The normal blood pressure pulse pressure difference value is in the range of 30-40 mmHg, and if it is greater than 60 mmHg, the pulse pressure difference is considered to be increased. If the pulse pressure difference <20mmHg, the pulse pressure difference is considered to be reduced. The pulse pressure difference, which is the value of systolic pressure minus diastolic pressure, is called the pulse pressure difference. If a patient has an increased pulse pressure difference, consider the possibility that the patient has hyperthyroidism, aortic sclerosis or rheumatic heart disease, or aortic valve insufficiency. And if a patient has a decreased pulse pressure difference, consider that the patient may be prone to a decreased pulse pressure difference due to the presence of pericardial effusion, aortic stenosis, heart failure, and hypotension. For people with an abnormal pulse pressure difference, if the cause is not ultimately clear and the patient has no uncomfortable symptoms, the patient is reviewed regularly.