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THE CARDIAC TRANSPLANTATION

- The indications of the transplantation
- The transplantation technique

The transplantation technique

A cardiac transplantation requires two surgical teams: one takes the donor's heart and the other transplants the heart to the receiver.

A team coordinates the different operations and insures that the donor's heart is compatible with the receiver’s.

a - Removing the donor's heart

This stage is fundamental because the quality of the cardiac graft conditions the success of the graft.

The quality criteria of a cardiac graft are, for example, the following ones: donor’s age under 45, male sex, preservation period of the cardiac graft below 3 hours and compatibility of the HLA-DR system (blood compatibility) between the donor and the receiver.

The surgeon opens the thorax by cutting up the sternum (like in an aorto-coronary bypass surgery for example) then examines the heart. This one must contract normally and must not show any sign of a contusion.

The heart is then “disconnected”, since the aorta (the vessel from which blood leaves toward the organs) and the vena cava (the vessels through which blood arrives to the organs) are dissected; the heart is stopped with the help of a liquid administered through the root of the aorta (cardioplegia liquid).

The heart is then removed after having sectioned the vessels connected to the heart: the vena cava (altogether 2 veins), the pulmonary veins (altogether 4 veins), the aorta and the pulmonary artery.

The heart is immediately immersed in a cold serum solution (temperature: 4°C) and transported as quickly as possible (mainly by land and air means) toward the receiver’s hospital.

b - Implanting the donor's heart

The receiver’s sick heart is first removed: the surgeon opens the thorax by cutting the sternum (median sternotomy) and sets up an extra corporeal circulation.

The aorta and the receiver’s venae cavae are clamped and the heart can be removed. The surgeon lets a part of the right atrium in place, the part in which venae cavae are connected (veins collecting the non oxygenated blood at the level of the organs) and a part of the left atrium at the level of which the pulmonary veins are connected (veins collecting oxygenated blood coming from the lungs).

This technique allows the surgeon not to have to re-implant the veins, which avoids many complications.

The donor's heart can then be implanted. The operating technique then includes 4 bases: the left atrium, the right atrium, the aorta and the pulmonary artery.

The receiver’s left atrium (receiving the pulmonary veins) is sewn to the part complementary of the left atrium of the donor's heart, and the same is made for the right atrium.
Then, the receiver’s pulmonary artery is “plugged” in its site, at the exit of the donor's right ventricle, as well as the aorta.

The donor's heart is then purged and the air is completely evacuated. The graft then receives blood and the extra corporeal circulation is disconnected after making sure that the heart functions well.

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File last reviewed on dec 18, 2011