- Evidence of significant SFA disease involving the most symptomatic limb established by noninvasive vascular testing (ankle-brachial index [ABI] <0.9, toe brachial Index [TBI] of <0.6. If ABI>1.4, SFA systolic acceleration time >140 milliseconds); computed tomographic angiography, or magnetic resonance angiography confirming at least a 60% stenosis of the SFA.