The tetralogy of Fallot consists of 4 factors: a large ventricular septal defect, a closure of the outflow tract of the right ventricle and the pulmonary valve, a right ventricular hypertrophy and an astride aorta. The symptoms include cyanosis, respiratory distress during feeding, low growth and hyperzianotische seizures (sudden, potentially fatal episodes of severe cyanosis) a. A harsh systolic murmur is heard over the left upper sternal border, a single second heart sound (S2) is frequent. The diagnosis is made by echocardiography. A cardiac catheterization may be required. The final treatment is surgical.
The tetralogy of Fallot (tetralogy of Fallot) accounts for 7-10% of congenital heart defects. Associated therewith malformations include the right aortic arch (25%), a pathological anatomy of the coronary arteries (5%), a stenosis of the pulmonary arteries, the presence of additional aortopulmonary vessels, a patent ductus arteriosus, a video channel, an atrial septal defect, additional ventricular septal defects ( VSD) and aortic regurgitation.
The tetralogy of Fallot consists of 4 factors: a large ventricular septal defect, a closure of the outflow tract of the right ventricle and the pulmonary valve, a right ventricular hypertrophy and an astride aorta. The symptoms include cyanosis, respiratory distress during feeding, low growth and hyperzianotische seizures (sudden, potentially fatal episodes of severe cyanosis) a. A harsh systolic murmur is heard over the left upper sternal border, a single second heart sound (S2) is frequent. The diagnosis is made by echocardiography. A cardiac catheterization may be required. The final treatment is surgical. The tetralogy of Fallot (tetralogy of Fallot) accounts for 7-10% of congenital heart defects. Associated therewith malformations include the right aortic arch (25%), a pathological anatomy of the coronary arteries (5%), a stenosis of the pulmonary arteries, the presence of additional aortopulmonary vessels, a patent ductus arteriosus, a video channel, an atrial septal defect, additional ventricular septal defects ( VSD) and aortic regurgitation. Tetralogy of Fallot The pulmonary blood flow is reduced, the RV hypertrophy and unoxygeniertes blood flows in the AO. The systolic pressure in RV, LV and AO are identical. The degree of arterial desaturation depends on the severity of the RV outflow tract obstruction. Right ventricular pressures are medium pressures. AO = aorta; IVC = inferior vena cava; LA = left atrium; LV = Left ventricle; PA = pulmonary artery; PV = pulmonary veins; RA = right atrium; RV = right ventricle; SVC = superior vena cava. The pathophysiology ventricular septal defect (VSD) is normally very large, thereby the systolic pressures in the right and left ventricles and the aorta are the same. The pathophysiology depends on the degree of obstruction of the right outflow tract. A small obstruction may cause a network-left-right shunt through the VSD, a severe obstruction causing a right-left shunt with low systemic arterial oxygen saturation that does not respond to an O2 supplementation. In some children with unrepaired tetralogy of Fallot, mostly in those that are several months to 2 years old, sudden episodes of severe cyanosis and hypoxia can (seizures) occur which can be fatal. Such attack may be by any event that the O2 saturation decreased (z. B. crying, defecation), or a sudden drop in the systemic peripheral resistance (such. As games pushing with the feet when waking up) is generated or during sudden occurrence a tachycardia or be triggered with hypovolemia. The mechanism of seizures is still unclear, but several factors are likely to be important for a rise in right-left shunts and a decrease in arterial saturation. The factors include an increase in the right ventricular outflow tract obstruction, an increase in the pulmonary vascular resistance and / or a decrease in the systemic resistance – a vicious circle, caused by the initial decline in arterial pO2, which stimulates the respiratory center and causes a hyperpnoea and increased adrenergic tonus. The increased circulating catecholamines then stimulate an increased contractility, which increased the outflow tract obstruction. Symptoms and complaints newborns with a high degree of obstruction of the outflow from the right ventricle (or atresia) show a severe cyanosis, respiratory distress during feeding and low weight gain. Newborns with low obstruction have at