Acute aortic dissection - 台中榮民總醫院

我 為 什 麼 反 對using antegrade cerebral perfusionduring operation for patient withacute type A aortic dissection

Surgical outcome for acute type A aortic dissectionSeries Year Number of PatientsAdjuncts (%) Results (%)Preoperative Shock MortalityBakhtiary et al.[97]2008 120 ACP (100) 34 5Knipp et al.[98] (NIS)2007 3013 NA NA 26Rampoldi et al.[75] (IRAD)2007 682 HCA (92) RCP (51) 31 24Apaydin et al.[99]2002 108 HCA (99) 12 25Mehta et al.[100]2002 437 HCA (87) RCP (56) 28 26Bavaria et al.[95]2001 104 HCA(100) RCP (100) 10 9.

主 動 脈 壁 的 三 層 構 造• Intima• Media 中 層內 層中 層 ( 厚 有 彈 性 )• adventitia 外 層 ( 堅 韌 )

主 動 脈 剝 離

The first report of aortic dissectionand the concept of a true and a falselumen are attributed to Shekelton inthe early 1800sThe term anurysme dissequant, ordissecting aneurysm, introduced byLaennec in 1819

Aortic dissection• Aortic dissection is bestdefined as a splitting ofthe aortic turnia mediawith extraluminal blood inthe aortic wall.• 主 動 脈 剝 離 的 定 義• 血 液 流 入 主 動 脈 壁 中 層造 成 動 脈 壁 中 層 裂 開 分 離

Aortic Dissection主 動 脈 剝 離• True lumen真 腔• False lumen 假 腔• Septum 中 隔

• Acute on chronic dissection ---rere-dissection• 再 度 ( 貳 次 ) 剝 離• Free rupture and hypovolemic shock• 導 致 主 動 脈 破 裂 , 出 血 死 亡

Dissection results in heart failure近 端 主 動 脈 剝 離容 易 導 致 急 性 心 臟 衰 竭• 1.Tamponade;• 2. Acute aortic regurgitation;• 3. Acute myocardial infarction(compromise coronary arteries)

Malperfusion syndrome

Malperfusion syndromeDissection results in organ failure,CVA, bowel gangrene, limbsischemia (compromise the branches)主 動 脈 剝 離 容 易 導 致 各 器 官 急 性 缺血 性 壞 死 及 功 能 衰 竭 ( 如 中 風 , 心 肌梗 塞 , 腸 壞 死 , 腎 衰 竭 )

CT scan: (for diagnosis of acuteaortic dissection)Noninvasive,Sensitivity of 83% to 95%Specificity of 87% to 100%

Acute aortic dissection發 作 二 週 以 內 稱 為 急 性 主 動 脈 剝 離• In untreated patients, 74% of deathsoccur within this 2-week 2period.• This is the stage when the inflammationis maximal and when the aorta is mostfriable.

Treatment for Acute aortic dissection• Currently, surgical literature, including our ownreported findings, indicates that the site of theaortic tear and thrombosis or lack of thrombosisof the false lumen do not influence either early oflate operative results.

Treatment for Acute aortic dissection• Of great importance are the extent of theaortic dissection and the diameter of theaorta, , because these determine theoperative approach, the extent of resection,and the long-term prognosis, including thelate risk of rupture.

Debakeyclassification ofaortic dissection主 動 脈 剝 離 分 類

Standford classification主 動 脈 剝 離 分 類• Type A :involving the ascending aorta.• Type B :involving all other extents beyondthe left subclavian artery.• It should be noted that aortic arch dissectionswithout involvement of the ascending aortaare now currently classified as type B.

Incidence• Probably 10 per 100,000 of the populationper annum in USA.• 2 deaths per 100,000 males and 0.8 deathper 100,000 males.• This is probably a significant underestimate.• Aortic dissection is the most common aorticdisaster.• 4.2% of all sudden deaths in men wereattributed to aortic dissection.

Predisposing factors• Hereditary and congenital factors ( 遺 傳 , 先 天 因 子 )• Pregnancy ( 妊 娠 )• Congenital aortic valve defects ( 先 天 主 動 脈 瓣 異 常 )• Coarctation of the aorta ( 先 天 主 動 脈 異 常 )• Fusiform aortic aneurysm ( 主 動 脈 瘤 )• Inflammatory diseases, infections, and hormonalabnormalities. ( 主 動 脈 發 炎 疾 病 , 內 分 泌 異 常 )

Etiology• Medial degenerative disease. 主 動 脈 壁 中 層 退 化• Hypertension : the higher the dP/dt, , the morerapid the progression of the dissection. 高 血 壓• The causes of medial degenerative disease andhypertension remain largely unknown.

Iatrogenic and traumatic factors• Aortic dissection can be precipitated byinvasive procedures:• Cardiac catheterization, aortography,arterial and aortic cannulation, coronaryartery bypass surgery, aortic valvereplacement, intraaortic balloon pump, andsimple aortic cross-clamping.• 心 導 管 及 心 臟 手 術 可 能 引 起 動 脈 剝 離

Acute aortic dissection• Lam and colleagues performed autopsystudies on 50 patients who died aftercardiac surgery and found that seven(14%) died of aortic dissection.• 心 臟 手 術 後 死 亡 者 有 14% 是 因 主 動 脈 剝離 引 起

Acute proximal aortic dissection (type A)近 端 主 動 脈 剝 離 應 立 即 開 刀 治 療• Most deaths are caused by rupture of theascending aorta to pericardium and heartfailure.• A patient with acute proximal dissection(type A) will undergo immediate repair ofthe ascending aorta, the aortic arch, orboth.

