Frizzelli Rino, Lettieri Corrado, Caiola Simone, Maulucci Linda, Pinzi Claudio, Agostini Francesco, Frizzelli Annalisa
Division of Internal Medicine and Setting of Cardiopulmonary Monitoring, ASST Carlo Poma - Mantova, Italy.
Division of Cardiology, ASST Carlo Poma - Mantova, Italy.
Respir Med Case Rep. 2022 May 5;37:101661. doi: 10.1016/j.rmcr.2022.101661. eCollection 2022.
In Chronic Obstructive Pulmonary Disease (COPD), hypoxemia is associated with multiple underlying mechanisms, of which one of the most significant is ventilation-perfusion (V/Q) mismatch, which is correctable with supplemental oxygen (O) therapy. Hypoxemia that is refractory to very high concentration of inspired O can be indicative of cardiac defect with shunt, e.g., a patent foramen ovale (PFO) with right-to-left (R-T-L) shunt. In hypoxemic COPD patients, the diagnosis of a PFO requires a heightened sense of clinical suspicion along with careful assessment of other underlying possibilities. Platypnea-orthodeoxia and a non-response to the hyperoxia test, while not diagnostic, increase suspicion. A correct diagnosis of interatrial bypass needs to be confirmed with transthoracic echocardiogram and contrast transesophageal echocardiography. Presently, no data are available supporting the effectiveness of PFO closure in COPD patients to relieve symptoms and correct hypoxemia. We report a case of hypoxemic COPD with platypnea-orthodeoxia syndrome due to PFO. The decision of its closure with device after echocardiographic evaluation of right ventricular function has completely corrected refractory hypoxemia with improvement of SpO and functional capacity. Thus, in selected COPD with refractory hypoxemia, closure of PFO should be considered as novel therapeutic target with improvement of quality of life and less likelihood of hospitalization.
在慢性阻塞性肺疾病（COPD）中，低氧血症与多种潜在机制相关，其中最重要的机制之一是通气-灌注（V/Q）不匹配，补充氧气（O）治疗可纠正这种情况。对高浓度吸入氧难治的低氧血症可能提示伴有分流的心脏缺陷，例如伴有右向左（R-T-L）分流的卵圆孔未闭（PFO）。在低氧血症的COPD患者中，PFO的诊断需要提高临床怀疑度并仔细评估其他潜在可能性。平卧呼吸-直立性低氧血症以及对高氧试验无反应，虽不能确诊，但会增加怀疑度。房间隔分流的正确诊断需要经胸超声心动图和对比经食管超声心动图来证实。目前，尚无数据支持在COPD患者中闭合PFO以缓解症状和纠正低氧血症的有效性。我们报告一例因PFO导致的伴有平卧呼吸-直立性低氧血症综合征的低氧血症COPD病例。在对右心室功能进行超声心动图评估后决定用装置闭合PFO，已完全纠正难治性低氧血症，SpO和功能能力得到改善。因此，在选定的难治性低氧血症COPD患者中，应考虑将闭合PFO作为改善生活质量和降低住院可能性的新治疗靶点。
