Aortic dissection resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Chetan Lokhande, M.B.B.S [2]; Pratik Bahekar, MBBS [3]

Aortic dissection resident survival guide Microchapters
Overview
Classification
Causes
FIRE
Diagnosis
Treatment Medical Surgical
Do's
Dont's

Overview

Aortic dissection is a tear in the intima of the aorta, which leads to bleeding and separation of the intima and media and creation of a false lumen. It is a medical emergency and can quickly lead to death if not managed urgently. An intimal tear or hemorrhage within the media initiates an aortic dissection. Usually patients presents with sudden onset of chest pain or back pain (tearing or sharp quality). Diagnosis is made by transesophageal echocardiography (TEE), or computed tomography angiography, or magnetic resonance imaging contrast aortography. As hypertension plays an important role in prorogation, treatment consists of an aggressive BP control. Lowering blood pressure leads to can cause reflex tachycardia and worsening of aortic dissection, thus it's important to keep heart rate under check by beta blockers, before administering any other antihypertensives. Serial imaging is done to monitor progression of a dissection. Treatment depends on anatomic location of the dissection and complications. Uncomplicated type B dissections are treated medically whereas type A dissection and complicated type B dissections are treated surgically. Aortic dissection tends to have poor prognosis, 20% patients die before reaching the hospital, and an approximately 33% die of an operative or perioperative complications.

Classification

DeBakey and Daily (Stanford) systems are the most commonly used classification is aortic dissection.

Stanford Classification

Aortic dissection is classified into two types based on involvement of involvement of the ascending aorta.

Type A

Type A includes ascending aortic dissection involving ascending aorta and/or aortic arch, and possibly the descending aorta. It includes DeBakey type I and II, and requires primary surgical treatment.

Type B

Type B includes aortic dissection involving descending aorta or the arch (distal to the left subclavian artery), without involvement of the ascending aorta. It includes DeBakey type III, and is generally treated medically as initial treatment with surgery is reserved only for complications.

DeBakey Classification

DeBakey categorizes the dissection based on location of the original intimal tear and the extent of the dissection (localized to either the ascending aorta or descending aorta, or involves both the ascending and descending aorta).

Type I

Aortic dissection starts at the ascending aorta and extends upto the aortic arch, sometimes beyond.

Type II

Aortic dissection starts and is limited till the ascending aorta.

Type III

Aortic dissection starts in the descending aorta and progresses proximally or distally.

Type III A

Aortic dissection is restricted till the descending thoracic aorta.

Type III B

Aortic dissection extending below the diaphragm.

Causes

Life Threatening Causes

Aortic dissection is a life-threatening condition and must be treated as such irrespective of the underlying cause.

Common Causes

• Atherosclerosis
• Complication of cardiac procedures
• Chest trauma
• Connective tissue disorders
• Hypertension
• Vasculitis

Click here for the complete list of causes.

FIRE: Focused Initial Rapid Evaluation

A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients in need of immediate intervention.
Boxes in salmon color signify that an urgent management is needed.

Abbreviations: AVR: Aortic valve replacement; CCU: Coronary care unit; CHF: Congestive cardiac failure; CXR: Chest X-ray; EKG: Electrocardiogram; MI: Myocardial infarction; OR: Operating room; TAVR: Transcatheter aortic valve replacement; TEE: Transesophageal echocardiogram; TTE: Transthoracic echocardiogram; HEENT: Head eye ear nose throat

Identify cardinal findings that increase the pretest probability of acute aortic dissection ❑ Chest pain or back pain or abdominal pain or inter scapular pain ❑ Sudden onset ❑ Tearing or sharp quality ❑ Increasing in intensity ❑ Syncope ❑ Perfusion deficits ❑ Refractory hypertension (decreased renal perfusion) ❑ Tensed abdomen ❑ Progressive metabolic acidosis ❑ Increasing liver enzymes

Assess the severity by the high risk features and hemodynamic instability ❑ Hypotension ❑ Cold extremities ❑ Peripheral cyanosis ❑ Mottling ❑ Altered mental status

