Decreased tricuspid valve deformity
Introduction
Introduction to tricuspid valvular deformity The tricuspid valvular deformity is a rare congenital heart malformation. In 1866, Ebstein first reported an example, so it is also known as the Ebstein malformation. The incidence rate is 0.5-1% in congenital heart disease. The tricuspid valvular deformity refers to the tricuspid valve malformation. The posterior valve and septum are lower than normal, and are not moved to the right ventricle at the level of the atrioventricular ring. Near the apex of the wall, the position of the anterior lobes is normal, resulting in a larger right atrium, while the right ventricle is smaller than normal, and there may be tricuspid regurgitation. Such malformations often involve open or atrial septal defect and pulmonary stenosis. Because the blood volume in the right atrium is high and the pressure is increased, the blood contained in the right atrium flows into the left atrium through the atrial septal defect or the foramen ovale, and some of the blood still enters the right ventricle through the tricuspid valve. Due to pulmonary stenosis, the blood volume entering the pulmonary circulation is reduced. Therefore, the amount of arterial blood returning to the left atrium is also small. At this time, it is mixed with the venous blood from the right atrium, and enters the left ventricle and the systemic circulation through the mitral valve. basic knowledge The proportion of illness: the incidence rate of infants and young children is about 0.007%-0.01% Susceptible people: no specific population Mode of infection: non-infectious Complications: thrombosis Tricuspid regurgitation
Cause
Cause of tricuspid valvular deformity
Pathogenesis
The hemodynamic changes of the tricuspid valvular movement are determined by the severity of tricuspid regurgitation, whether there is an atrial septal defect and the size of the defect and the extent of right ventricular function, due to the atrioventricular and right ventricular enlargement and Different degrees of tricuspid regurgitation, such as leaflet deformation, are common. The right ventricle is dilated in the right atrium, and the diastolic enlargement of the ventricular portion causes the right atrial blood to fail to enter the right ventricle. The right atrium dilates and the right ventricle contracts. The right ventricle of the room is also contracted, so the right atrium receives blood from the vena cava, the atrialized right ventricle and the tricuspid regurgitation, resulting in increased blood volume in the right atrium, expanding the chamber and increasing the pressure on the right atrium. In patients with heart failure and patent foramen ovale or atrial septal defect, right-to-left shunt occurs when the right atrial pressure is higher than the left atrium, and the blood oxygen content of the systemic circulation decreases with purpura and clubbing (toe). When the room is intact, when the right ventricle contracts, the blood volume is reduced into the lungs, and the blood and oxygen difference between the arteries and veins becomes smaller, which can produce cheek flushing, and the fingertips are slightly purple. .
Prevention
Tricuspid valvular deformity prevention
About 80% of people with severe purpura after birth die at about 10 years of age, while only 5% of those with mild purpura die around 10 years old. After congestive heart failure in patients, most of them die within 2 years, and about 3% of cases are sudden death.
Common causes of death: congestive heart failure, arrhythmia, hypoxia or pulmonary infection. Adult patients often die from repeated embolism, with an average age of 20 years.
Complication
Tricuspid vertebral malformation complications Complications thrombosis tricuspid regurgitation
Tricuspid valvular surgery has the following risks and may cause complications:
(a) thrombosis
1. Reason: Folding and suturing the right ventricle, forming a part of the "pouch" after knotting, so that the blood stays and forms a blood clot. If mechanical valve replacement is performed, the thrombus is more likely to form.
2. Countermeasure: The operator is required to master the normal operation technique, the first double-needle with a small shim in the suture, the lowest point from the posterior lobes, the shallow needle in the right ventricle, and the two needles in the right After the heart chamber passes through the myocardium, after 4 to 5 consecutive sutures, the anterior inner side of the coronary sinus ostium (avoiding the Koch triangle) is approached to the normal annulus, and the two needles pass through the small gasket, and the needle is inserted into and out of the needle. The wall of the right ventricle cannot be penetrated, and the myocardial tissue must be hung. It is required to be firm and reliable. The needle spacing at the annulus should be greater than the needle spacing at the lowest point of attachment of the leaflet. After knotting, it can play a role in reducing the annulus. In the same way, 4 to 5 pairs of double-ended needle-type sutures are radially sewed, and the lines are tied tightly, which can eliminate the phenomenon of "bag".
