# Platypnea‐Orthodeoxia Syndrome Post‐Pneumonectomy: A Case of Right‐To‐Left Shunting and Successful PFO Closure

## TL;DR

A patient with platypnea-orthodeoxia syndrome after pneumonectomy showed right-to-left shunting, which was successfully treated with PFO closure.

## Contribution

This case highlights successful PFO closure as a treatment for platypnea-orthodeoxia syndrome following pneumonectomy.

## Key findings

- Right-to-left shunting was identified via transesophageal echocardiogram in a patient with POS post-pneumonectomy.
- PFO closure resolved dyspnea and hypoxemia in the patient.
- Comprehensive evaluation is crucial for diagnosing POS in patients with complex cardiopulmonary histories.

## Abstract

Platypnea‐orthodeoxia syndrome is a rare disorder characterized by dyspnea (platypnea) and arterial desaturation (orthodeoxia) in the upright position, with symptom relief upon lying down. This syndrome is commonly associated with cardiac anomalies, particularly patent foramen ovale (PFO), where increased right atrial pressure facilitates right‐to‐left shunting, leading to hypoxemia. Other associated conditions include cirrhosis, pericardial effusion, and pneumonectomy. We present a 32‐year‐old female with a history of right pneumonectomy for invasive aspergillosis who presented with worsening dyspnea and a greater than 10% drop in SpO2 when seated compared to the supine position. Initial imaging demonstrated rightward displacement of thoracic structures, including the right atrium, but a transthoracic echocardiogram was negative for intracardiac shunt. Due to persistent hypoxemia, a transesophageal echocardiogram was performed, revealing a right‐to‐left shunt, an atrial septal aneurysm, and a prominent Eustachian valve. The patient underwent successful PFO closure, leading to the complete resolution of both dyspnea and hypoxemia. This case emphasizes the importance of comprehensive diagnostic evaluation in patients with POS, especially those with complex cardiopulmonary histories.