High risk features includes If 2 or more high risk features are present, aortic dissection is confirmed by TEE and requires immediate surgical management. High risk features are as follows ❑ Chest pain described (tearing, ripping, sharp or stabbing) ❑ Sudden onset of pain and increasing in intensity ❑ Aortic disorder ❑ Aortic valve disease ❑ Recent aortic manipulation ❑ Difference in the blood pressure in both extremities ❑ Signs of shock (hypoperfusion) ❑ Pulse deficit involving carotid, femoral or subclavian arteries ❑ Diastolic murmur suggestive of aortic regurgitation ❑ Marfan's syndrome ❑ Signs suggestive of stroke

Yes

No

Assess the following things simultaneously ❑ Assess hemodynamic stability ❑ Order urgent TEE and look for the following features: ❑ Pericardial effusion ❑ Regional wall motion abnormality (RWMA) ❑ Dilated root ❑ Aortic regurgitation (AR)

Continue with the diagnostic approach below

Does the patient have hypotension

Yes

No

❑ Assess airway, breathing, and circulation ❑ Place a cardiac monitor to monitor cardiac rhythm ❑ Secure 2 large-bore intravenous lines (IVs) ❑ Monitor oxygen, respiration, blood pressure, and urine output ❑ Frequently assess, hemodynamic compromise, mental status changes, neurologic or peripheral vascular changes ❑ Monitor development or progression of carotid, brachial, and femoral bruits ❑ Obtain blood samples for, ❑ CBC, electrolytes ❑ Cardiac enzymes to rule out MI ❑ Blood group and cross match

Titrate BP between 90-120 mm Hg ❑ Control heart rate by betablockers before lowering BP by other agents, as it leads to reflex tachycardia and worsening of aortic dissection ❑ Esmolol ❑ 500 micrograms/kg intravenous initially, followed by 50 micrograms/kg/min for 4 min ❑ If necessary increase infusion up to 200 micrograms/kg/min ❑ Metoprolol ❑ 5 mg intravenously every 5-10 minutes ❑ If necessary increase up to a maximum dosage of 15 mg/total dose ❑ Substitute non-dihydropyridine calcium channel blockers or vasodilators or labetalol if betablockers are contraindicated ❑ Diltiazem ❑ 0.25 mg/kg intravenous bolus initially then 5-10 mg/hr infusion ❑ If necessary increase dose to 15 mg/hr ❑ Verapamil ❑ 0.05 to 0.1 mg/kg IV bolus ❑ Nitroprusside ❑ 0.3 to 0.5 micrograms/kg/min IV initially then increase by 0.5 micrograms/kg/min ❑ If necessary increase dose to a maximum of 15 mg/hr ❑ Labetalol ❑ 1-5 mg/min IV infusion

Consider the following contraindications before prescribing :❑ Betablockers ❑ Hypersensitivity ❑ Bradycardia ❑ Heart block ❑ Uncompensated heart failure ❑ Hypotension ❑ Asthma ❑ Severe chronic obstructive pulmonary disease ❑ Calcium channel blockers ❑ Hypersensitivity ❑ Hypotension ❑ Second- or third-degree atrioventricular block ❑ Sick sinus syndrome ❑ Left ventricular dysfunction ❑ Pulmonary congestion ❑ Nitroprusside ❑ Hypersensitivity ❑ Poor cerebral or coronary perfusion

Is aortic dissection confirmed?

Yes

No

❑ Transfer to a cardio-thoracic unit for the surgical management

Obtain a secondary imaging study, if there is a high clinical suspicion

Complete Diagnostic Approach

A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.

