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Toronto Notes 2019 Aortic Disease
■ abdominal aortic aneurysm (AAA): 90-98% are infrarenal
◆ suprarenal: starts above the renal arteries but does not involve the thoracic aorta
◆ pararenal: starts at the renal arteries but the SMA origin is not aneurysmal
◆ juxtarenal: starts immediately distal to renal arteries (there is no normal aorta immediately distal
to the origin of the renal arteries); renal artery origin is not aneurysmal
◆ infrarenal: starts distal to the renal arteries (there is some normal aorta immediately distal to the
origin of the renal arteries)
Etiology and Risk Factors
• riskfactors:smoking(currentorprior),advancedage,malesex,Caucasianrace,FMHx,presenceof other large vessel aneurysms, HTN
• degenerative
• traumatic
• mycotic(Salmonella,Staphylococcus,usuallysuprarenalaneurysms)
• connectivetissuedisorder(Marfansyndrome,Loeys-DietzSyndrome,Ehlers-DanlostypeIV
syndrome)
• vasculitis
• infectious(syphilis,fungal)
• ascendingthoracicaneurysmsareassociatedwithbicuspidaorticvalve
• aorticdissection
Clinical Features
• 75%asymptomatic
• mostcommonlyintheabdominalaorta
• commonpresentation:duetoacuteexpansionorrupture
■ syncope
■ pain (chest, abdominal, flank, back)
■ hypotension
■ palpable pulsatile mass above the umbilicus
■ airway or esophageal obstruction, hoarseness (left recurrent laryngeal nerve paralysis), hemoptysis,
or hematemesis (indicates thoracic or thoracoabdominal aortic aneurysm) ■ distal pulses may be intact
Investigations
• bloodwork:CBC,electrolytes,urea,creatinine,PTT,INR,bloodtypeandcrossmatch
• abdominalU/S(approaching100%sensitivity,upto±0.6cmaccuracyinsizedetermination)–useful
for screening and surveillance
• CTwithcontrast(accurateanatomicvisualization,sizedetermination,EVARplanning)
• peripheralarterialdoppler/duplex(ruleoutaneurysmselsewhere,e.g.popliteal)
Treatment
• conservative(forasymptomaticaneurysmsthatdonotmeetthesizethresholdforrepair)
■ cardiovascular risk factor reduction: smoking cessation; control of HTN, DM, hyperlipidemia,
regular exercise, watchful waiting, U/S surveillance with frequency depending on size and location • surgical
■ indications ◆ ruptured
◆ symptomatic (tenderness on palpation of the aneurysm)
◆ AAA: size >5.5 cm (men) or >5.0 cm (women)
■ risk of rupture depends on: size, family history of rupture, rate of enlargement (>1 cm/yr in
diameter), symptoms, and comorbidities (HTN, COPD, dissection), smoking
■ elective AAA repair mortality 2-5% for open repair (1-2% for EVAR); elective TAA repair mortality
<10% (highest with proximal aortic and thoracoabdominal repairs)
■ surgical options
◆ open surgery (laparotomy or retroperitoneal) with graft replacement – complications
• early:renalfailure,spinalcordinjury(paraparesisorparaplegia),impotence,arterial thrombosis, anastomotic rupture or bleeding, peripheral emboli
• late:graftinfection/thrombosis,aortoentericfistula,anastomotic(pseudo)aneurysm
• death
◆ endovascular aneurysm repair (EVAR)
– newer procedure
– advantages: preferred to open surgery in patients with suitable anatomy; decreased
perioperative morbidity and mortality, procedure time, need for transfusion, ICU
admissions, length of hospitalization, and recovery time
– disadvantages: endoleak rates as high as 20-30%, device failure increasing as longer follow-
up periods are achieved, re-intervention rates 10-30%, cost-effectiveness is an issue, radiation
exposure (especially in younger patients due to need for life-long follow-up)
– complications
• early:immediateconversiontoopenrepair(<1%),groinhematoma,arterialthrombosis, iliac artery rupture and thromboemboli, renal failure, impotence
• late:endoleak,graftkinkingandmigration,,thrombosis,ruptureofaneurysm, complications of radiation exposure
• death
Vascular Surgery VS7
Classic Triad of Ruptured AAA
• Hypotension/collapse
• Back/abdominal pain
• Palpable, pulsatile abdominal mass (caution
in patients with raised BMI)
Society for Vascular Surgery 2018 AAA Screening Guidelines Recommend
• One-time ultrasound screening for AAA in
men or women >65 yr with a history of
tobacco use
• Ultrasound screening for AAA in first-degree
relatives of patients who present with an AAA