Long-term outcomes of stent-based pulmonary angioplasty for isolated peripheral pulmonary artery stenosis

BACKGROUND: Isolated peripheral pulmonary artery stenosis (PPAS) is a rare condition without standardized therapeutic strategies. Short-term clinical benefits of stent implantation have been reported; however, long-term durability and the incidence and determinants of in-stent restenosis (ISR) remain unclear. METHODS: This single-center retrospective study included 23 consecutive adults with isolated PPAS who underwent stent-based angioplasty between 2007 and 2024. Changes in hemodynamics, six-minute walk distance, and long-term survival were assessed. Predictors of ISR were evaluated using Cox proportional hazards models with a patient-level frailty term to account for within-patient clustering. RESULTS: Among 23 patients, 479 stents were implanted. Mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance, and six-minute walk distance significantly improved following stent-based angioplasty. The 3-year cumulative incidence of ISR was 45.8%. Smaller stent diameter (hazard ratio [HR]: 0.582, 95% confidence interval [CI]: 0.381-0.889, P = 0.012), longer stent length (HR: 1.027, 95% CI: 1.005-1.049, P = 0.017), and higher mPAP at stenting (HR: 1.017, 95% CI: 1.000-1.034, P = 0.045) were independently associated with ISR. Among lesions requiring reintervention, the 3-year cumulative incidence of recurrent ISR was 52.0%. Despite frequent ISR, most lesions were successfully retreated, with sustained improvements in hemodynamics and functional capacity. Estimated 5- and 10-year survival rates were 90.4% and 80.4%, respectively. CONCLUSIONS: In isolated PPAS, ISR appears to be common and potentially manageable through structured surveillance and timely reintervention. This strategy is associated with preserved favorable clinical outcomes and long-term survival, potentially serving as a bridge to, or a means of deferring, lung transplantation.