An Algorithm for the Use of Embolic Protection During Atherectomy for Femoral Popliteal Lesions.

OBJECTIVES: This study sought to identify an algorithm for the use of distal embolic protection on the basis of angiographic lesion morphology and vascular anatomy for patients undergoing atherectomy for femoropopliteal lesions.

BACKGROUND: Atherectomy has been shown to create more embolic debris than angioplasty alone. Distal embolic protection has been shown to be efficacious in capturing macroemboli; however, no consensus exists for the appropriate lesions to use distal embolic protection during atherectomy.

METHODS: Patients with symptomatic lower extremity peripheral artery disease treated with atherectomy and distal embolic protection were evaluated to identify potential predictors of DE. Plaque collected from the SilverHawk nose cone subset was sent to pathology for analysis to evaluate the accuracy of angiography in assessing plaque morphology.

RESULTS: Significant differences were found in lesion length (142.1 ± 62.98 vs. 56.91 ± 41.04; p = 0.0001), low-density lipoprotein (82.3 ± 40.3 vs. 70.9 ± 23.2; p = 0.0006), vessel runoff (1.18 ± 0.9 vs. 1.8 ± 0.9; p = 0.0001), chronic total occlusion (131 vs. 10; p = 0.001), in-stent restenosis (33 vs. 6; p = 0.0081), and calcified lesions (136 vs. 65; p < 0.001). In simple logistic regression analysis lesion length, reference vessel diameter, chronic total occlusion, runoff vessels, and in-stent restenosis were found to be strongly associated with macroemboli. Angiographic assessment of plaque morphology was accurate. Positive predictive value of 92.31, negative predictive value of 95.35, sensitivity of 92.31, and specificity of 95.35 for calcium; positive predictive value of 95.56, negative predictive value of 100, sensitivity of 100, and specificity of 92.31 for atherosclerotic plaque. Thrombus/in-stent restenosis was correctly predicted.

CONCLUSIONS: Chronic total occlusion, in-stent restenosis, thrombotic, calcific lesions >40 mm, and atherosclerotic lesions >140 mm identified by peripheral angiography necessitate concomitant filter use during atherectomy to prevent embolic complications.