Case 1: Management of Progressive Peripheral Arterial Disease Despite Initial Medical Management
A 65-year-old man was sent from the clinic for worsening of left calf severe pain and decrease in exercise tolerance due to left calf pain. The patient had a 3-month history of intermittent left calf pain and denied trauma, back pain, fever, and leg weakness. Otherwise, the medical history was significant for hyperlipidemia. He was a former smoker and stopped smoking 6 months ago; however, he smoked 1 pack of cigarettes per day for the past 40 years before quitting. The patient denied use of alcohol or recreational drugs. His medications were low-dose aspirin and high-intensity atorvastatin. On physical examination, vital signs were normal. Body mass index was 28 kg/m2. Femoral pulses were diminished bilaterally. Popliteal, right dorsalis pedis, and right posterior tibialis pulses were faint. The left dorsalis pedis and posterior tibialis pulses were not palpable. Cardiac examination was normal. Otherwise, the physical examination was unremarkable. The ankle-brachial index was 0.67 on the left and 0.91 on the right. He was enrolled in a supervised exercise program 3 months ago, but the patient reported no improvement despite adherence to the exercise program, and his symptoms progressed. How would you manage this case?
This scenario represents a patient with progressive peripheral arterial disease (PAD) despite being on initial medical management. The signs of progressive PAD include progressive decrease in exercise tolerance due to worsening left leg pain and physical examination findings of nonpalpable dorsalis pedis and posterior tibialis pulse on the left side. The patient is already on initial medical management of PAD, including smoking cessation, aspirin, high-intensity statins, and a supervised exercise program.
PAD is most commonly characterized by narrowing of the aortic bifurcation and arteries of the lower extremities, including the iliac, femoral, popliteal, and tibial arteries. Atherosclerosis is the most common cause. Risk factors for PAD include smoking (current or past), diabetes mellitus, and increasing age. Patients with PAD are at increased risk for ischemic events, including myocardial infarction, stroke, and cardiovascular death. Patients with atherosclerotic risk factors (smoking, diabetes, hypertension, dyslipidemia, and advanced age) who have atypical limb symptoms (eg, leg weakness, paresthesia), exertional leg discomfort, and/or nonhealing ulcers should undergo initial testing with ankle-brachial index (ABI) measurement.
There is a wide spectrum of clinical manifestations because lower extremity PAD is defined by an abnormal ABI value rather than by symptoms. Patients may present with exertional leg pain relieved by rest (intermittent claudication), atypical exertional leg pain, rest pain, nonhealing wounds, ischemic ulcers, or gangrene.
ABI interpretation is as follows:
ABI 0.00 to 0.40: Severe PAD
ABI 0.41 to 0.90: Mild to moderate PAD
ABI 0.91 to 0.99: Borderline PAD
ABI 1.00 to 1.40: Normal
ABI >1.40: Noncompressible (calcified) vessel (uninterpretable result)
Initial medical management of PAD includes risk factor modifications, such as smoking cessation, high-intensity statins, diabetes control, and blood pressure control. In addition, patients should be started on antiplatelet therapy, such as aspirin, to decrease the risk of myocardial infarctions, stroke, and peripheral arterial events. Furthermore, patients should be encouraged to enroll in the supervised exercise program, which can improve symptoms. This patient is already on the initial medical management of PAD; thus, the most appropriate next step in management is to initiate cilostazol (a phosphodiesterase inhibitor with antiplatelet and vasodilator activity). The US Food and Drug Administration has placed a black box warning on the use of cilostazol in patients with heart failure. In patients with intermittent claudication and confirmed lower extremity PAD with an abnormal ABI (≤0.9), exercise training and medical therapy (cilostazol) have been shown to improve limb symptoms. If this patient does not have improvement in his symptoms with cilostazol or cannot tolerate cilostazol therapy, he should be referred for invasive management (endovascular or surgical revascularization).
Patients with symptomatic PAD may present with exertional leg pain relieved by rest (intermittent claudication), atypical exertional leg pain, rest pain, nonhealing wounds, ischemic ulcers, or gangrene.
Medical management, such as risk modification, antithrombotics, exercise training, and pharmacologic therapy (cilostazol), is recommended to improve limb symptoms in patients with PAD and intermittent claudication.
