Aneurysms & Aneurysm Screening

Mr Marcus Cleanthis Consultant Vascular Surgeon

Frimley Park Hospital

Aortic Aneurysms

• Most common in men over 65 who smoke and are hypertensive

• Are treated when above 5.5 cm• Can be treated by open surgery or stenting

Abdominal Aortic Aneurysms

Aorta larger than 1.5 times its normal diameter Oraorta

exceeds 3 cm in diameter

Clinical findings

Examination picks up only 40- 50% of AAAFalse positive diagnosis in thin individualsLow accuracy for size estimation

60% found on radiological imaging a fifth of them not palpable on examination

Clinical PresentationMost are asymptomatic, found on scanning or

examination

Back painAbdominal pain ( suspect inflammatory aneurysm)Distal embolisationAneurysm thrombosis ( rare)Primary aorto-duodenal fistula ( rare)

Mis-DiagnosisInitial Diagnosis Misdiagnosed Cases, % Average Delay, h

Renal colic 24 15

Diverticulitis 13 79

GI hemorrhage 13 17

Acute MI 8.7 13

Back pain 8.7 18

Motor vehicle accident 6.5 1.5

Sepsis 6.5 26

Other GI problem 6.5 4

Other/no diagnosis 13 18

Rupture risk<40mm <1% per yr40-55mm1% per yr55-79mm10% per yr>70mm 25% per yr

Risk factors for ruptureLarger size >55mmRapid expansion >10mm/yrHypertensionSmoking COPDFemale sex

Treatments

Open Surgical Repair

EndoVascular Aneurysm Repair (EVAR)

Open aneurysm treatment

• ENDOVASCULAR ANEURYSM REPAIR (EVAR)

Minimal invasive aortic aneurysm repair through an endoluminal approach via a remote artery.

Endovascular Aneurysm Repair•Minimally invasive

•Reduced morbidity

•Reduced mortality

•Less post-op pain

•No/minimal ITU/HDU

•Reduced hospital stay

Endovascular Aneurysm RepairTechnique

Cook Zenith Stentgraft

Aorto-uni-iliac Graft

EVAR I Trial

30-day mortality EVAR I 1.7%

TREATMENT THRESHOLDAAA diameter

• 5.0cm? 5.5cm? 6.0cm?• UK Small Aneurysm Trial

UK Small Aneurysm Trial

• 1090 patients, Aged 60-76years, Fit• Asymptomatic 4.0 – 5.5cm AAA• Randomised: Early Surgery/Surveillance• Mean FU 4.6years• Statistical analysis: Intention to Treat• Primary endpoint: death

UK Small Aneurysm Trial

UK Small Aneurysm Trial

• No difference in mortality in two groups• Cost analysis: surveillance cheaper• Conclusion: AAA <5.5cm should be managed

conservatively

Aneurysm Screening

UK AAA Screening• Men aged 65 and over are eligible for AAA screening• The NHS invites men for AAA screening during the year• they turn 65• Men over 65 who have not been screened previously

can arrange a screening appointment by contacting their local programme directly

• Screening involves an ultrasound scan that takes around 10 minutes

• The NHS AAA Screening Programme aims to reduce deaths from ruptured AAA amongst men aged 65 and over by up to 50%

Gloucestershire Aneurysm Screening

• 25,000 ultrasound invitations• 85% attendance• Costs approx. £10 per scan• 99% imaging success• 1% of aortas >4cm diameter

Gloucestershire Aneurysm Screening

• Most rupture occurred in the 15% of patients who DNA’d

• Incidence of aneurysm rupture in the screened group reduced by 85%(Scott et al Br J Surg 1995)

MASS Results

• 80% of screened group accepted invitations• 1333 aneurysms detected• 65 aneurysm-related deaths invited group• 113 aneurysm related deaths control group• 42% risk reduction in invited group• 53% risk reduction in those screened• Elective mortality 6%• Emergency surgery mortality 37%

MASS Results

Summary

• Treatment for AAA :– greater than 5.5cm– growth 1.0cm /12months– Tender AAA (inflammatory….)– Rupture AAA