Characterize the symptoms: ❑ Cardiac ❑ Chest pain ❑ Tearing, ripping, sharp or stabbing* ❑ Sudden onset and increasing in intensity* ❑ Worsened by deep breathing or cough and relieved by sitting upright (suggestive of hemorrhage into the pericardial sac). ❑ Neck, throat, and jaw pain ❑ Syncope, fainting in 50% of cases (suggestive of hemorrhage into the pericardial sac causing pericardial tamponade) ❑ Anxiety ❑ Palpitation ❑ Sweating ❑ Pale skin ❑ Rapid, weak pulse ❑ Shortness of breath ❑ Peripheral edema ❑ Rapid breathing ❑ Orthopnea ❑ Extra cardiac ❑ Abdominal pain or back pain (suggestive of mesenteric ischemia) ❑ Flank pain,oliguria/ anuria (suggestive of involvement of the renal arteries causing pre-renal azotemia). ❑ Nausea and vomiting ❑ Symptoms suggestive of stroke e.g. paraplegia, numbness and tingling (suggestive of involvement of cerebral or spinal arteries) ❑ Swallowing difficulties (suggestive of pressure on the esophagus) ❑ Gastrointestinal bleeding ❑ Altered mental status ❑ Feeling of a impending doom ❑ Hemoptysis (suggestive of compression of and erosion into the bronchus) ❑ Horner's syndrome (suggestive of compression of the superior cervical ganglia) ❑ Drooping of eyelids (ptosis) ❑ Decreased or no sweating (anhidrosis) ❑ Miosis ❑ Hoarseness of voice (suggestive of compression of the recurrent laryngeal nerve) ❑ Haematemesis ❑ Stridor and wheezing (suggestive of compression of the airway) ❑ Claudication (suggestive of iliac artery occlusion) ❑ Painless dissection (15 – 55 %)(unexplained syncope, stroke or congestive heart failure (CHF))

Obtain a detailed history: ❑ Past medical history ❑ Hypertension ❑ Pheochromocytoma ❑ Family history ❑ Aortic disorder* ❑ Connective tissue disorder* ❑ Anatomic deformities ❑ Aortic valve disease* ❑ Thoracic aortic aneurysm* ❑ Coarctation of aorta ❑ Polycystic kidney disease ❑ Iatrogenic ❑ Recent aortic manipulation* ❑ Chronic steroid usage ❑ Immunosuppressive therapy ❑ Lifestyle ❑ Cocaine abuse ❑ Heavy weight lifting ❑ Trauma ❑ Genetic ❑ Marfan's syndrome* ❑ Ehlers-Danlos syndrome ❑ Turners syndrome ❑ Biscuspid aortic valve ❑ Loeys-Dietz syndrome ❑ Familial thoracic aneurysm and dissection syndrome ❑ Inflammatory vasculitis ❑ Takayasu arteritis ❑ Giant cell arteritis ❑ Behcet's arteritis ❑ Pregnancy ❑ Aortitis

