Acute aortic syndrome: Imaging & endovascular treatment Vesna - - PowerPoint PPT Presentation

Acute aortic syndrome: Imaging & endovascular treatment

Vesna Đurović Sarajlic Clinic of Radiology University Clinical Center Sarajevo BCR 2017, Budapest , Hungary

The term “AAS” was first introduced into the literature in 1998 to describe a variety of acute aortic pathologies:

• Aortic dissection (AD)
• Intramural hematoma (IMH)
• Penetrating ulcer (PAU)

• Clinically usually indistinguishable
• They are interrelated, and one condition may evolve into

another, or coexists with another IMH AD PAU AD

The common denominator of AAS is disruption of the media layer of the aorta

Clinical signs and symptoms

• Sudden onset of tearing and ripping chest, neck or back pain
• Pulse differences
• Acute congestive heart failure
• Neurological deficit
• Abdominal pain
• Shock

• Multi - detector CTA is the modality of choice in AAS

Sensitivity up to 100%, specificity of 98 – 99% I. Non CE phase II. CE arterial phase (with ECG gating)

• III. CE delayed phase
• TTE & TEE in unstable patients (aortic valve insufficiency,

pericardial effusion..)

• Magnetic resonance and catheter angiography are seldom

used in acute conditions

Aortic dissection

• Represents the majority of the AAS
• Prevalence 10 – 30/million/ year, twice that of AAA rupture
• Male predominance, but in women has a higher mortality rate
• Ascending aorta app. 60%, descending aorta app. 40%
• > 40 y, hypertension

Risk factors

• Congenital & hereditary

Bicuspid aortic valve, coarctation, Connective tissue disorders Marfan syndrom, Ehl. Danlos , policystic kidney disease

• Acquired

hypertension aneurysms, atherosclerosis

• Iatrogenic

cardiac surgery, wires and catheter caused

• Other conditions

smoking, dyslipidemia, cocain and amphetamine abuse

Classification systems for AD

• Stanford classification (extension of dissection):

Stanford type A – Affects Ascending Aorta Stanford type B – Distal to the left subclavian artery

• DeBakey classification (location of the entry tear):

DeBakey type I – ascending & descending aorta DeBakey type II – ascending aorta DeBakey type III – descending aorta

Stanford A Stanford B

• There is no consensus about

the classification of arch AD without involvement of the ascending aorta

ESVS Guidelines Descending Thoracic Aorta

Diagnostic features of AD:

Intimomedial flap and double lumen True lumen

• Smaller
• Brighter in the arterial phase
• Outer wall calcification

False lumen

• Larger (as more pressurized)
• Wrapping at the level of the

aortic arch

• Thrombosis

Intimomedial flap Double lumen

Coronal plane VR reconstruction

What do we report in AD?

• Primary entry tear
• Re - entry tear
• Complications:
• malperfusion of the aortic branches
• pericardial effusion & tamponade
• rupture

Stanford A Stanford B

63-year old female, hypertension, chest pain, weaknes in the left hand, confusion

Brain malperfusion – bad prognostic factor

68 year-old male, chest pain, left arm and left leg pulse deficite

Right kidny and left leg malperfusion

53 year female, hypertensive crisis, sudden onset of back pain

Intramural hematoma IMH

A hematoma within the aortic wall

• without intimomedial flap
• no visible intimal tear
• no flow in hematoma
• The classical theory of

pathogenesis of IMH is that of “rupture of the vasa vasorum”

• Incidence – app. 12% of all suspected AAD cases are IMH

(IRAD)

• A significant number of IMH will progress to plain dissection
• Up to 10% of IMH will resolve spontaneously
• The higher incidence in Asians than in Europeans and

Americans

Diagnostic feature and classification

• > 0.5mm crescentic or

circular thickening of the media, hyperdense on the non CE scans

• Stanford classification to

IMH type A and type B

IMH vs. AD

• Descending aorta
• Older patients
• Rupture is more frequent
• No compression of the

lumen

• No involvement of the

branch arteries

• Ascending aorta
• Patients with Marfan Sy.
• Compression of the true

lumen

• Proximal and distal

malperfusion sindromes

• Longer lesions

Predictors of the adverse IMH outcome

• Age of the patient > 68y
• Location of the IMH – IMH type A
• Coexistance of PAU
• Hematoma thickness

