Yandrapalli Srikanth, Tariq Sohaib, Kumar Jessica, Aronow Wilbert S, Malekan Ramin, Frishman William H, Lanier Gregg M
Cardiol Rev. 2018 Mar/Apr;26(2):62-72. doi: 10.1097/CRD.0000000000000164.
Chronic thromboembolic pulmonary hypertension (CTEPH), classified as World Health Organization (WHO) group 4 pulmonary hypertension (PH), is an interesting and rare pulmonary vascular disorder secondary to mechanical obstruction of the pulmonary vasculature from thromboembolism resulting in PH. The pathophysiology is complex, beginning with mechanical obstruction of the pulmonary arteries, which eventually leads to arteriopathic changes and vascular remodeling in the nonoccluded arteries and in the distal segments of the occluded arteries mediated by thrombus nonresolution, abnormal angiogenesis, endothelial dysfunction, and various local growth factors. Based on available data, CTEPH is a rare disease entity occurring in a small proportion (0.5-3%) of patients after acute pulmonary embolism with an annual incidence ranging anywhere between 1 and 7 cases per million population. It is often underdiagnosed or misdiagnosed as idiopathic pulmonary arterial hypertension due to a lack of clinical suspicion or the under-utilization of radionuclide ventilation/perfusion scan. Although the current standard remains planar ventilation/perfusion scintigraphy as the initial imaging study to screen for CTEPH, and invasive pulmonary angiography with right heart catheterization as confirmatory modalities, they are likely to be replaced by modalities that can provide both anatomic and functional data while minimizing radiation exposure. Surgery is the gold standard treatment and offers better improvements in clinical and hemodynamic parameters compared with medical therapy. The management of CTEPH requires a multidisciplinary team, operability assessment, experienced surgical center, and the consideration of medical PH-directed therapies in patients who have inoperable disease, in addition to supportive therapies. Although, balloon pulmonary angioplasty is gaining interest to improve pulmonary hemodynamics and symptoms in CTEPH patients not amenable to surgery, further investigative randomized studies are needed to validate its use. It is very important for the present-day physician to be familiar with the disease entity and its appropriate evaluation to facilitate early diagnosis and appropriate management.
慢性血栓栓塞性肺动脉高压（CTEPH）被归类为世界卫生组织（WHO）第4组肺动脉高压（PH），是一种有趣且罕见的肺血管疾病，继发于肺血管因血栓栓塞导致的机械性阻塞，进而引起PH。其病理生理学较为复杂，始于肺动脉的机械性阻塞，最终导致未阻塞动脉以及由血栓未溶解、异常血管生成、内皮功能障碍和各种局部生长因子介导的阻塞动脉远端节段发生动脉病变和血管重塑。根据现有数据，CTEPH是一种罕见的疾病实体，在急性肺栓塞患者中占比很小（0.5 - 3%），年发病率为每百万人口1至7例。由于缺乏临床怀疑或放射性核素通气/灌注扫描使用不足，该病常被漏诊或误诊为特发性肺动脉高压。尽管目前的标准仍是平面通气/灌注闪烁扫描作为筛查CTEPH的初始影像学检查，以及有创肺血管造影联合右心导管检查作为确诊手段，但它们可能会被能够提供解剖和功能数据同时将辐射暴露降至最低的检查方法所取代。手术是金标准治疗方法，与药物治疗相比，在临床和血流动力学参数方面能带来更好的改善。CTEPH的管理需要多学科团队、可手术性评估、经验丰富的手术中心，对于无法手术的患者，除了支持性治疗外，还需考虑针对PH的药物治疗。尽管球囊肺动脉成形术在改善不适于手术的CTEPH患者的肺血流动力学和症状方面越来越受到关注，但仍需要进一步的随机研究来验证其应用。对于当代医生来说，熟悉这种疾病实体及其恰当评估以促进早期诊断和合理管理非常重要。
