Transposition of the great vessels

The transposition of the great arteries usually called the dextro - transposition of the great arteries (d- TGA) and is a congenital malformation in which the aorta to the right and the pulmonary artery is connected to the left ventricle of the heart. Therefore, the pulmonary and the systemic circulation are separated and the clinical picture is, if not other malformations (eg, atrial septal defect ) and in which the ductus arteriosus is closed ( usually happens in the first few days of life ) is not compatible with life.

The TGA occurs with 10% of congenital heart disease on both as the sole abnormality or in association with a ventricular septal defect ( VSD), an additional pulmonary stenosis (narrowing of the pulmonary valve ) and other complex malformations. Since it is caused by a disturbed rotation of the outflow tract of the heart during embryonic development, it is a common symptom in the context of so-called Straight Taxien.

Disease

In the d -TGA, the main artery ( aorta) and the pulmonary artery are reversed. Do not cross over each other as in a healthy heart, but to rise in parallel on. The aorta is fed from the right ventricle, the pulmonary artery from the left. Systemic and pulmonary circulation are not connected in series, they form two separate circuits. In the fetus in the womb, this will still be compensated by natural cross-links: The ductus arteriosus connects the aorta and pulmonary artery, the foramen ovale of both atria can about these two compounds arterial ( oxygenated ) blood enter the body and the venous ( oxygen-poor ) blood to the pulmonary circulation. Closing after the birth of the fetal ( prenatal ) cross-connections, the child comes into a life-threatening condition because systemic and pulmonary circulation are now actually separated and thus the oxygen supply to the body is prevented. In more than half of the children but there is also another heart defect, such as a ventricular septal defect. This determines the degree of cyanosis.

Diagnostics

• Echocardiography almost always provides a clear diagnosis.
• A cardiac catheterization is only necessary in some cases to clarify further complications.

Therapy

Drug and Interventional Therapy

Once close PDA and PFO, one tries to keep open prostaglandin as life-saving measures the PDA with the drug. Another possibility is to extend the patent foramen ovale with the Rashkind maneuver ( tearing the atrial septum with a balloon catheter ). The result is an artificial atrial septal (ASD ).

Operations

Today's standard operation of a d -TGA is the arterial switch operation. It is performed in the first few days or weeks. Aorta and pulmonary artery are briefly separated above the heart valves and swapped reattached. The coronary arteries must also be transplanted. An existing ventricular septal defect ( VSD) is closed. The cycle now corresponds to the anatomically correct course. The children develop rather uneventful and usually normal.

Previous surgical procedures were almost identical surgical procedures after Senning or Mustard atrial switch. The atrial septum was removed and an artificial plane set on atrial diversion of venous blood, so that the oxygenated blood passes into the systemic circulation. Aorta and pulmonary artery were on the " wrong " place standing. This means that now, contrary to the natural cycle, the right heart pumps the systemic circulation and the left pulmonary circulation. Many patients operated on by these methods it is now well. However, it must be reckoned with cardiac arrhythmias in the long run perhaps the tricuspid valve may be leaking and the right Systemventrikel may be due to the high pressures, they have to give, to fail. Therefore, these operations are performed by now sufficient and positive experience with the arterial switch operation only in very rare cases.

The principle of the Rastelli operation at a d -TGA with VSD and pulmonary stenosis based on the fact that the left ventricle must exert a high pressure by a narrowing in the lower part of the pulmonary artery and therefore the light coming from the lungs of oxygen-rich blood through the VSD in the aorta can flow. The circuits are at the level of the ventricles (heart chambers ) by the insertion of a valved conduits and thus separated the functional closure of the VSD. The conduit must be replaced later depending on age and time of surgery. Because after this operation the left ventricle to the systemic circulation and the right ventricle pumps the pulmonary circulation, it is also an anatomical correction. This surgical procedure is still used today in appropriate indications.

All operations are performed by means of the heart-lung machine. Lifelong check-ups are observed and also to the endocarditis to look for.

Taussig - Bing complex

The Taussig - Bing complex is a very rare special form of TGA ( a partial TGA):

• The aorta arises from the right ventricle
• The pulmonary artery "rides " on a ventricular septal defect and takes the blood from both ventricles

Follow:

• The venous blood from the systemic circulation flows through the right atrium into the right ventricle of the heart, into the aorta, and further in the circulation.
• The oxygenated blood from the lungs flows through the left atrium into the left ventricle and then to the larger part of " riding " through the pulmonary artery ( the so connection both to the right as the left ventricle has ) back to the lungs and to a lesser extent by the ventricular septal defect in the right ventricle and then through the aorta into the systemic circulation.
• The result is an overload of both the lungs and the right heart, which can lead to failure of both organs.

Disease is by the Helen B. Taussig Erstbeschreibern ( pediatrician and cardiologist ) and Richard J. Bing ( American surgeon ) named.

Corrected transposition of the great arteries

When corrected transposition of the great arteries and levo - transposition of the great arteries ( l -TGA ) is the heart arteries, as described above, in parallel, but also the right and left ventricle are reversed. The left atrium is his blood, which he has received over the transposed pulmonary artery directly from the right ventricle. From there it flows through the aorta, and reversed the systemic circulation into the right atrium to write it into the left ventricle. Heart and pulmonary circulation are thus separated, but the left ventricle maintains the pulmonary circulation and the much weaker right ventricle the systemic circulation. The children appear after birth may initially healthy heart. Additional cardiac malformations can make this complicated disease but.

Malposition

From a malposition occurs when both great arteries arise from a ventricle according to a Double-Outlet-Right/Left-Ventrikel ( DORV / DOLV ). As this an artery and the other is wrong and fed properly, avoiding the incorrect here called " transposition ".