{
  "abstract": "Platypnoea–orthodeoxia syndrome (POS) is a rare cause of posture-dependent hypoxaemia, usually linked to intracardiac right-to-left shunts. We report an elderly woman with progressive dyspnoea and recurrent falls whose oxygen saturation fell from 95% supine to 84% upright. Imaging showed kyphoscoliosis with partial right hemi-diaphragmatic dysfunction. Supine and upright contrast transthoracic echocardiography demonstrated delayed bubble appearance, excluding an intracardiac shunt and suggesting an intrapulmonary mechanism. CT pulmonary angiography and Tc-99m macroaggregated albumin scintigraphy ruled out pulmonary arteriovenous malformations, indicating posture-dependent ventilation–perfusion mismatch as the cause. Comprehensive geriatric assessment identified frailty and limited physiological reserve, guiding conservative management with pulmonary rehabilitation and fall-prevention measures. This case emphasises the importance of postural pulse oximetry, sequential imaging and geriatric assessment in diagnosing POS in older adults and describes a rare extracardiac mechanism without cardiac or vascular shunting.",
  "authors": [
    {
      "affiliations": [
        "Department Of Geriatric Medicine, All India Institute Of Medical Sciences, New Delhi, Delhi, India"
      ],
      "name": "Venugopal Mantry"
    },
    {
      "affiliations": [
        "Department Of Geriatric Medicine, All India Institute Of Medical Sciences, New Delhi, Delhi, India"
      ],
      "name": "Swarup Das"
    },
    {
      "affiliations": [
        "Department Of Geriatric Medicine, All India Institute Of Medical Sciences, New Delhi, Delhi, India"
      ],
      "name": "Avinash Chakrawarty"
    }
  ],
  "title": "Platypnoea–orthodeoxia from kyphoscoliosis and diaphragmatic dysfunction without intracardiac shunt on transthoracic echocardiography",
  "uid": "1ff3b1a0-91c4-5201-8a27-8a53909e80b6"
}