Selective stenting in subintimal angioplasty: analysis of primary stent outcomes

Abstract

Objective: Subintimal angioplasty (SIA) is being increasingly utilized to treat chronic arterial occlusions. The role of stents in SIA is currently unknown. We performed a retrospective review of selective stent use in SIA to assess outcomes and factors affecting these results.

Methods: A retrospective review of patient information--including demographics, indications, procedures, noninvasive studies, and post-procedural events--was performed on our database for patients undergoing SIA in the superficial femoral and popliteal arteries. Outcomes were calculated only on technically successful SIAs using Kaplan-Meier survival analysis. Continuous and non-continuous data were compared using the Student t test and the z test, respectively. Survival curves were compared using log-rank testing for univariate analysis and Cox hazard-regression analysis for multivariate analysis.

Results: Three-hundred-sixty-eight patients (382 limbs) underwent femoral and/or popliteal SIA for critical limb ischemia or disabling claudication from December 1, 2002 through July 31, 2006. Eighty-four limbs (22%) had a stent placed, while 298 (78%) did not receive a stent. Mean follow-up was 11.7 months (range, 0-45 months). One-year primary and secondary patency for stent vs no-stent group was 50% vs 45% (P = .73) and 70% vs 78% (P = .47), respectively. One-year limb salvage rate for the stent vs no-stent group was 85% vs 90% (P = .61). At 2 years, patients receiving a stent are more likely to undergo open bypass than those without a stent (P = .06). Eighty-three patients underwent 84 SIA with stent placement. The mean number of stents for each case was 1.4 +/- 0.7. Univariate analysis revealed that previous ipsilateral bypass surgery significantly decreased 1-year patency: 35% vs 56% (P = .05). SIA performed for disabling claudication had a trend toward improved 1-year patency 58% vs 39% for critical limb ischemia (P = .09). A stent diameter > or =7 mm displayed a trend toward better patency 53% vs 37% for diameter < or =6 mm (P = .08). None of these factors proved significant with multivariate analysis.

Conclusion: Selective stents placed for suboptimal results after subintimal angioplasty produce similar patency rates to primary SIA without stents. Patients receiving stents with prior lower extremity bypass surgery will have worse outcomes than those without. Use of a stent diameter < or =6 mm and indication of critical limb ischemia will likely produce worse results. It appears that other stent variables (location, number, length, and overlap) do not alter patency. Finally, selective stent use after SIA provides excellent limb salvage.