Peripheral Microvascular Resistance as a Predictor for Limb Salvage

Efficacy of the peripheral flow reserve

Salvaging a threatened limb is the key therapeutic objective for patients with critical limb
 ischemia, and the achievement of limb salvage is an independent predictor of patient
 morbidity and mortality. Despite successful primary endovascular or surgical intervention,
 the corresponding symptoms of rest pain and/or non-healing ulceration in some patients may
 continue, and amputation in these patients is unavoidable. It is hypothesized that the
 functional integrity of the peripheral vascular microcirculation may be impaired in these
 patients. However, there are currently no techniques that allow direct quantification and
 visualization of the microcirculation due to the micro-vessel invisibility under angiography.
 
 In the coronary circulation, coronary flow reserve (CFR) indicates the capacity for maximal
 hyperemic blood flow and reveals impaired coronary microvascular function. Studies have shown
 the clinical significance of measuring microvascular resistance to predict myocardial salvage
 after myocardial infarction. The study will explore whether this concept of coronary flow
 reserve can be applied peripherally to patients with critical limb ischemia in order to
 determine whether measuring peripheral vascular flow reserve can determine the integrity of
 the microcirculation to predict limb salvage after endovascular intervention.