Outcomes of pulmonary endarterectomy for treatment of extreme thromboembolic pulmonary hypertension

Pulmonary endarterectomy is the operation of choice for thromboembolic pulmonary hypertension. As the largest referral center for thromboembolic pulmonary hypertension in the world, we are frequently asked whether patients with extreme pulmonary hypertension (pulmonary artery systolic pressure >100 mm Hg) can safely undergo this operation with therapeutic benefit. To determine whether patients with pulmonary artery systolic pressures of greater than 100 mm Hg have favorable outcomes after pulmonary endarterectomy, we reviewed the outcomes of 743 patients who underwent this operation between 1999 and 2004. We compared hemodynamic and outcome parameters of 65 patients (group 1: 26 male and 39 female patients; mean age, 49.5 years) who had preoperative pulmonary artery systolic pressures of greater than 100 mm Hg with 678 patients (group 2: 314 male and 364 female patients; mean age, 50.3 years) with preoperative pulmonary artery systolic pressures of less than 100 mm Hg. Group 1 patients had a greater overall diminution in pulmonary vascular resistance (mean decrease: 926.7 ± 511.1 vs 546.4 ± 365.1 dynes · sec · cm −5, P < .01) and reduction in pulmonary artery systolic pressure (mean decrease: 50.5 ± 18.7 vs 27.2 ± 18.6 mm Hg, P < .05), with similar improvement in cardiac output (mean increase: 1.53 ± 1.47 vs 1.55 ± 1.58 L/min) compared with values seen in group 2 patients. Although length of hospital stay was similar for the 2 groups, overall perioperative survival was slightly lower in group 1 patients (89.2% [58/65] for group 1 vs 96.5% [654/678] for group 2). Patients with extreme pulmonary hypertension manifest a higher rate of postoperative reperfusion edema, leading to longer days of intubation compared with group 2 patients. Pulmonary endarterectomy can be performed safely in patients with severe thromboembolic pulmonary hypertension. The magnitude of preoperative pulmonary artery systolic pressure or pulmonary vascular resistance is not a contraindication for surgical intervention. Indeed, patients with extreme pulmonary hypertension might benefit the most from this operation.