A slow heart rate does not usually cause chest tightness and shortness of breath. The normal range for heart rate is 60 to 100 beats per minute. If it is lower than 60 beats per minute, it is considered a slow heart rate and is clinically known as bradycardia. It may cause insufficient blood supply to the brain, producing symptoms of dizziness, headache, blurred vision and even fainting. Common causes of chest tightness and shortness of breath include respiratory diseases or cardiac insufficiency. 1. Respiratory diseases: Chronic obstructive pulmonary disease (COPD), bronchitis, lung infections and pneumothorax usually block the airway and cause symptoms of chest tightness and shortness of breath. 2. Existence of cardiac insufficiency: Suffering from coronary heart disease, dilated heart disease, high blood pressure and other diseases usually suggests the existence of cardiac insufficiency, usually with symptoms of chest tightness and shortness of breath. Slow heart rate and chest tightness and shortness of breath and does not relieve the person should immediately stop the activity, timely medical care, under the guidance of the doctor to identify the causes of active treatment, so as not to delay the condition, delay the best time for treatment.