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Updated: May 22, 2026

Chronic Ovine Model of Right Ventricular Failure and Functional Tricuspid Regurgitation
Published on: March 17, 2023
Persistent Hypoxia After Tricuspid Valve Replacement
John Nguyen1, Thomas Merino2, Vijay Kandula1
1Texas A&M College of Medicine, Baylor Scott & White Medical Center-Round Rock, Round Rock, Texas, USA.
Background:
Transcatheter tricuspid valve replacement (TTVR) is a novel therapy for symptomatic severe tricuspid regurgitation in high-risk surgical patients. Platypnea-orthopnea syndrome has not previously been described as a complication of TTVR.
Case Summary:
A 76-year-old woman with symptomatic severe tricuspid regurgitation underwent successful TTVR but developed persistent hypoxia despite negative pulmonary work-up. Her hypoxia followed a platypnea-orthodeoxia pattern. Echocardiography revealed a patent foramen ovale (PFO) with right-to-left shunting. She then underwent successful percutaneous PFO closure, with resolution of her hypoxia.
Discussion:
Acute post-TTVR anatomic and hemodynamic changes can include right atrial distortion and right ventricular dysfunction in the absence of pulmonary hypertension. These changes may acutely worsen right-sided pressures, leading to right-to-left shunting through an existing PFO.
Take-Home Messages:
Persistent hypoxia with a platypnea-orthodeoxia pattern immediately after TTVR should prompt thorough work-up including evaluation for PFO. Percutaneous PFO closure can address platypnea-orthodeoxia syndrome in this setting.
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