Examine the patient: Vitals ❑ Pulse rate - ❑ Tachycardia (suggestive of pain, anxiety, aortic rupture with massive bleeding, pericardial tamponade, aortic insufficiency with acute pulmonary edema and hypoxemia. ❑ Wide pulse pressure (suggestive of acute aortic insufficiency) ❑ Pulsus paradoxus (suggestive of pericardial tamponade) ❑ Blood pressure ❑ Hypertension - common (suggestive of aortic dissection) ❑ Hypotension - grave prognostic indicator (suggestive of pericardial tamponade, severe aortic insufficiency, or rupture of the aorta) ❑ Kussmaul's sign - Decrease in jugular venous pressure with inspiration is uncommon ❑ Difference in the blood pressure in both extremities* ❑ Signs of shock (hypoperfusion)* ❑ Hypotension (SBP < 90 mm of Hg or drop in mean arterial pressure >30 mm of Hg) ❑ Altered mental status ❑ Cold and clammy extremities ❑ Oliguria (urine output <0.5mL/kg/hr) ❑ Pulse deficit involving carotid, femoral or subclavian artery* ❑ Increased sweating (anxiety, feeling of impending doom) suggestive of myocardial infarction HEENT examination ❑ Increased JVP (suggestive of heart failure) ❑ Hoarseness due to compression of the left recurrent laryngeal nerve ❑ Signs of miosis, ptosis and anhidrosis (suggestive of horner's syndrome) ❑ Swelling of the neck and face (suggestive of superior venacava syndrome) Cardiovascular examination ❑ Diastolic murmur (suggestive of aortic regurgitation)* ❑ Wheeze (cardiac asthma) (suggestive of CHF) ❑ Pericardial friction rub (suggestive of pericarditis) ❑ Clicks (suggestive of psuedoprolapse/true prolapse of mitral and/or tricuspid valve) ❑ Beck's triad ❑ Hypotension (suggestive of decreased stroke volume) ❑ Jugular venous distension (suggestive of decreased venous return to the heart) ❑ Muffled heart sounds (suggestive of fluid inside the pericardium) Respiratory examination ❑ Decreased movement of the chest on affected side ❑ Stony dullness to percussion (suggestive of hemothorax and / or pleural effusion ❑ Diminished breaths sounds ❑ Crackles / crepitations / rales (suggestive of acute aortic regurgitation ❑ Stridor and wheezing (suggestive of compression of the airway) ❑ Decreased vocal fremitus ❑ Pleural friction rub (suggestive of pleurisy) Abdominal examination ❑ Ascites ❑ Claudication of buttocks ❑ Absent femoral pulse Neurological examination ❑ Altered mental status* ❑ Signs of peripheral neuropathy e.g. tingling, numbness ❑ Signs suggestive of stroke* eg. focal neurological deficit, paralysis Extremity examination ❑ Pedal edema

❑ Assess the severity by counting the high risk features below marked in bold and by * ❑ Chest pain described as Tearing, ripping, sharp or stabbing* ❑ Sudden onset of pain and increasing in intensity* ❑ Aortic disorder* ❑ Aortic valve disease* ❑ Recent aortic manipulation* ❑ Difference in the blood pressure in both extremities* ❑ Signs of shock (hypoperfusion)* ❑ Pulse deficit involving carotid, femoral or subclavian arteries* ❑ Diastolic murmur suggestive of aortic regurgitation* ❑ Marfan's syndrome* ❑ Signs suggestive of stroke*

Consider alternate diagnosis: ❑ Aortic regurgitation ❑ Aortic stenosis ❑ Aortic aneurysm ❑ Atherosclerotic or cholesterol embolism ❑ Cardiac tamponade ❑ Cardiogenic shock/hypovolemic shock/hemorrhagic shock ❑ Esophageal perforation or rupture ❑ Hypertensive emergencies ❑ Musculoskeletal pain ❑ Mediastinal tumors ❑ Myocardial infarction ❑ Myocarditis ❑ Myopathies ❑ Pancreatitis ❑ Peptic ulcer disease or perforating ulcer ❑ Pleural effusion ❑ Pulmonary embolism

Low Risk ❑ No high risk features present ❑ Clinical presentation is not initially suggestive for dissection but aortic imaging may help in the absence of alternative diagnosis

Intermediate Risk ❑ Single high risk present ❑ Concerning presentation for acute dissection and requires aortic imaging if no alternate diagnosis can be reached

High Risk ❑ Two or more high risk features present ❑ Acute dissection requiring immediate surgical evaluation and expedited aortic imaging

❑ Can alternate diagnosis be ruled out

❑ Order an EKG ❑ Does EKG show ST elevation ?

Yes

No

No

Yes

❑ Consider immediate surgical consultation and do aortic imaging as soon as possible

❑ Treat accordingly

❑ Order a chest X-ray ❑ Check vitals specially blood pressure for hypotension ❑ Is there evidence of ❑ Hypotension ❑ Widened mediastinum on CXR Aortic dissection on CXR. Note is made of a wide aortic knob.

