Ταξινόµηση οξέων αορτικών συνδρόµων

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1 !!!!!!!!!! ΕΑΑΑ

2 Ταξινόµηση οξέων αορτικών συνδρόµων

3 Acute aortic syndromes The common denominator of AAS is disruption of the media layer of the aorta with Bleeding within IMH, Bleeding along the aortic media resulting in separation of the layers of the aorta (dissection), or Bleeding transmurally through the wall in the case of ruptured PAU or trauma European!Heart!Journal!(2012)!33,!2635!

4 Age Classic dissection or its preceding stage of IMH with no evidence of PAU are considered more prevalent in a middleaged population. Clinical instability of PAU: focal precipitation of a longstanding atherosclerotic process primarily in the descending aorta of elderly patients Circulation. 2002;106:

5 Life-threatening effects of acute aortic syndrome Mortality from acute ascending aortic (type A) dissection increases rapidly immediately after presentation, reaching 1 2% per hour for the first 48 h. Ascending aorta IMH and PAU are likewise at increased risk of lethal complications. The mortality from IMH is 21%; 16% of patients with IMH will evolve to classic aortic dissection over time

6 risk factors

7 Clinical symptoms associated with acute aortic syndromes K.!Subramaniam!et!al.!(eds.),!Anesthesia)and)Periopera/ve)Care)for)Aor/c)Surgery,2011!

8 AAS Differential Diagnosis Considerations in the emergency setting The chest X-ray may or may not reveal a widened mediastinal contour. ECG changes (non-specific, pericarditic, ischaemic, or infarction) are common. Differential diagnosis: acute coronary syndrome, pericarditis, and pulmonary embolism acute aortic regurgitation without dissection, mediastinal tumors, perforating peptic ulcer, acute pancreatitis cholecystitis, and musculoskeletal pain Not only may consideration of these conditions result in crucial delay in the diagnosis of type A AAS, but also their initial management (in ACS and PE) includes anti-platelet, anticoagulant, and thrombolytic therapies, with potential disastrous results.

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11 Echocardiographic views of the aorta

12 Transthoracic echo in suspected AAS Pericardial or pleural effusions Bicuspid aortic valve Aortic root dilatation Dissection flap AR :severity and mechanism LV and RV function assessment. Regional wall abnormalities : coronary involvement in the dissection flap or pre-existing CAD.

13 TTE: long axis parasternal/right parasternal (A) Parasternal!long!axis!view:! ascending!and!descending!aorta! (B)!Right!parasternal!longCaxis!view:! mid!and!distal!parts!of!ascending!aorta!!! European!Journal!of!Echocardiography!(2010)!11,!645658!

14 TTE: suprasternal/2c/subcostal view (A) (B) (C) Suprasternal!view!of!aorOc!arch!and!supraCaorOc!great!arteries.!! Mid!part!of!the!descending!thoracic!aorta!visualized!by!long!axis!view!from!apical!window.!!!!Abdominal!aorta!visualized!by!subcostal!view.! European!Journal!of!Echocardiography!(2010)!11,!645658!

15 Diagnostic field of echocardiography in pts with circulatory failure associated with acute aortic syndrome Echo!can!depict!blood!extravasaOon!in!pericardial,!pleural!or!abdominal! space!secondary!to!complicated!acute!aoroc!disease!

16 TTE with harmonic imaging

17 Contrast(TTE:,similar,accuracy,to,TOE,in,the,diagnosis,of,type,A,aor;c,dissec;on! (sensiovity!93%!and!specificity!97%)! European!Journal!of!Echocardiography!(2010)!11,!645658!

18 TEE in AAS TEE is reported to have a sensitivity of % and specificity of % for identifying an intimal flap. The reduced specificity in early studies relates to the false-positive interpretation of reverberation artefacts in the aortic root particularly with the use of mono- or bi-plane TEE. The most recent studies reported 100% sensitivity and 100% specificity for TEE, helical CT, and MRI, whereas conventional CT is less accurate (sensitivity 83 94%, specificity %). The TEE blindspot caused by the interposition of the trachea between oesophagus and upper ascending aorta may not be a problem, given the extremely low probability of dissection of IMH confined to this precise location only. TEE is rapid and safe. It may be performed at the bedside, or in the operating room when there is a high degree of suspicion for type A dissection or IMH.

