Evaluation of persistent pulmonary hypertension after acute pulmonary embolism

Background: Better knowledge of the evolution of persistent pulmonary hypertension after acute pulmonary embolism (PE) is required to optimize the indication and timing of pulmonary endarterectomy (PEA). Methods: We reviewed our experience with 17 consecutive patients demonstrated to have persistent pulmonary hypertension after acute massive (n = 1), submassive (n = 7), or recurrent PE (n = 9). Results: After a median of IS weeks of anticoagulation (range, 12 to 30 weeks) since the last PE, 10 patients showed residual pulmonary artery systolic pressure (PAsP) > 50 mm Hg. These patients demonstrated a significant progression in PAsP over the ensuing 6 to 12 months, from 73 +/- 14 to 101 +/- 26 mm Hg (p = 0.005) [mean +/- SD], and eight patients were found to be suitable candidates for PEA. In contrast, among seven patients with residual PAsP from 35 to 40 nun Hg (n = 3) and 41 to 50 mm Hg (n = 4), six patients had evidence of residual perfusion defects on the ventilation/perfusion scan and CT. The PAsP did not change significantly over the ensuing 6 to 12 months, except in two patients who had new episodes of acute PE. Conclusions: Two groups of patients can be identified based on the degree of residual pulmonary hypertension after acute PE. Patients with residual PAsP > 50 mm Hg should be evaluated for PEA since their pulmonary artery pressures will significantly progress over the ensuing 6 to 12 months despite the absence of recurrent PE. In contrast, patients with PAsP from 35 to 50 nun Hg are at risk for severe pulmonary hypertension if new PE occurs, and should therefore be closely monitored.