Purpose: The purpose of this study was to assess the effect of superficial femoral artery (SFA) stenosis morphologic characteristics and lesion location on the rate of atherosclerotic disease progression.
Methods: We identified 19 patients who required arteriography for treatment of critical leg ischemia and who had previously undergone arteriography of that leg when minimal or no symptoms were present. These initial incidental arteriographic evaluations were performed during evaluation of arterial disease in another vascular bed from 4 to 81 months (mean, 32 months) previously. Distinct SFA stenoses or occlusion on the final arteriogram (n = 98) were characterized by their location, length, stenosis severity, and morphologic appearance on the initial arteriogram. The contribution of patient-specific risk factors to disease progression was also assessed.
Results: Stenosis progression occurred independently among multiple lesions within the same patient (negligible intraclass correlation coefficient, r = 0.06). Lesions in the adductor canal region were more likely to occlude than lesions elsewhere in the SFA (adjusted odds ratio = 10.7; p = 0.03). Severity of initial lesion stenosis also was predictive of occlusion (adjusted odds ratio = 1.8; p = 0.04). However, most progressing lesions (93%) actually arose in areas of initially mild disease (stenoses < 50%) despite more severe initial lesions elsewhere. Increasing age (p = 0.023) and previous contralateral leg bypass (p = 0.036) were also associated with increasing rates of lesion progression. Smooth-asymmetric lesions progressed 11% more slowly than other lesion types (p = 0.003).
Conclusions: Our analysis of atherosclerotic SFA lesion progression in patients with critical ischemia shows that initial stenosis severity was associated with higher occlusion rates and that smooth-asymmetric lesions progressed more slowly than lesions with other morphologic characteristics. Severe stenoses usually arose from minimally diseased regions and progressed more rapidly than preexisting, more highly stenotic lesions. Most SFA occlusions resulted from disease progression in the adductor canal region whether or not antecedent lesions were seen on arteriography and whether or not more severe stenoses were initially present elsewhere. Increased age and history of previous contralateral bypass were patient-specific predictors of lesion progression.