A marker for myocardial infarction and ischemic stroke

Methas Arunnart MD.

PAD – a marker for MI and IS

Cerebrovascular disease(ischaemic stroke, transient ischaemic attack)

Coronary artery disease(stable/unstable angina, myocardial infarction)

PAD (intermittent claudication, critical leg ischaemia, amputation, gangrene, necrosis)

• Atherothrombosis = thrombus formation on top of existing atherosclerosis

• Occurs in multiple arterial beds

Murabito JM et al. Circulation 1997;96:44–49; Laurila A et al. Arterioscler Throm Vasc Biol 1997;17:2910–2913;Malinow MR et al. Circulation 1989;79:1180–1188; Brigden ML. Postgrad Med 1997;101:249–262.

Gender (male) Age Smoking Hypertension Diabetes Hyperlipidaemia Hypercoagulable Hyperchromocysteine CKD

PAD

Ischaemicstroke

Myocardialinfarction

Atherosclerosis Atherothrombosis

• Incidence and prevalence of intermittent claudication* increase with age

• Prevalence in men aged 45–50 years is 1% • Prevalence is 3–3.5% in men aged > 50 years• Similar trend in women, increase with age

• More common in men than in women• Twice as many men as women aged > 50 years have

intermittent claudication (3.5% and 2%, respectively)

• Predominance in males disappears after age of 70

Weitz JI et al. Circulation 1996;94:3026–3049. * Rose questionnaire criteria Bull. Wld Hlth Org. 1962;27:645-658

Per

cen

tag

e o

f g

rou

p

Concurrentcardiovascular disease(MI, CABG, stroke orstroke surgery)

PADNo

0

10

20

30

40

50

Men Women

Yes YesNo

Criqui MH et al. Vasc Med 1997;2:221–226.

Stage Clinical

I Asymptomatic

IIa Mild claudication

IIb Moderate to severe claudication

III Ischemic rest pain

IV Ulceration or gangrene

Critical limb ischemia

Fontaine classification

• Detection of asymptomatic PAD has value because it identifies patients at increased risk of atherosclerosis at other sites.

• Patients with asymptomatic PAD, most often detected by ABI, should be treated to reduce their risk

• The normal ABI is 0.9-1.3 If symptoms strongly suggest claudication, exercise testing should be performed.

• ABI >1.3 suggests the presence of calcified vessels and need for additional vascular studies

• ABI ≤0.9 is diagnostic of PAD, has Sens.95% Spec.100%, • ABI 0.4 - 0.9 often associated with claudication.

• ABI < 0.4 represents multilevel disease and may be associated with Critical limb ischemia

normal toe-brachial index is 0.7 to 0.8

• Intermittent claudication

• Exercise-induced ischemic calf-muscle pain relieved by rest

• Increased mortality rate from stroke and MI 2-3 times

• Atypical symptoms•Pain similar to classic claudication, but does not cause the patient to stop walking•Pain similar to classic claudication, but does not involve calves or not resolve within 10 min. of rest•Leg pain on both exertion and rest

• Buttock and hip – aortoiliac disease*Leriche syndrome triad - claudication,

absent femoral pulses and erectile dysfunction.

• Thigh – aortoiliac or common femoral artery• Upper two-thirds of the calf – superficial femoral

artery• Lower one-third of the calf – popliteal artery• Foot claudication – tibial or peroneal artery

• Ischemic rest pain -  severe pain which is not readily controlled by analgesics

• Ischemic ulcer - typically form at sites of increased focal pressure such as the lateral malleolus, tips of toes, metatarsal heads, and bunion area. They are usually dry and punctate.

• Gangrene - can be described as either dry or wet.

Neuropathic ulcer

Venous ulcer

• vascular- aneurysm, limb trauma, radiation exposure, vasculitis, or ergot use for migraines. Popliteal entrapment syndrome, Chronic venous disease

• Neurological pain - neurospinal (eg, disc disease, spinal stenosis, tumor) or neuropathic causes (eg, DM, alcohol abuse)

• Musculoskeletal - pain derives from the bones, joints, ligaments, tendons, and fascial elements of the lower extremity.

• Lifestyle modification• Smoking cessation• Regular exercise training• Diet control

• Pharmacological treatment• platelet aggregation suppressor

• Antiplatelet therapy• Control risk factors (e.g. DM,HT,DLP)

• Surgery – Pt. with severe claudication(same as chronic limb ischemia)

• Segmental Doppler pressures• volume plethysmography• Duplex imaging• CT Angiography• Magnetic resonance angiography• Contrast angiography

• Segmental Doppler measurements involve placement of cuffs at the levels of the proximal and distal thigh, calf, and ankle.• At the thigh - aortoiliac or superficial femoral artery disease• At the calf - distal superficial femoral artery, popliteal disease• At the ankle - infrapopliteal disease.

• In addition, a toe pressure of less than 60% of the ankle pressure indicates digital artery occlusive disease

• This technique is performed by injecting a standard volume of air into pneumatic cuffs placed at various levels along the extremity. Volume changes in the limb segment below the cuff are translated into pulsatile pressure.

•

•  in experienced hands, provide accurate localization and quantification of lesions; it can also help differentiate stenosis from occlusions, an advantage over segmental Doppler pressures or plethysmography.

