The absence of pulmonary artery closure on palpation is the clinical manifestation of Ebstein syndrome. Ebstein syndrome, also known as Ebstein malformation, is a condition in which the tricuspid septal and/or posterior valves occasionally attach to the right ventricular wall near the apex along with the anterior valve downward about 0,5% to 1,0% of the time in precordial disease. This is a rare disease, first reported by Ebstein in 1866. This disease is also known as tricuspid inferior valve malformation. Occasionally, there is a family history, and offspring of mothers taking lithium early in pregnancy are susceptible to this disease. In the functional right ventricle, systolic pressure may be normal, while diastolic pressure is often increased, similar to constrictive pericarditis. Both systolic and diastolic pressures are elevated in the atrial chambers. There may be a systolic pressure difference on both sides of the pulmonary valve and a diastolic pressure difference on both sides of the tricuspid valve. The former may be due to an overgrown tricuspid leaflet that partially obstructs the right ventricular outflow tract; the latter is due to a tricuspid valve malformation with narrowing of the tricuspid orifice. The following tests are required for palpation without pulmonary artery closure: 1. ECG: P-wave amplitude is increased and/or widened, and sometimes the tangents are most clearly seen in leads II and III, aVF, and V1. The P-R interval is often prolonged in almost every patient with complete or incomplete right bundle branch block. Low voltage is often present in the limb leads and right thoracic leads. QRS wave groups in leads Vl-4 are Qr-shaped with T-wave inversion, a specific ECG change for this malformation. Pre-excitation syndrome (type B) is found in about 5% to 25% of patients with this malformation. Of those with congenital heart disease combined with preexcitation syndrome, 30% have Ebstein malformation. Therefore, in clinical practice, Ebstein’s anomaly should be suspected when congenital heart disease is combined with prodromal syndrome. This malformation can occur in various arrhythmias, among which paroxysmal supraventricular tachycardia is common, even without preexcitation syndrome. Other arrhythmias such as atrial precontraction, atrial flutter or atrial fibrillation can be seen. 2.X-ray examination: In mild malformation, the heart enlargement is not obvious and the pulmonary blood is normal. In moderate and severe malformations, the heart is enlarged on both sides, mainly the right atrium is enlarged. The pulsation of the heart edge is not obvious under fluoroscopy, which is very disproportionate to the enlarged heart, similar to the X-ray signs of pericardial effusion or pulmonary artery stenosis with heart failure. Due to the enlargement of the right atrium combined with the leftward displacement of the right ventricular outflow tract, the cardiac shadow may be square box or funnel shaped, and a few lesions may be spherical. The pulmonary blood is reduced and the aortic node is normal or small. 3. Echocardiography: The most typical manifestation is an increase in the amplitude of the anterior tricuspid valve leaflet activity along with delayed closure (at least 0.04 s after mitral valve closure). In addition, if the probe is placed at the site that normally shows the right ventricle, a large cavity (atrialized right ventricle) is seen, and a slowing of the EF slope (early diastolic closing motion) of the tricuspid valve can be seen. 4, right heart catheterization: Previously, it was thought that Ebstein’s syndrome was extremely dangerous for cardiac catheterization, prone to serious arrhythmias and even life-threatening. Therefore, if cardiac correction is not considered, it is best not to perform this test. Now it is believed that if the clinical diagnosis is unknown, it should be performed despite the risk. With experienced personnel and resuscitation equipment, the risk is not significant. In an international cooperative study of 505 patients with this malformation, 363 catheterizations and angiograms were performed, and 100 arrhythmias occurred, including 13 deaths. The catheter is often coiled within the enlarged right atrium during right heart catheterization. Manipulation of the catheter often allows the catheter tip to be delivered into the left atrium (through interatrial traffic), but it is difficult to enter the right ventricle. The pressure in the right atrium is high, and the right atrial pressure curve shows increased a- and v-waves. The diastolic pressure in the right ventricle is high and the systolic pressure is normal or slightly high. Normal or low pulmonary artery pressure When the catheter is pumped back from the pulmonary artery to the right ventricle, or from the right ventricle to the right atrium, and the pressure curve is continuously recorded, a systolic pressure difference on both sides of the pulmonary valve and a diastolic pressure difference on both sides of the tricuspid valve can be found. In most patients, there is a right-to-left shunt at the atrial level, and occasionally a left-to-right shunt may be found at that level. In particular, if the pressure curve and intracardiac ECG are recorded simultaneously, a shifted zone between the right atrium and the functional right ventricle is often found. The pressure recorded in this zone is the same as that of the right atrium and the intracavitary ECG pattern is the same as that of the right ventricle. This shifted zone is the atrialized right ventricle. This finding is often helpful in the diagnosis of Ebstein’s syndrome. 5. Selective right heart system imaging: The main basis for the diagnosis of this malformation is: tricuspid valve malformation, inferior migration and atrialization of the right ventricle are usually seen in the inferior margin of the right atrium. In addition, selective right atrial angiography may reveal a markedly dilated right atrium with slow passage of contrast; early visualization of the left atrium, left ventricle, and aorta (when there is interatrial traffic). Selective right ventriculography may also reveal tricuspid regurgitation and narrowing or dilatation of the right ventricular outflow tract.