Replacement With Aortic Root Surgery

Introduction:

The aortic root is the main artery (aorta) connection point near the heart. Surgeons at Brigham and Women's Hospital specialize in aortic root surgery, a complex procedure to address issues like aortic aneurysms (weakened, bulging areas in the aorta) that can lead to ruptures. Experienced surgeons use advanced techniques, collaborating with a diverse team, to handle even the most challenging cases. Their expertise allows for various treatment options, including procedures that eliminate the need for long-term blood thinners and minimally invasive approaches for quicker recovery and less pain.

What Is Aortic Root Surgery?

Aortic root surgery is performed to avoid three potential issues:

• A rupture or tear in the aorta's wall is aortic dissection.

• The stretching of the aortic valve.

The likelihood of these problems occurring depends on the size of the aortic root and the reason for its enlargement. If someone is at high risk for these events, doctors may recommend aortic root surgery as a preventive measure.

What Are the Indications for Aortic Root Replacement?

Aortic root surgery might be needed:

• If a person has Marfan syndrome.

• If there are issues from high blood pressure, like an aortic aneurysm or tear.

• To lower the risk of stroke.

• Either to prevent or treat endocarditis, an infection of the heart.

• If there's a need to address an aortic aneurysm.

What Are the Types of Aortic Root Repair and Replacement Procedures?

1. Aortic Root Replacement: Removes a damaged section of the aorta and its valve. It replaces the aorta section with a synthetic tube (graft). It also replaces the aortic valve with either a mechanical or biological valve.

2. Valve-Sparing Aortic Root Replacement: Fixes aortic root issues without replacing the patient's valve; keeping the original valve avoids the need for long-term blood thinners. It lowers the risks of stroke and infection linked with valve replacement.

3. Composite Aortic Root Replacement: Surgically repairs the aortic root. It replaces the aortic valve with a prosthetic or synthetic valve made of artificial materials. The new valve is sewn into the base of a synthetic graft. It is used to address diseased aortic valves along with aneurysms in the aortic root.

4. Homograft Valve/Root Replacement: In complex cases, like endocarditis or multiple previous root surgeries. Involves using a tissue graft from a donated human heart. This approach is indicated for specific complex valve and root diseases.

How Is the Aortic Root Replacement Process Carried Out?

• The procedure is done under general anesthesia, ensuring the patient is asleep and feels no pain.

• A large incision, typically around 25cm long, is made in the chest to reach the heart. Sometimes, a more minor cut might be used.

• The heart is temporarily stopped.

• A heart-lung machine takes over the heart's function during the procedure.

• The damaged or faulty aortic valve is removed.

• A new valve, either synthetic or made from animal tissue, is put in its place.

• The heart is restarted, and the chest incision is closed.

• The entire operation typically lasts a few hours.

• Before the procedure, the patient should discuss with the doctor or surgeon to determine whether a synthetic or animal tissue replacement valve is more suitable for the case.

What Are the Different Types of Aortic Root Surgeries?

The aortic root is a crucial part of the heart, containing the aortic valve and the starting points of the left and right coronary arteries. Its unique shape ensures proper blood flow to the heart muscle. Diseases affecting this area can impact the heart's ability to pump effectively.

Types of Repair:

Mechanical Composite Root Replacement:

• For patients with aortic root aneurysms and abnormal aortic valve leaflets.

• It involves removing diseased aortic root tissue and valve leaflets.

• Replacement with a mechanical valve sewn inside a Dacron graft.

• Coronary arteries are reimplanted into the graft to complete the procedure.

Tissue Valved Conduit Root Replacement:

• For aortic root aneurysms and abnormal valve leaflets.

• Removal of diseased tissue and valve leaflets.

• Replacement with a tissue (porcine or bovine) valve inside a Dacron graft.

• Coronary arteries were reimplanted into the graft to finish the procedure.

Porcine Bioroot Replacement:

• For aortic root aneurysms and abnormal valve leaflets.

• Excision of diseased tissue and valve leaflets.

• Replacement with an entire porcine aortic root, including a porcine valve.

• Coronary arteries are reimplanted into the porcine root to complete the procedure.

Reimplantation Valve Sparing Root Replacement:

• For aortic root aneurysms with standard valve leaflets.

• It involves removing diseased aortic root tissue while preserving valve leaflets.

• Valve leaflets are reimplanted into a customized Dacron graft.

• Coronary arteries are reimplanted into the graft, and the neo-root is connected to the ascending aorta to finish the procedure.

Why Is Aortic Root Replaced?

The following reasons can worsen over time, leading to severe complications. Potential life-threatening problems, like heart failure, may arise if not treated.

• Aortic Stenosis: When the valve opening becomes smaller, it obstructs blood flow from the heart.

• Aortic Regurgitation: When the valve allows blood to flow back into the heart.

Treatment Approach: No medications effectively treat aortic valve problems. Valve replacement is recommended if severe complications are likely, provided the patient is otherwise well enough for surgery.

What Are the Risks of an Aortic Root Replacement?

• It includes infections in the wound, lungs, bladder, or heart valve.

• Possibility of blood clots forming.

• Risk of strokes during or after the procedure.

• Potential for a temporarily irregular heartbeat (arrhythmia).

• Kidney function may be temporarily reduced for a few days.

• The risk of death from the procedure is approximately 2%.

• This risk is significantly lower than those associated with untreated severe aortic valve problems.

• Most survivors can expect a life expectancy close to normal after the surgery.

What Are the Alternative Options for Aortic Root Replacements?

1. Transcatheter Aortic Valve Implantation (TAVI): The replacement valve is guided into place through blood vessels, avoiding a large chest incision. Typically considered when open heart surgery poses too many risks.

2. Aortic Valve Balloon Valvuloplasty: Involves widening the valve using a balloon. An alternative for cases where traditional surgery might be too risky.

3. Sutureless Aortic Valve Replacement: The valve is implanted without using stitches (sutures). Reduces the time spent on a heart-lung machine during surgery. Used when open heart surgery is deemed too hazardous.

Conclusion:

The aorta, the body's largest blood vessel, carries blood from the heart to the organs. Aortic aneurysms occur when the aorta weakens, leading to a bulge. Causes of this weakness include factors like cholesterol build-up, high blood pressure, and certain conditions such as Marfan's syndrome or abnormal aortic valves. When the aneurysm is in the chest, it's termed a thoracic aortic aneurysm. Treatment involves replacing the weakened ascending aorta with an artificial tube graft. In more complex cases, where replacement is needed above the aortic valve, the procedure includes both aortic and valve replacement, known as an aortic root replacement. The understanding of aortic aneurysm development is incomplete, and the course of treatment depends on factors like location and severity.