> 10 mm

• Aortic diameter

> 50 mm

Penetrating atherosclerotic ulcer (PAU)

• Progressive erosion of an

atheromatous plaque that penetrates the elastic lamina into the aortic media

• It counts for 2- 7% of all

AAS

• Usually asymptomatic

• PAUs are closely associated with

atherosclerosis of the aorta (hypertension, hyperlipidemia, AAA)

• 85% -90% are located in the

descending aorta

• PAUs in the ascending aorta and the

arch are more prone to rupture

PAU type A PAU type B

Complications of PAU

PAU > 20 mm x 10 mm increases the risk of :

• Hematoma formation
• Pseudoaneurysm
• Rupture

Treatment concepts in the ASCENDING thoracic aorta

• Surgical repair - AAS

involving ascending aorta

• Endovascular repair - in the

early phase of application

Treatment concepts in the DESCENDING thoracic aorta

• Level A evidence does not exist in the management of DTA
• “Management of Descending Thoracic Aorta Diseases”

(Clinical Practice Guidelines of the ESVS 2017)

• offer the best medical evidence available and the best

consensus amongst key experts in the field

Uncomplicated acute type B dissection

• Acute dissection- within the first 14 days after the onset of

symptoms

• Medical therapy with antihypertensive drugs is widely

accepted to be the first line treatment ( SBP 100-120; HR <60 beats/min)

• Adequate clinical and imaging surveillance (MR or CTA 3m,

6m, yearly)

TEVAR in Uncomplicated acute type B AD “To treat or not to treat”

Pros

• To prevent late dilatation and

rupture of the aorta

• IRAD reported reduced mortality

in patients treated with TEVAR

(Fattori R at al, 2013)

• ADSORB study – increased false

lumen thrombosis and remodeling

• f the aorta after TEVAR

(Brunkwall J at al, 2014)

Cons

• Complications of the

endovascular procedure

• Retrograde dissection of the aorta
• Stroke
• Spinal cord ischemia
• Paraplegia/ paraparesis
• Migration of the stent-graft

Selection of the patients

Radiologic pred. of growth

• One entry tear (ET) , the size

>10mm

• Entry tear at the concavity
• False lumen > 22 mm
• Eliptic true lumen and round false

lumen

• Early thoracic endografting may be considered selectively to

prevent aortic complications in uncomplicated acute type B dissection, (recommendation 18, ESVS’ CPG)

• To facilitate the patient selection process, important clinical

and anatomical features were summarized in a new categorization scheme DISSECT (M.Dake at al, 2013)

Complicated acute type B dissection

• Endovascular repair with thoracic endografting should be the first

line therapy (recommendation 16, ESVS CPG)

• Endovascular repair is associated with lower peri-operative

morbidity and mortality rate than OR (2,5 9,8% : 25-50% mortality rate)

• Technical success of TEVAR ranges from 95 to 99%, hospital

mortality from 2,6 to 9,8%, neurological complications from 0,6 to 3,1 % (6,96,97)

The goals of TEVAR are:

• Coverage of the primary

entry tear

• Decreased pressure in the

false lumen/ repressurisation

• f the true lumen
• Reperfusion of branch

vessels

• Thrombosis of the false

lumen

• In complicated type B AD,

patients presenting with malperfusion, experience the poorest outcome

• Endovascular fenestration should

be considered in these patients to treat malperfusion

(recommendation 17, ESVS CPG)

Acute type B IMH and PAU

• Uncomplicated type B IMH

and PAU should be treated medically, followed by serial imaging surveillance (recommendation 20, ESVS CPG)

• Complicated type B IMH

and PAU should be treated by endovascular approach – TEVAR

(recommendation 21&22, ESVS CPG)

Future prospectives

• To assess the management controversies of uncomplicated acute

type B dissections, larger randomized controlled trias should be conducted

• The timing of the procedure is of special interest in

uncomplicated type B aortic dissections

• Definition of early unfavourable clinical and imaging signs to

select the patients who would benefit the most from an early TEVAR procedure