Lesion types and device characteristics that predict distal embolization during percutaneous lower extremity interventions

Objective Distal embolization (DE) during percutaneous lower extremity revascularization (LER) may cause severe clinical sequelae. To better define DE, we investigated which lesion types and treatment modalities increase the risk for embolization. Methods A prospective registry of LER from 2004 to 2009 was reviewed. All cases with runoff evaluated before and after intervention were included. Angiograms and operative reports were reviewed for evidence of DE. Interventions included percutaneous transluminal angioplasty (PTA), with or without stent placement, and atherectomy with four different devices. Chi-square analysis and Fisher's exact test were used to assess significance. Patency rates were calculated using Kaplan-Meier analysis and compared using log-rank analysis. Results There were 2137 lesions treated in 1029 patients. The embolization rate was 1.6% (34 events). Jetstream (Pathway, Kirkland, Wash) and DiamondBack 360 (Cardiovascular Systems Inc, St Paul Minn) devices had a combined embolization rate of 22% (8 of 36), 4 of 18 (22%) in each group, which was significantly higher than with PTA alone (5 of 570, 0.9%), PTA and stent (5 of 740, 0.7%), SilverHawk (ev3, Plymouth, Minn) atherectomy (14 of 736, 1.9%), and laser atherectomy (2 of 55, 3.6%; P < .001). There was a significantly higher rate of embolization for in-stent restenosis (6 of 188, 3.2%) and chronic total occlusions (15 of 615, 2.4%) compared with stenotic lesions (13 of 1334, 0.9%; P = .01). The embolization rate was significantly higher in Transatlantic Inter-Society Consensus (TASC) II C and D lesions compared with TASC A and B lesions (P = .018). DE rates were not affected by preoperative runoff status (P = .152). Patency was restored at the completion of the procedure in 32 of 34 cases of DE. The 24-month primary patency, assisted primary patency, and secondary patency in the DE group was 54.0% ± 11.9%, 70.0% ± 10.3%, and 73.2% ± 10.3%, respectively, and was 44.4% ± 1.7%, 61.5% ± 1.7%, and 68.2% ± 1.6%, respectively, when embolization did not occur (P > .05). Limb salvage was 72.6% ± 3.1% in lesions in which no DE occurred vs 83.3% ± 15.2% in lesions in which DE occurred (P = .699). Conclusions DE is a rare event that occurs more often with the Jetstream and DiamondBack 360 devices. In-stent and complex native lesions are at higher risk for DE. DE is typically reversible with endovascular techniques and has no effect on patency rates and limb salvage.