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Updated: Oct 6, 2025

A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Relentless Hypoxia in a Patient With Carcinoid Syndrome
Abdulrhman Alghamdi1, Afnan A Malibari2, Faisal Al-Husayni3,4
1Internal Medicine, College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Jeddah, SAU.
Abstract:
Patent foramen ovale (PFO) in patients with carcinoid heart disease (CHD) may result in hypoxia due to the presence of large right (R) to left (L) intracardiac shunts leading to hypoxia and worsening clinical condition. Percutaneous closure of the PFO can normalize oxygen saturation, relieve symptoms, and lessens left-sided heart valves involvement. We describe a case of a 70-year-old female patient with a history of small bowel neuroendocrine tumor on monthly octreotide infusion presented with worsening exertional dyspnea and hypoxia secondary to R to L intracardiac shunt through the PFO. The decision was made to close the PFO percutaneously with Amplatzer (Plymouth, MN: Abbott) PFO occluder device which resulted in immediate normalization of oxygen saturation and relief of her dyspnea.
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