Critical Limb Ischaemia

Keywords

■ Peripheral arterial disease (PAD)

■ Atherosclerosis

■ Critical limb ischaemia

What is Critical Limb Ischaemia?

■ Critical limb ischaemia occurs in 5-10% of patients with Peripheral Arterial Disease (PAD), a chronic condition, usually caused by atherosclerosis (Figure 1), that results in lower extremity arterial obstruction and poor circulation. Early stages of PAD are often asymptomatic. As the disease progresses, patients may develop intermittent claudication or chronic limb-threatening ischemia (CLTI)1,2

■ It is characterized by resting lower extremity pain, ulceration, gangrene, increased risk of cardiovascular events, amputation, and death1,2

■ Prevalence is high among elderly patients with PAD affecting between 1520% of individuals over the age of 70 years3

■ As lipids accumulate within vessel walls there is subsequent hardening causing a significant reduction in blood flow to target tissues4

■ The corresponding reduction in oxygenation at peripheral tissue can lead to claudication or resting pain5,6

■ CLTI carries a mortality rate of 20% within 6 months of diagnosis and 50% at 5 years5,6

Diagnosis

■ The diagnosis of CLTI involves clinical findings (such as ischemic rest pain) and objective findings including ankle-brachial pressures

■ (<50 mmHg with rest pain or <70 mmHg with foot ulcer or gangrene), toe systolic pressure (<30 mmHg with rest pain or <50 mmHg with foot ulcer or gangrene), and transcutaneous oxygen pressure (<30 mmHg with foot ulcer or gangrene) (Figure 2)7

Impact

■ The prevalence of CLTI is projected to grow in coming years as the trend in risk factors such as age, diabetes, smoking, and the unknown effects of vaping product use increases

■ The poor clinical prognosis associated with CLTI leads to significant reduction in quality of life (QOL) due to ischemic resting pain, non-healing ulcers, and recurrent infection8

■ Chronic limb ischemia not only affects the patient, but also impacts caregivers who must handle the patient’s lack of mobility, pain control needs, wound care, and other issues

■ Economically, the annual cost of new Medicare patients with CLTI alone is $12 billion9

■ This healthcare cost is largely attributed to high inpatient expenditure, need for complex wound care and interventions, prolonged hospitalizations, and high readmission rates

■ Vascular disease

■ Ankle brachial pressure index (ABPI)

■ Diabetes

Presence of chronic ischemic rest pain plus Ankle pressure <50 mmHg or Toe pressure <30 mmHg

Presence of foot ulcers or gangrene plus Ankle pressure <70 mmHg

Toe systolic pressure <50 mmHg or TcPO2 <30 mmHg