By: Alan Micklin,
M.D., F.A.C.C.

June 2004 – NLHBJ in alliance with health professional societies form PAD Coalition commit to raise awareness and promote education for PAD.
October 2005 – ACC/AHA Joint Task Force issues Practice guidelines for the evaluation and the treatment of PAD
Aug 2007 – US Senate passes resolution designating September as National Peripheral Arterial Disease Month.

Why is PAD receiving all of this attention?
Consider the following statistics:
•  It is estimated that over 12 million Americans have PAD.
•  Up to 20% of people less than 85 years of age and 20-30% of people over 70 years of age have PAD.
•  2/3 of all patients with PAD are completely asymptomatic or has atypical symptoms not suggestive of claudication.
•  3/4 of all patients with PAD are unaware of its presence.

Consider the prognosis if left unrecognized:
•  PAD patients have 2x the annual risk of MI or CAD patients compared to normal population.
•  PAD patient has 4x the annual risk for cardiovascular death.
•  PAD patient with severe LE ischemia have a 25% annual mortality rate.
•  60-80% of patients with PAD have significant CAD of at least one vessel.
•  12-25% of patients with PAD have hemodynamically significant carotid artery stenosis.

Given the prevalence and prognosis of PAD, it is imperative for physicians to improve identification of the patients with PAD and institute appropriate risk factor modification and symptomatic treatment.

Major risk factors for PAD include smoking, diabetes, dyslipidemia, hypertension or other coexisting atherosclerotic disease (coronary, carotid, and aortorenal). Smoking increases risks of PAD up to sixfold and increases claudication up to tenfold. PAD may be seen in both active and previous smokers and increases in a dose-dependant manner with the number of cigarettes smoked per year and number of years. Diabetes mellitus increases PAD up to 4x compared to the non diabetic population.  Diabetics with PAD are over 10 times more likely to undergo amputation compared to the non diabetic. The presence of dyslipidemia is associated with an 11% increased risk of PAD.  Hypertension also increases risk but to a lesser extent. Carotid disease, abdominal aortic aneurysm, or other atherosclerotic disease should alert the clinicians to the strong likelihood of coexisting PAD.

The diagnosis of PAD during the physical exam can be difficult. Several studies have confirmed low sensitivity in the diagnosis of PAD from physical examination alone.  ABI testing can be very helpful in identifying patients with PAD when history and physical exam are not diagnostic. The following groups have been identified as high risk groups by the ACC/AHA Task Force:
•  Age less than 50 with Diabetes Mellitus and one additional risk factor
•  Age 50 – 69 with history of Diabetes Mellitus or smoking
•  Age 70 or older (all)
•  Abnormal pulse examination
•  Known coronary, carotid and renovascular disease ABI testing can be helpful in identifying the presence, severity and general location of PAD. ABI grading scales may vary somewhat but generally are categorized in the following manner:
ABI 0.9 – 1.1  normal (ABI approaching 0.9 borderline)
ABI 0.7 – 0.89  mild PAD
ABI 0.4-0.69 moderate PAD
ABI <0.4  severe PAD, rest pain
ABI >1.30     non-compressible vessels

Patients with non-compressible vessels (increased frequency in diabetes) require alternative methods for PAD diagnosis such as TBI (toe brachial index) or an imaging study.  If a strong clinical suspicion for PAD exists and resting ABI is normal, then exercise ABI should be considered.  In the patient with symptomatic claudication, ABI may be used to grade severity of disease. However, if revascularization is deemed necessary based on severity of symptoms, alternative imaging with arterial duplex, CTA, MRA or angiography should be undertaken.

The identification of asymptomatic PAD should prompt treatment to help prevent its progression and decrease atherosclerotic events. Lipid lowering therapy should be instituted for goal LDL of no greater than 100 and <70 in high risk individuals. Blood pressure lowering to <140/90 in the non diabetic and 130/80 in the diabetic should occur.  In the diabetic population HgbA1c < 7% can help to reduce microvascular complications and potentially improve cardiovascular outcomes. Smoking cessation should be advised and smoking cessation interventions, including behavior modification, nicotine replacement therapy or medication therapy with buproprion should be offered.

