Peripheral arterial disease (PAD) is a condition caused by obstruction of the peripheral arteries, leading to an increased risk for cardiovascular events and premature death. The classic PAD symptom is intermittent claudication or walking pain, but notably two-thirds of all patients are asymptomatic. Early diagnosis and treatment using noninvasive vascular tests are crucial to save lives.
With an increasing population of patients with diabetes that is often asymptomatic and with falsely normal or high ankle-brachial index (ABI) values, detecting PAD has changed in recent years. For reliable non-invasive vascular tests, look instead to toe pressure, pulse volume recording (PVR) and transcutaneous oxygen (tcpO2).
Why is the diagnosis more complex in patients with diabetes?
- Longer & multiple lesions
- Less collateral flow
- Below the knee
- More aggressive
- Microcirculatory issues
- Perfusion deficit in foot more severe
Critical limb-threatening ischemia (CLTI)
CLTI is a more severe form of PAD with significant mortality, morbidity and higher use of health care resources. The distal blood flow and microcirculatory function are severely compromised resulting in rest pain, ischemic ulcers and gangrene. CLTI is a clinical diagnosis but should be supported by objective vascular testing. Due to the high risk of calcified vessels with falsely normal or high ABI, even in non-diabetics, toe pressures, PVR and tcpO2 must be used in all patients.
- 30% of all patients with confirmed CLTI have normal or high ABI.
- All patients with suspected CLTI should have toe pressure or tcpO2 to assess perfusion according to WIfI classification.
- tcpO2 is the best modality to grade the level of ischemia and prioritize vascular procedures.
- Due to the complex nature of CLTI, all patients that undergo vascular intervention should be reassessed with toe pressure or tcpO2 to guarantee restored perfusion.