1. Elective repair for aneurysm >5.5 cm, symptomatic aneurysms or aneurysms that grow >1cm/yr 2. Ruptured AAA
Aneurysm Detection and Management Study (ADAM) and UK Small Aneurysm Trial early open surgery vs observation in AAA 4-5.5 cm VA study with all males, UK males and females surveillance q6month with CT or US if expansion > 0.7cm at 6months or >1cm at year or symptoms got fixed no difference in survival at 4.5 yrs 60% in observation group underwent repair operative mortality low 2.7%-5%
No benefit of early surgery for aneurysms less than 5.5cm. Many patients with aneurysms 4.0-5.5 cm will ultimately require repair (~60% in 4.5yrs). Both trials fixed aneurysms if growth >1cm in one year or if they became symptomatic. Women had a higher rate of rupture in the UK trial.
Transfemoral access vs. laparotomy or retroperitoneal exposure Stent-mediated attachment vs. sutured anastomosis (eliminates need for aortic crossclamping). The dominate sources of physiologic stress, morbidity, and mortality in open repair are avoided in EVAR. EVAR requires life-long surveillance to evaluate for graft migration, endoleaks, and sac dilation.
EVAR-1 (UK, 2004) 1082 pts EVAR vs open for AAA>5.5cm DREAM (Netherlands, 2004): 351 pts for AAA>5cm OVER (US, 2009) 881 pts for AAA>5.5cm
Early mortality benefit in EVAR group: 1.7% EVAR vs 4.5% open AAA in EVAR-1 0.5% vs. 3.0% in OVER trail Less blood loss, fewer pulm complications, and shorter LOS with EVAR. Rate of secondary therapeutic interventions similar between both groups.
Early mortality benefit after EVAR lost in long-term follow-up.
EVAR shown to reduce the excessive mortality of raaa Must have availability of preop CT and 24- hour logistic capabilities Utilized for stable patients with proper anatomy (~50% of patients with raaa) 10-20% reduction in 30-day mortality
CTA with 3-D reconstruction is the best imaging for preoperative planning of EVAR repair. Without contrast important information such as presence in mural thrombus, patency of hypogastrics and occlusive disease of iliacs will be missed.
Neck anatomy is everything: Length (lowest renal artery to proximal end of aneurysm) must be > 1.5 cm. Diameter: up to 32mm; graft should be oversized 10-20% measured adventitia to adventitia.
Neck anatomy is everything Angulation: must be less than 45%-60% from longitudinal axis of aneurysm sac.
Neck anatomy is everything: Shape: cylindrical necks are ideal.
Direct leak at the proximal attachment site. Usually caused by a suboptimal neck anatomy and/or improper sizing of graft. Can also occur late as a complication of graft migration. Requires prompt intervention.
Direct leak caused by gaps in the wall of the stent-graft at sites of component separation or graft erosion. Rare, usually a late finding and specific to type of stent-graft used. Very likely to cause rupture if not addressed.
Indirect leak caused by patent lumbars or IMA causing persistence or enlargement of sac. Very common, but usually resolve spontaneously in 6 months. Indications for treatment include uncertainty of the diagnosis, aneurysm enlargement, and endoleak persistence. Treatment options: open ligation of the feeding arteries, laparoscopic ligation of feeding arteries, coil embolization of the feeding arteries, and polymer embolization of the endoleak cavity.
and Type V Type IV endoleak is related to the porosity of the graft. Seen shortly after implantation. Benign course. Endotension type V is aneurysm dilatation in the absence of a discernible endoleak.
Primary goal of follow-up is to identify impending failure; the failing stent-graft produces no physical signs or symptoms until some catastrophic event occurs (rupture) Recommendations for imaging are changing as more data is published on long-term natural history of EVAR Examples: contrast-enhanced CT at 1, 6, and 12 months and then annually Contrast-enhanced CT at 1, 6, and 12 months followed by annual US and plain radiographs if no early endoleak identified