Disease Description
Complete transposition of great arteries (tga) is the most common neonatal cyanotic congenital heart disease, the incidence rate of 0.2 ‰ -0.3 ‰. Congenital heart disease accounts for about 5% -7% of the total, ranking cyanotic congenital heart disease in the second place, male and female prevalence ratio of 2-4:1. The incidence of maternal diabetes mother up to 11.4 times higher than normal, used in early pregnancy hormones and anticonvulsants in pregnant women than the legal rate, if not treated, about 90% of patients died within 1 year of age.
Symptoms and signs
1, cyanosis
Appeared earlier, half of which exist at birth, most started within 1 month. With age and increased activity, cyanosis gradually increased. Bruising to the body of the, if concomitant patent ductus arteriosus, the difference appears purple, purple on the sticks than the lower limb weight.
2, congestive heart failure
Appear 3-4 weeks after birth, infant feeding difficulties, sweating, shortness of breath, dry wet large and small pulmonary rales, etc. congestive heart failure symptoms. Children often stunted.
3, physical examination found
Cause disease
Under normal circumstances, under the cone development of the pulmonary valve, pulmonary artery located in the left top. Subaortic cone contraction in the aorta below the right rear. Transposition of great arteries, the aortic valve developed under the cone, not absorbed, in the left anterior aorta above the pulmonary valve under the cone contraction, pulmonary artery located in the bottom for the latter. This is due to pulmonary artery connection back left ventricle, aortic forward connecting the right ventricle, subaortic cone due to the existence, and was muscular connection between the tricuspid valve, pulmonary valve exists under the non-cone structure, and mitral valve was fiber connection. Common malformations include: atrial septal defect or patent foramen ovale, ventricular septal defect, patent ductus arteriosus, pulmonary stenosis.
Pathophysiology
If complete transposition of great arteries associated with other malformations, the formation of two parallel loops. On the venous return of the inferior vena cava through the right side of aortic translocation as one shot supply of the body, and pulmonary venous return of oxygenated blood injection through the left heart to the lungs pulmonary artery translocation. Heart patients must rely on the traffic (patent foramen ovale, atrial septal defect, ventricular septal defect) or heart outside traffic (patent ductus arteriosus, collateral vessels) were mixed blood. Hemodynamics of the disease depends on whether accompanied by other abnormalities, left by the heart and pulmonary artery blood level of communication are mixed stenosis. Depending on whether ventricular septal defect and pulmonary stenosis could be complete transposition of great arteries were divided into three categories:
(1) and complete transposition of great arteries with intact ventricular septum: right ventricular hypertrophy load is added to expand, with the normal decline in pulmonary vascular resistance, left ventricular pressure decreased, left ventricular septal often biased, both eggs alone may not be a closed communication hole and the mixed arterial catheter, it is bruising, severe hypoxia.
(2) Complete transposition of great arteries with ventricular septal defect: complete transposition of great arteries with ventricular septal defect allows blood around the heart of communication are more mixed, so that to reduce bruising, but the pulmonary blood flow can lead to heart failure.
(3) complete the arterial switch with ventricular septal defect and pulmonary stenosis: hemodynamic changes similar to tetralogy of Fallot.
Diagnostic tests
1, x-ray examination
Mainly as follows: ① the Lord, pulmonary artery often has arranged around the bit, so see the main artery of the shadow of orthotopic small chip, slight depression, pulmonary, cardiac pedicle small heart shadow was "egg." ② sexual increase shadow hearts, ③ increased lung markings in most patients, if combined with pulmonary stenosis decreased lung markings.
2, ECG
Neonatal period may be no special change. Infants showed right axis deviation, right ventricular hypertrophy, right atrial hypertrophy with fashion there. Significant increase in pulmonary blood flow may occur when normal or left axis deviation, left ventricular hypertrophy. Atrioventricular canal ventricular septal defect combined left axis deviation during biventricular hypertrophy.
3, echocardiography
The diagnosis of complete transposition of great arteries of the commonly used methods. If the second ultrasound showed normal atrioventricular and ventricular arterial discordance with, you can establish the diagnosis. Often located in the right anterior aorta, from the bottom of the right ventricle, pulmonary artery located in the left, from the bottom of the left ventricle. Color and spectral Doppler ultrasound helps heart shunt, and combined malformations to determine the size of the detection.
4, cardiac catheterization
Catheter directly into the right ventricle and aorta, right ventricular pressure and aortic equal. Is also possible through the foramen ovale or atrial septal defect into the left heart chamber re-entry pulmonary artery oxygen saturation higher than the aorta.
5, angiocardiography
_Select_ive left ventricular angiography Aortic visible from the bottom of the right ventricle, the left pulmonary artery can be seen as one room from the bottom of the left ventricular angiography and _select_ive angiography can show arterial aortic position relationship, to determine whether coronary artery malformation.
Treatment
After the first correct diagnosis of hypoxemia and metabolic acidosis.
1, palliative treatment
Balloon angioplasty every room (rashkind procedure): severe hypoxia during surgery and who can not be rooted in every room made possible leakage or balloon atrial septal defect augmentation to make a lot of mixed blood in the atrium level, improve arterial oxygen saturation, so that survival to radical surgery for children.
Pulmonary artery banding surgery: complete transposition of great arteries with large ventricular septal defect can be made within 6 months of pulmonary artery banding surgery, prevention of congestive heart failure and pulmonary hypertension caused by pulmonary vascular disease.
2, radical surgery
(1) the physiological correction of surgery (senning or mustard surgery)
At 1-12 months after birth, namely heart capsule and completed within the atrial wall panels in the petition barrier, the circulation of the blood-oriented left ventricular mitral valve into the room, and the lung blood-oriented three-back tip orifice into the room right ventricle, atrioventricular discordance, and ventricular formation of large blood vessels connecting inconsistent. To achieve physiological correction of.
(2) anatomic correction surgery (swgtch surgery)
Can be carried out within 4 weeks after birth, the aorta and the pulmonary artery replantation of exchange and to achieve the correct anatomical relationship. Operation conditions are: left / right ventricular pressure ratio> 0.85, left ventricular ejection fraction> 0.45, left ventricular diastolic volume> 90% of normal, left ventricular posterior wall thickness> 4-4.5mm, wall tension of <12,000 dyne / cm. |