❑ Do a chest X-ray and detailed physical examination ❑ Can alternate diagnosis be ruled out If no, then order

❑ Treat like a primary acute coronary syndrome (ACS) ❑ If perfusion deficits are present then ❑ Consider immediate coronary reperfusion therapy ❑ Can the lesion be identified by coronary angiography

No

Yes

Yes Treat accordingly

No

❑ Evaluate clinical scenario for risk factors for Thoracic Aortic Disease (TAD) ❑ Advanced age ❑ Risk factor for aortic diseases ❑ Syncope

Detailed and accelerated aortic imaging

❑ Do a detailed aortic imaging for thoracic aortic disease

❑ Do aortic imaging as soon as possible ❑ Transesophageal echocardiography (TEE) (Done in an emergency or unstable patient) An echocardiogram displaying the true lumen and false lumen of an aortic dissection. In this image the intimal flap can be seen separating the two lumens. In this image color flow during ventricular systole suggests that the upper lumen is the true lumen. {{#ev:youtube|14mKjEOLNWM}} ❑ Computed tomography (CT) CT with contrast demonstrating aneurysm dilation and a dissection of the ascending aorta (Type A Stanford) ❑ Magnetic resonance imaging (MRI) (Can visualize aorta from chest to pelvis) MRI of an aortic dissection 1 Aorta descendens with dissection 2 Aorta isthmus

❑ Can aortic dissection be confirmed by imaging study

Yes

No

❑ Start appropriate therapy

❑ Obtain a secondary imaging study If there is high clinical suspicion even If the initial aortic imaging studies are negative

Treatment

Medical Treatment

Shown below is an algorithm summarizing the medical management of aortic dissection according to the 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for Diagnosis and Management of patients with Thoracic Aortic Disease.

Confirmed aortic dissection ❑ Check whether dissection occurred in ascending aorta

Yes

Consider surgical management

No

❑ Start Medical management

❑ Check Vitals ❑ Blood pressure in both arms ❑ Take the highest reading for treatment or goal therapy ❑ Is patient hemodynamically stable ?

Yes

No

❑ Control rate and pressure ❑ Beta blockers ❑ Esmolol ❑ 500 micrograms/kg intravenous initially, followed by 50 micrograms/kg/min for 4 min ❑ If necessary increase infusion up to 200 micrograms/kg/min ❑ Metoprolol ❑ 5 mg intravenously every 5-10 minutes ❑ If necessary increase up to a maximum dosage of 15 mg/total dose OR ❑ Substitute non-dihydropyridine calcium channel blockers or vasodilators or labetalol if betablockers are contraindicated ❑ Diltiazem ❑ 0.25 mg/kg intravenous bolus initially then 5-10 mg/hr infusion ❑ If necessary increase dose to 15 mg/hr ❑ Verapamil ❑ 0.05 to 0.1 mg/kg IV bolus ❑ Vasodilators ❑ Nitroprusside ❑ 0.3 to 0.5 micrograms/kg/min IV initially then increase by 0.5 micrograms/kg/min ❑ If necessary increase dose to a maximum of 15 mg/hr ❑ Labetalol ❑ 1-5 mg/min IV infusion ❑ Goal heart rate should be 60 beats per minute ❑ Goal systolic BP 90-120 mm of Hg ❑ Pain control ❑ Use Opiates ❑ Morphine sulphate ❑ 2-5 mg intravenously every 5-30 minutes or as needed

❑ Type A dissection ❑ Is a surgical emergency, do an expedited surgical consultation Surgery is relatively contraindicated in hemorrhagic stroke ❑ Maintain euvolemic status ❑ Intravenous fluid replacement ❑ Maintain mean arterial pressure (MAP) of 70 mm of Hg ❑ Rule out the following complications using imaging studies: ❑ Pericardial tamponade ❑ Rupture of aorta ❑ Aortic insufficiency ❑ Myocardial infarction Stanford A type dissection

