One of the rare heart defects is Ebstein's anomaly. This is a congenital disease in which the tricuspid valve of the heart is moved to the right ventricle, although it should be on the border between the ventricle and the atrium. It is located much lower in the blood flow.
Anatomical features
Ebstein’s anomaly leads to the fact that the cavity of the right ventricle becomes smaller, and the right atrium is more than normal.
Valve flaps are also different. They may be improperly developed or displaced. The development of the entire chordal and muscular apparatus, which sets in motion the tricuspid apparatus, is disrupted.
Due to the small size of the right ventricle, less blood is ejected from it. And the increased size of the right atrium is due to the fact that part of the venous blood enters it.
Many patients with Ebstein's abnormality are also diagnosed with an atrial septal defect and an open oval window. This concomitant vice is life-saving for many. Through a septal defect from a crowded right atrium, blood is discharged. True, in this case, venous blood in the left atrium is mixed with arterial. This causes oxygen starvation of tissues and organs.
Causes of the disease
Less than 1% of people with congenital heart defects are diagnosed with Ebstein's anomaly. The reasons for its development could not be precisely determined. According to assumptions, it appears due to genetic abnormalities. Also, according to one version, the use of drugs containing lithium salts during pregnancy can lead to such a development of the heart muscle.
This congenital disease is accompanied in 50% of cases by an atrial septal defect. In other cases, rhythm disturbance is noted. Doctors have not yet been able to understand why certain combinations of heart defects occur.
Possible options for the course of the disease
Ebstein's anomaly is a critical congenital heart disease. It is found in both boys and girls. The course of the disease and prognosis will depend on the degree of deformity of the tricuspid valve. Pathophysiological changes that have occurred in the right atrium and ventricle are also important.
In some cases, the defect significantly disrupts the blood circulation of the fetus. Heart failure occurs, dropsy develops, and in 27% of cases, intrauterine death of the child occurs. With a deep pathology after birth, babies die during the first month of life. According to statistics, this is about 25% of all children whose Ebstein anomaly was detected. The diagnosis during pregnancy can be made at the 20th week.
About 68% of newborns with this pathology survive to six months, and up to 5 years - 64% of children. This group includes babies in whom the function of the tricuspid valve and the right ventricle is satisfactory. In most cases, they die from progressive heart failure and rhythm disturbances.
Classification of types of disease
Specialists distinguish several stages of the disease, known as Ebstein's anomaly. Symptoms will depend on how bad the heart is. The most rare is the asymptomatic stage. Such patients may not even be aware of the pathology and lead a normal lifestyle. They tolerate physical activity well.
In the second stage, clinical manifestations are pronounced. This anomaly manifests itself in childhood and is quite difficult. Separately, the stages are distinguished:
- II a - it is characterized by the absence of cardiac arrhythmias;
- II b - seizures are common.
The third stage is called the period of persistent decompensation. It is diagnosed in cases where the body is not able to compensate for the activity of the heart by any auxiliary mechanisms.
The clinical picture of the disease
At birth, children with Ebstein's anomaly are cyanotic. Cyanosis after 2-3 months of life is reduced due to the fact that the resistance of the vessels of the lungs decreases. But in children with a slight defect in the septum, the risk of death from complications of cyanosis and progressive heart failure increases.
In children with Ebstein's anomaly, the following symptoms are often observed:
- shortness of breath even during rest;
- swelling that is visible on the lower extremities;
- increased fatigue, especially noticeable during physical exertion;
- heart rhythm disturbances;
- cyanosis of the skin and lips.
Cyanosis appears in children earlier than symptoms of heart failure. Older children may complain of periodic bouts of palpitations.
Diagnosis of the disease
In some cases, the disease is determined during pregnancy or immediately after birth in the hospital. There are several characteristic signs by which the doctor may suspect that the child has an Ebstein anomaly. Diagnosis includes auscultation, chest x-ray, echocardiography, ECG. All these methods in combination allow you to accurately establish the diagnosis.
