Abdominal Aortic & Thoracic Aneurysms

Andris Kazmers, MD, MSPH, FACSIntegrative Cardiovascular Health and Wellness

3250 Woods Way, Suite 9Petoskey, Michigan

231-881-9700

Aneurysms & Aortic Disease

• Abnormal dilation of vessel 1.5 – 2 X native size• True vs false• Mycotic• Dissecting• Saccular vs fusiform

Additional aortic abnormalities

Journal of Vascular Surgery 2008 47, 504-512DOI: (10.1016/j.jvs.2007.10.043)

Location Male Female

Ascending 4.0 3.4

Descending 3.2 2.8

Supraceliac 3.0 2.7

Suprarenal 2.8 2.7

Infrarenal 2.4 2.2

Aortic Bifurcation

2.3 2.0

Normal Aortic Size (cm)

Normal Aortic Size

Journal of Vascular Surgery 2008 47, 504-512DOI: (10.1016/j.jvs.2007.10.043)

AAA

• Most common aortic aneurysm– AAAs 21/100,000 person-years– TAAs 6/100,000 person-years

• Increasing incidence & prevalence? 13-15th leading cause of death in US Increasing number of total & ruptured AAA True worldwide, in US recent decline Women constitute higher proportion rAAA

• Asx unless expand, rupture or embolize

AAA Diagnosis: Physical Exam

Best Case• Sensitivity 68%• Specificity 75%

Sensitivity• Girth > 100 cm 53%• Girth < 100 cm 91%

Tends to overestimate AAA size

AAA Diagnosis

• Physical exam 38%

• Incidental 62%

Abdominal Aortic Aneurysm

AAA In USA

40,000 repairs annually

> 2,000,000 with undiagnosed AAA

Estimated 9,000 deaths from rupture

Incidence AAA

• 1.5% in unselected autopsies• 3.2% in unselected ultrasound studies• 5% in CAD patients screened by USN• 10% in PVOD patients screened by USN• 12 - 20% in those with family history• > 50% with femoral or popliteal aneurysms

Screening

• One time ultrasound screening recommended in men 65 – 75 years of age who have ever smoked

• No screening recommended in women

AAA Rupture Declining Before Screening

Diagnosis AAA: Imaging

• Abdominal x-ray• Ultrasound• CT• MRI• Angiography

Diagnosis AAA: Imaging

• Abdominal x-ray• Ultrasound• CT• MRI• Angiography

Diagnosis AAA: Imaging

• Abdominal x-ray• Ultrasound• CT• MRI• Angiography

Diagnosis AAA: Imaging

• Abdominal x-ray• Ultrasound• CT• MRI• Angiography

Diagnosis AAA: Imaging

• Abdominal x-ray• Ultrasound• CT• MRI• Angiography

AAA

• Once diagnosis made, most likely cause of death defined for that individual

• Usually asymptomatic• Expand & rupture unless patient first dies from

another cause

Surveillance AAA

• USN or CT: ? every 3, 4, 6, 12 or more months

• AAA repair in men• Symptoms • Expand to 5.5 cm or more • Growth > 1 cm in one year

• Repair in women ? size

AAA: Presentation

Abdominal or back pain with AAAIf:• No syncope• Stable vital signs• Chronic vs acute pain • Stable hematocrit,then proceed with CT scan

AAA & Back Pain

CT Not Arteriography for AAA Evaluation :Angio Done During EVAR

Defined By Preop CT

• Renal or visceral artery involvement• Accessory renal artery• Renal artery stenosis• Horseshoe kidney• Peripheral aneurysms (15%)• Status of pelvic circulation• Evaluation of associated PVOD• Assess candidacy for endovascular repair

Ruptured AAA: Presentation

• Painback or abdominalmay be in unusual location

• Pulsatile abdominal mass

• Shock

Ruptured AAA: Presentation

Abdominal or back pain and syncope

Proceed to OR!( or to Endovascular Suite?)

Inflammatory AAA

• 5 - 10% AAA• Thick wall on CT, USN suggestive• Abdominal or back pain• Elevated ESR• Duodenal, ureteral adhesion• Technically challenging• Greater mortality, morbidity

AAA: Other Modes of Presentation

• Atheroembolism

• Aortocaval fistula

AAA: Infrequent Modes of Presentation

• Aortoenteric fistula

• Duodenal obstruction

AAA Rupture

Risk factors for AAA rupture

Initial AAA size Diastolic hypertensionChronic obstructive pulmonary disease

Cronenwett et. al. Surgery 98:472 1985.

