Patients with chest tightness, shortness of breath, and weakness of the extremities should consider the following points: First, ionic disorders should be considered. Patients with hypokalemia are commonly seen to have obvious clinical symptoms as described above. Second, in addition, for endocrine metabolic diseases, often in hypothyroidism, hypoparathyroidism, and adrenocortical insufficiency, the above-mentioned situation will also occur. Third, if the patient has cardiogenic diseases, such as unstable angina pectoris, heart failure, arrhythmia, the patient will have the above clinical symptoms. Fourth, severe myocarditis, cardiomyopathy, will also lead to the above situation. However, it is usually accompanied by a rise in body temperature at this time.