Successful Revascularization of Chronic Total Occlusions in Patients With Chronic Thromboembolic Pulmonary Disease

BACKGROUND: Chronic thromboembolic pulmonary disease (CTEPD) leads to chronic total occlusions (CTOs) of the pulmonary arteries in a minority of patients. Treatment of CTOs with balloon pulmonary angioplasty (BPA) may substantially improve patient hemodynamics but presents unique technical challenges and has previously been associated with a low success rate. METHODS: A prospective registry of CTEPD patients who underwent CTO BPA at the University of Washington from August 2019 to July 2024 was included. Rates of technical success, methods of successful revascularization, and hemodynamic outcomes are reported. Outcomes were compared to a cohort of non-CTO BPA interventions, evaluating differences in hemodynamic outcomes and overall complications. RESULTS: Eighty-four CTO lesions were intervened upon in 37 patients. On a per-lesion basis, 94% of CTOs were revascularized, with an 80% success rate on the first attempt. Most cases of subintimal and/or extravascular entry were treated with the novel Microcatheter Injection, Retraction, and Reentry (MIRaR) technique. Follow-up patency rate was 96%, and the total per-procedure complication rate was 10%, the majority of which were clinically insignificant. Although mean pulmonary artery pressure, cardiac index, pulmonary vascular resistance, and pulmonary vascular compliance were significantly worse in the CTO group at baseline, no significant differences persisted after intervention. Both total and clinically meaningful complication rates were similar between cohorts. CONCLUSIONS: We report the highest rate of successful CTO revascularization to date with a low overall intra-procedural complication rate. Novel technical approaches to managing subintimal wire entry may be responsible for our observed success.