The Basics of Critical Limb Ischemia (CLI)

Critical limb ischemia (CLI) is the most severe stage of peripheral artery disease (PAD), a progressive condition caused by significant arterial blockages. These blockages develop when arteries narrow and harden due to excessive plaque buildup, limiting the flow of oxygen-rich blood to the limbs.

Reduced blood flow can cause intense pain in the legs and feet, even while resting at night. In severe cases, circulation may be so restricted
that parts of the limb are at risk of developing gangrene.

Common Signs of CLI

  • Limited mobility due to pain or weakness in the legs
  • Non-healing wounds or ulcers, which may progress to gangrene or tissue loss
  • Persistent pain in the legs or feet, often worsening at night or even while at rest
  • Weak or absent pulses in the legs and feet
  • Temperature changes, such as consistently cold feet or lower legs
  • Skin changes, including shiny, dry skin or slow-healing sores
  • Changes in toenails, such as thickening or brittleness

CLI Diagnostic Procedures and Treatments

Getting prompt help for CLI is crucial. If left untreated, the disease can progress and lead to serious complications that affect quality of life.
Screening is important—and it can be simple. Your doctor will review your medical and family history, perform blood tests, and conduct a physical exam. They may also use a combination of diagnostic tools to confirm a diagnosis. These tools may include:

  • Ankle-brachial index
  • Duplex ultrasound
  • CTA angiography
  • Transcutaneous pulse oximetry
  • MRA angiography
  • Intravascular ultrasound

If your doctor diagnoses you with CLI, several treatments may be recommended to restore blood flow to the foot:

  • Atherectomy
  • Angioplasty with stent placement
  • Bypass grafting
CLI-Image

Risk Factors for CLI

CLI affects more than 2 million Americans — about 12% of adult population. Alarmingly, over 40% of those diagnosed may require a major amputation within six months. Several factors increase the risk of developing CLI:

Medical Conditions
High cholesterol, high blood pressure, and diabetes can raise the likelihood of arterial disease.

Smoking
Tobacco use damages arteries and reduces
their ability to carry blood effectively.

Obesity or Overweight
Excess weight can put extra pressure on the legs and restrict healthy blood flow.

Age
Being over 60 increases the risk, as blood vessels naturally become more prone to damage over time.

Family History
A history of cardiovascular disease is linked to higher rates of CLI.

Lifestyle Factors
Physical inactivity and poor diet can contribute to arterial disease and CLI risk.