Pulmonary endarterectomy for distal chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension can be cured by pulmonary endarterectomy. Operability assessment remains a major concern, because there are no well-defined criteria to discriminate proximal from distal obstructions, and surgical candidacy depends mostly on the surgeon's experience. The intraoperative classification of chronic thromboembolic pulmonary hypertension describes 4 types of lesions, based on anatomy and location. We describe our recent experience with the more distal (type 3) disease.

More than 500 pulmonary endarterectomies were performed at Foundation I.R.C.C.S. Policlinico San Matteo (Pavia, Italy). Because of recent changes in the patient population, 331 endarterectomies performed from January 2008 to December 2013 were analyzed. Two groups of patients were identified according to the intraoperative classification: proximal (type 1 and type 2 lesions, 221 patients) and distal (type 3 lesions, 110 patients).

The number of endarterectomies for distal chronic thromboembolic pulmonary hypertension increased significantly over time (currently ∼37%). Deep venous thrombosis was confirmed as a risk factor for proximal disease, whereas patients with distal obstruction had a higher prevalence of indwelling intravascular devices. Overall hospital mortality was 6.9%, with no difference in the 2 groups. Postoperative survival was excellent. In all patients, surgery was followed by a significant and sustained improvement in hemodynamic, echocardiographic, and functional parameters, with no difference between proximal and distal cases.

Although distal chronic thromboembolic pulmonary hypertension represents the most challenging situation, the postoperative outcomes of both proximal and distal cases are excellent. The diagnosis of inoperable chronic thromboembolic pulmonary hypertension should be achieved only in experienced centers, because many patients who have been deemed inoperable might benefit from favorable surgical outcomes.