Significance of Patent Foramen Ovale in Patients with GOLD Stage II Chronic Obstructive Pulmonary Disease (COPD)

Unexplained hypoxemia in COPD with cardiac shunt

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 (O₂) therapy. Hypoxemia that is refractory to very high concentration of inspired O₂ 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 SpO₂ 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.

European position paper on the management of patients with patent foramen ovale. Part II - Decompression sickness, migraine, arterial deoxygenation syndromes and select high-risk clinical conditions

Patent foramen ovale (PFO) is implicated in the pathogenesis of a number of medical conditions but to date only one official position paper related to left circulation thromboembolism has been published. This interdisciplinary paper, prepared with the involvement of eight European scientific societies, reviews the available evidence and proposes a rationale for decision making for other PFO-related clinical conditions. In order to guarantee a strict evidence-based process, we used a modified grading of recommendations, assessment, development, and evaluation (GRADE) methodology. A critical qualitative and quantitative evaluation of diagnostic and therapeutic procedures was performed, including assessment of the risk/benefit ratio. The level of evidence and the strength of the position statements were weighed and graded according to predefined scales. Despite being based on limited and observational or low-certainty randomised data, a number of position statements were made to frame PFO management in different clinical settings, along with suggestions for new research avenues. This interdisciplinary position paper, recognising the low or very low certainty of existing evidence, provides the first approach to several PFO-related clinical scenarios beyond left circulation thromboembolism and strongly stresses the need for fresh high-quality evidence on these topics.

Potential Role of Patent Foramen Ovale in Exacerbating Hypoxemia in Chronic Pulmonary Disease

Patent foramen ovale has been associated with multiple pulmonary diseases, such as pulmonary hypertension, platypnea-orthodeoxia syndrome, and chronic obstructive pulmonary disease. A connection between patent foramen ovale and chronic pulmonary disease was first described more than 2 decades ago in case reports associating patent foramen ovale with more severe hypoxemia than that expected based on the severity of the primary pulmonary disease. It has been suggested that patients with both chronic pulmonary disease and patent foramen ovale are subject to severe hypoxemia because of the right-to-left shunt. Furthermore, investigators have reported improved systemic oxygenation after patent foramen ovale closure in some patients with chronic pulmonary disease. This review focuses on the association between chronic pulmonary disease and patent foramen ovale and on the dynamics of a right-to-left shunt, and it considers the potential benefit of patent foramen ovale closure in patients who have hypoxemia that is excessive in relation to the degree of their pulmonary disease.