AAA: Natural History

• Growth rate 0.4 - 0.5 cm per year 4.5 – 4.9 cm AAA grew 0.7cm in 1 yr* Can rupture “without growth”

• Rupture at 3 years in unrepaired AAA > 5 cm 28%*

• Rupture at 3 years in those unfit for repair 5 – 5.9 cm 28%*** > 6 cm 41%

*Brown, et. al. J Vasc Surg 23:213, 1996**Glimaker, et.al. Eur J Vasc Surg 5:125, 1991***Jones, et. al. Br J Surg 85:1382, 1998

Small AAA Rupture

• Autopsy study of those dying with rAAA*9.5% had AAA < 4 cm33% had AAA < 5 cm

• Clinical study of r AAA10% rAAA < 5cm**

*Darling, et. al. Circulation 56(Suppl 2):161, 1977**Nicholls, et. al. J Vasc Surg 28:884, 1998

Surgical Treatment AAA

• First successful direct repair: 1951, Dubost

• Surgical treatment doubled life expectancy in the 60s, despite high elective mortality rate

• Mortality elective repair decreasing 15% < 5%

Endovascular Treatment AAA

• First endovascular AAA repair (EVAR): 1991, Parodi

• EVAR operative mortality lower than open repair

Endovascular AAA Repair:Gore Excluder

• Bifurcated, modular • Nitinol with PTFE• Proximal “fishscales”• No distal hooks• 16-20 Fr ipsilateral• 12-18 Fr contralateral

Endovascular AAA Repair: Gore Excluder

EVAR Complications

• Systemic– MI, CHF, arrhythmias, respiratory or renal insufficiency

• Procedure related– Femoral arterial injury: hemorrhage or occlusion– Groin wound infection – Iliac or aortic injury– Misplacement with vessel occlusion– Thromboembolizaton– Ischemic colitis

• Device related late complications– Migration, detachment, rupture, stenosis– Endoleak

Endoleaks

More common in older grafts

• Type I leak (a: proximal, b: distal)– Persistent flow in aneurysm sac– Incomplete exclusion

• Type II– Sac filled from branches

• Type III– Component disruption

• Type IV– Endograft porosity

• Type V – Endotension: sac enlargement with

no obvious leak

Endovascular AAA Repair

Endovascular repair not possible in everyone Highly complex repairs limited to referral centers Many devices recalled, removed from market Cost >> reimbursement Need for lifelong follow-up: more late interventions Early results better after EVAR Late results, durability: comparable to open repair

AAA Repair

• OpenAnatomically unsuitable for EVARMany, not all, ruptured AAA

• EVARLower morbidity, mortality with elective or rAAAEquivalent survival up to 4 years postop Increased need for secondary procedures

Controversies

• Wait until AAA 5.5 cm in male?– Bad idea in my opinion!

• What size AAA to fix in female?: 5cm – Higher rupture rate than men at same size

• Open vs endovascular– EVAR when possible

Thoracic Aortic Aneurysms

Ascending Aorta Descending Aorta

Thoracoabdominal Aortic Aneurysms

Iliac Artery Aneurysms

• Usually associated with AAA

• Natural history poorly defined, but dangerous

• Repair those > 3 cm – Common and external: endograft– Internal: exclude, embolize– Iliac branch graft

Endovascular Management:Wallgraft for Common Iliac Artery Aneurysm

Internal Iliac Artery Aneurysm Exclusion

Endovascular Management Suprarenal Aneurysms

Snorkel

Fenestrated Grafts

Open TAA Repair

Aortic Debranching: TAA

Descending Aortic Dissection

•Type A dissections

•Type B dissections

AcuteComplicated / symptomatic

Uncomplicated /asymptomatic

Chronic

Aortic Dissection

Dissection Trials and Registry

– Best medical therapy vs BMT + endograft

– No difference in initial survival, aortic related deaths or progression of disease in early studies

– Improvement in aortic remodeling

– Improvement in late survival in those with endografting

Acute Complicated Descending Dissection

Indications for Surgical or Endovascular Treatment• Rupture

• Malperfusion

• Pain/impending rupture

•Results – low mortality, low stroke, low paraplegia rates Retrograde dissection → Type A – 2%

Reinterventions – 26%

Summary

• EVAR safer approach with expanding indications• Advances have been fast and furious• TEVAR successful for thoracic aneurysms and dissections• Fenestrated and custom grafts available