When auscultation, the doctor can hear a characteristic rhythm, it can be three or four times. It drowns out the high-frequency silent systolic murmur of tricuspid insufficiency. In addition, the splitting of the second tone is pronounced, it does not change when breathing. At the top of the left edge of the sternum, a mesodiastolic creaky quiet noise should be heard.
On radiography, an expanded heart shadow is visualized, this is due to a significant increase in the right atrium. The vascular pattern of the lungs is usually pale. The heart often takes the shape of a ball.
Changes are observed on the ECG. The cardiogram shows signs of hypertrophy of the right atrium, the PQ interval is lengthened, and a complete or partial blockade of the right bundle branch block is observed .
On the echocardiography you can see the wide opening of the tricuspid valve. The septum is biased towards the apex.
Tactics for Congenital Anomaly
After diagnosis and determining the degree of damage, treatment is selected. Of course, such patients need surgical intervention. The exception is only that small group of patients who have asymptomatic Ebstein anomaly.
Treatment is carried out depending on other concomitant problems. If the patient normally survived the infant age, then the operation can be postponed until pronounced symptoms of heart failure appear.
All babies with this problem should be observed by a pediatric cardiologist who specializes in congenital heart defects. Also, his condition should be monitored by cardiac surgeons.
If patients have a pronounced decrease in pulmonary blood flow and signs of heart failure are observed, then infusions of ionotropic drugs and prostaglandins of group E are prescribed. Correction of metabolic acidosis is also indicated. This treatment allows you to increase cardiac output and reduce compression of the left ventricle by the expanded right side.
In cases where tachycardia is observed, it is necessary to carry out therapy with special antiarrhythmic drugs.
Indications for surgery
During
the neonatal period, they try not to do the operation. But it is necessary in cases where the right ventricular dysplasia is pronounced and is accompanied by impaired antegrade blood flow to the pulmonary bed. In this case, there is a sharp expansion of the right departments and simultaneous compression of the left ventricle.
Relative contraindications include age up to 4-5 years. But if necessary, they also perform an operation for the newborn. Also, surgery is not performed for those who have begun to have organic irreversible changes in their internal organs.
Patients in whom Ebstein's anomaly was discovered can survive on average up to 20 years without surgery. Their death, as a rule, is sudden. It occurs due to fibrillation of the ventricles of the heart.
Operation
Only with the help of surgical intervention can completely correct the situation. At the same time, doctors recommend, if possible, to do it at an older age due to too small heart sizes in infancy.
The operation is performed on an open heart, to realize the possibility of its implementation, they organize the process of cardiopulmonary bypass. The excess part of the right atrium is sutured, and the tricuspid valve sutures rises to a position that is close to normal. In cases where this is not possible, it is removed and replaced with a prosthesis. This allows you to forget that the patient had an Ebstein anomaly. In adult patients, prosthetics are possible, but for children under 15 years of age, valve surgery is performed.
Mortality during operations does not exceed 2-5%. The likelihood of death depends on the experience of the cardiac surgeon, and on the severity of the defect. In almost 90% of cases, patients can return to their normal lifestyle within a year.
Particular attention should be paid to such patients by anesthetists. After all, a special approach is required for patients who have an Ebstein anomaly. Features of anesthesia should be known to the doctor. He must take into account that the pressure in such patients can be unstable. Therefore, the anesthetist observes his patients after the operation.
Types of prostheses
In most cases, it is possible to decide how the operation will be carried out only when the patient is already on the operating table. If it is possible to carry out valve plastic surgery, then this option is preferred. But there are situations when a prosthesis is necessary for patients who have an Ebstein anomaly. This is the name of the artificial valve, which looks like a ring covered with a synthetic pillow. Inside it is a mechanism that can open and close the so-called gateway. It can be mechanical or biological. The first option is made of a titanium alloy, and the second can be made from a pig valve or from tissue of a human heart shirt.
When installing a mechanical valve, the patient must constantly drink blood-thinning medications, but if the regimen is followed, it can function longer. The biological device is less durable.