Case 2: Management of Pseudoclaudication
A 70-year-old woman presented to the emergency department with cramping pain in the buttocks and thighs with standing and walking. Symptoms were exacerbated after standing at work for several hours and were relieved by sitting. The patient reported she had been having these symptoms for the past 6 to 8 months and they were stable. However, recently she started noticing worsening of the symptoms. She denied trauma, focal deficit, and loss of sphincteric control. Her past medical history was significant for hypertension. She did not report a history of any major surgery. She smoked cigarettes for many years but stopped smoking 12 years ago. She denied alcohol use or intravenous or recreational drug use. Her home medications were amlodipine and lisinopril. On physical examination, vital signs were within normal limits. Body mass index was 22 kg/m2. Deep tendon reflexes were decreased at the ankles but normal at the knees. Lower extremity muscle strength was normal. No abdominal or femoral bruit was present. No skin changes were noted in the lower extremities. Distal pulses were palpable bilaterally. The resting ankle-brachial index was 1.1 on both sides. How would you proceed with this case?
This case scenario represents a patient with pseudoclaudication. This patient’s normal ankle-brachial index bilaterally, normal distal pulses, lack of a bruit, normal skin findings, and clinical history all suggest a diagnosis other than peripheral arterial disease.
Lumbar spinal stenosis can be described as an anatomic condition that involves narrowing of the central canal, lateral recess, and/or neural foramen.
Patients with pseudoclaudication (lumbar spinal stenosis) may report bilateral leg weakness associated with walking or with prolonged standing; symptoms are aggravated by prolonged standing and are relieved with bending at the waist. Nearly half of patients have absent deep tendon reflexes at the ankles, but reflexes at the knees and muscle strength are usually preserved.
The American College of Physicians recommends that advanced imaging with MRI or CT should be reserved for patients with a suspected serious underlying condition or neurologic deficits or who are candidates for invasive interventions. In the absence of these indications, back imaging is not indicated. An MRI of the lumbar spine can be done in this patient to confirm the diagnosis. Conservative treatment is suggested for the patients with no fixed or progressive neurologic deficits. Conservative management includes physical therapy and/or oral pain medication. Surgical therapy is suggested for patients who do not have an adequate clinical response to conservative therapy and who are functionally disabled by their symptoms and for patients who have a progressive neurologic deficit.
Lumbar spinal stenosis is narrowing of the central canal, lateral recess, and/or neural foramen.
Lumbar spinal stenosis may present as bilateral leg weakness associated with walking or with prolonged standing; symptoms are aggravated by prolonged standing and are relieved with bending at the waist.
MRI or CT should be reserved for patients with a suspected serious underlying condition or neurologic deficits or for patients who are candidates for invasive interventions
Conservative management includes physical therapy and/or oral pain medication. Surgical therapy is suggested for patients who do not have an adequate clinical response to conservative therapy and who are functionally disabled by their symptoms and for patients who have a progressive neurologic deficit.
Case 3: Management of Upper Extremity Peripheral Arterial Disease (Subclavian Steal Syndrome)
A 70-year-old man presented to the emergency department with a 3-month history of left arm fatigue and dizziness. The patient reported that 2 days ago, he became dizzy while standing on a stool and looking for a toolbox in an overhead shelf with the left arm. He noticed that his symptoms improved after 2 minutes of rest. In addition, he stated that left arm activity reproduced his arm fatigue and discomfort, which was mainly in the forearm. He had a significant medical history of hyperlipidemia and hypertension. He denied any surgery in the past. He had a 50-pack-year smoking history, but he denied use of alcohol or recreational drugs. Home medications included lisinopril, amlodipine, and atorvastatin. On physical examination, he was afebrile, blood pressure was 115/65 mm Hg in the left arm and 147/89 mm Hg in the right arm, and pulse rate was 75 bpm. On auscultation, a bruit was heard over the left supraclavicular fossa. Right carotid upstroke was normal. The left radial pulse and left carotid pulse were faint, and the left radial pulse was slightly diminished. Cardiac examination was normal. Physical examination was otherwise unremarkable. How would you manage this case?
This case scenario presents a patient with upper extremity peripheral arterial disease (PAD) and subclavian steal syndrome. The diagnosis was made based on the clinical presentation of left arm fatigue and dizziness with activity involving the left arm. The diagnosis was further supported by the physical examination findings such as significant difference in blood pressure between both arms, presence of bruit over the left supraclavicular fossa, and faint pulses over the left radial artery and left carotid artery. In addition, this patient had risk factors for PAD such as advanced age, smoking, hyperlipidemia, and hypertension.
