The first choice for diagnosing heart failure is to have a cardiac ultrasound, which is a non-invasive test that can be easily completed in an outpatient clinic, and in addition to this, the first choice is to have a blood test to check the level of atrial natriuretic peptide, which is elevated to reflect left heart failure, and if the atrial natriuretic peptide is normal, the shortness of breath should be considered for any factor of decreased lung function. In cardiac ultrasound, if the structure of the heart and ventricles are normal, the contraction is strong, and the ejection fraction is normal, the patient should consider whether there are other factors for shortness of breath, and the factors to be excluded are pulmonary factors, such as chronic obstructive pulmonary disease, chronic bronchitis, and asthma, which can cause shortness of breath. It is also necessary to determine whether the patient has heart failure, whether it is left or right heart failure, based on whether the patient’s signs are telangiectatic breathing, exertional dyspnea, edema, etc.