Research priorities
5.1	What are the expected procedural, hemodynamic, and clinical outcomes of revascularization across the spectrum of infrainguinal disease severity? Better evidence is needed to validate the GLASS, particularly for endovascular strategies in intermediate (II) and severe (III) stages of infrainguinal disease.
5.2	What is the effect of severe IM and pedal arch disease on revascularization outcomes in CLTI? Is there a clinically useful way to grade this level of disease?
5.3	Is there evidence that other measures, such as outflow bed resistance or below-knee runoff scores, are predictive of procedural or clinical outcomes? How do these compare with target path lesion complexity assessed by angiography?
5.4	Is there a simple, reproducible method for quantification of calcification that has predictive value for infrainguinal interventions?
5.5	Are there specific patient factors (eg, demographic or comorbidity) associated with anatomic patterns of disease in CLTI?
5.6	Are there anatomic patterns of disease in which an endovascular approach is futile?
5.7	How does lesion morphology (eg, concentric vs eccentric) influence treatment success for different endovascular interventions?
5.8	Is there a correlation between GLASS stage and clinical presentation (WIfI)?
5.9	What is the comparative value of direct (angiosome based) vs indirect revascularization in the setting of tissue loss, and how should it drive selection of the preferred TAP? Is this specific to wound location or WIfI stage?