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INTERNAL MEDICINE:
Vascular Diseases of the Extremities
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -Definition: stenosis or occlusion in the aorta or
arteries of the limbs -atherosclerosis is the leading cause of PAD in
patients >40 years old -other causes: -thrombosis -embolism -vasculitis -fibromuscular dysplasia -entrapment -cystic adventitial disease -trauma
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-the highest prevalence of atherosclerotic PAD occurs in 60s-70s
-Risk Factors:
-cigarette smoking -hypercholesterolemia
-DM -hypertension
-hyperhomocysteinemia
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: Pathology: -stenosis or occlusion are usually LOCALIZED TO
LARGE AND MEDIUM SIZED VESSELS -include the ff: 1. Atherosclerotic plaques w/ calcium deposition 2. Thinning of the media 3. Patchy destruction of muscle & elastic fibers 4. Fragmentation of the internal elastic lamina 5. Thrombi composed of platelets and fibrin
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -Primary sites of involvement: 1. femoral and popliteal arteries 2. tibial and peroneal 3. abdominal aorta and iliac arteries *atherosclerotic lesions occur preferentially at : a.) arterial branch points b.) sites of increased turbulence c.) altered shear stress d.) site of intimal injury
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -S/Sx: -50% are asymptomatic -MOST COMMON SYMTPOM: INTERMITTENT
CLAUDICATION -Definition: pain, ache, cramp, numbness or
sense of fatigue in the muscles, occurs during exercise and relieved by rest, common in lower than upper extremities
-the site of claudication is DISTAL to the location of the occlusive lesion e.g. calf claudication- femoral/popliteal lesion
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -S/Sx: -pts may complain of rest pain commonly at night when legs
are horizontal and improve when legs are on dependent position
-absent/decreased pulses distal to obstruction -bruits -muscle atrophy -hairloss -thickened nails -smooth and shiny skin -decreased skin temperature -pallor/cyanosis
ISCHEMIC NEUROPATHY: -numbness -hyporeflexia SEVERE ISCHEMIA: -edema
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -Non-invasive Testing *History and physical examination are often sufficient to
establish the diagnosis of PAD 1. Arterial Pressure -placement of sphygmomanometric cuffs at the
ankles and use of a Doppler device to auscultate or record blood flow from the dorsalis pedis and posterior tibial arteries
-NORMAL arms and legs SBP are equal, but ANKLE PRESSURE may be slightly HIGHER DUE TO PULSE-WAVE AMPLIFICATION
-SBP in ankle is DECREASED IN STENOSIS
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-Non-invasive Testing
2. Ankle:Brachial Index
-NORMAL: > 1.0
-PAD: < 1.0
-Severe ischemia: < 0.5
3. Duplex Ultrasonography
-image and detect stenotic lesions in native arteries and bypass grafts
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -Non-invasive Testing 4. Treadmill Testing / Stress test -allows physician to assess functional limitation
objectively -decline in ABI immediately after exercise
provides further support for the Dx of PAD 5. Magnetic Resonance Angiography, CT
angiography, contrast angiography -not for routine testing but done prior to
revascularization
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-Non-invasive Testing
6. Other tests
-segmental pressure measurements
-pulse volume recordings
-doppler flow velocity waveform analysis
-transcutaneous oximetry
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-Prognosis:
-influenced primarily by coexistence of:
1. coronary artery disease
2. cerebrovascular disease
-most is highest with the most severe PAD
-It can be worse in patients who continue to smoke cigarette and those with DM
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-Rx:
1. Risk factor modification and antiplatelet therapy should be intiated to improve cardiovascular outcomes
2. Cessation of cigarette smoking
-counseling and adjunctive drug therapy with nicotine patch, bupropion or varenicline increases cessation rates and reduces recidivism
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -Rx: 3. ACE inhibitors – symptomatic PAD 4. B-adrenergic blockers – HTN with coexistent CAD -reduce post revascularization complications 5. Statins NCEP – LDL cholesterol <100mg/dl 6. Clopidogrel -inhinits platelet aggregation via its effect on
ADP-dependent platelet fibrinogen binding -more efficient than aspirin in decreasing M&M
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-Rx:
7. Cilostazol – phosphodiesterase inhibitor with vasodilator and antiplatelet properties, increases claudication distance
8. Pentoxifylline – xanthine derivative; decreases blood viscosity to increase red cell flexibility, increasing blood flow to the microcirculation and enhancing tissue oxygenation
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE: -Rx: *WARFARIN not used in patients with CHRONIC PAD 9. Supportive measures -meticulous care of feet -shock blocks under the head of the bed and canopy