19 TEE The primary aim of TEE is to identify the intimal flap, false lumen, and entry tear, delineate the extent of aortic dissection, and identify IMH or PAU. Secondary objectives are to provide important information to cardiac surgeons, such as the AR severity and its mechanism, branch involvement of coronary/head and neck, extravasation of blood

20 TEE execution Large studies never reported fatal cases during TEE. Given a mortality rate of 1 2% per hour, a high risk of fatal deterioration exists when performing an overlong examination. TEE execution by well trained and experienced operators in this setting is vital careful and continuous monitoring of heart rate, blood pressure, and oxygen saturation. opioid analgesia iv nitroprusside and beta-blockers for maintaining an optimal low blood pressure (e.g., systolic blood pressure < 120 mmhg). sedation: iv midazolam.

21 Transoesophageal echo

22 Intraoperative TEE Peri- post procedural TEE Pre post procedure Aortic diameter estimation (decision for AV replace or repair) Preexisting valvular disease Bicuspid valve Degenerative valve disease AR quantification / aetiology : Severe AR in up to 45% of ascending aorta dissections Entry tear location Coronary ostia Facilitates guidewire positioning into true lumen Correct selection of stent graft diameter Detection of peri-stent leaks Minerva!Cardioangiol!2010;58:409C420!

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24 IVUS Intravascular ultrasound is advocated to complement angiographic information in aortic dissection IVUS enables visualization of the vessel wall from inside the aortic wall. Its particular advantages are dynamic visualization of the true and false lumen, detection of false lumen thrombosis with higher sensitivity and specificity than those of TEE, and a better definition of branch vessel involvement than that provided by TEE or CT. IVUS may clarify the precise mechanism of vessel compromise (e.g., to determine whether the dissection membrane is intersecting and narrowing the ostium or it is covered by a prolapsing flap). Accurate visualization of aortic hematomas as crescent-shaped or circumferential thickening of the aortic wall is easy. Expert!Opin.!Med.!Diagn.!(2012)!6(6):529C540!

25 TEE IVUS descending aorta dissection Expert!Opin.!Med.!Diagn.!(2012)!6(6):529C540!

26 Aortic dissection

27 acute dissection the incidence of acute dissection ranges from 2 to 3.5 cases per person-years; hypertension and a variety of genetic disorders with altered connective tissues are the most prevalent risk conditions. Regarding time from the onset of initial symptoms to the time of presentation, acute dissection is defined as occurring within 2 weeks of onset of pain; subacute, between 2 and 6 weeks from the onset of pain; and chronic, more than 6 weeks from the onset of pain. European!Heart!Journal!(2012)!33,!2635!

28 Aortic dissection The vast majority of dissections originate from intimal tears in the ascending aorta within several centimeters of the sinuses of Valsalva where torsional movement of the aortic annulus provokes additional downward traction in the aortic root and increases longitudinal stress in that segment of aorta. The other common site for an intimal tear to originate is in the descending aorta just distal to the origin of the subclavian artery at the site of the ligamentum arteriosum. Tears occur in the isthmus area because of increased tension at the union of the relatively mobile aortic arch with the fixed descending thoracic aorta. K.!Subramaniam!et!al.!(eds.),!Anesthesia)and)Periopera/ve)Care)for)Aor/c)Surgery,2011!

29 Aortic dissection classification Type,A, Type,B,

30 Aortic dissection: ESC classification dissec;on, IMH, In;mal,tear, PUA, Iatrogenic, injury,

31 Aortic dissection prognosis surgical vs medical management Type A aortic dissections are highly lethal. Overall, mortality at 1 month is 20% with and 50% without surgical treatment for type A dissections. For type B dissections, the overall mortality rate at 1 month is 10% with medical treatment. Type B dissections with ischaemic complications (renal failure, visceral ischaemia, or contained rupture) often require urgent aortic repair which carries a mortality of 25% at 1 month. European!Heart!Journal!(2012)!33,!2635! K.!Subramaniam!et!al.!(eds.),!Anesthesia)and)Periopera/ve)Care)for)Aor/c)Surgery,2011!

