TEVAR/EVAR — Learn IR

Descending thoracic or abdominal aortic aneurysms >5.5 cm (5.0-5.4 cm for women or connective tissue dx), >2xs native aorta, or >0.5 cm increased in 6 mo or 1 cm per year
AAA/ectasia associated with a common iliac aneurysm
Contained ruptured AAA
Complicated type B dissection - debated

Complicated = aneurysmal dilation, visceral malperfusion (e.g. L>R kidney), intractable pain, rapid expansion, uncontrollable HTN
Some data that TEVAR/EVAR improves 5 yr mortality and prevents aneurysmal deterioration

Allergies to graft material
Inadequate anatomy for available device (historic cut offs below but newer devices can accommodate)

Proximal landing zone needs to be at least 10-15 mm, <3.2 cm in diameter, and angulation <60*
Iliac diameter >7 mm for device and angulation <90*

Severe contrast reactions
Marfan and Vascular Ehlers-Danlos syndrome
Indispensable IMA
Mycotic aneurysm (relative, some may consider if poor surgical candidate with lifelong antibiotics)

CTA > MRA to characterize anatomy and plan procedure (sizing specific to specific device)

Generally: oversize 10-20%, 20-36 mm devices for necks 19-32 mm in diameter
Proximal neck diameter measured at level of lowest renal and 10-15 mm below, generally oversize 10-20%, 20-36 mm devices for necks 19-32 mm in diameter
Proximal neck angulation: <40* (mild), 40-60* (moderate), >60* (severe)
Distal seal: 10-15 mm oversized 10-20%, may need to extend to EIA and coil IIA if CIA is aneurysmal
If covering left subclavian, need to confirm bilateral patent vertebral arteries or perform carotid to subclavian bypass

(Optional) Prophylactic spinal catheter placement/CSF drainage to prevent spinal ischemia. if
- Higher risk of spinal ischemia if MAP <70, stent graft length >20 cm, coverage between T8-L2, or history of prior AAA repair

Goal spinal perfusion pressure of 70 mmHg, intermittent CSF drainage to maintain pressure of 10 mmHg and permissive HTN to maintain MAP of 80 mmHg

Large Fr CFA access (device specific). Need bilateral for EVAR. Consider placing PreClose around sheaths at the beginning.
Advance working wire into the aorta followed by a flush catheter, e.g., 5 Fr pigtail.
Aortogram to confirm anatomy (e.g. 12 mL/s for 24 mL).
Advance stiff working wire(s) for device deployment.
Advance and deploy device (oversized 10-20%, overlap ≥5 mm if multiple)

Approved devices for TEVAR: TAG (Gore), Talent (Medtronic), Zenith TX2 (Cook)
Approved devices for EVAR: AneuRx (Medtronic), Excluder (Gore), Zenith Flex (Cook), Powerlink (Endologix), Talent (Medtronic)
Consider using softer wire for iliac limb deployment to avoid kinks or identify them early

Molding angioplasty as needed (oversize 5-10% for dissection, 10-20% for aneurysm).
(Optional) Chimney or stents for juxtarenal aortic aneurysms. Often Viabahn stent grafts oversized ~30%.
- Fenetrated graft (FEVAR):
  - Can preorder with up to 2 fenestration and a scallop or large fenetration for SMA (mainly by Cook) or custom made (can’t do with Gore device)
  - Higher rate of renal injury/dysfunction. Orient outside patient, 7 Fr Ansel sheaths into each renal with VBXs ready to go.
- Chimney (CHEVAR)/Parallel grafts (PEVAR):
  - Tend to go faster than fenestrated endograft, but downside is gutter leak. Avoid in shaggy aorta, neck <20 mm or >30 mm in diameter.
  - Type 1a endoleak 8%. Oversizing 30% (20-40%) is ideal. Self expanding stents have higher compression compared to balloon expandable.
Remove sheaths/wires and achieve hemostasis.

Type II Endoleak Embolization

Often initially monitored as many (~⅓) will thrombose spontaneously or remain stable.

Followed at 30d -(stable)> 6 mo -(stable)> one year. Often people intervene if stable or growing at 6 mo.

If IMA is patent, SMA -> IMA transarterial access is a good place to start.
If IMA is occluded, think about iliolumbar or lumbar arteries, otherwise, direct translumbar puncture of the sac with a 22G chiba using fluoroscopic landmarks.
Translumbar vs transarterial has mixed data re safety and efficacy, main risk is non-target embolization and recurrence.
Additional option is transcaval access with amplatzer, septal occluder, or no closure. Repeated 80-90+% technical success.
Another option is peri-graft catheterization by wedging a 5 Fr catheter between iliac wall and graft.

Embolization of inflow and nidus, often with coils and/or onyx or glue (e.g. lipiodol : histocryl, 3 : 1)

Endoleaks (25-35%, old data), postimplantation syndrome (low-grade fever, back pain, mild leukocytosis, elevated CRP, resolves in 1 wk), spinal cord ischemia (3.2% vs. 8.2% w/ surgery), stroke (3-7%), aortic perforation, device malposition

Primary (<30d) vs secondary (>30d) and Simple (single ingress/egress vessel) vs Complex (>=2)
Endoleak type I (3-4%): attachment site is inadequate superiorly (IA) or inferiorly (IB) -> endoanchors, Palmaz stent, extension cuff -> embolize (e.g. Onyx), risk of rupture ~0.5%
Endoleak type II (11%): patent brack vessel (IIA) or vessels (IIB) supplying retrograde flow; no a/w increased aneurysm related mortality
Endoleak type III (1%): structural defect in endograft, higher risk of rupture (3.4%)
Endoleak type IV (<1%): diagnosis of exclusion due to porosity of endograft
Endoleak type V (2%): continued aneurysm expansion in absence of confirmed endoleak

Iliac limb occlusion (0.7-6.4%) - more common when extending to EIA, tortuosity, EIA <10 mm

Some monitor in ICU for minimum of 12-24 hrs other do it on the floor, maintaining MAP >90-100 and SBP >140 (hold antiHTN meds, may need Levophed)
Lumbar drain if high risk of ischemia - <20 mL/hr, <10 mmHg for 24 hrs then 20 mmHg for 24 hrs then clamp
Follow up CTA at 1, 3, 6, and/or 12 months followed by duplex US monitoring after