Endovascular aortic aneurysm repair (EVAR / ESVG)

Endovascular repair of an aortic aneurysm, also known as endovascular aneurysm repair (EVAR), is a minimally invasive procedure used to treat aneurysms of the aorta, typically those located in the abdominal or thoracic regions. This procedure involves placing a stent-graft within the aneurysm to reinforce the aorta and prevent rupture.

Here’s an in-depth overview of EVAR:

Procedure Overview

Pre-procedure Evaluation

1. Medical History and Physical Examination: Comprehensive review of the patient’s medical history and a thorough physical examination.
2. Imaging Studies:
   • CT Angiography (CTA): Detailed imaging to evaluate the size, shape, and location of the aneurysm and to plan the procedure.
   • MRI or Ultrasound: Additional imaging modalities may be used for further evaluation.
3. Blood Tests: Routine blood work to assess overall health and kidney function, as the use of contrast agents in imaging can affect renal function.

Procedure Preparation

1. Informed Consent: Explanation of the procedure, risks, benefits, and alternatives. The patient signs a consent form.
2. Anesthesia: The procedure can be performed under general anesthesia, regional anesthesia, or local anesthesia with sedation, depending on the patient’s health and the complexity of the aneurysm.

Endovascular Repair Procedure

1. Access Site Preparation:
   • The groin area is cleaned and prepped for the insertion of catheters.
   • Small incisions are made in the groin to access the femoral arteries.
2. Catheter Insertion:
   • Guide wires and catheters are inserted through the femoral arteries and advanced to the location of the aneurysm under fluoroscopic guidance.
3. Stent-Graft Placement:
   • A stent-graft (a tube composed of fabric supported by a metal mesh) is delivered to the aneurysm site via the catheter.
   • The stent-graft is positioned across the aneurysm and then expanded to fit snugly against the walls of the aorta, effectively excluding the aneurysm from blood flow.
4. Deployment and Confirmation:
   • The stent-graft is deployed, and its position is confirmed with imaging to ensure it is properly placed and blood flow is re-routed through the graft.
   • Any adjustments needed for optimal placement are made at this time.
5. Closure:
   • The catheters and guide wires are removed, and the access site incisions are closed.

Benefits

• Minimally Invasive: Less traumatic than open surgery, with smaller incisions and reduced recovery time.
• Reduced Recovery Time: Shorter hospital stay and faster return to normal activities.
• Lower Risk of Complications: Reduced risk of blood loss, infection, and other complications compared to open surgical repair.

Indications

• Aortic Aneurysms: Suitable for patients with abdominal aortic aneurysms (AAA) or thoracic aortic aneurysms (TAA) that meet specific size and shape criteria (Click here to read more on Aortic Aneurysm)
• High Surgical Risk: Ideal for patients who are considered high risk for open surgery due to age, comorbidities, or other factors.

Risks and Considerations

• Endoleak: Persistent blood flow outside the stent-graft but within the aneurysm sac, which may require additional interventions.
• Graft Migration: Movement of the stent-graft from its original position.
• Aneurysm Rupture: Although rare, there is a risk of rupture if the procedure is unsuccessful or complications arise.
• Infection: Risk of infection at the access site.
• Contrast-Induced Nephropathy: Potential kidney damage from the contrast agents used in imaging.

Post-Procedure Care

1. Monitoring: Patients are monitored in the hospital for a short period post-procedure for any immediate complications.
2. Imaging Follow-Up: Regular follow-up imaging (CTA or ultrasound) to ensure the stent-graft is in place and the aneurysm is excluded from blood flow.
3. Activity Restrictions: Patients are typically advised to avoid strenuous activities for a few weeks after the procedure.
4. Medication: Patients may be prescribed medications to manage pain and prevent infection.

Comparison with Open Surgical Repair

• EVAR vs. Open Surgery:
  • Invasiveness: EVAR is less invasive with smaller incisions.
  • Recovery Time: EVAR offers a faster recovery compared to open surgery.
  • Complications: Lower risk of complications such as blood loss and infection with EVAR.
  • Suitability: EVAR is preferable for high-risk patients, while open surgery may be necessary for those with complex aneurysm anatomy not amenable to EVAR.

Conclusion

Endovascular repair of an aortic aneurysm is an effective and less invasive alternative to open surgical repair for suitable patients. It provides significant benefits in terms of reduced recovery time and lower complication rates. Careful pre-procedure evaluation, precise execution of the procedure, and diligent post-procedure monitoring are essential to ensure successful outcomes and minimize risks.