Endovascular Repair of Thoracic Aortic Aneurysms - Procedure and Benefits

Introduction:

The aorta is the largest artery that carries oxygenated blood from the left ventricle to all parts of the body. An aneurysm refers to the expansion of an artery at its weakest point, usually at the site of branching. This weakens the artery, thus resulting in rupture of the artery and serious complications. An aneurysm in the aorta occurs most commonly in the region of the chest or abdomen and results in life-threatening situations due to severe bleeding after a rupture.

What Causes Aortic Aneurysms?

Aortic aneurysms are caused by various factors, like:

• Smoking and Alcohol: Habits like smoking and alcohol can increase the incidence of aortic aneurysms and weakens the artery.

• Hypertension: High blood pressure or hypercholesterolemia for a prolonged period can increase the risk of aneurysm formation.

• Atherosclerosis: Deposition of fat (plaques) in the walls of the artery can contribute to an aneurysm.

• Infection and Inflammation: Infections and Inflammatory conditions like rheumatic fever and vasculitis can cause an aneurysm as a complication.

• Aging: People above the age of 65 years are at risk of developing aortic aneurysms.

What Are the Treatment Options for Aortic Aneurysms?

The choice of treatment for aortic aneurysms depends on their size and location. Treatment options include:

• Wait and Watch: Aneurysms that are smaller in size are monitored regularly without prescribing any medications.

• Medications: Medications are prescribed to treat underlying causes like hypertension or hypercholesterolemia.

• Endovascular Repair and Open Surgical Repair: These are procedures that involve the use of grafts to treat aneurysms.

What Is Thoracic Endovascular Aortic Repair (TEVAR)?

This is a minimally invasive procedure to treat aortic aneurysms in the thoracic region. This involves the use of a stent graft to repair the aortic aneurysm and prevent rupture of the thoracic aorta.

Who Is Indicated for Endovascular Repair?

The decision to treat an aortic aneurysm through endovascular repair is made by the location, size, and growth of the aneurysm.

• Size of Aortic Aneurysm: The size threshold for repair varies depending on the patient's age, overall health, and other factors, but in general, an aneurysm greater than 5.5 cm in diameter is considered.

• Aneurysm Growth Rate: Endovascular repair may be indicated if the aneurysm is growing rapidly, which can increase the risk of rupture.

• Symptoms: The patient is experiencing symptoms related to the aneurysm, such as chest pain or shortness of breath.

• Rupture Risk: The aneurysm has a high risk of rupture, which can be determined based on factors such as aneurysm size, rate of growth, and the patient's overall health.

• Appropriate Anatomy: Endovascular repair is indicated only if the patient's anatomy is suitable. This is because the aorta is accessed through the femoral artery in the groin and there should be no major obstructions or other abnormalities that would make the procedure difficult or risky.

How Is Endovascular Repair of a Thoracic Aortic Aneurysm Done?

Before the procedure, a complete evaluation of the patient’s medical and personal history is done. Patients may be asked to cease smoking or drinking habits and stop the use of certain medications, like blood thinners. The steps involved in thoracic endovascular aortic repair include:

• Anesthesia and Incision: General anesthesia is administered. This is followed by an incision in the groin to access the femoral artery.

• Insertion of Catheter: A thin and flexible catheter is inserted into the artery and threaded up to the thoracic aorta. A dye may be injected to visualize the network of blood vessels.

• Stent Graft Placement: A stent graft (usually made of metal surrounded by polyester) is then inserted through the catheter and guided to the aneurysm in the thoracic aorta. The stent graft is designed to reinforce the weakened area of the aorta and prevent it from rupturing or expanding further.

• Stent Graft Deployment: Once the stent graft is in place, it is expanded to fit tightly against the aortic wall. The stent graft is secured in place and checked with the help of imaging.

• Completion of the Procedure: The catheter is then removed, and the incision is closed.

What Are the Postoperative Instructions to Be Followed?

After the procedure, thorough monitoring will be done to check for and minimize the risk of any complications. The patients will be asked to follow postoperative instructions like:

• Taking proper medicines as prescribed by the medical professional.

• Taking care of the incision site to prevent any infection. Change of dressings or suture removal should be followed as directed by the doctor.

• Avoiding strenuous activities like weight lifting, exercising, or swimming.

• Following a balanced and nutritious diet that is low in sodium prevents a rise in blood pressure.

It is essential to follow the post-operative instructions to prevent any risk of complications and achieve a better prognosis.

What Are the Benefits of Endovascular Repair?

Endovascular repair for thoracic aortic aneurysms offers many advantages over traditional surgery, like:

• Minimally Invasive: The procedure is minimally invasive and requires only a small incision on the groin. This results in less pain and a faster recovery period.

• Lower Risk of Complications: Complications that occur with open surgery like bleeding and infection are not associated with endovascular repair.

• Preservation of Organ Function: Endovascular repair can help preserve organ function by reducing the risk of blood loss and avoiding the need for aortic cross-clamping, which can reduce blood flow to organs.

• Less Scarring: Scarring is minimal when compared to open surgery.

• Improved Quality of Life: The overall quality of life is enhanced due to minimal scarring and a faster recovery period.

What Are the Complications of Endovascular Repair?

Endovascular repair of thoracic aortic aneurysms is generally considered a safe and effective procedure. Sometimes, it can cause complications like:

• Stent Graft Migration: The stent placed may move from its original location and cause endoleak or rupture of the vessel.

• Infection: Infection can occur at the site of the incision or surrounding the stent graft.

• Formation of Blood Clots: Blood clots may be formed, thus leading to a reduction in blood flow and life-threatening situations.

• Aortic Rupture: In rare cases, the aorta may rupture during or after the procedure.

• Nerve Damage: The nerves surrounding the aorta may be damaged during the procedure, which can cause pain, loss of sensation (numbness), or weakness.

• Kidney Damage: The contrast dye used during the procedure can cause damage to the kidneys, particularly in patients with pre-existing kidney disease.

• Others: Other potential complications include bleeding, arterial dissection, and allergic reactions to anesthesia or contrast dye.

Conclusion:

In conclusion, endovascular repair of a thoracic aortic aneurysm is a minimally invasive procedure with less pain and a faster recovery period. It is advisable to discuss the procedure, risks, and benefits with a medical professional to formulate a treatment plan after a complete evaluation to achieve the best possible outcomes.