Diseases of the aorta Heart Disease

Diseases of the aorta

• Heart Disease

• Braunwald

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

Peripheral artery diseases

Peripheral artery diseases—risk factors

Peripheral artery diseases

Peripheral artery diseases

• Intermittent 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