Chronic limb threatening ischemia
Chronic limb threatening ischemia | |
---|---|
Other names | Critical limb ischemia, limb threat |
Chronic limb threatening ischemia (CLTI), also known as critical limb ischemia (CLI), is an advanced stage of peripheral artery disease (PAD). It is defined as ischemic rest pain, arterial insufficiency ulcers, and gangrene. The latter two conditions are jointly referred to as tissue loss, reflecting the development of surface damage to the limb tissue due to the most severe stage of ischemia. Compared to the other manifestation of PAD, intermittent claudication, CLI has a negative prognosis within a year after the initial diagnosis, with 1-year amputation rates of approximately 12% and mortality of 50% at 5 years and 70% at 10 years.[1]
CLI was conceived to identify patients at high-risk for
Signs and symptoms
Critical limb ischemia includes rest pain and tissue loss.[citation needed]
Rest pain
Rest pain is a continuous burning
Tissue loss
Tissue loss is the development of
]Diagnosis
Critical limb ischemia is diagnosed by the presence of ischemic rest pain, and an ulcers that will not heal or gangrene due to insufficient blood flow.
Other factors which may point to a diagnosis of critical limb ischemia are a Buerger's angle of less than 20 degrees during Buerger's test, a capillary refill of more than 15 seconds or diminished or absent pulses.[citation needed]
Critical limb ischemia is different from
Emerging Diagnostic Approaches
Other diagnostic approaches for CLI under development or that have recently been introduced include different angiographic and imaging techniques, as well as the use of biosensors.[4]
2D perfusion imaging is a software analysis package that can be incorporated into a standard
Fluorescence angiography enables the visualization of regional blood flow using a charge-coupled camera. A 2016 study determined that it “is a valuable tool in visualizing real-time procedural outcomes and providing additionally useful information on regional tissue perfusion.” [6]
Biosensors measuring oxygen levels subcutaneously in the feet of CLI patients have been developed. Initial studies show these sensors may have value in predicting wound healing in CLI patients.[7] One such sensing system, known as Lumee Oxygen, manufactured by Profusa Inc, attained European Regulatory approval in 2020.[8]
Treatment
Treatment mirrors that of other symptoms of peripheral artery disease, and includes modifying risk factors, revascularization via vascular bypass or angioplasty, and in the case of tissue loss, wound debridement.[citation needed] A randomised trial involving people with chronic limb threatening ischaemia who needed revascularisation below the knee found that offering endovascular therapy first led to better outcomes (fewer deaths and amputations) than offering vein bypass first (among people who were eligible for both surgeries).[9][10]
Research
As of 2015 pCMV-vegf165, a gene-therapy was being studied in critical limb ischemia.[11] In 2014, a trial was started to better understand the best revascularization technique for CLI. As of 2017, it had enrolled nearly half of the 2100 people needed to complete the trial.[12] A similar study, BASIL 2 (Bypass Versus Angio plasty in Severe Ischaemia of the Leg), is being conducted in the United Kingdom.[13]
References
- PMID 20117502.
- PMID 24126108.
- ^ PMID 31401843.
- S2CID 218490284.
- PMID 32284859.
- PMID 26994959.
- ^ Hudson, Jocelyn (2020-01-30). "Profusa Lumee oxygen platform may improve clinical management of patients with CLI". Vascular News. Retrieved 2023-09-01.
- ^ "Profusa Receives CE Mark Approval to Market the Wireless Lumee® Oxygen Platform for Continuous, Real-Time Monitoring of Tissue Oxygen". BioSpace. Retrieved 2023-09-01.
- ISSN 0140-6736.
- ^ "Arterial blockages below the knee: which treatment is best at restoring blood flow?". NIHR Evidence. 13 December 2023.
- S2CID 13443907.
- PMID 27402237.
- PMID 26739146.
External links
- Cochrane Peripheral Vascular Diseases Review Group Archived 2015-02-23 at the Wayback Machine