Case Study:

 Mr.  A.P.  is a 48 year male with hypertension and 25 year history of tobacco use.  Over the last 6 months, he has had progressive symptoms of right calf heaviness with exertion.  He has also noticed occasional numbness in his feet and some hair loss on his shin.  A trial of NSAIDs was unhelpful and nerve conduction tests were unremarkable.  Due to these symptoms and due to atypical chest pain, he was sent to cardiology for further evaluation.  Further questioning revealed that the patient was only able to walk 100 feet prior to onset of symptoms and his active lifestyle was being affected.

On physical exam, he was noted to have significant diminishment in the right popliteal pulse and distal right pedal pulses.  An ankle brachial index (ABI) was ordered.  The right ABI was 0.6 and the left ABI was 0.9.  Nuclear stress testing demonstrated a small area of inferior ischemia.  We proceeded with cardiac catheterization and lower extremity angiography.  Coronary angiography demonstrated 50% lesions in the LAD and RCA.  Lower extremity angiography demonstrated a severe right superficial femoral artery (SFA) lesion of 80% (Figure 1) and diffuse 50% stenosis in the left SFA.  We proceeded with successful atherectomy and balloon angioplasty of the right SFA and achieved an excellent result (Figure 2).  The patient was treated with aggressive antiplatelet therapy including aspirin and clopidogrel and begun on high dose statin therapy and fish oil.  At follow-up, the patient had noted complete resolution of his claudication symptoms. 

Discussion:

This case study demonstrates the modern management of lower extremity peripheral arterial disease (PAD) which is defined as obstructive atherosclerosis of the lower extremity limiting blood supply.  Classic symptoms of PAD include limb pain with exertion which improves with rest, defined as claudication.  A large majority of patients with PAD, however, are asymptomatic or have atypical symptoms thereby making diagnosis difficult.  Advanced PAD can lead to resting limb pain, tissue loss, infection, gangrene and eventually limb loss.  The prevalence of PAD is increasing.  In fact, over 27 million patients in the United States and Europe are affected by this condition.

The first step in management is the identification of risk factors which often include smoking, diabetes, dyslipidemia, and advanced age.  These risk factors need to be managed aggressively as patients with PAD are at significantly elevated risk of myocardial infarction and death from coronary heart disease which is the primary cause of mortality in this patient population.  In fact, as this case study demonstrates, coronary disease often co-exists with PAD.  For this reason, cardiologists should be actively involved in the care of peripheral vascular patients. 

Therefore, the American College of Cardiology and American Heart Association have recommended PAD screening questions for patients > 70 years old or > 50 with a history of smoking or diabetes.  At the Orlando Heart Center, we have instituted a screening questionnaire asking about symptoms of walking impairment, limb pain, or non-healing wounds.  A good physical examination should follow assessing for the presence of bruits and assessing for distal pulses at the femoral, popliteal, and pedal level.  Any concern regarding PAD should lead to the measurement of an ankle-brachial pressure index (ABI).  An ABI less than 0.9 is considered abnormal.  An exercise ABI may need to be obtained in patients with exertional symptoms but a normal resting ABI.  MRA and CTA are often useful tests for documentation of the location and extent of PAD with invasive angiography still being the gold standard.

Asymptomatic PAD can be managed medically with aggressive risk factor modification.  For patients with symptoms of mild claudication, a walking program and drug therapy with agents such as cilastozol can be considered.  Traditionally, revascularization had been limited to patients with advanced resting ischemia or severe claudication because open surgical revascularization was associated with significant morbidity.  However, the advent of endovascular treatment options has allowed treatment earlier in the disease process, thereby improving patients’ quality of life dramatically.  These procedures can often be done on an outpatient basis via a small puncture in the groin with same-day discharge.

Interventional cardiologists are particularly suited to care for patients for vascular disease.  A vascular medicine education curriculum is now an important part of many cardiology fellowship programs.  The use of medications for risk factor modification such as antiplatelet agents and lipid lowering therapy are second nature to cardiologists.  In addition, the catheter-based skills needed for coronary interventional procedures easily cross-over to peripheral vascular procedures.  Endovascular treatment options for patients with occlusive PAD included standard balloon angioplasty, cryoplasty, directional atherectomy, orbital atherectomy, and stent placement.  These options offer a much less invasive option for relief of symptoms compared to open surgery.  For very advanced and diffuse disease, surgical bypass still remains an option, but should only be considered if there is no viable endovascular option.

In summary, PAD remains an under-diagnosed condition associated with significant morbidity and mortality.  A high suspicion for its diagnosis and early referral to a cardiovascular specialist may improve quality of life and long-term outcomes.

Deepak P.  Vivek is an interventional cardiologist with the Orlando Heart Center.  He completed his interventional cardiology and peripheral interventional fellowships at the Cleveland Clinic Foundation