What Is Tricuspid Atresia? Tricuspid atresia is the congenital absence of the tricuspid valve, which should be located between the right atrium and the right ventricle of the heart. In a normal heart, blood poor in oxygen passes from the right atrium to the right ventricle and is sent to the lungs. In tricuspid atresia, this passage is not possible. The blood has to continue its circulation through other openings in the heart. The right ventricle is usually underdeveloped. For this reason, the disease is considered among the congenital heart diseases with single ventricle physiology. What Is Single Ventricle Heart Disease? Single ventricle heart diseases are complex congenital heart anomalies in which only one of the heart's two ventricles can effectively support blood circulation. In addition to tricuspid atresia, this group includes hypoplastic left heart syndrome, double inlet left ventricle, and some complex heart anomalies. In these diseases, the aim is to regulate blood circulation as much as possible, reduce the load on the heart, and ensure that the body receives enough oxygen. Why Does Tricuspid Atresia Occur? Tricuspid atresia occurs during the baby's heart development in the womb. The exact cause of the disease is unknown in most cases. It may be associated with some genetic factors and other congenital heart anomalies. The disease may be seen together with different holes in the heart and abnormalities of the connections of the great vessels. What Are the Symptoms of Tricuspid Atresia? Symptoms vary according to the amount of blood going to the lungs and the accompanying heart anomalies. The most common symptoms are as follows: - Bluish discoloration of the lips and skin - Rapid breathing - Tiring quickly during feeding - Inadequate weight gain - Excessive sweating - Weakness and delayed growth - Serious low oxygen in severe cases While marked bluish discoloration is seen immediately after birth in some babies, signs of heart failure may be in the foreground in some patients. Important: Marked bluish discoloration, difficulty breathing, or serious weakness in a newborn requires urgent medical evaluation. How Is Tricuspid Atresia Diagnosed? Tricuspid atresia can be diagnosed in some babies during pregnancy by fetal echocardiography. After birth, a detailed evaluation is made by a pediatric cardiology specialist. The main methods used in diagnosis: 1. Echocardiography (ECHO) The structure of the heart, the absence of the tricuspid valve, the development of the ventricles, and blood flow are evaluated. 2. Oxygen Saturation Measurement The oxygen level in the blood is checked. 3. Electrocardiography (ECG) The electrical activity and rhythm of the heart are examined. 4. Cardiac MRI or CT Imaging It may be used for detailed evaluation of complex heart and vascular anatomy. 5. Cardiac Catheterization When necessary, pressures inside the heart, lung vascular resistance, and circulation characteristics are evaluated. Is Surgery Necessary in Tricuspid Atresia? Tricuspid atresia is not a disease that can resolve on its own. In most patients, surgical or catheter-based interventions are needed to rearrange blood circulation. The treatment plan is determined according to the following factors: - The baby's age and weight - The oxygen level in the blood - The amount of blood going to the lungs - The anatomical features of the heart - Accompanying heart anomalies - Lung vascular pressure and resistance Staged surgical treatment is generally applied. Surgical Treatment in Tricuspid Atresia and Single Ventricle Diseases The main aim of surgical treatment is to direct the oxygen-poor blood returning from the body to the lungs as directly as possible and to ensure that the functional ventricle pumps blood to the body. Treatment is mostly carried out in several stages. Stage 1: Initial Intervention in the Newborn Period The first surgical procedure is planned according to the baby's heart anatomy and lung blood flow. In babies who do not get enough blood to the lungs, a systemic-pulmonary shunt operation or suitable catheter interventions may be applied. In some babies who get excessive blood to the lungs, a pulmonary artery banding procedure may be needed. In some patients, surgical intervention may not be needed in the newborn period, and the baby can be followed closely until the next stage. Stage 2: Glenn Operation The Glenn operation is generally planned at 3–6 months of age. However, the timing may vary according to the patient's clinical condition. In this operation, the superior vena cava, which carries oxygen-poor blood from the upper part of the body, is connected directly to the pulmonary arteries. In this way, part of the blood reaches the lungs without passing through the heart. The aim of the Glenn operation is to reduce the volume load on the functional ventricle and to prepare the circulation for the next surgical stage. Stage 3: Fontan Operation The Fontan operation is generally performed at around 2–4 years of age. The appropriate timing is determined according to the child's development and heart and vascular features. In this operation, the venous blood coming from the lower part of the body is also directed straight to the pulmonary arteries. In this way, most of the oxygen-poor blood reaches the lungs without passing through the heart's pumping chamber. The Fontan operation does not make the heart anatomically normal; it rearranges the single ventricle circulation. Can Glenn and Fontan Operations Be Applied to Every Child? Not every single ventricle patient may be suitable for a Glenn or Fontan operation. When evaluating surgical suitability, the following are taken into account: - Lung vascular pressure and resistance - The pumping strength of the functional ventricle - The condition of the heart valves - The development of the pulmonary arteries - Heart rhythm and general circulation characteristics For the Fontan circulation to be successful in particular, it is important that lung vascular resistance is low and heart function is adequate. Are Tricuspid Atresia Operations Risky? Operations performed in tricuspid atresia and single ventricle diseases are among the complex operations of pediatric heart surgery. Surgical risks vary according to the patient's anatomy, general health condition, and the type of operation performed. Possible complications include: - Bleeding and infection - Heart rhythm disorders - Impairment of heart function - Clot formation - Fluid accumulation in the lungs or chest cavity - Circulation and oxygenation problems - The need for additional surgery or a catheter intervention The Recovery Process After Surgery After surgery, children are followed in the pediatric heart surgery intensive care unit. During this process, heart function, oxygen level, breathing, and circulation are closely monitored. In addition: - Feeding and weight gain are evaluated. - Heart rhythm is checked. - Necessary medication treatments are arranged. - The function of the vascular connections is examined. - The next treatment stages are planned. The recovery time may vary according to the child's general health condition and the scope of the operation. Can Children with Tricuspid Atresia Live Normally? After successful staged surgical treatment, many children can grow, continue their education, and carry on their daily activities. However, the Fontan circulation is different from the normal two-ventricle heart circulation. In later years, complications such as heart rhythm disorders, reduced exercise capacity, liver problems, protein-losing enteropathy, and deterioration of heart function may develop. In some patients, a heart transplant may be needed in later periods. For this reason, children with single ventricle heart disease need to be followed for life by specialist cardiology teams. Why Are Early Diagnosis and Correct Surgical Planning Important? Tricuspid atresia is a serious heart disease that can affect blood circulation from birth. Diagnosis during pregnancy or immediately after birth allows the baby to be followed and treated at a suitable center. The coordinated work of pediatric cardiology, pediatric heart surgery, and neonatal intensive care teams plays an important role in the treatment process. Remember: Tricuspid atresia and single ventricle heart diseases are serious congenital anomalies that mostly require staged surgical treatment. Early diagnosis, operations performed at the right time, and lifelong cardiological follow-up are of great importance in increasing children's life expectancy and quality of life.