Suda Rika, Tanabe Nobuhiro, Ishida Keiichi, Kato Fumiaki, Urushibara Takashi, Sekine Ayumi, Nishimura Rintaro, Jujo Takayuki, Sugiura Toshihiko, Shigeta Ayako, Sakao Seiichiro, Tatsumi Koichiro
Department of Respirology, Graduate School of Medicine, Chiba University, Chiba, Japan.
Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, Chiba, Japan.
Respirology. 2017 Jan;22(1):179-186. doi: 10.1111/resp.12883. Epub 2016 Sep 11.
Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disease in some patients, despite improved treatments. Microvasculopathy has been implicated in the poor outcomes of patients with CTEPH. A reduction in the diffusing capacity for carbon monoxide (DL ) was previously suggested to indicate microvasculopathy in CTEPH patients; therefore, we assessed DL /alveolar ventilation (DL /V ) as a prognostic and pathophysiological marker in CTEPH.
We performed a retrospective cohort study of 214 CTEPH patients consecutively diagnosed between 1986 and 2011. After exclusion of 24 patients because of missing DL data or severe obstructive impairment, the mortality rates of medically treated patients classified with normal or decreased DL values were compared, and prognostic factors were determined. The relationship between long-term surgical outcomes and DL /V was also investigated.
Ninety-one inoperable patients were treated medically, two of whom underwent balloon pulmonary angioplasty. Ninety-nine underwent pulmonary endarterectomy. The 5-year survival rate of medically treated patients was significantly lower in patients with decreased DL /V than in those with normal values (61.4% vs 90.4%, P = 0.017). Decreased preoperative DL /V was associated with a smaller percent decrease in post-operative pulmonary vascular resistance, but not with the extent of proximal thrombi; these results may support our hypothesis that DL reflects microvascular involvement.
Decreased DL /V was associated with poor outcomes of medically treated CTEPH patients; and may be useful for identifying high-risk patients, potentially leading to earlier and more appropriate interventions.
尽管治疗方法有所改进，但慢性血栓栓塞性肺动脉高压（CTEPH）在部分患者中仍是一种进行性疾病。微血管病变被认为与CTEPH患者的不良预后有关。先前有研究表明，一氧化碳弥散量（DL）降低提示CTEPH患者存在微血管病变；因此，我们评估了DL/肺泡通气量（DL/V）作为CTEPH的预后和病理生理标志物。
我们对1986年至2011年间连续诊断的214例CTEPH患者进行了一项回顾性队列研究。排除24例因DL数据缺失或严重阻塞性损害的患者后，比较了DL值正常或降低的接受药物治疗患者的死亡率，并确定了预后因素。还研究了长期手术结果与DL/V之间的关系。
91例无法手术的患者接受了药物治疗，其中2例接受了球囊肺动脉血管成形术。99例接受了肺动脉内膜剥脱术。DL/V降低的接受药物治疗患者的5年生存率显著低于DL值正常的患者（61.4%对90.4%，P = 0.017）。术前DL/V降低与术后肺血管阻力降低的百分比减小有关，但与近端血栓的范围无关；这些结果可能支持我们的假设，即DL反映微血管受累情况。
DL/V降低与接受药物治疗的CTEPH患者的不良预后有关；可能有助于识别高危患者，从而可能实现更早、更恰当的干预。
