A low partial thromboplastin time indicates that the blood is in a hypercoagulable state, when thrombotic disorders, such as cerebral infarction and lower extremity thrombosis, are likely to occur. Partial thromboplastin time, or APTT, is a very important item in blood coagulation testing and is mainly used to detect whether the endogenous coagulation pathway is functioning normally. Under normal circumstances, the partial thromboplastin time is 31-43 seconds, if the test value is low, it indicates that the blood is in a hypercoagulable state. Patients who also have hypertension, coronary artery disease and diabetes should be alert to thrombotic diseases, which can easily induce lower limb venous thrombosis, cerebral infarction and acute myocardial infarction. Patients should take anticoagulant drugs such as aspirin and low molecular heparin under the guidance of doctors to stop blood clotting in time. Patients with combined high-risk factors are advised to quit smoking in time, avoid staying up late and straining, as well as avoiding overly oily and spicy stimulating foods, and visit the hematology department of the hospital as early as possible.