❑ Type B dissection ❑ Uncomplicated dissection are treated medically ❑ Intravenous fluid replacement ❑ Maintain mean arterial pressure (MAP) of 70 mm of Hg ❑ Start vasopressors, if the patient remains hypotensive ❑ Complicated aortic dissection is treated surgically ❑ Leaking dissection ❑ Rupture ❑ Malperfusion to a vital organs ❑ Refractory hypertension (decreased renal perfusion) ❑ Tensed abdomen ❑ Progressive metabolic acidosis ❑ Increasing liver enzymes ❑ Rupture in the pericardial sac(rare) ❑ Beck's triad (cardiac tamponade) ❑ Imaging studies to find out contained rupture ❑ Perform Transthoracic echocardiogram (TTE) to assess cardiac function Stanford B type dissection

❑ Can the cause of hypotension respond to surgical management

❑ Monitor vitals closely ❑ Maintain systolic BP <120 mm of Hg

No

Yes

Consider surgical management

Yes

No

❑ Check if dissection involves ascending aorta

Yes

No

❑ Control blood pressure ❑ Intravenous vasodilator

❑ Monitor vitals closely ❑ Maintain systolic BP <120 mm of Hg

❑ Check for any complications which might require surgery ❑ Malperfusion ❑ Progressing dissection ❑ Expansion of aortic aneurysm ❑ Uncontrolled or refractory hypertension

Yes

❑ Consider surgical management

No

❑ Switch to oral medications ❑ Betablockers ❑ Antihypertensive regimen ❑ Follow up in the outpatient

Surgical Treatment

Shown below is an algorithm summarizing the surgical management of aortic dissection according to the Guidelines for Diagnosis and Management of patients with Thoracic Aortic Disease.

❑ Imaging study confirms aortic dissection ❑ Check whether dissection occurred in ascending aorta

No

Yes

❑ Assess suitability for surgery ❑ Patient stable for pre-op testing?

No

Medical management

Yes

❑ Age > 40?

No

Yes

❑ Assess need for pre-operative coronary angiography ❑ Known CAD? ❑ Significant risk factors for CAD?

No

Yes

❑ Perform angiography Is significant CAD detected on angiography?

No

Yes

❑ Plan for CABG at the time of aortic dissection repair

❑ Perform urgent operative management

❑ Perform intra-operative assessment of aortic valve by Transesophageal echocardiography (TEE) for presence of one of the following: ❑ Aortic regurgitation ❑ Dissection of aortic sinuses

No

Yes

❑ Perform graft replacement of ascending aorta ± aortic arch

❑ Perform graft replacement of ascending aorta ± aortic arch ❑ Consider repair/replacement of aortic valve

Do's

History and Examination

• For pre-test risk determination include information about:
  • Medical History
  • Family history and ask specifically for family history of aortic dissection or thoracic aneurysm
  • Pain history
• Do a detailed physical examination to identify findings for certain high risk conditions like:(class I, level of evidence B)
  • Marfan's syndrome
  • Loeys-Dietz syndrome
  • Ehlers-Danlos syndrome
  • Turner's syndrome
  • Connective tissue disorder
• Check for genetic mutations predisposing to dissection:(class I, level of evidence B)
  • Fibrillin 1 (FBN1)
  • Transforming growth factor, beta receptor I (TGFBR1)
  • Transforming growth factor, beta receptor II(TGFBR2)
  • Alpha-actin-2(ACTA2)
  • Myosin-11 (MYHH11)
• Ask about recent aortic or surgical or catheter manipulation.(class I, level of evidence C)
• Ask in detail about the pain. Include the following: (class I, level of evidence B)
  • Onset of pain whether abrupt or instantaneous
  • Severity of pain
  • Quality of pain whether ripping, tearing,stabbing or sharp.
• Check for the following features on examination:(class I, level of evidence B)
  • Pulse deficits
  • Blood pressure (systolic) difference of above 20 mm of Hg in limbs
  • New onset aortic regurgitation features
  • Focal neurological deficits
• Patients less than 40 years of age and presenting with sudden onset chest, abdominal or back pain should be evaluated for high risk conditions.
• Patients presenting with features of syncope along with features of dissection should have a detailed neurological examination and cardiovascular examination to rule out pericardial tamponade and other neurological deficits.(class I, level of evidence C)

