PERIPHERAL VASCULAR DISEASE: A VASCULAR SURGEON’S POINT OF VIEW

DANIEL S. RUSH, M.D.

NEW HORIZONS IN CARDIOVASCULAR HEALTH

JANUARY 27, 2012

INTRODUCTIONLOWER EXTREMITY PERIPHERAL

ARTERIAL DISEASE (PAD)

Affects 10 million people in the U.S.

About 4.3 % of everyone > 40 years old

About 14.5% of people > 70 years old

2 X increased incidence with each decade of life

100,000 patients undergo some form of revascularization each year

CLINICAL CONSIDERATIONS IN PAD

Underlying etiology of symptoms

Anatomy of arterial occlusion

Degree of limb ischemia

Co-morbid medical conditions

Functional status

Ambulation potential

Suitability for arterial intervention or reconstruction

Appropriate decision making

CLASSIFICATION OF LOWER EXTREMITY PAD

Intermittent Claudication

Critical Limb Ischemia (CLI)

Ischemia pain at rest

Ischemia ulceration

Gangrene

Infection

INTERMITTENT CLAUDICAITON

Most common symptom of PAD

Extertional leg pain

Life-style limiting to disabling

Generally one anatomic segment of arterial occlusion

Moderate limb ischemia

33% have treatable CAD

<1% per year risk of amputation

>3% - 5% per year risk of cardiac death

DIFFERENTIAL DIAGNOSIS OF LEG PAIN

Spinal stenosis

Nerve root compression

Peripheral neuropathy

Degenerative joint disease

Baker’s cyst

Venous claudication

Chronic compartment syndrome

Cardiac disease

CRITICAL LIMB ISCHEMIA

A systemic disease

Constant ischemic pain

Failure to heal wounds, ischemic ulcerations, and gangrene

Usually requires two or more segments of arterial occlusion

Severe limb ischemia

25% risk of amputation in one year

25% risk of cardiac death within one year

RISK FACTORS FOR PAD

Age

Sex

Race and Family history

Sedentary life-style

Smoking

Hyperlipidemia

Hypertension

Diabetes mellitus

Hypercaogulability

Hyperhomocysteinemia

Renal insufficiency

VASCULAR ASSESMENT IN PATIENTS WITH PAD

History and physical examination

Doppler examination

Vascular laboratory studies

CT ateriography

MR ateriography

Invasive contrast ateriography

VASCULAR LOBORATORY ASSESMENT OF PAD

Presence and direction of arterial blood flow

Character or quality of blood flow (Doppler waveforms)

Precise arterial systolic blood pressure measurement

Ankle / Brachial Index (ABI) – relative severity of arterial insufficiency

Qualitative anatomy of PAD (segmental arterial pressures)

Serial or comparative arterial assessments

Arterial Duplex (B-mode ultrasound and Doppler flow velocities)

CLINICAL USES OF VASCULAR LABORATORY ASSESSMENT

Evaluation of leg pain (PAD or something else?)

Severity of limb ischemia

Anatomic pattern of arterial occlusion

Objective limb function (exercise)

Post-operative follow-up

Wound healing or amputation level

INTERPRETATION OF ANKLE / BRACHIAL INDICIES (ABI’S)

Normal ABI 0.9 – 1.2

Mild limb ischemia ABI 0.7 – 0.9 Minimal symptoms

Moderate limb ischemia ABI 0.4 – 0.7 Claudication

Severe limb ischemia ABI < 0.4 Rest pain, Tissue loss

Non-compressible ABI > 1.2

MEDICAL MANAGEMENT OF PAD

Establish a diagnosis of PAD

Smoking cessation (disease progression)

Risk factor modification:

Hypertension (stroke risk reduction – ACE inhibitors)

Hyperlipidemia (disease progression, inflammatory response – “statins”)

Diabetes mellitus (wound healing and infection – glycemic control)

Coronary artery disease (MI risk reduction – Beta blockers)

Supervise exercise and conditioning (improve exercise tolerance and strength)

Treated associated causes of leg pain (neuropathy and arthritis)

