Aortic Dissection PDF

AORTIC DISSECTION QUICK ANATOMY OF THE AORTA Made up of 3 parts: Ascending Aorta Arch of Aorta Descending Aorta --> Abdominal Aorta The Aortic Wall comprises of 3 layers: Tunica Intima (endothelial Cells) Tunia Media (smooth muscles) Tunia Adventia/externa (connective tissue)  PA...

AORTIC DISSECTION QUICK ANATOMY OF THE AORTA Made up of 3 parts: Ascending Aorta Arch of Aorta Descending Aorta --> Abdominal Aorta The Aortic Wall comprises of 3 layers: Tunica Intima (endothelial Cells) Tunia Media (smooth muscles) Tunia Adventia/externa (connective tissue)  PATHOPHYSIOLOGY OF AORTIC DISSECTION (AD) Acute Aortic Syndrome is a group of diseases that inlude AD, Penetrating Aortic Ulcer and Intramural Hematoma AD is a tear in the intimal layer of the aortic wall which allows blood flow inbetween the Intima and Media forming a FALSE LUMEN Tear is typically caused by chronic exposure to high pulsatile pressures and shear stresses. This false lumen can widen either distally (Anterograde towards Illiac Artery) or proximally (Retrograde towards root of Aorta)  CLASSIFICATION OF AORTIC DISSECTION Standford Classification: (useful for treatment) Type A - tear that can originate from any part of the aorta but must involve the ascending Type B - all other dissections that dont involve the ascending aorta Debakey System: Type 1 - involves ascending, arch and descending Type 2 - orginates and is limited to ascending Type 3a - involves desecnding and extends up to diaphragm Type 3b - involves desecending and extends past diaphragm Note the overlap of Type A with Type 1 and 2 RISK FACTORS OF AORTIC DISSECTION (AD) Hypertension and abrupt changes in BP (lifting/cocaine etc) Connective Tissue Disorders (Marfan Syndrome) Turner’s Syndrome (seen only in biological women) Pre-exsiting Aortic Aneurysm Atherosclerosis Catheterization for coronary/valve diseases (iatrogenic) Bicuspid Aortic valve Coarctation of Aorta Trauma Biological Male Family History  CLINICAL PRESENTATION OF AORTIC DISSECTION Clinical Triad: Sudden Tearing chest/back/abdominal pain Reduced/abscent pulses (eg carotid) and/or blood pressure differences (>20) in both arms Mediastinal/Aortic Widening on CXR Type A: More often anterior chest pain Type B: Aortic valve damage causing regurg Pain located in the back and can radiate Cardiac Tamponade + hypotension to the abdomen Acute Coronary Syndrome Reduced urinary output Hemotyposis (hemothorax if ruptured) Lower extremity loss of pulses Upper extremity loss of pulses focal neuro deficits due to spinal Focal neuro deficits (hemiplegia, syncope ischemia etc) secondary to cerebrovascular ischemia Note: Type A includes ascending Aorta tears due to compression of the relevant artery that propergate towards the abdomnen Horner’s Syndrome therefore signs of Type B can also be seen Hemodynaic Instability seen here  DIAGNOSING AN AORTIC DISSECTION Bed Side: ECG - look for Acute coronary Syndrome as a complication or a differntial If Hemodynamically unstable - Transesophageal Echo (TEE) --> looking mainly at the aortic root and ascending aorta Bloods: Baseline Bloods (FBC, EUC, LFTs, Coags) Group and Hold Troponin (ACS) D-Dimer - rule out AD Imaging: If Hemodynamically Stable - CT Angio --> can apprecaite whole aorta CXR - see Mediastinal/Aortic Widening or loss of aortic knuckle or pleural effsuions  EVALUATING RISK OF AORTIC DISSECTION Aortic dissection detection risk score (ADD-RS) Takes into account high risk: Clinical conditions like aortic valve disease and marfan syndrome Pain features: ripping pain with abrupt onset Examination findings like focal neuro deficits, hypotension It is scored out of a total of 3 and 1 point is given for each category if any of the findings/symtoms is seen. MANAGMENT AND STABILISATION OF AORTIC DISSECTION 2 Large bore IV (+ vasopressors if hypotensive) Supplementary 02 Monitor HR and maintain