If the artificial mechanical valve is used for tricuspid valve replacement, anticoagulation therapy must be performed after surgery.
(two) tricuspid regurgitation
1. Causes: Tricuspid dysplasia occurs in patients with tricuspid valvular dysplasia, and the insufficiency occurs due to the expansion of the valve leaflet and the annulus; the tricuspid annulus is still larger after simple folding, and the anterior leaflet Can not hold the mouth.
2. Countermeasures: If the above situation is required, segmental De Vega annuloplasty or annuloplasty should be performed, and the anterior and posterior leaf junctions should be sutured to reduce the annulus and other repairs, such as water injection test. If there is still significant insufficiency, tricuspid valve replacement should be performed decisively.
(C) problems in tricuspid valve replacement
The tricuspid valve is severely moved down, the anterior valve leaflet is thickened, the subvalvular structure is poorly developed, and the right ventricular ventricular stiffness is not suitable for folding. The tricuspid valve replacement is necessary. The surgical procedure is the same as conventional tricuspid valve replacement. The problem:
1. What type of prosthetic valve is placed; it is generally considered that the low-grade bovine pericardial valve is preferred, and only anticoagulant drugs should be taken for a short period of time. The chance of thrombosis is less. St. Jude double-leaf flap can also be used. Adults use 29~31 No. 25~27, children need antibiotics for life.
2. Where is the artificial flap: If the right ventricle and the annulus are large, foldable to reduce the part of the right ventricle, the suture will be sutured to the artificial valve, and the suture will be tightened.
3. Conduction block: Place the coronary sinus orifice in the right ventricle.
Symptom
Tricuspid valvular deformity Symptoms Common symptoms Palpation without pulmonary occlusion Closed ovate hole closed incomplete purpura atrophy Aortic and pulmonary arteries Small systolic murmur Atrial septal defect Pulmonary artery stenosis Tricuspid stenosis Cardioangiography See double-ball sign
(a) symptoms
A small number of patients can experience dyspnea, purpura and congestive heart failure within 1 week after birth, but most patients become ill-advanced after diarrhea, palpitations, cyanosis and heart failure, and can be used in all age groups. Supraventricular tachycardia is present, and some patients have pre-excitation syndrome.
(two) signs
Most patients have poor growth and development, and their body size is small. About 1/3 of the patients have cheek flushing similar to the mitral valve face. They often have different degrees of purpura. The case of enlarged heart is left anterior chest bulge, the heart sounds are widened, and the left sternal border can reach three. The systolic tremor caused by incomplete mitral regurgitation, the apex of the apex area and the apical area are normal or weakened. Because the right atrium and the right ventricle are enlarged, the jugular pulsation is not obvious. The heart is auscultated, the heart sound is light, and the left sternal border can be heard. The systolic murmur caused by tricuspid regurgitation, and sometimes the diastolic murmur caused by tricuspid stenosis, the increased acoustic intensity during inhalation, due to the increased delayed anterior tricuspid lobes, the first mitosis The delayed appearance of the component is enhanced, the second heart sound is often split and the pulmonary valve closing sound is lighter. In some cases, the galloping can be performed. The abdominal examination may cause swollen liver but rarely liver pulsation. In severe cases, the clubbing (toe) may appear.
