Transposition of the great vessels

Transposition of the great vessels

Transposition of the great vessels (TMS) – CHD: the aorta departs from the right ventricle of the heart, and the pulmonary artery from the left. Half of the babies die within the first month after birth, 2/3 do not live up to one year of age. The average life expectancy of these patients is from 3 to 19 months. Frequency. TMS is the most common congenital heart disease, accompanied by cyanosis and circulatory failure in a newborn child; frequency – 7-15% of the number of all CHD; defect takes 2nd place in the aftermath of ventricular septal defect. Boys suffer 2-3 times more often. Classification

• • Complete TMS – discordance of the ventricular-arterial junction with concordance of the connection of the remaining segments of the heart (aortic origin from the morphologically right, and the pulmonary trunk from the morphologically left ventricle)
  • A prerequisite even for a short life with complete TMS is the presence of messages between the systemic and pulmonary circulations. Therefore, complete TMS is always combined with one or another heart disease. Depending on the change in pulmonary blood flow, they are isolated
  • Complete TMS with increased or normal pulmonary blood flow (when associated with open arterial or septal defects, or aortopulmonary fistula)
  • Complete TMS with reduced pulmonary blood flow, when associated septal damage is combined with stenosis of the left ventricular outlet.
  • Corrected TMS: discordance of the ventricular-arterial junction with discordance of the junction of the atria and ventricles (transposition of the aorta and pulmonary artery is accompanied by inversion of the ventricles). Morphologically, the right ventricle receives blood from the left atrium and pumps it into the aorta. Morphologically, the left ventricle receives blood from the right atrium and sends it to the pulmonary artery. With all this, blood circulation does not suffer if there are no concomitant defects.
  • In this article only full TMS is considered. Hemodynamics Blood is shed during TMS in both directions; the larger the shunt, the less pronounced hypoxemia. The most favorable prognosis is noted in cases where a large atrial or ventricular septal defect provides the need for blood mixing, and moderate pulmonary stenosis prevents excessive blood flow to the lungs.

Clinical picture

• • Examination of the sick: immediately after birth, the sick have total cyanosis. Shortness of breath, tachycardia, an increase in the size of the heart and liver, edema, ascites are soon detected.
  • Auscultation
  • Systolic murmur of pulmonary stenosis or ventricular septal defect
  • Second tone accent on the aorta.

Research methods

• • X-ray of the heart in three projections 4 When TMS is combined with a lack of interventricular septum – hypervolemia of the lungs
  • With stenosis of the pulmonary artery – depletion of the pulmonary pattern
  • The vascular bundle is narrow in the anteroposterior projection and expanded in the lateral
  • Progressive cardiomegaly.
  • EKG
  • EOS deviation to the right
  • Overload and hypertrophy of the right heart
  • With a concomitant ventricular septal defect – left ventricular hypertrophy.
  • Echocardiography
  • Find the aorta located in front and on the right, extending from the right ventricle
  • Concomitant defects are revealed: damage to the septa of the heart or open ductus arteriosus.
  • Probing of the cavities of the heart
  • Increased blood oxygen saturation at the level of the right atrium and ventricle (compared to the vena cava)
  • The pressure in the right ventricle and aorta is the same. The same applies to the left ventricle and pulmonary artery.
  • Low levels of oxygen saturation in the blood of peripheral arteries.
  • Angiocardiography
  • With the introduction of a contrast agent into the right ventricle, the aorta extending from it, located in front, is visible.
  • With left ventriculography, the cavity of the left ventricle and the expanded pulmonary trunk extending from it are contrasted
  • Lateral angiography often reveals narrowing of the left ventricular outlet
  • Aortography is mandatory to rule out the often associated patent ductus arteriosus.

Differential Diagnosis

• • Tetralogy of Fallot
  • Tricuspid valve atresia
  • Pulmonary atresia with an intact interventricular septum.

Treatment:

indications for operations. Establishing a diagnosis or suspicion of complete TMS is an indication for emergency care for a child. In the rarest cases, when children come under the supervision of a doctor over the age of 1 year, irreversible pulmonary hypertension, as well as a severe degree of ventricular myocardial dystrophy, are excluded. Palliative surgery is aimed at increasing the size of the oval window defect (large atrial septal defect provides better mixing of the blood of the small and large circulations)

• • Closed balloon atrial septostomy: performed during probing of the heart cavities; rupture of the septum is carried out using a catheter with an inflatable balloon inserted into the left atrium. The procedure can be performed only during the first month of life. Later, the interatrial septum becomes more dense and its rupture with a balloon is impossible.
  • The Park-Rashkind operation is effective in babies aged 2-3 months and older. For a septo-stomy, a catheter with a knife blade folded at its tip is used. A balloon catheter is then inserted into the notch of the septum formed by it, with which the hole is enlarged.
  • Blalock-Hanlon operation: atrioseptectomy, used when the above operations are ineffective. Operations that correct hemodynamics include atrial inversion (Sönning and Master-da interventions). After dissection of the interatrial septum, using patches, the atrial cavities are redrawn so that blood from the pulmonary veins enters the right atrium, and blood from the vena cava enters the left atrium.

Movement of the main arteries with simultaneous transplantation of the orifices of the coronary arteries into the base of the pulmonary trunk (Jateneau operation). After the transverse intersection of the aorta and the pulmonary trunk, end-to-end anastomoses are applied between the proximal aorta with the distal pulmonary trunk and the proximal pulmonary trunk with the distal aorta. The results of operations. Mortality after the operations of Mustard and Senning does not exceed 10%. In the long term, good results are achieved in 85-90% of cases. The most severe complications: sick sinus syndrome and gradually increasing narrowing of the mouths of the hollow or pulmonary veins.

Synonyms

• • Transposition of the arterial trunk
  • Complete dextrotransposition of large vessels

See also Tricuspid Atresia, Tetralogy Famd Reduction. TMS – transposition of the main vessels of the ICD. Q20.3 Discordant ventricular-arterial junction