Pre-operative" diastolic pulmonary vascular pressure gradient (DPG) "correlated with post-operative" pulmonary vascular resistance (PVR) "in this series of 394 consecutive" pulmonary thromboendarterectomy procedures. Preoperative" fractional pulse pressure "showed no correlation with post-operative PVR. Just 3 post-operative deaths were observed in this series - all occurring with a DPG greater than the observed median value.