Thoracic research scholarship 1988: pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension at the University of California, San Diego

At the University of California, San Diego pulmonary thromboendarterectomy (PTE) has emerged as an effective measure in the treatment of chronic thromboembolic pulmonary hypertension. Unresolved emboli become organized by incorporation into the vascular wall and may form strictures, webs, bands and/or membranous occlusions and cause pulmonary hypertension refractory to medical treatment. When pulmonary vascular resistance exceeds 300 dyn.sec.cm-5 and the vascular wall changes are located to begin at or proximal to the lobar artery level, surgery is indicated. The operation is performed using cardiopulmonary bypass, deep hypothermia and periods of circulatory arrest. The dissection of each segmental artery is carried out in the media layer from separate incisions in the right and left pulmonary artery at the level of the pericardial flexion. Pulmonary reperfusion edema may complicates the postoperative course, and pulmonary hemorrhage, respiratory insufficiency necessitating prolonged ventilatory support and secondary multi organ failure are main causes of hospital mortality. Between October 1984 and September 1988 103 patients with a mean age of 50 +/- 16 years underwent PTE. Consequently, pulmonary vascular resistance could be reduced from 788 +/- 370 to 299 +/- 150 dyn.sec.cm-5 and cardiac index increased from 2.0 +/- 0.6 to 3.2 +/- 0.8 l/min-m2. Hospital mortality was 11.7% (12/103 patients). Thus, pulmonary thromboendarterectomy effectively reduces pulmonary hypertension at an acceptable low risk. The results indicate that patients should be diagnose and referred for surgery as early as possible.