Surgical treatment of chronic thromboembolic pulmonary hypertension

There are only limited treatment options for patients with chronic thromboembolic pulmonary hypertension in Canada.

To conduct a case-series study to assess the effectiveness of surgical endarterectomy of the pulmonary artery.

Twenty-one patients with chronic thromboembolic pulmonary hypertension were admitted for surgery between July 1995 and October 1999. Clinical, laboratory and radiological data were collected for all patients who then underwent pulmonary thromboendarterectomy.

Thirteen men and eight women between 22 and 71 years of age underwent surgery. The main presenting complaint was dyspnea on exertion. Pulmonary vascular resistance ranged from 382 to 1694 dynes s cm-5 with a mean of 765+/-372 dynes s cm-5 (normal is less than 180 dynes s cm-5) with a mean cardiac index of 2.2+/-0.9 L/min/m2. Two patients had concomitant tricuspid valve replacement and one patient had coronary bypass grafting. In three cases, the surgery involved a repeat sternotomy. After surgery, there was a significant drop in the pulmonary vascular resistance (208+/-92 dynes s cm-5, P<0.05) and a concomitant rise in the cardiac index to a mean of 3.1+/-0.6 L/min/m2 (P<0.05). There was one death in a patient who also had severe chronic obstructive pulmonary disease. Of the remaining patients, all but two showed significant clinical improvement. Spiral computed tomography postsurgery demonstrated improvement in pulmonary perfusion with either complete clearing or significant improvement in the mosaic perfusion pattern. Right ventricular function and pressure on echocardiogram improved in all but two patients.

Pulmonary thromboendarterectomy provides effective treatment for chronic thromboembolic pulmonary hypertension.