Hello, Esophageal spasms are painful abnormal muscle contractions that occur in the lower esophagus. You need to get yourself assessed by a physician whether you have an esophageal spasm or something else. Since you don t have any pain associated with the episodes, I doubt that you are having esophageal spasms. You are having sudden episodes of breathlessness while sleeping which points towards a diagnosis of paroxysmal nocturnal dyspnea. I would advise you to get yourself checked by a physician for proper diagnosis and further course of action. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Nazma.amman