Upper extremity PAD is characterized by atherosclerotic narrowing of the arteries in the upper extremities. Most patients with upper extremity PAD have no symptoms, although patients may present with symptoms. In patients at risk for atherosclerotic cardiovascular disease, measurement of bilateral arm pressures is indicated in asymptomatic and symptomatic patients to assess for upper extremity PAD. A characteristic finding on physical examination is a difference in systolic blood pressures between the arms, typically >15 mm Hg.
Symptomatic patients with upper extremity PAD present with arm claudication, arm ischemia, or dizziness with arm activity (subclavian steal syndrome).
The most appropriate next step in this patient suspected of having upper extremity PAD is CT angiography. Because this patient has arm claudication and a systolic blood pressure differential of 32 mm Hg between arms, imaging of the innominate and subclavian arteries with CT angiography is appropriate to confirm the diagnosis of upper extremity PAD and plan for intervention, such as revascularization. In addition, all patients should be managed with risk factor modifications, such as smoking cessation, high-intensity statins, and blood pressure control. Also, patients should be started on antiplatelet therapy, such as aspirin, to decrease the risk of myocardial infarctions, stroke, and peripheral arterial events. Furthermore, patients should be encouraged to enroll in the supervised exercise program, which can provide symptomatic relief. Patients should be started on cilostazol (a phosphodiesterase inhibitor with antiplatelet and vasodilator activity) for symptom relief. The decision for interventional therapy can be made based on the results of CT angiography.
Symptoms of upper extremity peripheral artery disease may include arm claudication, arm ischemia, or dizziness with arm activity.
CT angiography is useful to confirm the diagnosis and plan for intervention.
Smoking cessation is essential to reduce cardiovascular risk in patients with PAD. Antiplatelet monotherapy with aspirin is recommended for patients with PAD to reduce the risk for myocardial infarction, stroke, and peripheral arterial events. Supervised exercise training is the most effective treatment for improvement of functional status in patients with PAD. Cilostazol is recommended for patients with intermittent claudication.
Case 4: Management of Acute Limb Ischemia
A 60-year-old man presented to the emergency department due to acute left lower leg pain that began 3 days ago. The pain was severe at rest, and he reported that his left foot was cold compared to the right foot. He was not able to do any activity due to the pain and felt the left leg was weak. He denied any fever, trauma, or neurologic deficits. His medical history was significant for intermittent claudication for the past 4 years, hypertension, hyperlipidemia, and type 2 diabetes mellitus. His surgical history was significant for left femoral-popliteal bypass graft surgery for life-limiting claudication 1.5 years ago. He was a former smoker who had quit smoking 5 years prior, and he denied alcohol use or recreational drug use. His medications were low-dose aspirin, ramipril, hydrochlorothiazide, rosuvastatin, and metformin. On physical examination, vital signs were within normal limits. The left foot was cold and pale compared to the right foot, sensations were intact, and muscle strength was normal. The pedal pulses were not palpable in the left leg. Arterial Doppler ultrasound signals were not detectable over the left dorsalis pedis and left posterior tibial arteries. He was started on intravenous anticoagulation with heparin. How would you manage this case further?
This case scenario presents a patient with acute limb ischemia (ALI). The diagnosis of ALI was based on the history suggestive of acute pain in the left lower leg at rest; physical examination showing pallor, poikilothermia, and absence of pedal pulses in the left foot; and arterial Doppler ultrasound showing inability to detect signals over left dorsalis pedis and left posterior tibial artery. This patient has many risk factors for developing ALI, such as history of left femoral-popliteal bypass graft surgery for life-limiting claudication 1.5 years ago, former history of smoking, hypertension, hyperlipidemia, and diabetes mellitus type 2.
ALI is defined by a sudden or rapid decrease in limb perfusion, often manifested as a new pulse deficit, rest pain, pallor, and/or paralysis. ALI is a medical emergency and a life-threatening manifestation of PAD. ALI is most commonly caused by acute thrombosis of a lower extremity artery, stent, or bypass graft. Other causes include thromboembolism, vessel dissection (usually occurring periprocedurally), or trauma.
Classically, patients present with at least 1 of the “6 Ps”: paresthesia, pain, pallor, pulselessness, poikilothermia (coolness), and paralysis.