Platypnoea syndrome caused by atrial septal aneurysm.

A patient with platypnoea after right pneumonectomy and radiotherapy is described. On transoesophageal contrast echocardiography and cardiac catheterization, an atrial septal aneurysm with interatrial right-to-left shunting was detected. Symptoms disappeared after surgical correction. To the best of our knowledge, this is the first report of a patient with a septal aneurysm and severe platypnoea.