Antiplatelet therapy has been shown to reduce risks of MI, stroke or vascular death in individuals with PAD. Asprin administration at dose ranges of 75 – 325 mg is appropriate.   Plavix may be used as an alternative to ASA and may be more effective than asprin in preventing events in individuals with symptomatic PAD.  Coumadin has not been shown to be of benefit in these patients.

Symptomatic PAD (claudication) should include the treatment discussed for asymptomatic disease in combination with the following measures. Supervised exercise training should be performed for a minimum of 30-45 minutes, three times weekly for at least 12 weeks. Cilolstazol (100 mg po bid) is indicated to help improve symptoms and increase walking distance. Pentoxifylline (Trental) effectiveness is not well established and should only be considered if an alternate to Cilostazol is needed.  Revascularization, either percutaneously or surgically, is recommended for lifestyle limiting claudicating, resting pain or non-healing ulcers.   The decision regarding percutaneous versus surgical repair is based largely on anatomy and the patient’s clinical features.

In summary, PAD is a prevalent yet vastly underdiagnosed condition. Its prognosis is less favorable than most cancers or other forms of atherosclerotic disease. Our society, including our governing bodies and payors, are recognizing the societal economic impact of this condition.  Our medical societies including the AMA, ACC, AHA, ADA, AAFP have all recently addressed this topic. As physicians, we have the responsibility and the tools to modify the course of the disease and its associated complications, as well as improve the functional capacity and prognosis of our patients.

Dr. Alan Micklin joined Cardiology Physicians, P.A. in July of 2006. He began his studies as an undergraduate biology major at the University of Delaware and graduated in 1986. He then went on to attend the Hahnemann University School of Medicine from 1986 to 1990. Upon his graduation in 1990, he started his residency in Internal Medicine at Hahnemann University. He began his fellowship in cardiovascular disease at Hahnemann in 1993 and was the chief cardiology fellow from 1994-1995. Dr. Micklin is
certified in internal medicine and cardiovascular disease, as well as interventional cardiology. He has also been certified to perform nuclear cardiology procedures since 1996 and is certified to interpret vascular ultrasound studies.

Dr. Micklin specializes in both nuclear and interventional cardiology and had been practicing since 1996 in Charlotte, North Carolina before joining Cardiology Physicians. At the University of Delaware he was a member of the Phi Beta Kappa and at Hahnemann University he was a member of Alpha Omega Alpha Honor Societies. He also received a commendation for Superior Performance during his residency at Hahnemann. Some of his clinical responsibilities include nuclear stress testing, echocardiography, and vascular ultrasound. As an interventional cardiologist, Dr. Micklin also performs diagnostic cardiac catheterization, including intravascular ultrasound, as well as stent placement and angioplasty. He has a strong commitment to inpatient and outpatient clinical patient care.

Dr. Mickin is married with three children. Both he and his wife attended the University of Delaware and were members of the Class of 1986. Hobbies include boating, skiing and golf.

September is National Peripheral Arterial Disease (PAD) Awareness Month

PAD is often asymptomatic but easily detectable with simple noninvasive testing. If you are in one of the following groups you are at increased risks.

1 – Age > 70 years
2 – Age > 50 years with one of the following

A – Diabetes
B – Elevated cholesterol
C – High blood pressure
D – Family history of stroke or heart attack
E – Personal history of Coronary Artery Disease or stroke
F – Smoker

3 – Age < 50 years if smoker or diabetic and one of the risk factors listed above.

If you would like more information on peripheral arterial disease, please contact the office at 302-366-8600 for a free brochure.

Cardiology Physicians, P.A.
www.cardiocppa.com

Abby Medical Center
One Centurian Drive
Suite 200
Newark, DE 19713
302.366.8600

1401 Foulk Road
Suite 201
Wilmington, DE 19803
302.478.5055