Aortic Dissection

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Aortic Dissection

Introduction
Aortic dissection begins with a tear in the aorta's inner layer
Blood flows between aortic wall layers, forcing them apart
Condition is fatal without prompt treatment

Epidemiology & Diagnostic Challenge
Annual incidence: 2.9 cases per 100,000 people
Mortality increases 1-2% each hour after symptom onset
Often mimics acute coronary syndrome and stroke
High clinical suspicion required for chest, abdominal, or back pain

Classic Pain Characteristics
Sharp or tearing quality with maximal intensity at onset
Pain often radiates to back or abdomen
Severe colicky chest pain requiring IV opioids
Migrating pain follows anatomical path of aorta
Intermittent pain patterns occur as dissection progresses

Atypical Presentations
17% of cases present without pain
Common painless presentations include:
Persistent consciousness disturbance
Syncope
Focal neurological deficits
Cardiac tamponade

The CP+1 Concept
Chest Pain (CP) plus one additional symptom indicates organ involvement:
CP + Stroke
CP + Paralysis
CP + Hoarseness
CP + Limb ischemia
Consider recent chest pain in patients presenting with these symptoms (1+CP)

Physical Examination
Screen patients under 40 for Marfan Syndrome features
Listen for new aortic regurgitation murmur
Check for pulse deficits in all limbs
Document bilateral blood pressure measurements
Wide pulse pressure suggests pre-terminal state
Normal or low blood pressure does not exclude diagnosis

Diagnostic Testing
Normal chest X-ray in 33% of cases
Compare current X-ray with previous images
Calcium sign greater than 0.5cm suggests dissection
Positive troponin occurs in 25% of Type A dissections
Point-of-care ultrasound shows high specificity for intimal flap

Management Priorities
1. Immediate cardiovascular surgery consultation required
2. Pain control with fentanyl boluses (25-50 mcg)
3. Heart rate control to 60 bpm using esmolol
4. Blood pressure control to systolic 110 mmHg
5. Use nicardipine or clevidipine for blood pressure management

Critical Management Points
Never give vasodilators before heart rate control
Use higher blood pressure reading in bilateral differences
Type B dissections may require surgery with:
Malperfusion
Ongoing progression
Uncontrolled blood pressure
Perforation

Key Take-Home Messages
Maintain high suspicion for atypical presentations
Remember CP+1 and 1+CP patterns
Document physical exam findings systematically
Normal tests don't exclude diagnosis
Follow sequential management: pain → heart rate → blood pressure