over the feet -exercise regularly and at progressively more
strenuous levels (30-45 min session, 3-5 times/wk for 12 weeks)
-advise to walk until near maximum caludication discomfort occurs, then resting until the symptoms resolve before resuming ambulation
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
PERIPHERAL ARTERIAL DISEASE:
-Rx:
10. Revascularization
-indicated for pts with disabling, progressive, or severe symptoms of intermittent claudication despite medical therapy or those with critical limb ischemia
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
FIBROMUSCULAR DYSPLASIA: -Definition: -hyperplastic disorder affecting medium-sized and
small arteries -common in FEMALES -usually involves RENAL and CAROTID arteries but
can affect extremity vessels, most common are the ILIAC ARTERIES
- “string of beads”” appearance
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
FIBROMUSCULAR DYSPLASIA:
-Histologic classifications:
1. Intimal Fibroplasia
2. Adventitial Hyperplasia
3. Medial Dysplasia
a. medial fibroplasia
-MOST COMMON
b. perimedial fibroplasia
c. medial hyperplasia
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
FIBROMUSCULAR DYSPLASIA:
-S/Sx:
1. Claudication
2. Rest pain
-Tx:
1. Percutaneous Transluminal angiography (PTA)
2. Surgical reconstruction
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
FIBROMUSCULAR DYSPLASIA:
-S/Sx:
1. Claudication
2. Rest pain
-Tx:
1. Percutaneous Transluminal angiography (PTA)
2. Surgical reconstruction
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
THROMBOANGITIS OBLITERANS / BUERGER’S DISEASE:
-Definition:
-an inflammatory occlusive vascular disorder involving small and medium-sized arteries and veins in the distal upper and lower extremities
-common in men <40 years
-with definite relation to cigarette smoking
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
THROMBOANGITIS OBLITERANS / BUERGER’S DISEASE:
-Pathogenesis: INITIAL STAGE: polymorphonuclear leukocytes
infiltrate arterial and venous walls internal elastic lamina is preserved but
inflammatory thrombus develops Mononuclear cells, fibroblasts and giants cells
replace the neutrophils LATER STAGES: Perivascular fibrosis, organized
thrombus, recanalization
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
THROMBOANGITIS OBLITERANS / BUERGER’S DISEASE:
-S/Sx:
-TRIAD
1. Claudication of affected extremity
-affects distal vessels (calves, forearms)
2. Raynaud’s phenomenon
3. Migratory superficial vein thrombophlebitis
-trophic nail changes
-reduces/absent pulses on ulna, radius, tibia
-smooth, tapering segmental lesions in the distal vessels
-collateral vessels at site of occlusio
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
THROMBOANGITIS OBLITERANS / BUERGER’S DISEASE:
-Dx:
-excisional biopsy and pathologic examination of the involved vessel
-Rx:
-no specific treatment EXCEPT ABSTENTATION FROM TOBACCO
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ACUTE ARTERIAL OCCLUSION:
-Definition:
-results in the sudden cessation of blood flow to an extremity
-TWO PRINCIPAL CAUSES:
1. embolism
2. thrombus in situ
-paradoxically, may originate from a venous thrombus that entered the systemic circulation via a patent foramen ovale or septal defect
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ACUTE ARTERIAL OCCLUSION:
-EMBOLISM
-most common sources: heart, aorta, large arteries
-emboli tend to lodge at vessel bifurcation because the vessel caliber decreases at these sites
-in the lower extremities, emboli lodge more frequently in femoral A, iliac A, aorta, popliteal A and tibioperoneal A.
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ACUTE ARTERIAL OCCLUSION:
-THROMBUS IN SITU
-occurs more frequently in atherosclerotic vessels at the site of an atherosclerotic plaque or aneurysm and in arterial bypass grafts
-may complicate arterial punctures and placement of catheters
-associated with polycythemia and hypercoagulable disorders
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ACUTE ARTERIAL OCCLUSION:
-S/Sx:
-severe pain, paresthesia, numbness, coldness develop in the involved extremity within 1 hour
-paralysis may happen in severe ischemia
-loss of pulses distal to occlusion
-pallor/cyanosis
-hyporeflexia/areflexia
-weakness and muscle stiffening
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ACUTE ARTERIAL OCCLUSION:
-Dx:
1. Arteriography
-useful in confirming Dx and demonstrating location and extent of occlusion
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ACUTE ARTERIAL OCCLUSION: -Rx: 1. Heparin -to prevent propagation of clot 2. Throboembolectomy/Arterial bypass procedure 3. Intraarterial thrombolytic therapy with
recombinant tissue plasminogen activator or urokinase
*meticulous observation for hemorrhagic complications is required during intraarterial thrombolytic therapy
VASCULAR DISEASES OF THE EXTREMITIES – Arterial Disorders
ATHEROEMBOLISM:
-Definition:
-multiple small deposits of fibrin, platelets, and cholesterol debris embolize from proximal atherosclerotic lesions or aneurysmal sites