Incidence and Predictors of In-stent Restenosis Following Intervention for Pulmonary Vein Stenosis due to Fibrosing Mediastinitis

Background: Percutaneous transluminal pulmonary venoplasty (PTPV) is an emerging treatment for pulmonary vein stenosis (PVS) caused by fibrosing mediastinitis (FM). However, the incidence and predictors of in-stent restenosis (ISR) are elusive. We sought to identify the predictors of ISR in patients with PVS caused by extraluminal compression due to FM. Methods: We retrospectively enrolled patients with PVS-FM who underwent PTPV between July 1, 2018, and December 31, 2022. According to ISR status, patients were divided into two groups: the ISR group and the non-ISR group. Baseline characteristics (demographics and lesions) and procedure-related information were abstracted from patient records and analyzed. Univariate and multivariate analyses were performed to determine the predictors of ISR. Results: A total of 142 stents were implanted in 134 PVs of 65 patients with PVS-FM. Over a median follow-up of 6.6 (3.4-15.7) months, 61 of 134 PVs suffered from ISR. Multivariate analysis demonstrated a significantly lower risk of ISR in PVs with a larger reference vessel diameter (RVD) (odds ratio (OR): 0.79; 95% confidence interval [CI]: 0.64 to 0.98; P=0.032), and stenosis of the corresponding pulmonary artery (Cor-PA) independently increased the risk of restenosis (OR: 3.41; 95% CI: 1.31 to 8.86; P=0.012). The cumulative ISR was 6.3%, 21.4%, and 39.2% at the 3-, 6-, and 12-month follow-ups, respectively. Conclusion: ISR is very high in PVS-FM, which is independently associated with RVD and Cor-PA stenosis. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial ChiCTR2000033153 ### Funding Statement This work was supported by the National Natural Science Foundation of China (82070052) and the Open Project of State Key Laboratory of Respiratory Disease (SKLRD-OP-202301). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The ethics committee of Gansu Provincial Hospital reviewed and approved the study protocol (2022-302) on 25, August 2022 as well as granted exemption from obtaining informed consent from patients. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Anonymized data used and/or analyzed during the current study are available from the corresponding author upon reasonable request from any qualified investigator for the sole purpose of the study.