Abdominal Aortic Aneurysm (AAA): Endovascular Aortic Repair (EVAR)

All Steps in Detail

Step 1: Gaining access to the groin vessels

1. Scan the entire length of the common femoral arteries by ultrasound to determine the ideal puncture site. It should ideally be located at the level of the femur head while avoiding areas of ventral calcifications, intraluminal thrombus or stenoses. If these prerequisites cannot be met, an open access to the groin vessels should be considered.
2. Retrograde puncture of both femoral arteries under ultrasound guidance.This means defining the exact entry point of the needle into the artery on ultrasound and then not moving the ultrasound probe. With your other hand, guide the needle in a 45° angle until you identify the tip at your point of entry. When pulsatile flow is exiting the needle, advance the J-tipped steel wire carefully and without resistance. If in doubt, advance under fluoroscopy.
3. Oblique skin incision around the needle, ca. 1cm long. Then divide the subcutaneous tissue and the subcutaneous fascia using a mosquito clamp and predilate the vessel wall using an 8F dilator.
4. Apply a pre-close closing system if using, usually two devices per side.
5. Introduce short 8F sheaths on both sides.

Step 2: Perform your procedure

1. Bring up soft guidewire (e.g. Terumo) under fluoroscopic guidance to the proximal descending thoracic aorta on the side where you intend to introduce your bifurcated main body.
2. Exchange via any catheter to a stiff wire (e.g. Lunderquist).
3. Remove 8F sheath and exchange with large bore sheath if using. Alternatively, if using a sheathless system, bring up your main body.
4. From the other side, bring up a soft wire and then a pigtail catheter. Position the catheter slightly above the renal arteries (usually somewhere around L2)
5. Perform an angiogram of the perirenal segment including the infrarenal aorta including the bifurcation. Don’t forget the correct angles for your C-arm (usually around10-15% cranio-caudal).
6. Deploy your main body just below the lowest renal artery.
7. Cannulate contralateral limb of the main body using a soft wire and bring up a pigtail catheter.
8. Make sure your wire / catheter is indeed in the main body by (i) Rotating the pigtail catheter at the level of the proximal sealing zone OR by (ii) Angiogram via pigtail catheter inside the main body OR by (iii) Inflation of compliant balloon half in the contralateral limb and half below.
9. Use the calibrated pigtail catheter to measure the contralateral length after angiogram of the contralateral iliac bifurcation (CAVE correct angulation of C-arm).
10. Introduce stiff wire.
11. Introduce contralateral large bore sheath if using, or alternatively introduce your contralateral limb and deploy.
12. Depending on your stent graft system: Fully deploy the main body and then extend ipsilaterally if needed.
13. Balloon entire system using a compliant balloon if using.
14. Performfinal angiogram.

Step 3: Close your femoral accesses

1. Remove catheters and sheaths and close accesses using your predeployed closure devices.
2. If this does not stop bleeding adequately, consider using additional closure devices with an intravascular anchor.
3. If bleeding still persists, consider compression bandaging or, if bleeding is too strong, perform cutdown and close puncture site as appropriate.

Control of educational objects (tutors and trainees)

• Planning of the procedure including choice of appropriate stentgrafts and their sizes. (Theory and hands-on on planning & sizing workstation)
• Correct ultrasound-guided puncture technique (hands-on on puncture model)
• Correct use of different types of wires (theoretical knowledge and hands on (flow model and electronic simulators)).
• Correct use of C-arm (theory). Correct angles and centering to avoid parallax effects
• Knowledge of closure devices (theory and hands-on on puncture model)