Orthopnea refers to

• A. Shortness of breath while standing
• B. Shortness of breath while lying down
• C. Chest pain with exertion
• D. Palpitations

Answer: (B)

Orthopnea is shortness of breath that occurs when you lie flat and is relieved by sitting up or propping yourself on pillows. This happens because lying down increases venous return to the heart, which can raise pressure in the pulmonary circulation and cause fluid to back up in the lungs—common in left-sided heart failure. So the best description is shortness of breath while lying down, improved when upright. The other symptoms listed point to different issues: shortness of breath while standing would be a different pattern (platypnea), chest pain with exertion suggests angina, and palpitations are sensations of an irregular or rapid heartbeat.