Objective To determine the parameters, including pulmonary vascular resistance (PVR), that will predict suitability for surgery for chronic thromboembolic pulmonary hypertension (CTEPH) patients.

Method 106 cases of surgical accessible CTEPH admitted into Anzhen Hospital from March 2002 to January 2011 were retrospectively reviewed and were classified as operable group (Group A, n=94)or inoperable group (Group B, n=12). The occluded pulmonary segments (OPS) were assessed through ventilation/perfusion scintigraphy, and PVR were measured through right heart catheterisation, and the ratio of PVR/OPS was calculated. Members from Group A received pulmonary thromboendarterectomy (PTE).

Result There were three (3.19%) early deaths post the PTE procedure. With mean follow-up of (45.8±31.1) months, there were three late deaths; the actuarial survival at 5 years was (94.9±3.3) %. The PVR and PVR/OPS in Group B were significantly higher than that in Group A. The PVR/OPS of early death and late death after PTE procedures were significantly higher than that of early survivor and late survivor respectively. PVR/OPS <100 dynes/s/cm⁵/OPS has a much better specificity than PVR (92.1% vs 69.3%), and also a much better sensitivity than PVR (100% vs 33.3%. The difference among the two AUCs under their ROC curves reached a statistical significance (z test, Z=1.9917, p=0.046).

Conclusion To define operability of surgical accessible CTEPH, PVR/OPS have a much better specificity, sensitivity, and AUCs than PVR. PVR/OPS may serve as a new classifier for the CTEPH operability.