CHARACTERISTICS OF INTERMETTEMNT CLAUDICATION

Exercise induced pain symptoms

Absent femoral and/or pedal pulses

ABI’s 0.4 - 0.7 range indicating moderate limb ischemia

One level of arterial occlusion

Aorto-iliac (LeRiche Syndrome) – hip or calf pain, vasogenic impotence

SFA occlusion – calf pain

Medical treatment preferred

Often successfully treated with endovascular techniques

Surgery reserved for sever symptoms in good risk patients

CHARACTERISTICS OF CRITICAL LIMB ISCHEMIA

Ischemia pain at rest or tissue loss

Absent femoral and/or pedal pulses

Distal rubor, ulceration, gangrene, and/or infection (risk of amputation)

ABI’S < 0.4 indication severe limb ischemia

Two levels of arterial occlusion (unless diabetic)

Medical treatment alone is usually ineffective

Sometimes improved with endovascular techniques

Surgical bypass is usually required

SURGICAL AND INTERVENTIONAL TREATMENT OPTIONS

Arterial reconstructions

Endarterectomy

Patch angioplasty

Bypass (autologous vein graft, prosthetic graft)

Endovascular techniques

Thrombectomy

Atherectomy

Balloon angioplasty

Stent placement

Endograft (covered stent)

TREATMENT OF AORTO-ILIAC OCCLUSIVE DISEASE

Aorto-Femoral Bypass (AFB) 3-5% M&M 90% 5 year patency

Aortic endarterectomy 3-5% M&M 80% 5 year patency

Extra-anatomic Bypass 1-2% M&M 60% 5 year patency

Iliac balloon angioplasty < 1% M&M

Claudication Stenosis 65% 5 year patency

Occlusion 54% 5 year patency

Critical ischemia Stenosis 53% 5 year patency

Occlusion 45% 5 year patency

Iliac stent <1% M&M

Claudication Stenosis 77% 5 year patency

Occlusion 61% 5 year patency

Critical ischemia Stenosis 57% 5 year patency

Occlusion 51% 5 year patency

TREATMENT OF INFRA-INGUAL OCCLUSIVE DISEASE

Ak Fem-pop bypass 1-2% M&M

GSV graft 69% 5 year patency

PTFE graft 60% 5 year patency

BK Fem-pop bypass 1-2% M&M

GSV graft 77% 5 year patency

PTFE 40% 5 year patency

SFA-pop balloon angioplasty < 1% M&M

Claudication Stenosis 53% 5 year patency

Occlusion 36% 5 year patency

Critical ischemia Stenosis 31% 5 year patency

Occlusion 16% 5 year patency

MORBIDITY AFTER LOWER EXTREMITY BYPASS

Healing and recovery time 15-20 weeks

Wound complications 15-25%

Lymphedema 10-20%

Graft stenosis 20%

Graft thrombosis 10-20%

Graft infection 1-3%

Major amputation 5-10%

PROBABILITY OF BYPASS FAILURE BY CO-MORBIDITY

Impaired ambulation 58% 6.4 Odds ratio

Distal PAD 46% 3.9 Odds ratio

ESRD 35% 2.5 Odds ratio

Gangrene 34% 2.4 Odds ratio

Hyperlipidemia 11% 0.6 Odds ratio

FACTORS INFLUENCING SURGICAL TREATMENT RESULTS OF PAD

Age

Atherogenic risk factors

Co-morbidities

Clinical indication for treatment

Severity of ischemia

Segmental anatomy of arterial occlusive disease

Choice of treatment (open or endovascular)

Technical difficulty

Choice of materials

Primary or secondary procedure

CONCLUSION

The diagnosis and treatment of PAD is not just a vascular surgical problem.

Risk factor modification (Vascular Medicine) will become an increasingly important adjunct to all surgical and endovascular therapies.

Primary care providers will have a greater role in the treatment of PAD.

Traditional measures of procedural treatment success such as morbidity and vessel patency are no longer a sufficient means of evaluating success.

New endovascular technologies have greatly broadened the number of treatment options available and will continue to evolve in the near future.