Sleeping flat at night, feeling chest tightness and breathing difficulties. What's going on?

Chest tightness and dyspnea when lying flat at night are mainly considered as symptoms caused by asthma, especially obvious chest tightness symptoms at night; secondly, symptoms caused by insufficient blood supply to the heart or cardiac insufficiency are also considered. If this symptom occurs for a long time, it is suggested to go to the hospital for further examination.