Screening Tests

• Do a transesophageal echo (TEE) in the emergency room. This is the preferred approach. If the patient is hemodynamically unstable, then a transesophageal echo can be performed in the operating room after the patient has been induced and is being prepared for surgery.
• Do a MRI only if:
  • A patient who has chronic chest pain who is hemodynamically stable
  • A chronic dissection
• Do an EKG when patients presents with symptoms of dissection.(class I, level of evidence B)
• Treat the patient as an acute cardiac event, if ST elevation is present in EKG then, unless the patient has high risk factors for acute dissection.
• Perform coronary angiography, followed by thrombolysis or percutaneous coronary intervention, if EKG shows ST elevation with no dissection features.
• Do order a X-ray for all patients with intermediate risk and a low risk to rule out alternate diagnosis.(class I, level of evidence C)
• Evaluate high risk patients by transesophageal echocardiogram, computed tomography or magnetic resonance imaging to rule out dissection.(class I, level of evidence B)
• Obtain a secondary imaging study, if the initial aortic imaging studies are non conclusive, and there is a high clinical suspicion.class III, level of evidence C

Initial Management

• Medical management should be aimed at decreasing aortic wall stress.(class I, level of evidence C)
• Titrate beta blocker to maintain heart rate of 60 beats/ minute.(class I, level of evidence C)
• Use nondihyropyridine calcium channel blockers to control rate, if beta blockers are contraindicated.(class I, level of evidence C)
• Use angiotensin converting enzyme and other vasodilators to maintain end organ perfusion, if BP remains above 120 mm of Hg, after medical treatment.(class I, level of evidence C).

Definitive Management

• Do a definitive aortic imaging study, if chest X-ray demonstrates widened mediastinum.
• Aim to curtail heart rate less than 60 beats/minute and systolic blood pressure between 90 and 120 mm Hg.
• Use Sodium nitroprusside as the first line for the treatment of hypertension. Nicardipine, nitroglycerin and fenoldopam can also be used.
• Use esmolol in asthma, congestive heart failure or chronic obstructive pulmonary disease.
• Use labetalol to maintain heart rate and blood pressure, it prevents usage of another vasodilator.
• Do a pericardiocentes for pericardial bleeding and dissection related hemopericardium.
• Do a plasma smooth muscle myosin heavy chain protein, D-dimer and high sensitive C-reactive protein to rule out alternate diagnosis.
• Order a surgical consultation for all patients once diagnosed with aortic dissection. This applies to patients presenting with dissection at any location. (class I, level of evidence C)
• Do an emergent repair in acute dissection of ascending aorta to prevent complications like rupture.(class I, level of evidence C)
• Consider surgical repair for all type A dissections as they involve the aortic valve. Ascending aortic dissections often involve the aortic valve, which having lost its suspensory support, telescopes down into the aortic root, resulting in aortic incompetence. This needs re-suspending to re-seat the valve and repair / prevent coronary artery injury. The area of dissection is removed and replaced with a dacron graft to prevent further dissection from occurring.
• Suspect malperfusion in type B aortic dissection, if following sings are present, refractory hypertension (decreased renal perfusion), tensed abdomen, progressive metabolic acidosis, increasing liver enzymes(impaired perfusion of truncus coelicaus, mesenterial arteries).
• Consider medical management for type B dissections, unless there is leaking, rupture or compromise to other organs, e.g. kidneys and life threatening conditions like perfusion deficit, dissection enlargement, aneurysm enlargement or blood pressure refractory to treatment.(class I, level of evidence C)

Dont's

• Don't delay aortic imaging even if chest x-ray is negative (class III, level of evidence C).
• Don't use beta blocker in patients having aortic regurgitation as they may block the tachycardia caused by compensation.
• Don't use vasodilator before heart rate is controlled otherwise there would be reflex tachycardia which would increase the stress on aorta and worsening the dissection.
• Hemorrhagic stroke is a relative contraindication to urgent surgical intervention done for type A tears, as intraoperative heparinization and restoration of cerebral blood flow can worsen ongoing stroke outcomes.

References