ATHEROSCLEROTIC PERIPHERAL ARTERY DISEASE

Dr Jain T Kallarakkal MD, FRCP, DMInterventional Cardiologist

St Mary’s Hospital, Thodupuzha

Vascular diseases caused primarily by atherosclerosis and thromboembolic pathophysiologic processes of the aorta, its visceral arterial branches and the arteries of the lower extremity.

PAD

PAD is the term used to denote stenotic, occlusive and aneurysmal diseases of the aorta and its branches, exclusive of the coronaries.

PAD

Age < 50 years, with diabetes and one other risk factor (smoking, dyslipidemia, hypertension or hyperhomocysteinemia)

Age 50 to 69 with history of smoking and

diabetes

Age 70 or older

Who are at Risk?

Leg symptoms on exertion (suggestive of claudication) or ishemic rest pain

Abnormal lower extremity pulse examination

Known atherosclerotic coronary, carotid or renal artery disease

Who are at Risk?

40 – 59 Years : 3%

60 – 69 Years : 8%

> 70 Years : 19%

PREVALENCE

Exertionally associated calf pain

Pain relieved within 10 min of rest

Pain that does not come at rest

Intermittent Claudication

Leg or hip pain during walking (intermittent claudication) which stops when you rest.

Numbness, tingling or weakness in the legs.

Burning or aching pain in feet or toes when resting.

Symptoms

Sore on leg or foot that won’t heal

Cold legs or feet.

Color change in skin of legs or feet

Loss of hair on legs.

Stage I: Asymptomatic, incomplete blood vessel obstruction

Stage II: Mild claudication pain in limbIIA: Claudication at a distance of greater

than 200 metresIIB: Claudication distance of less than 200

metres Stage III: Rest pain, mostly in the feet Stage IV: Necrosis and/or gangrene of the limb

FONTAINE CLASSIFICATION

GRADE CATEGORY SYMPTOMS0 0 AsymptomatiCI 1 Mild claudication

2 Moderate claudication

3 Severe claudication II 4 Rest pain

5 Minor tissue loss; Ischemic ulceration not exceeding ulcer of the digits of the foot

III 6 Major tissue loss; Severe ischemic ulcers or frank gangrene

RUTHERFORD CLASSIFICATION

Auscultation of the abdomen and flank for bruits

Palpation of the abdomen and notation of the presence of the aortic pulsation and its maximal diameter.

Physical Examination

Palpation of pulses at the femoral, popliteal, dorsalis pedis, and posterior tibial sites.

Ausculation of both femoral arteries for the presence of bruits

Pulse intensity should be assessed and should be recorded numerically as follows:

0, absent

1, diminished

2, normal

3, bounding

The feet should be inspected, the color, temperature, and integrity of the skin and intertriginous areas evaluated, and presence of ulcerations recorded.

Additional findings suggesting severe PAD◦ distal hair loss◦ trophic skin changes◦ hypertrophic nails

Ankle Brachial Index (ABI)

Treadmill Test

Ultrasound

Computed tomography angiography (CTA)

Magnetic resonance angiography (MRA)

Digital subtraction angiography (DSA)

DIAGNOSTIC TOOLS

Ankle- brachial index

Quick and cost-effective

Normal ABI is >1.0

ABI <0.90 is used to define LEAD

Sensitivity and specificity are 79% and 96%

Ankle- brachial index

A 10–12 cm sphygmomanometer cuff placed just above the ankle and a handheld Doppler instrument (5–10 MHz) to measure the pressure of the posterior and anterior tibial arteries of each foot are required. ABI is the highest ankle systolic pressure divided by the highest brachial systolic pressure

Useful to assess lower extremity PAD anatomy, severity and progression

Can provide localizing information

Limited accuracy in tortuous, overlapping, or densely calcified arterial segments and insensitive for iliac arteries

Doppler

Differentiate claudication from pseudoclaudication

Useful to diagnose when resting ABI values are normal

Useful to measure the objective functional response to claudication therapeutic interventions

Treadmill Test

Useful to select patients who are candidates for endovascular or surgical revascularization

Associated soft tissue diagnostic information (e.g., aneurysms, popliteal entrapment and cystic adventitial disease)

Patients with contraindications to MRA (e.g., pacemakers or defibrillators)

Metal clips, stents, and metallic prostheses do not cause significant CTA artifacts

Computed tomography angiography (CTA)

Useful to select patients who are candidates for endovascular or surgical revascularization

Tends to overestimate the degree of stenosis May be inaccurate in arteries treated with metal

stents Cannot be used in patients with contraindications

to the magnetic resonance technique (e.g., pacemakers, defibrillators, intracranial metallic stents, clips, coils, and other devices)

Magnetic resonance angiography (MRA)

lifestyle modification

smoking cessation

daily exercise (30 min/day)

normal body mass index (≤25 kg/m2)

Treatment

Pharmacological treatment for blood pressure control lipid-lowering treatment to achieve LDL

cholesterol100 mg/dL with an option of 70 mg/dL if feasible.

