Medical Archive

Introduction

Congenital anomalies of the aorta

• Coarctation of aorta
  • Preductal coarctation (infantile type)
    • Less common. Proximal to the DA.
  • Postductal coarctation (adult type)
    • More common. Distal to the DA.
    • Enlargement of the intercostal arteries ? costal notching on the lower border of the ribs.

Aortic aneurysm

Etiology

M/c cause
Hypertension -> hyaline arteriosclerosis of the vasa vasorum
Decreased flow causes atrophy of the media.
Marfan, Ehler’s-Danlos
Risk factor: Age>65, male, smoking.

Thoracic aortic aneurysms

• Etiology and pathophysiology
  • Most TAAs (60%) involve the ascending aorta, and a minority involve the descending aorta
  • Age-related degenerative changes
    • Breakdown of structural proteins (eg, collagen, elastin)
    • Physical factors – systemic hypertension, repeated stress from the pulsating arterial wave, underlying connective tissue disease (eg, Marfan or Ehlers-Danlos syndromes)
    • Disruption of the aortic wall medial layer with loss of elasticity and consequent aortic dilation.
  • Tertiary syphilis
    • Endarteritis of the vasa vasorum results in luminal narrowing, decreased flow, and atrophy of the vessel wall.
    • Results in a ‘tree-bark’ appearance of the aorta
• Clinical manifestations
  • Usually asymptomatic until the discovery is made incidentally.
  • Some develop chest or abdominal discomfort as the TAA grows.
• Diagnosis
  • Chest x-ray
  • Chest CT scan with contrast
    • To distinguish TAA from a tortuous aorta

Treatment

Abdominal aortic aneurysms

Risk factors

• Advanced age (eg, >60)
• Male sex
• Smoking (m/i)
• Hypertension
• History of atherosclerosis or CTD.

Clinical manifestations

• ??? ???. ?? ??? rupture ??
• Proximal: upper abdominal, flank, or back pain
• Distal: lower abdominal or groin pain

Screening

• One-time abdominal duplex ultrasound in men age 65-75 who have ever smoked (ie, any lifetime exposure >100 cigarettes) or have other significant risk factors (eg, 1st-degree family history of AAA rupture)

Treatment

• Surgery indication
  • Symptomatic or >5.5cm
  • Rapid growth (6?? ? 0.5cm)
  • Saccular form rather than general fusiform
  • Open ??? ??? ?? ??

Complication 

(?? ?? ??? ??? ? ??)
Pericardial tamponade (most common cause of death),
Rupture with fatal hemorrhage
Distal embolization, thrombosis
???? ?? aortoenteric, aortocaval fistula

Acute aortic syndromes

4 Major acute aortic syndromes

• Aortic rupture
• Aortic dissection
  • Cause: HTN, cystic medial necrosis (Marfan, Ehlers-Danlos), cocaine use
  • CXR: widening of superior mediastinum, pleural effusion
  • Diagnosis: ?????, ?? CT, TEE
• Intramural hematoma
• Penetrating atherosclerotic ulcer

Clinical manifestations

• Pain
  • ??? ???? ????, ?? intrascapular. ???? ?? ??
• Blood pressure
  • >20mmHg variation in SBP between arms.
• Lab findings
  • ? D-dimer (sensitive but not specific)
• Complications
  • d/t extension
    • Carotid artery – stroke
    • Aortic valve – acute aortic regurgitation
    • Coronary artery ostia – myocardial ischemia/infarction
    • Pericardium – pericardial effusion/tamponade
    • Renal/mesenteric arteries – renal injury, abdominala pain
  • Ischemia
    • Spinal arteries – lower-extremity paraplegia & loss of crude touch/pain sensation

Diagnosis

• Stable patients
  • CT angiography with contrast
    • Contraindicated with renal insufficiency.
  • MRA with gadolinium contrast
    • If contrast CT is contraindicated
• Unstable patients
  • TEE

Treatment of aortic dissection

Stanford type A: ascending aorta  ? ??? Ix
Stanford type B: descending aorta ? ?? (BB, then vasodilator)

Medication

• HR control
  • IV ?-blocker (eg, propranolol) before starting vasodilators to prevent reflex tachycardia
  • Goal: HR <60
  • Esmolol
  • Labetalol (alpha & beta blocker) – ?? ?? ??.
• BP control
  • IV Nitroprusside – only if SBP remains above goal despite adequate ?-blockade.
  • Goal: SBP <120
• CCB
  • Nitroprusside? BB? ????? ?? ?? ??? ????? ?? ? ?? BB? ?? ?? ?..
• ??
  • Direct vasodilator (eg, diazoxide, hydralazine) – dissection ????.
  • Alpha-blocker – reflex tachycardia ???? dissection ??.
• Long-term treatment
  • ?? ??? 10YSR 60%.
  • ???? ?? ?? 6-12?? ???? enhanced CT or MRI ??? ??? ?? ??? ??

Surgery

• Indication
  • Type A, or complicated B (refractory, propagation, impending)
  • ?? ??? ??? ???? ??
  • ??? ??? ??? ??? ???? ?? ??
  • ?? ????? ??? ??? ??
  • ?? ??? ??????? ???? ??
  • Marfan syndrome??? ??
• Alternative: TEVAR (thoracic endovascular aortic repair)
  • Complicated type B ??? ???? ??.

Chronic atherosclerotic occlusive disease

• Aortoiliac occlusive disease, “Leriche syndrome”
  • Thromboembolic obliteration of abdominal aortic bifurcation
  • Symptoms
    • ??? ??? ??, symmetrical atrophy & pallor of both lower leg
    • Decreased femoral pulse
    • Impotence: erectile dysfunction
  • Treatment
    • Bypass graft from the aorta to iliac or common femoral artery: aorto-bifemoral bypass

Acute aortic occlusion

Aortitis

Takayasu’s arteritis

C356

Subclavian > Common carotid. ??? arteriotgraphy?!
????: CHF, CVA
DDx: Subclavian steal syndrome  (?? ???? ?? ???, ???? ??? ??? ?? ?) 

??: glucocorticoid

Giant cell arteritis

C356

Rheumatic aortitis

Rheumatoid arthritis – C351
Others – C355

Idiopathic aortitis

Infective aortitis