• Stanford
  • Type A
    • involves ascending Ao
    • can extend distally ad infinitum
  • Type B
    • involves Ao beyond left SCA
    • descending Ao only
• DeBakey
  • 1 = entire Ao
  • 2 = Asc Ao only
  • 3 = Desc Ao distal to LSCA
• DISSECT
  • Duration, Intimal tear, Size of dissected Ao, Segmental Extent of involvement, Clinical complications, Thrombosis of false lumen

• Genetic = collagen vascular disease
  • Marfan's syndrome (fibrillin gene mutations)
  • Ehlers-Danlos syndrome IV (collagen deficits)
  • Turner syndrome
  • annulo-aortic ectasia
  • familial aortic dissection
• Aortic wall stress
  • HTN (72%)
  • trauma
  • drugs, eg cocaine, amphetamine
  • structural = bicuspid AV
  • arteritis
  • aortic dilatation
  • pregnancy = ⬆CO
• Aortic wall resistance

• blood enters media
  • atherosclerotic ulcer, leading to intimal tear
  • disruption of vasa vasorum, leading to intramural haematoma
  • de novo intimal tear
• Can extend anywhere along the arterial tree
  • brachiocephalic trunk

• overall = extension of dissection
  • end-organ ischaemia and damage
• ascending Ao = Type A
  • Aortic root dilatation = Aortic regurgitation
  • Pericardium = Pericardial effusion / tamponade
    • proximal ascending AD ruptures into pericardium
    • avoid pericardiocentesis
      • drainage of pericardial blood may precipitate worsening leak and exsanguination
  • Coronary A = AMI
    • RCA dissection = inferior STEMI
  • carotid As = neurological / stroke
• descending Ao = Type B
  • lungs = pleural effusions = leaking aneurysm
  • retroperitoneal haemorrhage
  • spinal As = spinal cord ischaemia
  • SMA = GIT / ischaemic gut
  • renal As = AKI
  • femoral As = lower limb

• Aortic regurgitation
• HTN
• asymmetric pulses
• neurological = weakness, paraesthesia
• SVC syndrome = compression of SVC by Ao

• ECG
  • Can have inferior ST depression due to involvement of R coronary A at ostia
• TOE
  • better than TTE
  • comparable to CT and MRI for diagnostic accuracy
• TTE
  • cannot exclude AD
• Echo findings (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4396118/)
  • High risk
    • cardiac tamponade
    • severe AR
    • severe proximal aortic dilatation
    • also: RWMA, severely impaired LVEF, intimal flap
  • Normal
    • Intimal flap
    • Double lumen (true and false lumen)
    • Intramural haematoma
• CXR
  • widened mediastinum (56-63%)
  • abnormal aortic contour (48%)
• CT
  • useful screen for widened mediastinum
• Aortogram
  • was gold standard
• MRI/MRA
  • excellent sensitivity / specificity

• Type A usually require surgery
• Type B usually medically managed
  • or stent if organ damage / complicated dissection
• If Aortic root involved, may need AVR with coronary A reimplantation
• Haemodynamic goals
  • PL = adequate PL, but aggressive fluid may worsen dissection
  • HR = 60 with BB
  • RHY = sinus
  • INO = reduce with BB = ⬇shear stress on intima
  • AL = ⬇SBP 100-120 = ⬇shear stress on intima
• Beta-blockade
  • labetalol 20-80 mg then 0.5-2 mg/min
  • esmolol 0.5-1 mg/kg then 50-200 mcg/kg/min
• Analgesia
• BB intolerance / additional
  • diltiazem
  • verapamil
  • SNP
• Avoid
  • inotropes
  • hydralazine = ⬆aortic wall shear stress
  • vasoD before BB = reflex ENS+
  • pericardiocentesis in tamponade

• Pre-op
• Intra-op
  • Call for help
    • Cardiothoracic centre
    • Cardiothoracic surgeon
  • Airway
  • Breathing
    • High-flow O2
  • Circulation
    • XM blood
    • HR 60-80
    • SBP 100-120
    • BB = esmolol
    • vasoD = GTN, SNP, labetalol
• Post-op

• Pregnancy and AD
  • aggressive AB + BB
  • continuous FHR monitoring = marker of end organ perfusion
  • Type B
    • medical management + expedite delivery
    • conflict
      • anti-HT + ⬆risk PPH (GTN)
      • fetal toxic drugs = SNP
  • Type A
    • <28/40 = surgical repair + continue pregnancy
    • 28-32 = surgical repair +/- CS
    • 32-40 = simultaneous repair + CS

https://www.anesthesiaconsiderations.com/aortic-dissection

https://radiopaedia.org/cases/aortic-dissection-34

https://www.escardio.org/Journals/E-Journal-of-Cardiology-Practice/Volume-15/Cardiac-tamponade-due-to-aortic-dissection-clinical-picture-and-treatment-with-focus-on-pericardiocentesis#:~:text=Cardiac%20tamponade%20is%20the%20most,AADA%20%5B3%2C4%5D.

https://teachmeanatomy.info/thorax/organs/heart/pericardium/

https://www.healio.com/cardiology/learn-the-heart/cardiology-review/topic-reviews/aortic-dissection-ascending