Nishizaki Mari, Ogawa Aiko, Matsubara Hiromi
Dept of Rehabilitation, National Hospital Organization Okayama Medical Center, Okayama, Japan.
Dept of Clinical Science, National Hospital Organization Okayama Medical Center, Okayama, Japan.
ERJ Open Res. 2021 Jan 25;7(1). doi: 10.1183/23120541.00725-2020. eCollection 2021 Jan.
Pulmonary arterial hypertension (PAH)-specific combination therapy improves pulmonary haemodynamics at rest in patients with PAH; nevertheless, exertional dyspnoea remains. We investigated pulmonary haemodynamic response to exercise, and the relationship to ventilatory efficiency and hypoxaemia in patients with PAH treated with combination therapy. 32 clinically stable patients with PAH undergoing combination therapy underwent cardiopulmonary exercise testing with right heart catheterisation. Haemodynamic impairment was moderate to severe before treatment. However, after treatment it was significantly improved, and the mean pulmonary arterial pressure (mPAP) at rest was <25 mmHg in 13 patients. The mPAP increased significantly from 27.9±10.7 to 45.9±16.7 mmHg (p<0.01) during exercise. The cardiac index increased inadequately, and the total pulmonary resistance (TPR) increased significantly from 5.74±3.42 to 6.58±3.82 Wood units (p<0.01). The mPAP/cardiac output (CO) slope was steep (10.0±6.7 mmHg·min·L). It significantly correlated with both the minute ventilation/carbon dioxide output slope (r=0.51, p<0.01) and peripheral arterial oxygen saturation/workload slope (r=-0.41, p=0.02). In addition, the mPAP/CO slope correlated significantly with mPAP at rest (r=0.73, p<0.01) and TPR at rest (r=0.64, p<0.01). Even after pulmonary haemodynamics at rest was significantly improved in PAH patients with PAH-specific combination therapy, the mPAP/CO slope was steep and the steep mPAP/CO slope related to decreased ventilatory efficiency and the severity of hypoxaemia. The mPAP/CO slope was steeper in patients with higher mPAP and TPR at rest.
肺动脉高压（PAH）特异性联合治疗可改善PAH患者静息时的肺血流动力学；然而，运动性呼吸困难仍然存在。我们研究了联合治疗的PAH患者运动时的肺血流动力学反应，以及与通气效率和低氧血症的关系。32例接受联合治疗的临床稳定的PAH患者接受了心肺运动试验及右心导管检查。治疗前血流动力学损害为中度至重度。然而，治疗后明显改善，13例患者静息时平均肺动脉压（mPAP）<25 mmHg。运动期间，mPAP从27.9±10.7显著增加至45.9±16.7 mmHg（p<0.01）。心脏指数增加不足，总肺阻力（TPR）从5.74±3.42显著增加至6.58±3.82伍德单位（p<0.01）。mPAP/心输出量（CO）斜率较陡（10.0±6.7 mmHg·min·L）。它与分钟通气量/二氧化碳排出量斜率（r=0.51，p<0.01）和外周动脉血氧饱和度/工作量斜率（r=-0.41，p=0.02）均显著相关。此外，mPAP/CO斜率与静息时mPAP（r=0.73，p<0.01）和静息时TPR（r=0.64，p<0.01）显著相关。即使PAH患者通过PAH特异性联合治疗使静息时肺血流动力学得到显著改善，mPAP/CO斜率仍较陡，且mPAP/CO斜率较陡与通气效率降低和低氧血症严重程度相关。静息时mPAP和TPR较高的患者mPAP/CO斜率更陡。
