Guidelines for the diagnosis and management of patients with thoracic aortic disease

1. Guidelines for the diagnosis and management of patients with thoracic aortic disease Circulation 2010;121

2. Introduction • Usually asymptomatic until complication-imaging required for detection and monitoring • Risk of radiation and contrast related toxicity • Results of treatment better in asymptomatic stage • Identification of genetic alterations • Potential for early detection • Targeted therapy

3. Aneurysm:permanentlocalized dilatation of an artery with at least 50% increase in diameter compared with the expected normal diameter.Covered by all 3 layers • Pseudoaneurysm:disruption of arterial wall&extravasation of blood contained by periarterial connective tissue

4. Aortic dissection:disruptionof media layer of aorta with bleeding within and along the wall of aorta • Intramural hematoma:clinical picture of dissection with hematoma in arterial wall,without an intimaldisruption.no flow in false lumen • Penetrating atherosclerotic ulcer:atheroscleroticlesion with ulceration that penetrates the internal elastic lamina.

5. Normal thoracic aortic diameter • Depends on • Age • Sex • Body size • Location of measurement • Method of measurement • Diameter increases by 0.12-o.29mm/yr at each level

7. Aortic diameter at various levels by CT

8. Aortic root dimensions by echo

9. Imaging modalities(classI) • Measurements should be taken at reproducible anatomic landmarks,perpendicular to axis of flow • CT&MRI-ext.diameter taken • Echo-internal diameter • For aortic root-the widest diameter at mid sinus level • Abnormalities of aortic morphology reported separately • Minimise cumulative radiation exposure • classIIa-aortic diameter should be related to patient's age and body size

12. Selection of most appropriate imaging study • Patient factors-hemodynamic status,renalfn,contrast allergy • Availability • IRAD-initial imaging modality was CT(61%),TEE(33%),MRI(1%)

13. CT • Advantages • Availability • Entire aorta imaged • Short time • Branch vessel invt. • Ecggating,MDCT

14. MRI • Advantage • No radiation • Identification of anatomic variants of AoD • branch vessel invt • Disadvantage • Prolonged duration • Pt.inaccessible to care providers • Gadolinium contrast not used in renal impairment

15. Echocardiography • Proximal AoD- • TEE sensitivity 88-98%,specificity 90-95% • TTE 77-80% and 93-96% • Distal AoD-TEE better • TEE blind spot-distal ascending aorta&prox.arch-interposition of trachea &lt.main bronchus

16. Acute aortic syndromes • Consists of 3 conditions-aortic dissection,IMH,PAU • 15% of AoD have an IMH without an intimal tear • Incidence 2-3.5/1,00,000 person years • Mean age of presentation 63yrs • Male predominance-65%

17. Acute dissection-within 2 weeks of onset of pain • Subacute-b/w 2-6wks • Chronic->6 wks

18. DeBakey classification: • Type I: Dissection originates in Asc.aorta and propagates to include at least the aortic arch • Type II: Dissection originates in and confined to the Asc.aorta • Type III: Dissection originates in the desc.aorta and propagates most often distally • Stanford classification system • Type A:dissections involving the asc.aorta regardless of the site of origin • Type B:dissections that do not involve the asc.aorta

20. Classes of intimal tears

21. 1.classic dissection • 2.IMH • 3.intimal tear without IMH • 4.PAU • 5.iatrogenic/traumatic

22. Evaluation • High risk conditions-(class I) • Genetic syndromes like Marfansyn.,Ehlers-Danlos • Connective tissue diseases • F/h of aortic dissection • Known aortic valve disease • Recent aortic manipulation • Known aortic aneurysm

23. High risk pain features(classI) • Chest,back or abdominal pain • Abrupt in onset • Severe intensity • Ripping,tearing,stabbing or sharp

24. High risk exam features(classI) • Pulse deficit • Syst.BP limb diff.>20mmHg • Focal neurological deficit • Murmur of AR(new) • shock

26. Recommendations for screening tests(classI) • STEMI in ECG should be treated as primary cardiac event without delay for aortic imaging unless pt. is high risk • Low and intermediate risk patients should be screened by CXR- • Findings s/o aortic d/s-definitive aortic imaging • Alternate diagnosis-manage accordingly • High risk patients should directly undergo TEE,CT or MRI • Class III- negative CXR should not delay definitive aortic imaging in high risk pt

27. Diagnostic imaging studies(classI) • Selection of imaging modality based on pt variables and institutional capabilities • If high clinical suspicion exists in spite of negative initial imaging a second study should be performed

28. Recommendations for management • BP mesured in both arms-treatment strategy based on highest reading • Patient not in shock-i.v drugs for rate and B.P control

30. Class I rec.for medical management • i.v beta blockade titrated to HR<60/min • CCB alternative if beta blocker contra. • After HR controlled,i.v vasodilators to reduce B.P to a level that maintains organ perfusion • Beta blocker used cautiously in setting of a/c AR • Vasodilator should not be given prior to rate control(classIII)

