Two types of aortic root surgery are performed at Mayo Clinic: aortic root replacement and valve-sparing aortic root repair.
In aortic root replacement surgery, the aortic valve and the affected segment of the aorta are replaced with either a mechanical valve or biological components.
Mechanical valve
If the valve is mechanical, the surgery is sometimes referred to as a composite valve-and-graft procedure because the valve and graft are combined into one piece. After the graft is sewn in, the patient's coronary arteries (which attach to the aorta just above the valve leaflets) are reimplanted into it.
After the graft is sewn in, the patient's coronary arteries (which attach to the aorta just above the valve leaflets) are reimplanted into it.
The advantage of a mechanical valve is its long-lasting durability. The disadvantage is that it carries a higher risk for a blood clot, which can cause a stroke. Therefore, the patient will need to take long-term anticoagulation (blood-thinning) medication, which carries a small risk of serious bleeding and requires monitoring.
Biological (tissue) valve
Xenograft (from pig or cow)
This procedure may be performed using either a stented or stentless valve. A stent is a flexible plastic frame on which the valve leaflets are mounted. The frame is covered with a fabric ring used by the surgeon to sew the valve into a Dacron graft. The procedure then closely resembles mechanical valve replacement. A stentless xenograft omits the frame and instead retains a portion of the animal's aorta. Mayo Clinic surgeons have extensive experience with both types.
Homograft
In a homograft procedure, a preserved valve and aorta segment from a human cadaver are used as a replacement.
Autograft (Ross procedure)
In a few circumstances, the patient's own pulmonary valve may be used to replace the aortic valve. The pulmonary valve is then replaced with a homograft. Mayo Clinic surgeons usually perform this procedure only in children, where the continued growth of the child and the autograft reduce the risk of later complications associated with the procedure.
The advantage of a biological valve is that patients do not need to take long-term anticoagulation medication. The disadvantage is that it is less durable than a mechanical valve and the patient may need surgery again after 10 to 15 years.
A re-implantation procedure is the primary surgery used by Mayo Clinic surgeons to preserve the patient's natural valve while replacing an enlarged aorta. It is referred to as a David procedure — after the surgeon who first performed it.
In this procedure, the damaged portion of the aorta is removed, but the segment containing the valve remains attached to the heart.
After detaching the coronary arteries and removing surrounding soft tissue, including the sinuses of Valsalva (pouches behind the valve leaflets that allow them to gently open and close), a tubular Dacron graft is sewn to the base of the heart around the outside of the valve leaflets.
The valve is then re-implanted inside the graft by stitching the leaflets to it, following their semi-lunar shape to create new sinuses into which the coronary arteries are then re-implanted.
As in biological valve replacement, valve-sparing aortic root repair does not require long-term anticoagulation medication. Only patients with a sufficiently functional aortic valve, however, are good candidates for valve-sparing surgery.
Aortic root surgery is open-heart surgery and involves placing the patient on cardiopulmonary bypass. In rare cases when the aortic arch must be replaced as well, treatment may involve cooling the body temperature such that blood flow can be stopped for a few minutes while the repair is carried out. After the repair, blood flow is restored and the patient is re-warmed.
How long an operation takes depends on the procedure and the individual. The typical postsurgery hospital stay is about a week and overall recovery takes about four to six weeks.