Brian PlunkettAdvanced Trainee in Cardiothoracic Surgery

Dept Cardiothoracic Surgery, RNSH

Aortic Dissection

Bedside Critical Care, Cairns, 2013

Pathogenesis

Entry tears: Asc Ao 60%, Arch 10%, Descending 30%

Intimal tear, propagates in medial layer antegrade (90%)

Pathogenesis: Risk Factors

A: age, atherosclerosis, aneurysm B: bicuspid aortic valve (fibrillin def.)

blood pressure (hypertension)

C: connective tissue disorder Marfan’s, Ehlers-Danlos, Lewy Deitz

D: degenerative cystic medial degeneration

E: trauma, iatrogenic, surgery, pregnancy

2-3 / 100,000 age 60-70 M:F >2:1

Pathogenesis

Pathogenesis

Pathogenesis

Pathogenesis: Acute Aortic Syndrome

Penetrating atherosclerotic ulcer & acute intramural haematoma

Classification

Presentation Pain – ‘ripping’, ‘tearing’

- may radiate to back Symptoms of organ malperfusion

- MI, stroke, mesenteric ischaemia Dyspnoea

-AR, tamponade, haemothorax Hypo or hypertension, BP differential AR murmur Absent distal pulses

Diagnosis

60% 95%

98%99%

Management - MedicalMedical & drug history, clinical exam: document neurology and pulses

Normalise the blood pressure (care with AR)Defer intubation until theatre if possible

Opioids, invasive monitoringPray they haven’t given aspirin, clopidogrel, clexane

Type A Essentially all patients considered (age, met’s) Resect primary tear, stabilize aortic wall End organ protection, correct malperfusion Prevent life threatening rupture, tamponade, AR,

coronary dissection

Type B Reserved for ‘complicated’ cases

Rupture or impending rupture (pain, eff.) Threatened or evident malperfusion Sometimes controversial

Surgery

Surgery

Surgery

Approaches to the Ascending Aorta

Cerebral perfusion strategies

Approaches to the Aortic Root

Bentall’s

David & Yacoub

De-branching and replacing ascending aorta

De-branching and stenting the arch

Stenting Type B dissections

10% 30 day medical mortality, 25% with surgery, paraplegia 15%+

Key points

Goals

• early diagnosis, initiate therapy before confirmation

• atypical NSTEMI – think AoD before anticoagulation

• early path to definitive therapy

• the right operation for the right patient

Pitfalls

• misdiagnosis: MI, stroke, ischaemic limb embolism

• delayed care

• failure to control, or adequately control HR & BP

- includes postoperatively!