Peripheral artery disease: Pathology review

8,799views

00:00 / 00:00

Questions

USMLE® Step 1 style questions USMLE

of complete

A 73-year-old man comes to the emergency department with sudden, severe leg pain. He was watching football at home when he experienced an acute-onset, sharp pain in the right calf that has progressively worsened. The patient reports being unable to feel the sock worn on that foot, and he is having difficulty moving his toes. He denies chest pain or shortness of breath. Medical history is significant for a small intracranial aneurysm that has been monitored on serial imaging and has remained stable in size for five years. The patient’s temperature is 37.0°C (98.6°F), pulse is irregularly irregular at 90/min, respirations are 20/min, and blood pressure is 135/85 mmHg. Physical exam shows pale and mottled skin starting 6 cm below the right tibial plateau and extending to the right toes. There is no swelling. Hair growth is normal. Carotid, radial, and femoral pulses are palpable bilaterally. The left posterior tibial artery pulse is palpable while his right is absent on palpation and has no signal on Doppler ultrasound. Which of the following locations is the most likely origin of this patient’s embolus?  

Memory Anchors and Partner Content

Transcript

Watch video only

Tariq is a 52-year-old individual who presents to the clinic complaining of left leg pain. He describes the pain as “cramping” and mostly located in his calf. He also mentions that the pain comes every time he walks from his home to the supermarket, and is relieved when he rests. Tariq also has a known history of hypertension, diabetes mellitus, and a myocardial infarction 2 years ago. On physical examination, there is a noticeable decrease in hair growth on the left side compared to the right, and the skin appears dry and shiny. There is no leg swelling, and there’s no back pain.

Peripheral artery disease is insufficient tissue perfusion due to narrowing or occlusion of the aorta or one of its peripheral branches supplying the limbs. Similar to coronary artery and cerebrovascular disease, the development of an atherosclerotic plaque that narrows or completely occludes an artery is the number one cause of peripheral artery disease, and so these diseases often coexist together.

So on the exam, an important clue may be an individual with a past medical history of a myocardial infarction or a stroke. In addition, look for risk factors of atherosclerosis, such as hypertension, diabetes mellitus, smoking and hyperlipidemia.

The symptoms of peripheral artery disease depend on how bad the occlusion is. In the early stages of the disease individuals may be completely asymptomatic. One of the first symptoms is intermittent claudication. This is characterized by cramping pain in the affected area that comes about during exercise, and is relieved with rest.

Individuals often describe a specific and often consistent distance that brings about the pain, such as walking 2 blocks. The location of the pain can also help give a clue about which artery is occluded. For example, hip claudication indicates aortic or iliac artery occlusion, whereas calf claudication points towards femoral or popliteal artery occlusion.

Sources

  1. "Pathophysiology of Heart Disease" Wolters Kluwer Health (2015)
  2. "Lifestyle and Dietary Risk Factors for Peripheral Artery Disease" Circulation Journal (2014)
  3. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  4. "Rapid Review Pathology" Elsevier (2018)
  5. "Medical treatment of peripheral arterial disease" JAMA (2006)
  6. "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary" Journal of the American College of Cardiology (2017)
  7. "Cilostazol for intermittent claudication" Cochrane Database Syst Rev (2014)