Outcome after pulmonary endarterectomy for segmental chronic thromboembolic pulmonary hypertension

Objective: Determine the long-term outcome and need for additional therapy after pulmonary endarterectomy (PEA) for segmental chronic thromboembolic pulmonary hypertension. Methods: Retrospective analysis of a prospective cohort of 401 consecutive Canadian patients undergoing PEA between August 2005 and March 2020 in Toronto. The outcome of segmental disease defined as Jamieson type 3 was compared with more proximal disease defined as Jamieson type 1 and 2. The cohort was divided into 3 intervals to analyze the trend over time: 2005-2010, 2011-2015, and 2016-2020. Results: Type 3 disease accounted for 41% of patients undergoing PEA durig 2016-2020 compared with 7% in 2006-2010. Total pulmonary vascular resistance improved by 505 +/- 485 dynes/s/cm(-5) in type 3 disease and by 593 +/- 452 dynes/s/cm(-5) in type 1 or 2 disease (P = .07). Mortality after PEA was similar between type 3 and type 1 and 2 disease at 30-days (2.8% vs 2.3%; P = .8) and at 1 year (7.7% vs 5.5%; P = .4). At 5 years, the survival was lower in type 3 disease (80% vs 91% in type 1 or 2 disease; P = .002). Type 3 disease was an independent predictor for the initiation of pulmonary hypertension-targeted medical therapy after PEA with a cumulative incidence of 38% at to years compared with 20% in type and 2 disease (P < .0001). Post-PEA balloon pulmonary angioplasty was predominantly performed in type 3 disease (8% vs 1% in more type 1 or 2 disease; P = .0002). Conclusions: PEA achieved excellent early and long-term results in segmental chronic thromboembolic pulmonary hypertension. However, patients with segmental disease are at increased risk of requiring additional therapy after PEA and should be carefully monitored.