请帮我检查下文语法：Objective With the improvement of surgical procedures and perioperative management the postoperative mortality of patients with aortic coarctation has been reduced but the postoperative re-c

Objective: With the improvement of surgical procedures and perioperative management, the postoperative mortality of patients with aortic coarctation has been reduced. However, the postoperative re-coarctation rate remains high, and it seriously affects the quality of life of patients, making it an important index to evaluate the efficacy of surgery. Despite differences in the morphological characteristics of the aortic arch in patients with aortic coarctation, the effect of preoperative aortic morphology on postoperative re-coarctation is still uncertain. Additionally, there are limited reports on the effect of reintervention on postoperative re-coarctation. The purpose of this study is to summarize the anatomical characteristics of the patients, explore the risk factors of postoperative re-coarctation combined with clinical data, and analyze the mid-term effect of reintervention.

Methods: We retrospectively reviewed patients with aortic coarctation who underwent surgical treatment in our hospital from January 2016 to January 2020. We collected demographic data, surgical data, echocardiography, cardiac CTA, and other imaging data of the patients. We also reviewed patients with aortic coarctation who underwent reintervention in our hospital from January 2012 to December 2022. We compared the changes of pressure gradient at the coarctation site before and after operation to determine the occurrence of postoperative re-coarctation.

Results: A total of 148 patients were included, with 40 cases (27.0%) of Gothic style, 77 cases (52.3%) of Roman style, and 31 cases (20.9%) of wall style. There were 51 patients (34.5%) with hypoplastic aortic arch. The median age was 2.1 (0.9,5.2) months, and the median weight was 4 (3.2,5.8) Kg. Four early deaths occurred, and there were no late deaths. Late re-coarctation occurred in 17 patients. The 5-year survival rate was 96.8%, and the 5-year freedom from re-coarctation rate was 68.5%. The risk factors for re-coarctation were walled aortic arch (HR=8.327, 95% CI: 2.329-29.773, P=0.001) and age at surgery (HR=1.025, 95% CI: 2.329-29.773, P=0.001). The lateral thoracotomy approach was also a risk factor (HR=5.002, 95% confidence interval: 1.684-14.854, P=0.004). In the past 11 years, 13 patients underwent reintervention due to re-coarctation, with 8 patients undergoing surgical repair, 4 patients undergoing medical balloon dilatation, and 1 patient undergoing medical stent implantation. After the second intervention, the pressure gradient at the re-constriction site decreased in all patients. The overall average peak pressure gradient at the constriction site decreased from 55.50±24.25 mmHg to 20.10±11.81 mmHg (p < 0.001). During the follow-up period, no patient died, and 3 patients had secondary coarctation after operation.

Conclusions: Roman type is the most common form of aortic arch in children with aortic constriction. Postoperative follow-up should be strengthened for patients with wallstack aortic arch, older than 1 year old, and lateral thoracotomy. Timely intervention of postoperative re-coarctation is effective and safe.

Key words: aortic coarctation; re-constriction; surgical treatment; congenital heart disease