The length of survival of patients with symptomatic tricuspid atresia is closely related to pulmonary blood flow. Keith et al. reported that 50% of patients with tricuspid atresia survived to 6 months, 33% survived to 1 year, and only 10% survived to 10 years. Cases with small atrial septal access present clinically with venous congestion in the body circulation, jugular venous anger, hepatomegaly and peripheral-type edema. Due to the low pulmonary blood flow, most cases present with cyanosis from the neonatal period, shortness of breath after exertion, squatting position or hypoxic syncope. pestle-like fingers (toes) are often seen in patients over 2 years of age. In cases with increased pulmonary blood flow, cyanosis is reduced, but there is often shortness of breath, rapid breathing, and susceptibility to pulmonary infections, often presenting with congestive heart failure. What are the causes of little pulmonary blood flow: Tricuspid valve subluxation malformation: is a rare congenital heart malformation, Ebstein first reported a case in 1866, so it is also called Ebstein malformation. Its incidence in congenital heart disease accounts for 0.5% to 1%, tricuspid valve downshift malformation refers to the tricuspid valve displaced to the right ventricle, mainly septal and posterior valve leaflets downshift, often attached to the right ventricular wall near the apex rather than the fibrous ring part of the tricuspid valve, the location of the anterior valve leaflets more normal, so the right ventricle is divided into two cavities, the wall of the ventricular cavity above the malformed valve is thin, and the right atrium is connected to a large heart cavity, is for The chamber above the malformed valve has thin walls and is connected to the right atrium to form a large chamber, which is the “atrialized right ventricle” and has the same function as the right atrium; the chamber below the malformed valve, including the apex and outflow tract, is the “functional right ventricle” and plays the same role as the right ventricle, but the chamber is relatively small. It is often associated with an atrial septal defect, ventricular septal defect, patent ductus arteriosus, and pulmonary artery stenosis or atresia. Increased right atrial pressure may occur, which can lead to right-to-left shunting and cyanosis if there is an atrial septal defect or an open foramen ovale. Tricuspid atresia: It is a type of cyanotic congenital heart disease, with an incidence of 1% to 5% of congenital heart disease. It ranks third after tetralogy of Fallot and transposition of the great arteries in cyanotic congenital heart disease. It is defined by tricuspid and tricuspid orifice defects without direct communication between the right atrium and the right ventricle. The main pathological changes are tricuspid atresia or absence of the tricuspid orifice, unclosed foramen ovale or atrial septal defect, enlarged left ventricle, and hypoplastic right ventricle. The endocardial cushions fuse under normal development of the embryo, dividing the atrioventricular canal equally between the right and left orifices and participating in the formation of the membranous ventricular septum and closure of the foramen ovale 1 of the atrial septum. It is generally believed that the endocardial cushions fuse to the right before and after embryonic development, resulting in a rightward shift of the ventricular septum causing unequal separation of the atrioventricular orifices and later formation of tricuspid atresia if the right atrioventricular canal orifice is occluded. This malformation is essentially a specific type of left ventricular double inlet with only the left mitral valve between the left atrium and the left ventricle, left ventricular hypertrophy and mitral valve enlargement, and right ventricular hypoplasia. The majority of cases have atrial orthostasis and right ventricular collaterals, combined with atrial septal defect or patent foramen ovale and ventricular septal defect. Only a few cases have atrial antegrade and left ventricular collaterals. The relationship between the ventricles and the great arteries may be consistent or inconsistent, and the pulmonary arteries may be narrowed, atretic, or normal.