32 Intimal flap:the classic sign of aortic dissection Entry tear Intimal flap: mobile linear echo separating the true from the false lumen with flow on either side. false lumen >> true lumen. Dissection flap Entry tear moves throughout the cardiac cycle (antegrade flow during systole) chronic dissections: mobility of intimal flap aortic wall thickness > 15 mm suggests dissection with thrombosis in the false lumen. entry tears are found at site of greatest wall stress> 5 mm and located in the proximal part of the ascending aorta in type A dissections and immediately after the origin of the left subclavian artery in type B dissections Pulsed Doppler: the flow velocity at the tear is usually > 1.5 m/s and the flow goes from the true to the false lumen in systole

33 TTE in aortic dissection Transthoracic echocardiography has 78% -100% sensitivity in ascending aorta dissection, but only 31-55% in descending aorta. Thus, it constitutes an acceptable technique for type A dissection, but not for type B. The low negative predictive value of transthoracic echocardiography does not permit the diagnosis of dissection to be ruled out, and further tests will be required Parasternal view: it is possible to see the aortic root, the lower third of the ascending aorta and also part of the descending thoracic aorta behind the left atrium Right parasternal view : visualization of the major part of the ascending aorta when the study is of good quality Suprasternal view: The aortic arch, the origin of supra-aortic trunks and the proximal third of the descending aorta, can be assessed Modified apical view and the subcostal approach: distal portion of the thoracic aorta and the start of the abdominal aorta can be viewed. The use of colour Doppler: may aid diagnosis of the dissection when two different flow patterns, separated by the intimal flap, along the aorta, are identified LongCaxis!view!of!transthoracic!echocardiography! showing!an!inomal!flap!(arrow)!in!aoroc!root.! Right!paraesternal!view!of!transthoracic!echo! showing!the!inomal!flap!in!ascending!aorta! (arrows),! Art!Evangelista,!2 nd!virtual!congress!in!cardiology,!argenone!federaoon!of!cardiology,!2001!

34 Aortic dissection diagnosis by transthoracic echo in;mal,flap, entry,tear, dissec;on,of, abdominal,aorta, European!Journal!of!Echocardiography!(2010)!11,!645658!

35 Aortic dissection diagnosis by transoesophageal echo

36 Intimal flap in type A aortic dissection TEE - RT3D TEE Minerva!Cardioangiol!2010;58:409C420!

37 Type B acute aortic dissection aoroc!flap! Normal!blood!flow!in!true!lumen! Low!blood!flow!in!false!lumen!thrombus!formaOon!

38 Differentiation between true and false lumen diastole! systole! European!Journal!of!Echocardiography!(2010)!11,!645658!

39 Mechanisms of AR: TEE contribution *! *!! *! * In these mechanisms it is usually possible to surgically re-suspend the native valve.

40 Intimal flap prolapse in LVOT- severe AR Figure 1. (A, B) Transthoracic echocardiograms showing an intimal flap prolapsing into the left ventricular outflow tract during diastole (arrow). (C) Color Doppler image in the apical five-chamber view shows severe aortic regurgitation (arrow). AO: Aorta; LA: Left atrium; LV: Left ventricle; RV: Right ventricle. Arch Turk Soc Cardiol 2010;38(2):

41 TEE: Arterial involvement In 10 25% cases of dissection, the intimal flap propagates retrogradely to the origin of coronary arteries (RCA: most frequently affected). Coronary involvement is suggested by left ventricular regional wall abnormalities (DD: pre-existing CAD). TEE allows direct visualization of the coronary ostia and their spatial relationship to the proximal extent of the dissection flap; proximal flow can be seen with colour Doppler. The upper oesophageal views of the aortic arch can be used to identify the origin of the head and neck vessels and assess whether flow is from the true or false lumen.

