Dyspnoea on exertion

A 64-year-old woman visited our hospital with an initial symptom of dyspnoea on exertion. For the past 4 months she had shortness of breath when she walked approximately 100 meters or went up 10 to 20 steps of a staircase. She visited her neighbouring hospital 1 month before visiting our hospital where she received a diagnosis of bilateral pleural effusions and seven sessions of thoracentesis; however, no clinical diagnosis could be made although her dyspnoea on exertion was slightly improved by the frequent thoracentesis.