Pathological change
The pathological changes of Ebstein malformation are quite different. The basic lesions are tricuspid valve leaflet and right ventricular dysplasia with the valvular and posterior lobes moving down to the right ventricle, attached to the tricuspid annulus by the chordae papillary muscle. On the lower right ventricular wall, the tricuspid valve leaf enlarges or shrinks, and the thickening and deformation are often shortened. The lesion most often involves the valvular leaflet, followed by the posterior leaflet, and the valvular and posterior leaflets may be partially missing. The anterior leaflet is rare. The anterior leaflet originates from the normal tricuspid annulus. It can be enlarged like a sail. Sometimes there are many small holes. The chordae and papillary muscles are attached to the ventricle through shortened and underdeveloped chordae. The wall, the downwardly moving leaflet divides the right ventricle into two parts. The enlarged ventricle above the leaflet is called the ventricular ventricle, and its function is similar to that of the right atrium. Below the leaflet is the function of the right ventricle, the right atrium is enlarged, and the wall fibers are The thickening of the right atrium and the highly enlarged thin-walled right ventricle connect the ventricle into a large heart chamber, which acts as a reservoir of blood, while the functional right ventricle below the leaflets acts to discharge the blood, and the tricuspid valve moves downward. Case due to the tricuspid annulus and right ventricular height expansion And leaflet malformations often appear to be incomplete, if the free edge of the valve leaf is partially adhered, the enlarged anterior leaflet can cause different degrees of tricuspid stenosis in the blood flow obstruction between the room ventricle and the functional right ventricle. The anatomy of the ventricular and atrioventricular bundles is normal, but the right bundle branch may be thickened by endocardial compression to produce a right bundle branch block. About 5% of the cases have abnormal Kent conduction bundles presenting pre-excitation syndrome, under the tricuspid valve About 50% to 60% of patients with vaginal foramen ovale or atrial septal defect, atrial level showed right to left shunt, arterial oxygen saturation decreased, clinically appeared purpura, other combined malformations still have pulmonary stenosis, ventricular septum Defect, patent ductus arteriosus, tetralogy of Fallot, aortic dislocation, aortic coarctation and congenital mitral stenosis.
Examine
Tricuspid valvular deformity examination
(1) Light examination cases can be free of cyanosis, middle and heavy cases have cyanosis, prone to supraventricular tachycardia, often with congestive right heart failure, physical examination in the tricuspid region with systolic reflux murmur, There is a third heart sound or a fourth heart rhythm.
(2) ECG shows right atrial hypertrophy, incomplete or complete right bundle branch block, often with pre-excitation syndrome.
(3) X-ray examination showed that the pulmonary blood was reduced or normal, the heart was spherical or elliptical, and the vascular pedicle was narrow.
(4) Echocardiography can be seen in the degree of tricuspid valve down and down, pay attention to tricuspid regurgitation, anterior valve development, presence or absence of atrial septal or patent foramen ovale.
(5) Right heart catheterization and contrast catheters are easy to pass through the open or closed fossa into the left atrium, and the pressure in the "trial ventricle" is the right atrial pressure waveform, while in the right heart chamber is the right ventricular pressure waveform. The angiography showed enlargement of the right atrium, atrialized right ventricle, an enlarged functional right ventricular outflow tract, and a descending tricuspid valve attachment.
(6) Electrophysiological examination diagnosis of tricuspid valvular deformity must be clearly classified, with or without pre-excitation syndrome, if there is pre-excitation syndrome, electrophysiological examination must be performed before surgery, and intraoperative electrophysiological mapping is prepared.
Diagnosis
Diagnosis and differentiation of tricuspid valvular deformity
diagnosis
Diagnosis can be performed based on clinical manifestations and examinations.
Differential diagnosis
The disease needs to be differentiated from other valvular diseases. The most important clinical identification is tricuspid dysplasia and tricuspid half-valve deficiency:
Most of the tricuspid valvular deformities are accompanied by a large number of tricuspid regurgitation, while other diseases such as tricuspid regurgitation, tricuspid prolapse, trauma, right ventricular dysplasia, endocarditis, tricuspid annulus expansion Can cause a large number of tricuspid regurgitation, but these diseases have their own characteristics, easy to identify, but tricuspid valve absent and tricuspid dysplasia and tricuspid valvular deformity have many similarities, need to be carefully identified, mainly The discriminating point is the absence of right ventricular dilatation rather than hypoplasia; the absence of leaflet morphology and flap effect in the right chamber is helpful for identification. This differential diagnosis is important for surgically determined surgical procedures, tricuspid dysplasia In some cases, the severely enlarged right atrium and the leaflet and right ventricular wall adhesions cause the illusion of the annulus or leaflet to move down, but the multiple sections carefully recognize the non-valve leaf down, the right ventricle is not narrow but expands and has no room. The contralateral movement of the right ventricle can be differentiated from the dislocation deformity. Most of the patients with X-ray examination showed less pulmonary blood, and the right atrium and right ventricle were significantly enlarged. A few patients had normal pulmonary blood and mild right heart, but the X-ray and X-ray The cardiac catheter can not show the leaflets, so for Ebste The diagnostic accuracy of in malformation is limited.
