Difficulty in breathing with heartburn in the back may be caused by pulmonary embolism, myocardial infarction and dorsal fasciitis. 1. Pulmonary embolism: when the human deep vein thrombus is dislodged, it will block the pulmonary artery and cause pulmonary embolism, and the patient will experience symptoms such as dyspnea and pain in the back of the undershirt. 2. Myocardial infarction: it is a common acute cardiovascular disease, mainly due to the occlusion of the main blood vessels of the heart’s blood flow and the interruption of blood, resulting in ischemic necrosis of the heart muscle, causing the patient to experience pain in the back of the undershirt, dyspnea and other symptoms. 3. Dorsal Fasciitis: Aseptic inflammation of the dorsal fascia caused by trauma or cold, resulting in symptoms such as restricted movement, pain in the undershirt, and dyspnea. When the patient has the symptoms of back pain and dyspnea, it is recommended to go to the hospital in time for examination and diagnosis, and under the guidance of the doctor for treatment.