rest but may no cyanosis. Cyanotic attacks are triggered by activity and are characterized by a seizure-like increase in respiration (fast and deep breaths), irritability and prolonged crying, increasing cyanosis and quieter nascent heart murmur. The attacks usually come before in infants aged 2-4 months. A severe attack can lead to paralysis, seizures and sometimes death. Some small children sit down while playing, a position that increases the systemic vascular resistance vascular and aortic pressure, which reduces the ventricular left-right shunt and thus increases arterial O2 saturation. An auscultation detects a severe systolic murmur grade 3-5 / 6 at the left upper sternal border and central. The murmur in the tetralogy always has to do with pulmonary stenosis. The VSD has no sound because it is large and has no pressure gradient. The second heart sound (S2) is individually usually because the pulmonary component is remarkably reduced. A right pulse and a systolic thrill may be palpable. Diagnostic chest X-ray and ECG Echocardiography The diagnosis is suspected by history and clinical examination, supported by a chest x-ray absorption and an EKG and confirmed by two-dimensional Farbechokardiographie and Doppler sonography. The chest X-ray shows a shoe like heart with a concave segment of the pulmonary artery and decreased pulmonary vascular markings. A right aortic arch is present in 25% of cases. The ECG you see a right ventricular hypertrophy, sometimes a right-hypertrophy. A cardiac catheterization is rarely needed unless there is a suspicion of coronary anomaly that could affect the surgical procedure (eg. As anterior descending coronary artery from the right) can not be ascertained with echocardiography and. Treatment If symptomatic neonates: infusion of prostaglandin E1 In cyanotic attacks: Positioning, tranquilizers, O2, and sometimes medication Surgical correction newborns with severe cyanosis due to a closed ductus arteriosus need an infusion of prostaglandin E1 (0.01-0.1 g / kg / min iv), to open it again. Cyanotic spells Treatment of cyanotic attacks is to place the child in a knee-chest position (older children automatically sit down and do not develop seizures cyanotic) to create a calm atmosphere and give him O2. If the attack persists, are among the medical treatment options (in approximate order of preference) morphine 0.1-0.2 mg / kg i.v. or i.m., further i.v. Liquids for volume expansion, NaHCO3 1 mEq / kg i.v. as well as propranolol starting with 0.02-0.05 mg / kg, titrated up to 0.1-0.2 mg / kg i.v., if necessary. If these measures can not improve the attack, the systemic blood pressure with ketamine can 0.5-3 mg / kg i.v. or 2-3 mg / kg i.m. be increased (ketamine also has a positive sedative effect). Another possibility is phenylephrine starting with 5 ug / kg titrated to 20 ug / kg i.v. for an increase in effectiveness. If the preceding steps have not improved the attack or if the child’s condition rapidly deteriorated, may be necessary as a last resort intubation with muscle paralysis and anesthesia. Propranolol 0.25-1 mg / kg p.o. every 6 h can prevent relapses, but most experts believe that even a significant cyanotic attack an indication for rapid surgical intervention darstellt.Endgültige operation A complete repair consists of a closure of the VSD with a patch, an extension of the rechtsventriklären outflow tract with Muskelresektion and pulmonary valvuloplasty, as well as in a limited patch over the Pulmonalring or the main pulmonary artery if necessary. Surgery is usually done electively at the age of 3-6 months, but can always be performed when symptoms are present. Some newborns with low birth weight and a complex anatomy palliative measures the complete repair can be initially brought forward; the usual procedure is a modified Blalock-Taussig shunt, in which the subclavian artery is connected to the ipsilateral pulmonary artery by a synthetic graft. Modified Blalock-Taussig shunt var model = {thumbnailUrl: ‘/-/media/manual/professional/images/blalock_taussig_shunt_aortic_to_pulmonary_high_blausen_de.jpg?la=de&thn=0&mw=350’ imageUrl: ‘/ – / media / manual / professional / images /blalock_taussig_shunt_aortic_to_pulmonary_high_blausen_de.jpg?la=de&thn=0 ‘, title:’ Modified Blalock-Taussig shunt ‘, description:’ u003Ca id = “v37897556 ” class = “”anchor “” u003e u003c / a u003e u003cdiv class = “”para “” u003e u003cp u003eDer modified Blalock-Taussig shunt