When the heart contracts, the anterior wall of the left ventricle strikes the chest wall in the precordial region early in systole, causing the corresponding part of the rib question tissue to pulsate outward, called apical pulsation. After myocardial infarction of the left ventricle, the entire myocardium of the ventricular wall is necrotic. In about 10-38% of cases, the necrotic myocardium is gradually replaced by fibrous scar tissue, forming a ventricular wall tumor. The thin layer of the ventricular wall in the lesioned area bulges outward, and the heart loses mobility or shows paradoxical motion during contraction. The evolution of coronary artery obstruction, myocardial infarction, myocardial fibrosis, and left ventricular wall tumors was well understood as early as 1881. Ventricular wall tumors in the left ventricle cause loss of myocardial contractility in the lesioned area and can produce reverse beats. The ventricular wall tumor expands outward during ventricular systole and retracts during diastole, resulting in a decrease in left ventricular ejection volume. Normal myocardial contractility is enhanced, tension is increased, and myocardial oxygen demand is increased. When the ventricular wall tumor volume exceeds the left ventricular end-diastolic volume by more than 15%, the left ventricular end-diastolic pressure increases. Left ventricular failure is progressively worsened by the impairment of left ventricular blood displacement. Once the thrombus is dislodged from the ventricular wall tumor, embolism of the body circulation can occur. Cardiovascular angiography is the rapid injection of a contrast agent into the heart chambers or blood vessels through a cardiac catheter to visualize the heart and blood vessel cavities under x-ray irradiation. It is a valuable method to diagnose the heart and blood vessels. It is a valuable method for diagnosing cardiovascular disease. Cardiac angiography is a valuable method for diagnosing cardiovascular disease, as it allows the physiological and anatomical changes of the heart and blood vessels to be seen. 2.Electrocardiogram The heart is excited by the pacing point, atria and ventricles successively in each cardiac cycle, accompanied by bioelectrical changes, and the graph of various forms of potential changes elicited from the body surface through an electrocardiographic tracer is called electrocardiogram (ECG for short). ECG is an objective indicator of the process of occurrence, propagation and recovery of cardiac excitation. ECG is an important tool to help determine whether the electrical activity of the heart is normal, and is the earliest, most commonly used and most basic diagnostic method in the diagnosis of coronary heart disease. Electrocardiogram (ECG or EKG) examination can record from the body surface the graphical changes of electrical activity generated by each cardiac cycle of the heart, which has diagnostic significance for heart diseases.