C 2007, the Authors C 2007, Blackwell Publishing, Inc. Journal compilation DOI: 10.1111/j.1540-8183.2007.00264.x
Contemporary Percutaneous Treatment of Infrapopliteal Arterial Disease: A Practical Approach JAAFER A. GOLZAR, M.D., AKHILA BELUR, M.D., LUTHER I. CARTER, M.D., NISHIT CHOKSI, M.D., ROBERT D. SAFIAN, M.D., and WILLIAM W. O’NEILL, M.D. From the Division of Cardiology, William Beaumont Hospital, Royal Oak, Michigan
(J Interven Cardiol 2007;20:222–230)
Introduction Percutaneous treatment of peripheral arterial disease (PAD) has gained tremendous interest over the last few years. New devices and increasing operator experience has made percutaneous therapy first line therapy at many institutions. Infrapopliteal interventions are extremely rewarding because establishing straight line blood flow to the foot can provide adequate perfusion to heal ischemic ulcers and prevent amputation. With appropriate patient selection, acute procedural success and long-term outcomes may be better than surgical bypass making percutaneous revascularization an important first treatment option at most institutions.
and is noted to be 2 to 3 times more in smokers than nonsmokers.3,4,6–11 Smoking is also 2 to 3 times more likely to cause lower extremity PAD than CAD.11 Diabetes mellitus is present in 12–20% of the patients with lower extremity PAD.5,12 It increases the risk for PAD by 2- to 4-fold and is proportional to the severity and duration of diabetes.5,12,13 The risk of PAD increases with elevated levels of total cholesterol, elevated LDL and decreased levels of HDL.14,15,16 Hypertriglyceridemia and lipoprotein(a) are independently associated with PAD.17 Hypertension is associated with an increased risk of lower extremity PAD. The Framingham Heart Study documented a 2.5 and 4-fold increase in intermittent claudication in men and women, respectively, with hypertension.11
Epidemiology The prevalence of PAD is estimated to be 27 million people in North America and Europe.1 The major risk factors for PAD are similar to those associated with atherosclerotic coronary artery disease (CAD), which include: advanced age, male sex, cigarette smoking, diabetes mellitus, hypertension and dyslipidemia.2 Cigarette smoking is a significant modifiable risk factor for CAD and PAD. More than 80% of the patients with PAD are either current or former smokers.3,4,5 The risk is correlated to the number of cigarettes smoked Address for reprints: Dr. Jaafer Golzar, M.D., Heart Care Centers of Illinois, Hickory Creek Office Center, 19001 Old La Grange Road, Mokena, Illinois 60448, e-mail:
[email protected]
222
Diagnosis PAD has a wide range of presentation from being asymptomatic to claudication to critical limb ischemia. Critical limb ischemia (CLI) is manifested by ischemic rest pain, ulcers, or gangrene attributable to arterial occlusive disease. Lower extremity pain resulting from nonvascular etiologies must be differentiated from intermittent claudication. An accurate history is important in the diagnosis of PAD. Once a diagnosis of atherosclerotic vascular disease is determined to be the cause of the patient’s symptoms, the Fontaine or Rutherford classification is useful to classify the severity of ischemia (Tables 1 and 2).
Journal of Interventional Cardiology
Vol. 20, No. 3, 2007
PERCUTANEOUS TREATMENT OF INFRAPOPLITEAL ARTERIAL DISEASE Table 1. Fontaine Classification Stage
Clinical Presentation
I II a II b III IV
Asymptomatic Mild claudication Moderate to severe claudication Ischemic rest pain Ulceration or gangrene
Adapted from reference18
An objective way of screening for PAD is by measuring the Doppler ankle-brachial index (ABI). An abnormal ABI indicating PAD is defined as less than 0.90. The sensitivity of the ABI is 90%, and the specificity is 98% for an angiographically defined stenosis of 50% or more in a major artery.19–21 However, ABI measurements in diabetic patients may not be reliable, as the arteries are calcified.22 Noninvasive tests like duplex ultrasound are useful in documenting the patency of a single arterial segment. However, the assessment of the entire lower extremity arterial tree by the duplex ultrasound is imprecise.23 Lower-extremity computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) are increasingly being used in patients with PAD. MRA and CTA are more specific and sensitive when compared to duplex ultrasonography and approaches the accuracy of contrast arteriography.24 However, contrast arteriography remains the gold standard in assessing PAD.
Medical Treatment Noninvasive treatments for improving symptoms of claudication include lifestyle modification such as smoking cessation and regular exercise.25,26 Adequate blood pressure control, particularly with the use of
angiotensin-converting enzyme inhibitors, has shown to improve claudication.27,28,29 Statin therapy should be used in patients with PAD. The American College of Cardiology (ACC) and American Heart Association (AHA) recommend the use of statin therapy in all patients with PAD and an LDL of greater than 100 mg/dL or an LDL of less than 100 mg/dL and a very high-risk profile. Very high-risk features include: multiple major risk factors, diabetes or the metabolic syndrome. The recommended LDL cholesterol goal is less than 100 mg/dL, but when risk is very high, the goal is less than 70 mg/dL.30 Cilostazol is a phosphodiesterase 3 inhibitor, increasing levels of cyclic adenosine monophosphate. Although the mechanism of action in patients with claudication is not known, it has been shown to have vasodilator and anti-platelet properties.31,32 Five prospective, randomized trials have shown that cilostazol improves walking distance by 40–60% in patients with intermittent claudication after 12–24 weeks of therapy.33–37 Tables 3 and 4 summarize the ACC/AHA Class I recommendations for medical therapy in patients with PAD and recommendations from the American Diabetes Association for management of patients with diabetes and PAD, respectively.30,38,39
Patient Selection The technical and clinical success of percutaneous treatment is based on appropriate patient selection. Limb salvage for patients with critical limb ischemia (CLI), defined in the Rutherford-Becker classification as categories 4, 5, 6 and Fontaine classification 3 and Table 3. ACC/AHA Class I Recommendations for Medical Therapy in Patients with Peripheral Arterial Disease. Medical Therapy Antihypertensive therapy
Table 2. Rutherford-Becker Classification Grade 0 I I I II III III
Category
Clinical Presentation
0 1 2 3 4 5 6
Asymptomatic Mild claudication Moderate claudication Severe claudication Ischemic rest pain Minor tissue loss Ulceration or gangrene
Adapted from reference.18
Vol. 20, No. 3, 2007
Aspirin therapy Clopidogrel HMG coenzyme-A reductase inhibitor (statin)
Goal of Therapy Blood pressure less than 140/80 (nondiabetic) Blood pressure less than 130/80 (diabetics or chronic renal disease 75 mg–325 mg daily 75 mg daily as an alternative to aspirin Goal LDL less than 100
ACC = American College of Cardiology; AHA = American Heart Association. Adapted from reference.30
Journal of Interventional Cardiology
223
GOLZAR, ET AL. Table 4. Target Levels of Risk Factors in Patients with Diabetes
