1 / 42

Abdominal Aortic Aneurysms

Abdominal Aortic Aneurysms. Elizabeth Pensler, DO Vascular Surgery Kansas City Review April 3-5 th 2014. Definition of Aneurysm. Focal and persistent dilatation of the diameter of an artery of 150% or more Transverse diameter of 3 cm or greater.

wolfe
Télécharger la présentation

Abdominal Aortic Aneurysms

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Abdominal Aortic Aneurysms Elizabeth Pensler, DO Vascular Surgery Kansas City Review April 3-5th 2014

  2. Definition of Aneurysm • Focal and persistent dilatation of the diameter of an artery of 150% or more • Transverse diameter of 3 cm or greater

  3. Normal aortic diameter gradually decreases from the thorax (28 mm in men) to the infrarenal location (20 mm in men)

  4. Types of Aneurysms • True vs. False (pseudoaneurysm) • True: involves all 3 layers of the arterial wall • False: Presence of blood flow outside of normal layers of arterial wall. Wall of false aneurysm is compose of the compressed, surrounding tissues.

  5. Types of AneurysmsEtiology • Degenerative • Incorrectly termed atherosclerotic • Not typically assoc. with occlusive disease • Complex degenerative process • Calcification and atherosclerotic pathology present

  6. Inflammatory • Triad ab or back pain, pulsatile (+/- tender) abdominal mass, elevate ESR • Dx made - periaortic inflammatory rind on CT

  7. Post-dissection- up to 20% of aneurysms are related to previous dissection. Overtime, develops into true aneurysm • Traumatic • Developmental Anomalies- persistent sciatic arteries, aberrant right subclavian artery • Infectious- Can be primary or secondary infections. • Congenital- Tuberous sclerosis, aortic coarctation, Marfan’s.

  8. Crawford Aneurysm Type

  9. Epidemiology • 15,000 Deaths per year USA • 13th leading cause of death in USA • 1.8-6.6% of patients in Autopsy series! • Strong male predominance 3:1 - 8:1 • Racial distribution Whites > Blacks

  10. Increasing Incidence of AAA • Inc. 2.6X from 2.62 deaths per 100,000 in 1981 to 6.82 per 100,000 in 2000 • Hospital admissions rose 3X • Increases in both elective admissions (from 3.05 to 7.80 per 100 000) and emergency admissions (from 7.44 to 11.23 per 100 000) • Br J Surg 2003 Dec;90(12):1510-5BestVA; Price JF; Fowkes FG

  11. Genetic predisposition • 15-20% have 1st degree relative with AAA • 11.6x more common in persons 1st degree • Duplex 25% males and 7% females have AAA if 1st degree relative has AAA • 69% risk of AAA in offspring of women with AAA! • Females rise from 14% to 35% in affected families

  12. AAA: Associated conditions • Emphysema: Strongest independent risk factor for rupture of a known AAA • Destruction elastin matrix in lung and aortic wall may have a common cause (e.g. alpha 1 antitrypsin deficiency)

  13. Range of Potential Rupture Rates for a Given Size of Abdominal Aortic Aneurysm • AAA Diameter (cm) Rupture Risk (%/yr) • <4 0 • 4-5 0.5-5 • 5-6 3-15 • 6-7 10-20 • 7-8 20-40 • >8 30-50

  14. Operative Mortality of AAA Repair • 3 – 5% for open repair • 1% for EVAR

  15. Assessing the AAA patient • Normal - aorta 1-2.4cm & iliac 0.6-1.2cm • Aneurysm - Aorta >3cm & iliac > 2cm • Average expansion rate approximately 0.33 cm per year. • Risk Factors for aneurysm • Older age, male gender, white race, positive family history, smoking, HTN, hypercholesterolemia, PVD, CAD. • Ultrasound • used to diagnose and monitor AAA until aneurysm approaches size at which repair considered. • Computed Tomography • used in preop assessment of AAA.

  16. Ruptured AAA • No significant overall change in mortality with open repair from 1991-2006 • Overall mortality for ruptured AAA = 90% • Mortality rate for patients who arrive at hosptial alive = 40-70% • High postop mortality rate due to MI, renal failure, and multi-organ failure • Ischemia-reperfusion injury, hemorrhagic shock, lower torso ischemia • rEVAR significantly reduces mortality of ruptured AAA patients (31 vs 50%)

  17. Screening for AAA • US Preventive Services Task Force • Men 65-75 yo who have ever smoked • Not for or against men 65-75yo who never smoked • Does not recommend screening for women • Society of Vascular Surgery, Medicare Screening • Men smoked at least 100 cigarettes during their life • men and women with a family history of AAA • Only screen patients candidates for repair.

  18. Choosing between Surgery & Observation • Risk for AAA rupture without surgery • Operative risk of repair • Patient’s life expectancy • Personal preferance of patient

  19. 1. Risk of Rupture • Size matters: • Aneurysm > 5cm 6-16% • > 7cm 33% annual rupture rate • Wall stress analysis • Saccular aneurysm have higher rate of rupture • HTN, COPD, active smoking independent predictors of rupture • (+) family hx tend to rupture • Expansion rate

  20. 2. Operative Risk of Repair • Mortality after: • elective open AAA ~ 5% • EVAR 1% • 6 independent RF’s for mortality Open repair • Creatinine > 1.8, CHF, EKG detected ischemia, Pulmonary dysfunction, older age, female gender. • Cardiac, pulmonary, renal, and GI risks with each proceudre.