Acute type A dissection 30 days mortality近 端 主 動 脈 剝 離 30 天 死 亡 率• Surgical : 手 術 治 療 mortality 10%-25%.• Medical : 內 科 治 療 mortality morethan 50 % (75%).

Acute distal aortic dissection (type(B) B遠 端 主 動 脈 剝 離 應 先 內 科 治 療• No clinical evident complications medicaltreatment is indicated.• Conditions that may require immediatesurgical treatment : aortic rupture,preexisting aneurysm, rapid expansion ofaortic diameter, ischemia of limbs andvisceral organs, intractable pain,uncontrolled hypertension, progression ofdissection (becomes type A).

Acute type B dissection thirty-daymortality遠 端 主 動 脈 剝 離 30 天 死 亡 率• Surgical : 手 術 治 療 20%-25%.• Medical : 內 科 治 療 less than 10 %.

Survival after operation foracute type A dissection• 1 month survival rate: 80%.• 1 year survival rate: 66%.• 5 year survival rate: 46%.• 15 year survival rate: 37%• 就 算 第 一 次 手 術 成 功病 人 也 不 會 長 壽

Re-operation for aneurysm after repairof ascending aorta for type A aorticdissection第 一 次 手 術 後 幾 年 內 再 度 開 刀 的 機 會 很高

Acute aortic dissectionis the most catastrophic eventaffecting the aorta

The International Registry of Acute AorticDissection (IRAD) :began in January 1996. It initially included12 centers in 6 countries and has grown to24 referral centers in 11 countries..

The IRAD study group found an overalloperative mortality of 25% in patientswith proximal aortic dissection andnoted a significant difference betweenstable patients and those who wereunstable at initial evaluation (17%versus 31%, P < .001). One of the maindeterminants of poor outcome isneurologic status at diagnosis.

Surgical outcome for acute type A aortic dissectionSeries Year Number of PatientsAdjuncts (%) Results (%)Preoperative Shock MortalityBakhtiary et al.[97]2008 120 ACP (100) 34 5Knipp et al.[98] (NIS)2007 3013 NA NA 26Rampoldi et al.[75] (IRAD)2007 682 HCA (92) RCP (51) 31 24Apaydin et al.[99]2002 108 HCA (99) 12 25Mehta et al.[100]2002 437 HCA (87) RCP (56) 28 26Bavaria et al.[95]2001 104 HCA(100) RCP (100) 10 9.

Between January 2000 and August 2006, 120consecutive patients underwent repair of acute type Adissection. Selective antegrade cerebral perfusionthrough the right subclavian artery combined withmild systemic hypothermia (30 degrees C) was used inall patients.New permanent neurologic deficits : 5 patients(4.2%) TND : 3 patients (2.5%).The 30‐day mortality rate : 5% (n = 6).

Selective antegrade cerebral perfusion

Acute type A aortic dissectionBrachiocephalic trunk : was involved in14% of patients,Common carotid arteries : 21%,Left subclavian artery : 14%,Ileofemoral arteries : 35%.Cambria and colleagues were the first toquantify the contribution of saidcomplications to overall mortality. 1988

Review of CT aortogram(all patients with type A aorticdissection)1. 2011-08-05 to 2012-12-012. 40 patients ( out of 50 patients ).3. 31 y/o to 85 y/o; mean 55 y/o.4. Male : Female = 7 : 3 ( 28 : 12 )5. Acute dissection 32; chronic 8

Operations• Aortic valve resuspension & ascendingaorta replacement : 36.• Aortic root replacement ( modifiedBentall,s operation) & ascending aortareplacement: 4.• Aortic arch reconstruction: 4• Coronary artery bypass grafting ( CABG ):4.

Hospital stay• 7 – 15 days : 23 patients.• Less than 5 days : 4 patients.• More than 30 days : 3 patients

Major complications• Heart failure : 2 (1 myocardial infarction; 1pericardial tamponade).• Pneumonia : 4 (1 Tracheostomy, 85 y/ofemale).• Renal failure (need H/D): 2 .• Ischemic bowel syndrome : 2 .• Biliary tract infection with sepsis: 1.• Spinal cord injury : 1 (partial injury)

Mortality• 30 days mortality rate : 3/40 ( 7.5% ) (4/50 8%)• 30 days mortality rate of chronic type A aorticdissection : 0%• 30 days mortality rate of acute type A aorticdissection : 3/32 (9.4%) (4/40: 10%; 50patients)• In hospital mortality rate of acute type A aorticdissection : 5/40 ( 12.5% )

Major aortic branches involved bydissection process• Innominate artery: 22 / 40 ( 55% )• Right common carotid artery: 13 / 40 ( 33% )• Left common carotid artery: 9 / 40 ( 23% )• Right subclavian artery : 6 / 40 ( 15% )• Left subclavian artery : 9 / 40 ( 23% ).• Celiac trunk : 21 / 40 ( 53% ).• Superior mesenteric artery : 12 / 40 ( 30% )

Clamping or snaring (by tourniquet) thedissecting artery will result in rupture ofseptum during the acute stage of dissection.That will result in arterial dynamic obstructionor intraluminal thrombosis formation

Patient who is potentially suitablefor selective antegrade cerebralperfusion• Patient who had no one of the cerebralbranches (Innominate artery or left commoncarotid artery) involved by dissectionpropagation: 12/40 ( 30% ).

ConclusionOnly 30% of patients with acute type Aaortic dissection are potentially suitablefor selective antegrade cerebralperfusion during operation.