AAA Before the Bubble Bursts

AAABefore the Bubble Bursts

June ‘XXPresents to Beaumont A&E c/o Abdominal Pain B/G: Known AAA

Radiating through to the backConstant for 24 hrsVomit x 6Fever, MalaiseNo Hx of

Haemoptysis PR Bleed G.I Symptoms

O/E:Abd SNTTender, Expansile , Pulsatile MassNo Signs of Rigidity or Guarding Peripheral Pulses: Present Bilaterally No Other Abnormal Findings

Ix:FAST Scan Performed:

No Increased Size of AAA Last AAA Scan Oct ’12 - 4.5 cm

Work up for Differential Dx

General Surgical ConsultOGD: NormalPFA: Normal Glasgow EMRIE Score: 0Ultrasound Abd: Normal

SummaryB/G Hx: Known AAATender Central MassHaemodynamically StableAll other differentials have been out ruled

Impression: Symptomatic AAA

What would you do next?

CT Aortic Angiogram

Plan1. Admit Patient2. Analgesia3. DVT Prophylaxis4. CT Aortic Angiogram:

AAA- 4.5cm No Evidence of Leakage or Rupture No Evidence of Retroperitoneal Bleed

5. EVARPatient Discharged 3/7 Post-Op

EVAR Completion Angiogram

Indications for AAA Repair

Standard Practise AAA Repair is performed when:

Diameter >5.5cmSymptomatic Ruptured AAAThe presence of other Large Vessel AneurysmsRapid Rate of Expansion

Treatment Options: EVAROpen Repair

Annual Risk of Rupture

<4.0 cm = <0.5%4.0 to 4.9 cm = 0.5 to 5%5.0 to 5.9 cm = 3 to 15%6.0 to 6.9 cm = 10 to 20%7.0 to 7.9 cm = 20 to 40%>/=8.0 cm = 30 to 50%

UKSAT TrialFirst trial of its kind to compare Surveillance vs

Open repair for small asymptomatic AAA 4.1-5.5 cm

Large study done in the UK between 1994 and 1998

1090 participants 83% male

Infra-renal Asymptomatic AAA

Results Non-Significant Survival Benefit for

Intervention Group.

6 years Survival was 64% in Both Groups

30-day Post-Operative Mortality 5.6%

Cost £1,064 more overall for EVAR group

Overall Survival

Recommendations

Surveillance strategy based on minimized likelihood of growth >5.5cm to <1% probability:

3.5 - 3.8cm = 36 months 4.0 - 4.4cm = 24 months 4.5 – 4.9cm = 12 months 5.0-5.4cm = 3 months

Current UK/NI guidelines

3.0-4.4cm 12

months 4.4-5.4cm 3

months

Render unto C.A.E.S.A.R…Comparison of Surveillance Versus Aortic Endografting For Small Aneurysm Repair

First large trial to compare Surveillance Vs Immediate EVAR

Randomised Control Trial

Trial involving 20 approved European/Western Asian hospitals

4.1-5.4cm Asymptomatic AAA

Patients Enrolled between 2004- 2008

378 participants

CAESAR trialInclusion criteria: Exclusion criteria:

AAA 4.1-5.4cm diameter

50-79 years of age

Suitable for EVAR by CT scan

Minimum 5 year Life Expectancy

Severe comorbidities

Suprarenal/Thoracic aorta ≥4.0cm

Needed Urgent Repair

Unable or unwilling to give informed consent or follow the protocol

Method

Surveillance Group: 6/12 U/S Scan 1 yr CT Indications for progression

to Repair: Aneurysm grew to 5.5cm Rapid increase in

Diameter Became Symptomatic

• EVAR Group: Graft Standardised: Zenith

AAA Endovascular Graft Follow up:

6/12 U/S + Clinical Exam 1 yr Abdo X Ray + CT scan

CT mandatory for Aneurysmal Diameter and suitability for EVAR before Randomisation as well as follow up

Estimates of All Cause Mortality in EVAR vs Surveillance Groups

Estimated Probability of Delayed Repair in Surveillance Group

months 36 52

41-44mm

23.3% -

45-49mm

57.6% 76.1%

50-54mm

90% 95%

Cumulative probability for Aneurysmal Repair in 3 Groups based on Size at Presentation

Results

Rupture rate below Annual Rate of 1%: Surveillance: 2 Ruptures

5.6cm & 5.5cm Had been Scheduled for

EVAR

Aneurysm Related Mortality: EVAR: 1 Surveillance: 1

16.4% Surveillance Group Lose Eligibility for EVAR

Positive Association with Delayed Repair:

Absence of Diabetes Absence of Peripheral Vascular

Disease

Predictor for Delayed Repair: Large Aneurysm Diameter Absence of Hypertension under

Medical Management

•All Cause Mortality • Determined to be Insignificant• EVAR 14.5% Vs Surveillance 10.1%

DiscussionSurveillance provides a Safe Alternative

Management for AAA 4.1-5.4cmRequires Accurate Imaging and Close Monitoring

EVAR suitability before and after Randomisation left at Discretion of Participating Centres

Need to Optimise Best Medical Management:Only 47% on statin

Peri-Operative risk: 0.55% EVAR Vs 5.8% Open repair (UKSAT)

Cochrane Review for Surgery for Small Asymptomatic AAAs:

Metanalysis of Long Survival for Asymptomatic AAA 4-5.5cm

3,314 Patients

Randomised Controlled Trials:Open: UKSAT, ADAMEVAR: CAESAR, PIVOTAL

Comparing Immediate AAA Repair Vs. Surveillance

ConclusionThe studies Indicate no Long Term Benefit between the

Control Groups and does not favour Immediate EVAR

The Surveillance control group showed better Survival Rates in the Early Stages due to the 30 day Post-Operative Period.

31-75% Surveillance Group eventually require Repairs

~60% Require Repair within 1 year

Review Illustrates need for more Information on Patient Demographics so Surveillance can be performed appropriately for Sub Groups based on Age, Gender, Aneurysm Morphology