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 ventricular wall tumors was well understood as early as 1881. Differential diagnosis of reverse beats due to double outlet of the left ventricle: 1. Double outlet of the right ventricle Unlike the double outlet of the left ventricle, the double outlet of the right ventricle is where both the aorta and the pulmonary artery originate in the right ventricle, or where one large artery and most of the other large artery originate in the right ventricle, with the septal defect being the only outlet of the left ventricle. The ventricular septal defect is usually larger than the caliber of the aorta, and in only 10% of cases is the caliber of the ventricular septal defect smaller than the aortic opening, and about 60% of ventricular septal defects are located below the aortic valve and 30% below the pulmonary valve. The ventricular septal defect is located in the middle and lower part of the ventricular septum and the aortic opening. 2. Complete transposition of the great arteries The anatomical characteristics of this defect are that the atria and ventricles are connected in the same order, but the ventricles and great arteries are not connected in the same order, i.e. the aorta starts from the right ventricle and the pulmonary artery starts from the left ventricle, and if there is no other malformation of the heart and great vessels, the two main body-pulmonary circulations are not connected to each other, and the child cannot survive after birth. Cardiac catheterization and cardiovascular angiography can be used to differentiate. The pathological and anatomical features of corrective transposition of the great arteries are the inconsistent connection between the normal anatomical atria and the ventricles, i.e., the orthotopic right atrium is connected to the anatomical left ventricle through the mitral valve and to the pulmonary artery, while the left atrium is connected to the anatomical right ventricle through the tricuspid valve and to the aorta. If no other cardiac anomalies are combined, the hemodynamics are naturally corrected, the patient has no clinical symptoms or pathological signs, and no surgical management is required. However, corrected aortic malposition often has combined malformations: (1) ventricular septal defect (VSD), accounting for about 4/5 of cases, mostly subpulmonary trunk VSD, followed by membranous VSD; (2) pulmonary stenosis (PS), accounting for about 50% of cases, PS is mostly a thickened and fused pulmonary valve, annular stenosis and subvalvular stenosis are also more common; (3) atrial septal defect (ASD), accounting for about 20% of cases, mostly secondary to foramen ovale ASD. Sometimes the foramen ovale is not closed; ④ Other: patent ductus arteriosus (PDA), left atrioventricular valve closure insufficiency, aortic constriction, etc.