In diabetic patients, glucose control should be obtained, with the target glycated haemoglobin (HbA1c) 7%

Phosphodiesterase inhibitor (PDE-3)

Promotes vasodilatation and inhibit platelet aggregation

More effective than pentoxifylline

Caution in patients with CHF

Cilostazol

Indicated in patients with lifestyle-limiting claudication and an inadequate response to conservative therapy

Obstructive distal aortic and iliac artery lesions are treated with endovascular techniques and an endovascular-first strategy can be recommended for all (TASC) A–C lesions

Low morbidity and mortality and a >90% technical success is seen

Endovascular therapy

Type A:1. Single stenosis <3 cm of the CIA or EIA (unilateral/bilateral)

Type B:2. Single stenosis 3 to 10 cm in length, not extending into the CFA

3. Total of 2 stenoses <5 cm long in the CIA and/or EIA and not extending into the CFA

4. Unilateral CIA occlusion

Trans Atlantic Inter Society Consensus (Ileac lesions)

Type C: 5. Bilateral 5 to 10 cm long stenosis of the CIA and/or EIA, not extending into the CFA

6. Unilateral EIA occlusion not extending into the CFA

7. Unilateral EIA stenosis extending into the CFA

8. Bilateral CIA occlusion

Type D: 9. Diffuse, multiple unilateral stenoses involving the CIA, EIA, and CFA (usually >10 cm long)

10. Unilateral occlusion involving both the CIA and EIA

11. Bilateral EIA occlusions12. Diffuse disease involving the aorta

and both iliac arteries13. Iliac stenoses in a patient with an

abdominal aortic aneurysm or other lesion requiring aortic or iliac surgery

Endovascular therapy is the preferred choice in patients with long and complex femoropopliteal lesions

Self expandable nitinol stents may be recommended as the first-line treatment

Femoropopliteal Disease

Type A: 1. Single stenosis <3 cm of the superficialfemoral artery or popliteal artery

Type B:2. Single stenosis 3 to 10 cm in length, not involving the distal popliteal artery

3. Heavily calcified stenoses up to 3 cm in length

4. Multiple lesions, each <3 cm (stenoses or occlusions)

5. Single or multiple lesions in the absence of continuous tibial runoff to improve inflow for distal surgical bypass

Trans Atlantic Inter Society Consensus (Femoropopliteal lesions)

Type C: 6. Single stenosis or occlusion longer than 5 cm

7. Multiple stenoses or occlusions, each 3 to 5 cm in length, with or without heavy calcification

Type D: 8. Complete common femoral artery or superficial femoral artery occlusions or complete popliteal and proximal trifurcation occlusions

Limb salvage is the primary indication for endovascular treatment of infrapopliteal lesions

Angioplasty of these arteries is usually not indicated in patients with intermittent claudication

Infrapopliteal disease

Diffuse aortoiliac disease is usually managed with aorto-biiliac or -bifemoral bypass

The surgical strategy depends on the lesion location and technical possibilities

Compared with the aortofemoral bypass, extra-anatomical bypasses present poorer patency rates and higher risk of complications.

Surgery

Therapeutic angiogenesis based on the use of angiogenic factors or stem cells to promote revascularization and remodelling of collaterals are being investigated, but too early to give recommendations

Future

Atherosclerosis is the most common cause (90%)

Typically ostial in location

FMD is the second common cause

Typically produce a beaded appearance

Renal Artery Disease

Hypertension before age 35 and after 55

Hypertension that abruptly becomes more difficult to control

Resistant hypertension

Patients with marked elevation in both systolic and diastolic pressures

Discrepancy in renal size > 1.5 cm

Patients who develop azotemia upon initiation of ACEI or ARB

Who all should be considered?

Duplex ultrasonography

◦Peak systolic velocity > 180 cm / sec 95% sensitivity and 90% specificity

◦Ratio of peak systolic velocity in stenosed renal artery to the peak systolic velocity in the aorta > 3.5, predicted 60% RAS with 92% sensitivity

Diagnostic tests

Metal may cause artifacts

Not a useful test for patients who have undergone renal artery stenting

Claustrophobia, Implanted metal devices

MRA

Gold standard

Catheter commonly used: Internal mammary, JR.

Pressure gradient PG > 20 mm hg or a MG > 0 mm hg is significant

Invasive angiography

Percutaneous revascularisation is reasonable for patients with hemodynamically significant RAS and accelerated hypertension, resistant hypertension, malignant hypertension, hypertension with an unexplained unilateral small kidney or hypertension with intolerance to medications.

Revascularisation

It is also reasonable for patients with RAS and progressive CKD with bilateral RAS or RAS of a solitary functioning kidney.

Reasonable for patients with significant RAS and flash pulmonary edema.

Reasonable for patients with significant RAS and ACS

Benefits are less well established when considering endovascular therapy for asymptomatic disease or for preservation of renal function

Surgical revascularisation is considered in those patients whose anatomy makes endovascular therapy less attractive and/or who require concomitant operative treatment of aortic disease.

Krum et al

Renal sympathetic denervation

Blood pressure reduction was significant

Large trials are required

Renal Artery Denervation

PAD is highly prevalent, particularly with advancing age

Despite the high prevalence it is still underdiagnosed and undertreated.

Diagnosis of PAD confers a 25-30% 5 year risk of cardiovascular death and additional 20% risk of non fatal major adverse cardiovascular events

Conclusions

Main focus of therapy for PAD is secondary prevention of stroke and MI, including:

◦ Smoking cessation

◦ Reduce LDL < 100

◦ HbA1c < 7%

◦ BP < 140/90 and < 130/80 with DM or RI

◦ Antiplatelet therapy

◦ Preventive foot care

Conclusions

For severe limb ischemia endovascular options may rival gold standard surgical approach

RAS is a common finding in patients with atherosclerosis

Atherosclerotic disease affects the ostium and proximal part of the renal artery, from direct extension of aortic disease

Conclusions

The diagnosis of RAS should be considered in patients with early or late onset hypertension or in patients with previously well controlled hypertension that was escaped

Invasive angiography remains gold standard for diagnosis

Conclusions

Revascularisation is reasonable for patients with significant RAS and recurrent HF, pulmonary edema and unstable angina.

The strategy is also reasonable for patients with uncontrolled hypertension and deteriorating renal function in the setting of significant RAS.

Conclusions

Thank You