Acute aortic syndrome: Imaging & endovascular treatment Vesna Đ urovi ć 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 – A ffects Ascending A orta 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 False lumen • Smaller • Larger (as more pressurized) • Brighter in the arterial phase • Wrapping at the level of the aortic arch • Outer wall calcification • 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 • Ascending aorta • Descending aorta • Patients with Marfan Sy. • Older patients • Compression of the true • Rupture is more frequent lumen • No compression of the • Proximal and distal lumen malperfusion sindromes • No involvement of the • Longer lesions branch arteries
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 Cons To prevent late dilatation and • Complications of the • rupture of the aorta endovascular procedure IRAD reported reduced mortality • Retrograde dissection of the aorta • in patients treated with TEVAR Stroke • (Fattori R at al, 2013) Spinal cord ischemia • ADSORB study – increased false • Paraplegia/ paraparesis • lumen thrombosis and remodeling Migration of the stent-graft • of the aorta after TEVAR (Brunkwall J at al, 2014)
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 of 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 • Complicated type B IMH and PAU should be treated and PAU should be treated medically, followed by by endovascular approach – serial imaging surveillance TEVAR (recommendation 20, ESVS CPG) (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
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