Aortic dissection

Case presentation

50 yo man BIBA at 0230 with 3 hours of dull non-radiating central chest pain.

En route, administered O2, 300mg Aspirin, 10mg Morphine and 10mg Metoclopramide

Pain free on arrival.

Previously well

No positive risk factors for IHD or PE

No regular medication or other drug

use

No trauma or recent infections

No prior episodes of chest pain

Vomited twice at home, and described as clammy and pale on arrival of ambulance, with BP 90/60 supine.

On arrival

Pale

Temp 37 HR 60

BP 60/40mmHg RR 14

O2 sat100% (3L/min)

GCS 15/15

Equal radial pulses4/6 Systolic murmurLungs clear to auscultation

ECG

Initial treatment

IV fluid 1L Normal saline statColour improved, BP to 90/60 mmHg, Pain free

Early investigations:Trop T < 3 ng/L (N < 15)

CXR

Course

2nd ECG normal and Trop T < 3 at 6 hours post onset of pain

2nd litre of saline running, BP still 90/60mm/Hg, HR 60/min, with normal peripheral perfusion

BP both arms the sameChest pain “2/10”

Decision to order CT angiogram of chest

Intimal tear / flap of dissection in aortic arch

7.10AM Patient transferred to the OT for repair of the type A dissection and the aneurysmal dilatation of aortic root.

Aortic Dissection

Relatively uncommon (2.6-3.3/100 000 person- years)

Initial event in aortic dissection is a tear in the aortic intima.

Propagation of the

dissection may be

1. Proximal (retrograde)

2. Distal (antegrade)

Complications

Aortic valve injury with regurgitation

Pericaridal tamponade

End organ ischemia, examples include syncope, CVA, mesenteric or renal ischaemia.

Risk factors for aortic dissection

Advancing ageMale sex 2:1 (Female – pregnancy)Systemic hypertensionPre-existing aortic aneurysmAtherosclerosis

Risk factors for under age 40

Collagen vascular disorders VasculitisBicuspid aortic valveAortic coarctationTurners syndromeMarfan syndrome Prior aortic valve surgeryInstrumentationTraumaHigh intensity weight lifting or other exerciseCocaine

Classification

Stanford Type A –ascending AortaType B – all other types / sites in aorta

DeBakeyType I – Originates in ascending aorta, propagates at least to the aortic arch and often beyond it distally.

Type II – Originates / confined to the ascending aorta.

Type III – Originates in descending aorta, rarely extends proximally but will extend distally.

Diagnosis

Routine bloods – non diagnostic D-dimer < 500ng/ml unlikely to be dissection

History Anterior chest pain in ascending aortic

dissection Severe sharp or tearing posterior chest or

back pain when the dissection progresses distal to the subclavian artery

Pain can associated with

Syncope Stroke MIHeart failureEnd organ ischemia (splanchnic, renal, extremity or spinal cord ischaemia)

Hypertension common with type BHypotension

Diagnosis of aortic dissection depends

upon demonstration of the dissection on

imaging studies

CXRCTMRITEE / TTE

CT

Immediate management

Maintain airway, good supportive careTreat hypotension / hypertension – aim for MAP 60-70

Beta blockerseg esmalol propranolol, labetalol

Vasodilators Na nitroprussideCalcium channel blockerseg verapamil, diltiazem

Management

Type A – Surgical

Type B – Surgical/medical