Evidence Hub

Unexplained Positional Hypoxemia in an Elderly Patient: A Case of Platypnea-Orthodeoxia Syndrome

Villalobos De Ycaza MA, López Saborio GM, Mora Murillo JJ, Alvarado Sanabria E, Quirós Alvarado M, Leandro Sandí K

Cureus, 2026

Abstract

Patent foramen ovale is a congenital cardiac condition that may remain clinically silent until advanced age. One of its potential manifestations is platypnea-orthodeoxia syndrome, characterized by hypoxemia in the upright position with improvement in the supine position. Diagnosis may be delayed and challenging in older adults, as hypoxemia is frequently attributed to alternative conditions such as infection, pulmonary disease, or age-related physiological changes. We report the case of an 88-year-old man admitted with suspected urosepsis in whom refractory hypoxemia of unclear origin was documented despite unremarkable pulmonary and initial cardiac imaging studies. Marked oxygen desaturation occurred when seated or standing and resolved in the supine position. Two-dimensional transesophageal echocardiography with bubble study confirmed the presence of a patent foramen ovale with right-to-left shunting. Percutaneous closure was successfully performed, resulting in complete resolution of hypoxemia. Notably, the patient also experienced a reduction in the frequency and intensity of migraine episodes following the intervention. To our knowledge, reports of symptomatic platypnea-orthodeoxia syndrome requiring percutaneous closure in patients of such advanced age remain limited. This case emphasizes the importance of considering intracardiac shunting in older patients with unexplained positional hypoxemia and supports the role of individualized decision-making regarding patent…

How strong is the evidence?

Evidence Hub reads this as a case report, done in people. Its evidence level is 5 of 5 (Very low · case / narrative / animal / in vitro / in silico). Case reports, narrative reviews, and animal, cell or computer-model studies give the weakest evidence for human health.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free