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Updated: Oct 19, 2026

Echocardiographic Assessment Using Subxiphoid-Only Examination for Hypotensive Patients
Published on: April 18, 2025
Intermittent hypoxaemia without orthodeoxia due to right-to-left shunting related to an elongated aorta
K L Tan1, T D Robinson, D S Celermajer
1Department of Respiratory Medicine, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.
Abstract:
An elderly woman presented with unexplained, intermittent hypoxaemia unrelated to posture. Subsequent investigations revealed intermittent and variable right-to-left interatrial shunting through a patent foramen ovale in the presence of normal pulmonary arterial and intracardiac pressures, caused by right atrial compression from a horizontal, elongated ascending aorta. Surgical closure of the foramen resulted in marked clinical improvement.
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