42 TEE : dissection of the descending aorta

43 Type B dissection: Entry tear / false lumen CT - IVUS Expert!Opin.!Med.!Diagn.!(2012)!6(6):529C540!

44 Reverberation artefacts Reverberation artefacts in the aortic root can occur from the walls of the left atrium and in the ascending aorta from the right pulmonary artery. The reverberation is located within the aortic lumen when the diameter of the vessel is greater than the diameter of the left atrium o o Using M-mode, the artefact can be seen to be double the distance from the probe as the original structure with movement, which is in time but twice the amplitude of the original structure. Colour flow mapping: differential flow between true and false lumens in true dissection simultaneously shows flow in both sides of linear reverberation artifacts. Ascending!aorOc!arOfact!secondary!to!le`!atrial! posterior!wall!(pai).!mcmode!shows!as!this!image! (R)!is!located!double!distance!to!the!trasnducer!of! PAI!and!with!twice!movement!amplitude.!

45 Intramural Hematoma (IMH) Dissection without tear Intact intimal layer Events leading to intramural hematoma, from rupture of vasa vasorum feeding aortic media to creation of intramedial hematoma with intact intimal layer.

46 Atypical Aortic Dissection (intramural haematoma) TEE! CT! MRI!

47 IMH two-thirds of cases are located in the descending aorta and are typically associated with hypertension the diagnosis of IMH cannot be made on clinically grounds, but by tomographic imaging in the appropriate clinical setting. Acute IMH accounts for 5 20% of all AAS, with regression in 10%, progression to classic aortic dissection in 28 47%, and a risk of rupture in 20 45% European!Heart!Journal!(2012)!33,!2635!

48 IMH Circular or semilunar thickening of the aortic wall >5 mm (>7mm*), with no dissection flap, entry tear, or false lumen. More frequent in descending than in ascending aorta Variant, precursor or coexisting with aortic dissection May contain echolucent zones no flow within Smooth luminar border Displacement of aortic plaque inward May be distributed in layers Intramural haematoma in ascending aorta (large arrows). The small arrow shows a reverberation of the aortic wall. AP: pulmonary artery. DD with CT / MRI :intraluminal thrombus or a dissection with thrombosed false lumen. In practice, the term IMH is used loosely to mean a thrombosed false lumen regardless of a small intimal defect (*) Circulation 1995;92: J Am Coll Cardiol 1994;23: European!Journal!of!Echocardiography!(2010)!11,! ! *CirculaOon!2010,121:e266Ce369!ACCF/AHA!guidelines!! Intramural haematoma in descending aorta (arrows) with a typical semilunar morphology. AOD: Descending aorta.

49 IMH: is it really dissection without a tear? High resolution ECG gated CT angiography applying multiplanar reconstractions revealed small atherosclerotic plaque ruptures at the free lateral wall or the concavity of aortic arch: cause of IMH

50 IMH

51 IMH characteristics

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53 IMH ulceraoon! Hematoma! TOE,!just!above!the!aorOc!ring:!anterior! ascending!aorta!wall!haematoma(arrow),! 0,8!cm!thick!! TOE:!Ascending!aorta,!before!the!juncOon! with!the!aoroc!arch!c!inomal!ulceraoon!in! the!depth!of!the!haematoma!

54 Natural History of IMH II: regression (medical/ TEVAR ThoracicEndoVascularAorticRepair) Spontaneous reabsortion under medical treatment of IMH less common

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56 IMH,of,the,ascending,aorta,due,to,PUA,

57 High risk imaging features of IMH

58 Penetrating Aortic Ulcer is defined as ulceration of an aortic atherosclerotic plaque penetrating through the internal elastic lamina into the aortic media Αθηρωματική,πλάκα,με,έλκος,που,διασπά,τον,έσω,χιτώνα,

59 Penetrating aortic ulcer % of acute aortic syndromes PAU occur predominantly in the descending thoracic and abdominal aorta. They occur more commonly in the elderly and there is often widespread atheromatous disease. PAU is usually a focal lesion appearing as an outpouching of the aortic wall with jagged edges. Concomitant aneurysms of the descending aorta may be found. If a PAU extends to dissection, the dissection is usually shorter, limited by neighbouring fibrosis and calcification. The flap is usually thicker, may be calcified, and is less mobile than in a true dissection

60 PAU vs atheromatous ulcers Natural history of PAU: Atheromatous ulcers are usually small, confined to the intima and do not cause symptoms, although these lesions may eventually progress to PAU. PAU extends beyond the aortic intima and therefore is seen outside the aortic lumen, usually surrounded by an IMH of variable extent, which has a smooth interface with the contrast in the lumen. Adventitial erosion may cause aneurysm formation or rupture. Rupture has been reported in up to 42% of cases. APPLIED RADIOLOGY January February 2010

