Non-ST-segment elevation myocardial infarction is usually more serious and requires attention and preventive treatment, which may be complicated by bleeding, arrhythmia, heart failure and other life-threatening conditions. 1. Bleeding: As the disease requires long-term treatment with anticoagulant drugs such as warfarin and rivaroxaban, side effects of the drugs may cause gastrointestinal bleeding and other discomforts, which requires timely consultation and monitoring of coagulation function during the drug taking period. 2. Arrhythmia: this disease is caused by myocardial ischemia and necrosis, which may change the calcium channels, membrane potential and electrophysiological characteristics of cardiomyocytes, resulting in various types of arrhythmia, such as ventricular arrhythmia, supraventricular arrhythmia, bradyarrhythmia, etc. When the arrhythmia continues to attack and aggravate, it may lead to sudden death. 3. Heart failure: it is usually the most common and highly lethal complication, which usually leads to the aggravation of pulmonary stasis, which may cause total heart failure and other discomforts, and in severe cases, it may also lead to myocardial ischemia and hypoxia, which may threaten the safety of life. When the above symptoms occur, it is recommended to go to the hospital in a timely manner, according to the doctor’s advice to carry out standardized treatment as soon as possible.