University of Cambridge, UK.
Eur Respir J. 2012 Sep;40(3):612-7. doi: 10.1183/09031936.00134111. Epub 2012 Feb 23.
Flow-directed pulmonary artery occlusion is posited to enable partitioning of vascular resistance into small and large vessels. As such it may have a role in assessment for pulmonary endarterectomy. To test if the occlusion technique distinguished small from large vessel disease we studied 59 subjects with chronic thromboembolic pulmonary hypertension (CTEPH), idiopathic pulmonary arterial hypertension (IPAH), and connective tissue disease (CTD)-associated PAH. At right heart catheterisation, occlusion pressures were recorded. With fitting of the pressure decay curve, pulmonary vascular resistance was partitioned into downstream (small vessels) and upstream (large vessels, Rup). 47 patients completed the study; 14 operable CTEPH, 15 inoperable CTEPH, 13 idiopathic or CTD-PAH and five post-operative CTEPH. There was a significant difference in mean Rup in the proximal operable CTEPH group 87.3 (95% CI 84.1-90.5); inoperable CTEPH mean 75.8 (95% CI 66.76-84.73), p=0.048; and IPAH/CTD, mean 77.1 (95% CI 71.86-82.33), p=0.003. Receiver operating characteristic curves to distinguish operable from inoperable CTEPH demonstrated an area under the curve of 0.75, p=0.0001. A cut-off of 79.3 gave 100% sensitivity (95% CI 73.5-100%) but 57.1% specificity (95% CI 28.9-82.3%). In a subgroup analysis of multiple lobar sampling there was demonstrable heterogeneity. Rup is significantly increased in operable proximal CTEPH compared with non-operable distal CTEPH and IPAH/CTD-PAH. Rup variability in patients with CTEPH and PAH is suggestive of pathophysiological heterogeneity.
肺动脉阻断术被认为可以将血管阻力分为小血管和大血管。因此,它可能在肺动脉内膜剥脱术的评估中发挥作用。为了测试该阻断技术是否能区分小血管和大血管疾病,我们研究了 59 例慢性血栓栓塞性肺动脉高压(CTEPH)、特发性肺动脉高压(IPAH)和结缔组织疾病(CTD)相关肺动脉高压(PAH)患者。在右心导管检查中,记录了阻断压力。通过拟合压力衰减曲线,将肺血管阻力分为下游(小血管)和上游(大血管,Rup)。47 例患者完成了研究;14 例可手术 CTEPH、15 例不可手术 CTEPH、13 例特发性或 CTD-PAH 和 5 例手术后 CTEPH。近端可手术 CTEPH 组的平均 Rup 存在显著差异,为 87.3(95%CI84.1-90.5);不可手术 CTEPH 组平均为 75.8(95%CI66.76-84.73),p=0.048;以及 IPAH/CTD,平均为 77.1(95%CI71.86-82.33),p=0.003。区分可手术与不可手术 CTEPH 的受试者工作特征曲线显示曲线下面积为 0.75,p=0.0001。截断值为 79.3 时,敏感性为 100%(95%CI73.5-100%),特异性为 57.1%(95%CI28.9-82.3%)。在多叶取样的亚组分析中,存在可察觉的异质性。与不可手术的远端 CTEPH 和 IPAH/CTD-PAH 相比,近端可手术 CTEPH 的 Rup 显著增加。CTEPH 和 PAH 患者的 Rup 变异性提示存在病理生理异质性。