Cobalt Chromium or Stainless Steel Balloon-Expandable Bare Metal Stents for Iliac Occlusive Disease?

Background: To compare the performance of a new-generation cobalt-chromium balloon-expandable bare metal stent with a stainless steel platform for the treatment of iliac occlusive disease. Methods: Consecutive patients treated for symptomatic iliac occlusive disease between 2014 and 2021 with the cobalt-chromium Dynetic-35 or the stainless steel Dynamic platform were retrospectively evaluated. Outcome measures included technical success, device- or procedure-related death, clinically-driven target lesion revascularization (CD-TLR), primary patency, and major index limb amputation up to 12 months. Results: In total, 222 Cobalt chromium (CC) stents were used in 159 patients (34.6% female; mean age 66.9 +/- 9.5 years) for the treatment of 216 lesions, while 234 iliac lesions of 182 patients (34.6% female; mean age 66.3 +/- 9.9 years) were treated with 252 stainless steel (SS) stents. The mean lesion length (30.2 +/- 12.8 mm vs 28.7 +/- 22.5 mm, p=0.36) and the mean calcification grade (2.0 vs 1.9, p=0.07) did not differ significantly between the 2 groups. Patients treated by the CC platform were more frequently on statins (p<0.001), whereas more active smokers and subjects with higher Rutherford class underwent a SS deployment (p<0.001). Technical success was significantly higher in the SS group (100% vs 97.3%; p=0.01). This was due to longitudinal deformation or stent dislocation after passing the Dynetic-35 with endovascular material. After 1 year, no difference was found following CC and SS stent deployment in terms of device- or procedure-related deaths (0.6% vs 1.1%, p=0.99), target limb amputations (1.9% vs 1.6%, p=0.99), primary patency (91.3% vs 93.5%), and CD-TLR (6.5% vs 2.8% p=0.07). Conclusions: Through 1 year, cobalt-chromium and stainless steel balloon-expandable stents are safe and effective in the treatment of iliac occlusive disease. Enhanced attention should be given passing the cobalt-chromium stent with endovascular devices to avoid procedural complications.