Pulmonary Endarterectomy for Chronic Thromboembolic Pulmonary Hypertension

Definition and Procedure

Pulmonary endarterectomy is performed via median sternotomy on cardiopulmonary bypass with deep hypothermia and periods of complete circulatory arrest to provide adequate visibility, as recommended by the European Society of Cardiology 1, 3
The main pulmonary arteries are incised, and the endarterectomy plane is followed circumferentially down to segmental and sometimes subsegmental branches of each lobar artery using special suction dissectors, according to the European Heart Journal 1

Patients with CTEPH should be promptly evaluated for pulmonary endarterectomy at an experienced center, even if symptoms are mild, with a Class I recommendation and Level of Evidence B from the American Heart Association 4, 5
Selection criteria include New York Heart Association (NYHA) functional class III or IV symptoms, preoperative pulmonary vascular resistance greater than 300 dyn·s·cm⁻⁵, and surgically accessible thrombi in main, lobar, or segmental pulmonary arteries, as stated by the European Heart Journal 1, 6
There is no upper limit of pulmonary vascular resistance (PVR) or degree of right ventricular dysfunction that absolutely excludes a patient from surgery at experienced centers, according to the American Heart Association 5, 7

Patients can be postoperatively classified into four categories based on lesion location, including Type 1: Fresh thrombus in the main lobar pulmonary arteries, Type 2: Thickening and fibrosis of the intima proximally to the segmental arteries, Type 3: Involvement of distal segmental arteries only, and Type 4: Distal arteriolar involvement without visible thromboembolic disease, as described by the European Heart Journal 1

Perioperative mortality is related to disease severity, with a mortality rate of 4% in patients with preoperative PVR <900 dyn·s·cm⁻⁵ and 20% in those with PVR >1200 dyn·s·cm⁻⁵, as reported by the European Heart Journal 1
Functional results are excellent and generally sustained over time, with a 3-year survival rate of about 80% and long-term survival rates of 75-92.3% after 6 years, according to the European Heart Journal and the American Heart Association 1, 7

Patients with CTEPH should receive indefinite therapeutic anticoagulation after surgery in the absence of contraindications, with a Class I recommendation and Level of Evidence C from the American Heart Association 4, 5
PAH-specific medical therapy may be considered for patients with residual pulmonary hypertension after operation, as stated by the American Heart Association 5, 7