Aortic Dissection and Aneurysms Presented by Dr. Daniel Kranitz

Aortic Dissection and Aneurysms

• Presented by Dr. Daniel Kranitz

• Prepared by Mary Edwards

• September 27, 2005

• Tintanalli Chapter 58, Pages 404-409

Abdominal Aortic Aneurysms (AAA)

• Risk factors

• Elderly (>60)
• Familial trend (18% with 1° relative)
• Connective Tissue D/O (Marfan’s)
• Other aneurysms
• Atherosclerosis (HTN, Lipids, smoking, DM)

AAA

• Pathogenesis

• Intima infiltrated by atherosclerosis and thinned media.
• Possible intraluminal thrombus and adventitia infiltrated by inflammatory cells

AAA

• Average rate of growth 0.25-0.5 cm per year.

• Larger aneurysms extend more rapidly than smaller ones. (LaPlace law)

AAA

• Clinical Features

• Syncope (10-12%)
• Back and/or Abdominal Pain –severe and abrupt, ripping or tearing sensation (50%)
• Shock –intraperitoneal rupture, massive blood loss
• Sudden death

AAA

• Physical Exam

• Pain on palpation or not
• Retroperitoneal hematoma
• Cullen sign (periumbilical ecchymosis)
• Grey-Turner sign (flank ecchymosis)
• Scrotal hematoma or inguinal mass (blood dissecting to these areas)
• Iliopsoas sign
• Femoral nerve neuropathy

AAA

• Found aneurysms refer to follow up

• >5cm diameter –increased chance of rupture

• <5cm –decreased chance of rupture

• Symptomatic aneurysms of any size = Emergency!!

AAA

• Diagnosis

• Includes differential diagnoses of syncope, abd pain, CP, back pain and shock.
• If with combo of two or more think aortic dz.

AAA

• Radiologic Evaluation

• Should not delay operative treatment!!

• Plain abd film (calcified bulging)
• US (bedside, up to 100% sensitive, not reliable to detect rupture)
• CT (with IV contrast only if stable)
• MRI

AAA

• ED Treatment

• Urgent surgical consult
• Make diagnosis & assist rapid transfer to OR
• 2 large bore IVs
• Cardiac Monitor
• O2
• ? Blood transfusion
• IV fluid resuscitation –controversial amount b/c too much can be harmful

• RADIOGRAPHIC STUDIES ONLY IF UNLIKELY TO HAVE RUPTURED AAA!!!

AAA

• ½ of patients with ruptured AAA who reach the OR die!

A Bit About Thoracic Aortic Aneursym

• Presenting symptoms include esophageal, tracheal, bronchial, or even neurologic disorders.

• If it erodes to adjacent structures it is immediately fatal!!

Aortic Dissection

• Pathogenesis

• Prominent cause of sudden death
• Presents with severe abd., chest, and back pain
• Violation of intima that allows blood to enter media and dissect b/w intimal and adventitial layers
• Common site is ascending aorta at ligamentum arteriosum

Aortic Dissection

• Common presenting groups

• >50 yoa with HTN
• 2/3 male
• Marfan’s syndrome
• Congenital heart disease
• Pregnancy

Aortic Dissection

• Stanford Classification

• Type A -involves ascending aorta
• Type B –involves descending aorta

• DeBakey Classification

• Type I –ascending, arch & descending aorta
• Type II –ascending only
• Type III –descending only

Aortic Dissection

• Clinical Features

• >85% abrupt, severe pain in chest or b/w scapula
• 50% ripping or tearing
• Pain in anterior chest –ascending aorta (70%)
• Back pain (less common) –descending aorta (63%)
• If dissection into carotid classic neuro symptoms

Aortic Dissection

• Clinical Features

• 40% with neurologic sequelae (ex. paraplegia)
• Nausea, vomiting, diaphoresis
• Most have sense of impending doom!

Aortic Dissection

• Physical Exam

• Usually normal heart and lung exam
• May have aortic insufficiency
• <20% with decreased radial, femoral or carotid pulse
• HTN
• Tachycardia
• Hypotension

Aortic Dissection

• Physical Exam

• Pericardial tamponade (muffled heart tones, JVD, pulsus paradoxus)
• Hoarseness (compression of recurrent laryngeal nerve)
• Horner’s Syndrome (compression of superior cervical sympathetic ganglion)

Aortic Dissection

• Diagnosis

• Ischemic end-organ manifestation such as MI, pericardial dz, pulmonary d/o, stroke, SCI, musculoskeletal dz of extremities, intraabdominal ischemia.
• Can change location with time as dissects.

Aortic Dissection

• Thoracic Dissection

• 90% have abnormal CXR
• Widened mediastinum
• Abnormal aortic contour
• Pleural effusion
• Deviation of trachea, mainstem bronchi, or esophagus
• Intimal calcium visable & distant from edge (calcium sign)

Aortic Dissection

• Diagnosis

• CT
• 83-100% sensitive
• 87-100% specific
• Use spiral CT with IV contrast
• Will not give anatomic details of arterial branches or aortic valve competence.
• Modality of choice in unstable patient

Aortic Dissection

• Diagnosis

• Angiography
• “Gold standard”
• Shows all anatomy and involvement
• 94% specific
• 88% sensitive
• TEE
• 97-100% sensitive
• 97-99% specific
• Esophageal dz contraindication

Aortic Dissection

• In contrast to ruptured AAA, SUSPECTED DISSECTIONS MUST BE CONFIRMED RADIOLOGICALLY PRIOR TO SENDING TO OR!!!

Aortic Dissection

• ED Treatment

• Treat hypertension
• -blocker
• Esmolol 500g/kg IV bolus over 1 minute then 50-150 g/kg minute
• Metoprolol 5mg q2min x3 IV then 2-5mg/hr
• Propranolol 20mg IV then 40mg, 8-mg q10min to 300mg total
• Calcium channel blocker if -blocker contraindicated

Aortic Dissection

• ED Treatment

• Vasodilator
• Nitroprusside 0.3 g/kg/min IV
• Surgery
• OR for ascending aortic dissection
• Descending aortic dissection worse surgical risks –controversial for repair

• Any Questions????

Questions

• 1. A patient with a suspected aortic dissection should be immediately tranferred to OR without radiographic studies.

• A. True

• B. False

• 2. Females are more likely than males to develop aortic dissection.

• A. True
• B. False

• 3. Dissection of the ascending aorta only is DeBakey classification

• A. Type I
• B. Type II
• C. Type III
• D. Type A
• E. Type B

• 4. Patients with a ruptured AAA can present with all of the following symptoms except

• A. Shock
• B. Syncope
• C. Sudden death
• D. Nausea and vomiting
• E. Headache

• 5. Which of the following radiologic modalities is considered the “gold standard” for diagnosing an aortic dissection?

• A. CT
• B. MRI
• C. TEE
• D. Angiography
• E. CXR

Answers

• 1. B

• 2. B

• 3. B

• 4. E

• 5. D