• However, a great deal of time and expertise are required,this modality is not the first choice for screening.

• useful tool in following known lesions for evidence of progression and for monitoring vascular reconstructions

•  The development of multidetector computed tomographic (MDCT) scanners now allows rapid acquisition of high resolution, intravenous contrast enhanced images from patients with suspected PAD and is increasingly being used in the evaluation of critical limb ischemia

• Becoming increasingly popular, particularly in patients who have a contraindication to standard contrast angiography.

• Requires careful evaluation and significant experience with MRA, and cooperation between the radiologist and vascular surgeon.

• remains the gold standard

• It should be performed in patients without a contraindication who are expected to undergo revascularization.

• A complete study of the aorta, iliac, femoral, popliteal, and run-off vessels is usually done on both sides since atherosclerotic disease is usually bilateral and occurs at multiple levels

Acute vs chronic

• Definition:sudden decrease in limb perfusion that causes a potential threat to limb viability in patients who present within 2weeks of the acute event.

manifested by ischemic rest painischemic ulcersgangrene

Thrombosis

Vascular grafts

Atherosclerosis

Thrombosis of aneurysm

Entrapment syndrome

Hypercoagulable state

Low flow state

EmbolusCardiac source Atrial fibrillation Myocardial infarction Endocarditis Valvular disease Atrial myxoma Prosthetic valvesArterial source Aneurysm Atherosclerotic plaque

TraumaBlunt

Penetrating

Iatrogenic

• Diagnosis : The “6P's" of acute ischemia •pain•pulselessness•pallor•paresthesia•Paralysis•Poikilothermic

ViableMarginally-threatened

Immediately-

threatenedNonviable

Pain Mild Severe Severe Variable

Capillary refill

Intact Delayed Delayed Absent

Motor deficit None None Partial Complete

Sensory deficit

None Minimal Partial Complete

Arterial Doppler

Audible Inaudible Inaudible Inaudible

Venous Doppler

Audible Audible Audible Inaudible

Treatment Urgent work-up

Emergency surgery

Emergency surgery

Amputation

• — Angiography is the diagnostic procedure that provides the most useful information; demonstrating detailed arterial anatomy, distinguish between thrombosis and embolism.

• it is not possible to perform this test in every case. Patient with threatened extremity should have immediate surgical revascularization with intraoperative angioography

• Heparin - Once the diagnosis of acute arterial occlusion has been made the patient should immediately receive an intravenous heparin bolus followed by a continuous heparin infusion

• Refer to speccialist

• should undergo urgent arteriography to plan surgical or percutaneous revascularization.

• Thrombolytic therapy VS surgical revascularization thrombolytic therapy is a safe and effective alternative to surgery in appropriately selected patients. Although many patients treated with thrombolytic therapy will subsequently require surgical or percutaneous revascularization

• Clinical features are useful to help determine (embolus versus thrombus)• The location and length of the lesion• The duration of symptoms• The availability of autologous vein for bypass grafting• The suitability of the patient for surgery

• As an example, a proximal embolus at the bifurcation of the common femoral artery is an ideal lesion for embolectomy. On the other hand, embolus to a distal vessel (eg, to the tibial artery) may be best treated with a thrombolytic agent. The major use of PTA is in the treatment of an underlying lesion after the clot has been lysed with thrombolytic therapy.

• Should undergo emergent surgical revascularization. • irreversible changes can occur within 4-6 hours of ischemia.

• Embolectomy is often all that is required to relieve the occlusion and provide adequate blood flow to the extremity.

• intraoperative completion arteriogram after the embolectomy to evaluate the adequacy of distal blood flow.

• Intraoperative thrombolytic therapy may also be used if there are small emboli in the distal runoff vessels.

• Fasciotomy may be required to prevent the development of a compartment syndrome

• should undergo prompt amputation.• Arteriography is usually not necessary.

• Delays in amputation of a nonviable extremity can result in infection, myoglobinuria, acute renal failure, and hyperkalemia.

• Definition: decrease in limb perfusion that causes a potential threat to limb viability in patients who present > 2weeks

• most often seen when two or more levels of the arterial tree

• The ACC/AHA practice guidelines suggested the following distribution of outcomes at one year in these patients:• Alive with two limbs – 50%• Amputation – 25%• Cardiovascular mortality – 25%

• Risk factor reduction• Wound care – conservative management

• Prostaglandin E1?? -  there was no long-term clinical benefit and at six months

• Imaging – duplex imaging,CTA,MRA,contrast angiographyt

• Revascularization: Angioplasty VS Bypass surgery Catheter-based intraarterial thrombolytic therapy

ACC/AHA guidelines for PAD recommend the following:

•For patients with an estimated life expectancy < 2 years or those who do not have autogenous vein available as a conduit, balloon angioplasty is reasonable as the initial procedure

•For patients with an estimated life expectancy of ≥ 2 years, and who have available autogenous vein conduit, a bypass surgery is reasonable to perform as the initial treatment

•  — Catheter-based intraarterial thrombolytic therapy is an alternative to surgery or percutaneous intervention in the management of acute thrombosis superimposed on chronic stenosis or occlusion in patients with critical limb ischemia