  21. 3. Patient’s Life Expectancy • Very difficult to assess due to patient’s co-morbidities • Typical 60yo surviving AAA repair has 13year life-expectacy • 70yo has 10year life-expectancy • 80 yo has 6 year life-expectancy.

  22. 4. Personal Preference of Patient • Fear of AAA vs. Fear of surgery • Anecdotal experiences of friends and family • Procedures provided in community by interventional specialists and surgeons.

  23. Medical Management of AAA • Smoking Cessation- Single important modifiable RF • Exercise Therapy- Benefit small aneurysms • Beta Blockers- May decrease the rate of expansion? • ACE inhibitors- Evidence is mixed, however, implicated in less aneurysm rupture. • Doxycycline • Antibiotic activiety against chlamydia species • Suppresses expression of MMP • Statins - associated with reduced aneurysm expansion rates. Decreases MMP-9 in aneurysm wall.

  24. EVAR vs. OPEN • EVAR-1 and DREAM Trials • Randomized AAA > 5.5 cm to EVAR vs. open repair • Lower 30-day mortality for EVAR (1.6% EVAR vs. 4.6% open) • Peripop mortality and severe complications 4.7% EVAR & 9.8% open repair (DREAM) • Similar all-cause mortality at 2 years • Higher rate secondary interventions in EVAR • Total cost of Tx & 4 yrs of f/u inc. for EVAR.

  25. Open Repair • Transabdominal Approach • Previous retroperitoneal surgery • Ruptured AAA • Exposure of mid/distal portions of visceral vessels or R renal artery • R internal or external iliac artery • Co-existant abdominal pathology • Left-sided vena cava • Retroperitoneal Approach • Mult. Previous intraperitoneal procedures • Abd wall stoma, ectopic/ anomaly of kidney • Inflammatory aneurysm • Proximal aortic access, endarterectomy of viceral/renal arteries needed • Obese patients • Fewer GI complications

  26. Open Repair-Complications • Cardiac • Pulmonary • Renal • Lower Extremity Ischemia • Spinal Cord Ischemia • Incisional Hernia • 14.2% ventral hernia, 9.7% SBO • Graft Infection

  27. Open Repair Complications:Colon Ischemia • Collaterals from SMA, IMA, internal iliac artery, and profundafemoris supply sigmoid colon • Mortality 40-65%, full-thickness necrosis 80-100% • Occurs in 0.6-3% of elective and • 7-27% of ruptured AAA (much more common endoscopically than clinically)

  28. Colon Ischemia • Signs and Symptoms • Bloody bowel movements • Persistent acidosis & shock • Treatment • Ischemia limited to mucosa submucosa- npo, IVF, IV abx • Transmural ischemia- bowel resection, fecal diversion, creation of ostomy, washout of abdomen, IV abx.

  29. Open Repair- Concomitant Pathology • Treat most life-threatening process FIRST • Avoid simult. OR  prosthetic graft infection • If secondary procedure can be staged without increased risk - do aneurysm repair first • Clean procedures (ie:nephrectomy, oophrectomy) can be performed simultaneously • GI procedures should not occur at same time • Abort surgery if metastatic disease or abscesses which increase risk for graft infection discovered.

  30. Inflammatory AAA • Perianeurysmal fibrosis & inflammation • 5% of AAA • Treatment of AAA resolves the periaortic inflammation in 53% (open & EVAR) • Duodenum, left renal vein, and ureters often involved in inflammation. • PreOp ureteral stent placement recommended

  31. Infected AAA • 0.65% of AAA • Can be primary or secondary infection • Potential causes of infection: • Continguous spread of local infxn, septic embolization from distal site, bacteremia. • In the past syphilis and steptococcal species was common: • Now: staph and salmonella. • With HIV and wide-spread abx use- can be caused by any bacterial or fungal infection • Dx: fever, abdominal/back pain, high ESR, bacteremia.

  32. EVAR

  33. Types of Endoleak

  34. Types of Endoleak • Type I • Usually identified and treated @ time of stent graft implantation • Must be treated if found on post-op imaging • Associated with high likelihood of AAA rupture • Type II • 10-20% of post-op CT scan show Type II leak • 80% resolve spontaneously at 6 months • Indication to treat: persistent leak, aneurysm growth • Transcatheter tx (coil embolization) • Type III • 0-1.5% incidence • Strong predictor of rupture • Tx: re-establish continuity by additional component to bridge gap or cover hole. • Type IV • Majority resolve within one month of stent graft implantation

  35. EVAR complications • Stent-graft infection • Net infection rate of 0.43% • Pelvic ischemia • Internal iliac occlusion during EVAR • Si/sx: buttock claudication (most common 16-50%), buttock necrosis, colon necrosis, spinal ischemia, lumbosacral plexus ischemia, ED (15-17%). • Ischemic colitis < 2%

  36. Discussion • “No significant difference between endovascular repair and open repair in rate of overall survival at a median of 6.4 years.” • Significantly higher rate of reinterventions in EVAR group than open group • Study limited by difference in f/u between the open and endovascular group.

More Related