Radiation is an objective thing that does not depend on human will, in the environment we live on, radiation is everywhere, the sun emits light and heat generated by nuclear reactions, which is necessary for human survival, natural radioactive substances are widely distributed throughout the environment, even the human body also exists 14C, 40K, 210Po and other radionuclides, all life on earth is in such a radiation background All life on earth evolved under such a radiation background. But it is known that receiving too much radiation is harmful to the human body, so what dose of radiation is too much? Studies from the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) show that the annual per capita radiation dose in the natural state is about 2.8 mSv (millisieverts) worldwide. About 85% of it comes from natural sources (such as indoor radon decay products, cosmic rays, etc.), medical exposures (X-rays for diagnosis and treatment, γ-rays for nuclear medicine) account for about 14%, while other artificial sources, such as radioactive dust and nuclear industry emissions, account for less than 1%. The International Commission on Radiological Protection (ICRP) defines 100mSv as the safety threshold for personal low-dose radiation, meaning that an individual receiving a single dose of 100mSv of radiation, the probability of its possible harmful effects on the human body is 1%, if at this dose are considered to be basically safe, more than 100mSv, is considered to be excessive radiation. The following are some common radiation dose data: 1. the global annual per capita radiation dose in the natural state is about 2.8mSv; 2. a chest X-ray radiation dose of about 0.02mSv (equivalent to about 10 days of natural environmental radiation); 3. a flight radiation dose of about 0.1 to 0.5mS (equivalent to 5-20 chest films); 4. a coronary CT examination Radiation dose for one coronary CT examination is about 5 mSv; 5. Radiation dose for one coronary intervention (stent implantation) is about 10-30 mSv; 6. Radiation dose for one radiofrequency ablation of arrhythmia is 1-5 mSv; 7. The average radiation dose for a percutaneous fluoroscopic occlusion of arteriovenous ductus arteriosus was 0.31 mSv (equivalent to an airplane ride only); 9. The average radiation dose for a percutaneous fluoroscopic occlusion of ventricular septal defect was 0.37 mSv (equivalent to an airplane ride only). From the above data we found that the X-ray radiation dose in the interventional treatment of precardiac disease is considered very low among various cardiovascular interventions, which is much lower than the safety threshold and close to the amount of radiation received in normal production activities, and there are no reports of serious X-ray radiation damage in the literature on interventional treatment of precardiac disease at home and abroad, so the radiation dose in the interventional treatment of precardiac disease is relatively low and meets the relevant national industry and Therefore, the radiation dose in precordial interventions is relatively low and meets the safety standards of the relevant national industry and clinical care, and is completely acceptable relative to the clinical benefits (risk/benefit ratio) of patients.