extracardiac structures and collateral circulation. Computerized Angiotomography (CAT) provides several advantages such as high special resolution, rapid imaging acquisition, and it is not contraindicated in patients with implants and prostheses. In addition, it is less claustrophobic as compared to Nuclear Magnetic Resonance (NMR) imaging, among others. Objectives – To evaluate the anatomy of pre and post-surgical aorta by CAT in pediatric patients submitted to CoAo correction within one year after the surgical procedure, and its association with other cardiovascular disease, in order to identify predisposing factors for aortic recoarctation. Casuistics and Methods – Twenty-five patients with CoAo diagnosis were studied; they were divided according to sex, age (<15 days of life and ≥15 days) and weight (<2.5kg and ≥2.5kg), considering the groups with and without aortic recoarctation. They were evaluated according to vascular characteristics by CAT examination, as well as pathological conditions. Significance level was set at P-value <0.05. Results – There was similarity between the groups with (N = 8; 32%) and without recoarctation (N = 17; 68%) for sex (male: 87.5% and 53%), age (≥15 days: 62.5% and 82%) and weight (≥2.5kg: 87.5% and 76.5%) (P> 0.05). In preoperative CAT, altered values of aortic root/Valsalva diameter and proximal and distal isthmus (84%, 64%, 100%, respectively) prevailed; and normal values for ascending (92%) and descending aorta (72%). Normal values for aortic root/Valsalva sinus diameter were observed either in patients with (62.5%) and without recoarctation (86.7%, P = 0.283); the same for both groups in relation to ascending aorta 87.5%, 93.7%, P = 1,000), and descending (62.5%, 76.5%, P = 0.639). For the aortic arch, altered values of proximal isthmus were mainly observed in the group without recoarctation (70.5%) versus recoarctation (25%), although without significant difference (P = 0.080), while alterations in distal isthmus were highlighted in both groups (100% and 76.4%, respectively, P = 0.268). Prevailed other cardiovascular anomalies in patients without recoarctation (82.4%), compared to those with recoarctation (12.5%; P = 0.001). Patent ductus arteriosus was stood out in both groups (75%, 82.4%, respectively, P = 0.641). Bone deformities were not detected, and genetic syndromes were observed only in the group without recoarctation (17.6%; P = 0.527). There was no significant difference according to vascular characteristics and pathological conditions in the identification of independent variables for recoarctation (P> 0.05).