Diseases of the aorta

Heart Disease

Braunwald

CV R4 李威廷醫師Supervisor: 李貽恆醫師

Aorta

• Intima, media, adventitia

• ascending, arch, descending

• Aortic isthmus: arch-descending junction

Aortic aneurysm

• Definition: pathological dilatation of the normal aortic lumen involving one or several segments

• Fusiform (common), saccular• Pseudoaneurysm: well-defined collection of

blood and connective tissue outside the vessel wall

Abdominal aortic aneurysm

• Age (M>55 y/o; F>70 y/o)

• Atherosclerosis

• Infrarenal arota: no vasa vasorum at media • Gene (Marfan, Ehlers-Danlos syndrome)

• Prevalence: >3%• Aneurysm rupture: 80% into left retroperitonium

cavity

Abdominal aortic aneurysm

• Pain: most common, at hypogastrium or back, not affected by movement

• Asymptom• Rupture triad: abdominal or back pain; palpable/

pulsatile abdominal mass; hypotension (<1/3 cases)

• Bruit (+/-)

• Abdomianl echo, CT, MRA, aortography

Abdominal aortic aneurysm

• Surgical indication: rupture; size >4—5 cm; expanding rapidly (>0.5 cm/year)

• Coronary angiography• Medication control: Hyperlipidemia,

hypertension, cigarette smoking

• CT follow up every 3—6 months

Thoracic aortic aneurysm

• Descending aorta > ascending aorta• Cystic media degeneration: weakening aortic

wall (elastic fiber degeneration)

• Marfan syndrome: autosomal dominant

• Ahterosclerosis

• Syphilis: ascending aorta

• Infectious aortitis / mycotic aneurysm

Thoracic aortic aneurysm

• 40% asymptom, pain• A-V shunt, superior vena cava syndrome

(mass effect), tracheal deviation, hematemesis

• CT, TEE > TTE

• Surgery: >5cm (mean expansion rate= 0.43 cm/year)• Op risk: 5%

Thoracic aortic aneurysm

• Annuloaortic ectasia: elastic fiber degeneration + aortic regurgitation

• Aortic valve replacement

Aortic dissection

• Tear in aortic intima

• Antegrade, retrograde

• false lumen, intimal flap, true lumen• Acute (2/3), chronic (1/3)

• Ascending (65%), arch (20%), descending thoracic (10%), abdominal (5%)

• Mortality: 1% per hour

Aortic dissection

• Peak: 60—70 y/o

• Hypertension, bicuspid aortic valve

• Marfan syndrome (cystic media degeneration)

• 3rd trimester pergnancy

• Blunt trauma

• IABP

• Prior cardiac surgery

Aortic dissection

• Severe tearing pain (sudden onset), CHF, syncope, CVA, ischemic peripheral neuropathy, paraplegia, cardiac arrest, sudden death

• Anterior pain only: 90% ascending

• Interscapular pain only: 90% descending

Aortic dissection

• Hypertension (descending), hypotension (ascending)

• Pseudohypotension (involving brachiocephalic vessel)

• Pulse deficit (transient), AR, neurological finding (proximal, conscious level or spinal cord ischemia)

• AMI (RCA > LCA)

• Pleural effusion (left side), cardiac tamponade

• Horner syndrome

Aortic dissection

• Calcium sign: 1.0cm (suggestive, not diagnostic)

• Normal CXR cannot exclude dissection

• EKG: LVH (1/3); absence of ST and T change; AMI (involving coronary a.)

• Initial diagnosis rate: 62%

Aortic dissection

• Mortality: 25% (<24h), 50% (1w), 75% (1m), 90% (1y)

• BP favor RA

• BP on LA if higher BP in LA than RA

• SBP: 100—120mmHg,

• mean BP: 60—75mmHg

• Pain control, beta-blocker, nitroprusside, ACEI

• Hypotension: prefer levophed

• Pericardiocentesis for cardiac tamponade

Atypical aortic dissection

Intramural hematoma: • rupture of vasa vasorum,

• aortic dissection without intimal flap, • 10% type B dissection, • failed diagnosis in aortography, • high risk for aneurysm formation, • medication (distal) or surgery (proximal)

Atypical aortic dissection

Penetrating atherosclerotic ulcer: • old, hypertension• no false lumen, • Aortography is standard• no definite treatment

Aortic atheromatous disease

Aortic atherothrombotic emboli

• Age, hypertension, DM, hyperlipidemia, vascular disease

• Most common in descending thoracic aorta• Coumadin is for high risk patients to prevent

embolic event• Post-operative stroke

Cholesterol embolization syndrome

• Cholesterol crystal from ulcerated atheromatous plaques

• “blue-toe” or “purple-toe” syndrome

• Elevated ESR & eosinophil

• Reduced complement level

• No specific therapy

Acute aortic oolusion• Infrarenal aorta at bifurcation• Saddle embolus• Af / RHD, MI, DCM, aneurysm• Bilateral leg pain, weakness, numbness, paresthesia, • Cold, cyanosis, absent pulse, diminished or absent deep

tendon reflexes• Aortogram• Heparin, transcatheter, operation • life-long anticoagulant

Primary tumor of aorta

• < 50 Cases

• Equal in thoracic and abdomen aorta

• Back pain

• Aortography, biopsy

• Prevent embolization

Peripheral artery diseases

Heart Disease

Braunwald Zipes Libby

sixth edition, 2001

CV R4 李威廷醫師Supervisor: 李貽恆醫師

Jul 1st , 2004

Peripheral artery diseases

< 60 y/o population: <3%> 75 y/o population: >20%

Peripheral artery diseases—risk factors

Peripheral artery diseases

Peripheral artery diseasesIntermittent claudication: • pain, ache, fatigue, or discomfort in the affected leg

during exercise, particularly walking (oxygen demand)• resolved with rest within few minutes• Buttock, hip, thigh• Gastrocnemius muscle is most common• Walking Impairment Questionnaire

• Arterial embolism, vasculitis / arteritis, secondary compression, lumbar sacroradiculopathy (neurogenic pseudoclaudication, standing)

Peripheral artery diseases

Rest pain• Inadequate blood flow• Skin fissure, ulceration, or necorsis• DM neuropathy or ischemic neuropathy

Peripheral artery diseases

Physical examination:

• Absent pulse distal to the stenotic site

• Bruit of the stenotic site

• Muscle atrophy, hair loss, cool skin, poor healing, pressure sore,

Peripheral artery diseases

Peripheral artery diseases

Ankle/brachial index (ABI): • SBP ratio (normal: >=1)• ABI <0.9 : 95% sensitive for PAD• ABI 05—0.8 with claudication: critical limb ischemia• ABI <0.5 or ankle BP <55mmHG: poor ulcer healing

MR angiography: 95% sensitivity and specificity

Contrast angiography

Peripheral artery diseases—treatment

Risk factor modification

Control DM, HTN, smoking cessation

Antiplatelet therapy: ticlopidine, plavix

Exercise: improve maximal walking distance than PTA

Angioplasty / stents and surgery• Trental: RBC flexibility and anti-inflammatory• Pletal: unknown• Beta-blocker: controversial

Thromboangitis obliterans

• Young smokers

• Medium and smalll vessels of the arms

• Cause unknown? Type I and III collagen

• Pain, digit ulceration, Raynaud phenomenon

• Abnormal allen test (2/3)

• Tx: Cessation smoking, prostacyclin analogue,

Acute limb ischemia

• Arterial embolism (Af)

• thrombosis with plaque ruprure

• dissection,

• trauma