31. Recommendation for definitive management(classI) • Ascending aorta involved-emergent surgical repair • Desc. Aorta involved-managed medically unless lifethreateningcomplications • Malperfusion syndrome • Progression of dissection • Enlarging aneurysm • Inability to control BP or symptoms

32. Recommendations for surgical management(classI) • Ascending ao.dissection-aneurysmal aorta and proximal extent of dissection should be resected • Prtially dissected root-repaired with valve resuspension • Extensive dissection of aortic root-aortic root replacement with a composite graft or with a valve sparing root replacement • DeBakey type II-entire dissected aorta should be replaced

33. Class IIa • IMH-treated similar to aortic dissection in the corresponding segment

34. Endovascular interventions-not approved for dissection involving asc.aorta or arch • Intimal defect without IMH- • Asc.aorta-emergency surgery • Desc.aorta-endograft • Intimal defect with IMH • Stable pt-delay def.Rx until IMH resorbs • Desc.aorta-endovascular Rx

35. Thoracic aortic aneurysms • Rec.for medical Rx:classI • Antihypertensives to a goal<140/90(goal<130/80 for DM&CKD) • Beta blocker in Marfanssyn.&aortic aneurysm • Smoking cessation • classIIa- • Reduce B.P to the lowest point pt can tolerate with beta blocker and ACEI or ARB • ARB (losartan) for pt with Marfans syn. • Treatment with statin to target LDL-C<70mg%

36. Use of beta blockers slowed aortic root dilatation(Shores J et al;nejm 1994,Ladouceur M et al;Am J Cardiol 2007) • Beta blockers reduced aortic dilatation in c/c type B dissection(Genoni M et al;2001) • ACEI perindopril-reduced aortic root dilatation in marfans(Ahimastos AA et al;JAMA2007) • ARB-reduced aortic root dilatation in Marfanssyn(Brooks BS et al;nejm2008) • Statin use a/w decreased long term mortality in abd aortic aneurysm(Diehm N et al;2008)

37. Surgical management-asymptomatic pt.(classI) • Ascending aortic aneurysm degenerative etiology-surgical repair if diameter>5.5cm • Genetic syn.-elective surgery at diameter 4.0 to 5.0 cm • Growth rate>0.5cm/yr • Patients undergoing AVR at a diameter>4.5cm

38. Rec.for surgery-classII a • Genetic syn.-ratio of aortic root area(cm²)devided by height (m)>10-surgery indicated • Loeys Diets syn,TGFBR1&2 mutation-diameter >4.2 by TEE,or >4.4 by CT or MRI

41. Patients with symptoms s/o expansion of aneurysm-prompt surgical intervention(classI) • Endovascular stent grafts have not been approved by the US FDA for treatment of aneurysms or other conditions of asc. aorta.

42. Rec.for open surgery(asc.aortic aneurysm)-class I • Separate valve and asc.aortic replacement in patients without significant root dilatation • Patients with significant root dilatation-excision of sinuses&modified David reimplantation or root replacement with valved graft conduit

43. Rec. for arch aneurysms-classII • Partial arch replacement-asc.aortic aneurysm involves proximal arch • Replacement of entire aortic arch- • A/c or c/c dissection in an aneurysmal arch • Aneurysm of entire arch • Distal arch aneurysm that involves prox.desc.aorta • Asymptomatic pts. With diameter>5.5cm • Annual reimaging-aneurysms<4cm • Endovascular stent graft not approved

44. Recommendations for desc.thoracic aorta(classI) • Endovascular stent grafting- • Degenerative or traumatic aneurysm>5.5cm • Saccular aneurysm • Post op.pseudoaneurysm • Open repair • c/c dissection • a/w connective tissue d/s • Desc.thoracic aorta>5.5 cm

45. Thoraco abdominal aneurysm-surgery when diameter >6cm • End organ ischemia-additional revascularisation procedure recommended

46. Recommendations for genetic syn. • classI- • Marfan syn.-echo to assess aortic root and asc.aorta at diagnosis &6 months after to determine rate of growth • Annual imaging if stable and <4.5cm • More frequent imaging otherwise • Loeys-Dietz syn,other gen. mutations –complete aortic imaging at diagnosis,6months • Loeys-Dietz syn-annual MRI from cerebrovasc.circulation to pelvis • Turner syn-imaging at diagnosis for BAV,CoA,dilatationof asc.aorta. • If any abnormalities-annual imaging • Otherwise-repeat 5 to 10yr

47. Class IIa • Marfansyn planning pregnancy-replacement of aortic root and asc.aorta if >4.5cm

49. Recommendations for familial thoracic aortic aneurysms • ClassI • Aortic imaging for first degree relatives of pts with thoracic aortic aneurysm or dissection • If a mutant gene a/w aneurysm identified-first degree relatives should undergo genetic screening-those with genetic mutation undergo imaging

50. classIIa • If one or more first degree relatives of a patient affected-imaging of second degree relatives • Sequencing of ACTA2 gene in patients with f/h of thoracic aortic aneurysm or dissection