61 Evolution of PAU

62 PAU causing IMH IMH,due,to,a,PUA!(arrow):! in!a!tee!shortcaxis!view!in!the!ascending!aorta!(a)!and! by,ivus!in!the!descending!aorta!(b).!! Note!the!thickening!of!the!aorOc!wall!(doubleCarrow).! Expert!Opin.!Med.!Diagn.!(2012)!6(6):529C540!

63 Iatrogenic- traumatic aortic dissection Dissection of the aorta can be caused by iatrogenic trauma during cardiothoracic bypass surgery, aortic valve replacement and various catheter-based procedures such as percutaneous transluminal coronary angioplasty, coronary stent implantation and the placement of intraaortic balloon pumps. Traumatic aortic dissection typically occurs at the isthmus of the thoracic aorta high-speed accidents trauma due to a fall from a great height Patients with aortic transection often die at the scene, but they may survive until they reach the hospital. They usually have small tears of the aortic wall with pseudoaneurysm formation TEE identifies Traumatic aortic dissection Cardiac contusion Prost-traumatic myocardial infarction Valve lesions endovascular treatment of descending aortic trauma is a better alternative to open repair and associated with lower post-operative mortality and ischaemic spinal cord complications Expert!Opin.!Med.!Diagn.!(2012)!6(6):529C540! Minerva!Cardioangiol!2010;58:409C420! European!Heart!Journal!(2012)!33,!2635!

64 Acute aortic syndromes treatment options Acute aortic syndromes (dissection or IMH) involving the ascending aorta are surgical emergencies; in selected cases, hybrid approaches of an endovascular and open combination may be considered. Conversely, acute aortic pathology confined to the descending aorta is subject to medical treatment unless complicated by organ or limb malperfusion, progressive dissection, extraaortic blood collection (impending rupture), intractable pain, or uncontrolled hypertension. European!Heart!Journal!(2012)!33,!2635!

65 AAS diagnosis o,only,the,absence,of,both,d(dimer,eleva;on,and,ecg,changes,is,considered,specific,to,rule,out, AASs, o!although!screening!transthoracic!echocardiography!(tte)!provides!vital!informaoon!(e.g.!newconset! aoroc!insufficiency,!pericardial!effusion,!or!even!visualizaoon!of!proximal!dissecoon),!addioonal!tee! interrogaoon!of!the!thoracic!aorta!is!the!logical!next!step,!or!mulodetectorcct!(mdcct)!scanning!of!the! enore!aorta!if!considered!safe.,, European!Heart!Journal!(2012)!33,!2635!

66 TTE /TEE in the diagnosis and risk stratification of AAS. TTE identifies high risk features Pericardial effusion Regional wall motion abnormalities Dilated root AR The primary aim of TEE is to identify the intimal flap, false lumen entry tear delineate the extent of aortic dissection, identify IMH or PAU. Secondary objectives are to provide important information to cardiac surgeons, such as the AR severity and its mechanism, branch involvement of coronary/head and neck, extravasation of blood Intra- peri- operative

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69 2010!American!College!of!Cardiology!FoundaOon!and!American! Heart!AssociaOon,!Inc.!Adapted!from!the!2010!ACCF/AHA/! AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM!Guidelines!for!the! Diagnosis!and!Management!of!PaOents!With!Thoracic!AorOc! Disease:!ExecuOve!Summary!(CirculaOon!2010;121:154479).!

70 IMH type A: observation vs timed surgery J!Thorac!Cardiovasc!Surg!2010;140:S92C7!

71 AAS : what a surgeon must know Minerva!Cardioangiol!2010;58:409C420!

72 The definitive imaging modality will depend upon clinical circumstances, availability of facilities, and operators: helical CT, MRI, and TEE are equally accurate and have relative strengths and weaknesses. Both CT and MRI may have time delays and practical difficulties in monitoring patients whilst in the scanner. Occasionally, multiple modalities may be needed to clarify suspicious or incongruous results.