Coronary artery theft, also called coronary artery theft, refers to the narrowing of a branch of the coronary artery, and in order to meet the demand of the body’s blood supply, compensatory dilation of the distal vessels occurs as a power reserve, giving itself a certain regulatory role to ensure normal blood flow. At this time, if the patient is given strong vasodilator drugs, after increasing the exercise load, the stimulation will cause the normal coronary artery branches to play a significant dilatation, increasing blood flow, leading to the development of atherosclerosis. Distal resistance vessels due to maximum dilation, blood flow in the ischemic area will not be increased by the application of drugs, and the resistance of the vessels in the non-ischemic area will be given to the ischemic area, so the patient will have the clinical symptom that the distal myocardial blood flow seems to be stolen, so it is called coronary artery theft.