Incidence and predictors of in-stent restenosis following intervention for pulmonary vein stenosis due to fibrosing mediastinitis.

Background: Fibrosing mediastinitis (FM) is a rare yet fatal condition, caused by different triggers and frequently culminating in the obstruction of the pulmonary vasculature and airways, often leading to pulmonary hypertension and right heart failure. Percutaneous transluminal pulmonary venoplasty (PTPV) is an emerging treatment for pulmonary vein stenosis (PVS) caused by FM. Our previous study showed as high as 24% of in-stent restenosis (ISR) in FM. However, the predictors of ISR are elusive.

Objectives: 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-up, respectively.

Conclusion: ISR is very high in PVS-FM, which is independently associated with RVD and Cor-PA stenosis.

Trail registration: Chinese Clinical Trials Register; No.: ChiCTR2000033153. URL: http://www.chictr.org.cn .