New data from a propensity matched prospective study suggest the Supera stent (Abbott Vascular) delivers superior results when compared to older generation nitinol stents in chronic total occlusions of the femoropopliteal artery. The use of the interwoven stent delivered better results in terms of freedom from in-stent restenosis and major adverse events.
The data were presented by Konstantinos Katsanos, assistant professor of Interventional Radiology, Imaging Sciences, School of Medicine, Patras University Hospital, Rion, Greece, at the CIRSE annual meeting (10–14 September 2016, Barcelona, Spain). Chronic total occlusions, Katsanos said, constitute approximately one third of all infrainguinal lesions, and this rate can rise to 50–60% in more complex critical limb ischaemia patients. He added, “Chronic total occlusions are difficult to recanalise and you often end up in the subintimal space, therefore achieving lower crossing and success rates. These lesions are more prone to recoil and to requiring stenting. They often present a higher plaque volume, are frequently calcified, and higher rates of restenosis and stent failure have been implied by some evidence.”
The SUPERFAST investigators hypothesised that because of its mechanical characteristics the Supera biomimetic stent may conform and perform better than old nitinol stents in femoropopliteal chronic total occlusion lesions. The inclusion criteria included any femoropopliteal segment (including P2 and P3), subintimal or intraluminal recanalisation, and at least a single vessel run-off. The prospective data were then matched to a historical cohort of patients treated with older generation stents.
After matching, 53 Supera patients were then compared to 53 control patients. There was no statistical difference in terms of baseline characteristics, Rutherford class (4.3 for both groups), number of popliteal lesions, rate of subintimal recanalisation and total occlusion length (15±10cm in the control group and 14.3±10.4cm in the Supera group).
Moving on to the results, Katsanos said that at 390 days freedom from in-stent restenosis (50% threshold on Duplex ultrasound) was 88% with Supera and 56% in the control group (a 60% reduction in the risk of restenosis). The investigators performed further restenosis analyses. Looking at the superficial femoral artery and P1 segment only (excluding P2 and P3), the results were similar to the original analysis (88% vs. 57%); when looking at intraluminal recanalisation only (excluding subintimal) there was 100% patency with Supera and 60% patency in the control group.
In terms of Rutherford class deterioration, 85% of Supera patients were free from recurrent limb ischaemia (three target lesion revascularisation cases) against 65% with other nitinol stents (six target lesion revascularisation cases), and 98% of Supera patients and 91% of other device patients were free from major amputation. Survival rates were 84% with Supera and 80% for other stents, a non-statistical significant difference. For the composite endpoint of freedom from target stent reintervention, limb major amputation and recurrent limb ischaemia, 86% of Supera patients and 70% of other device patients were free from major adverse events, a 53% risk reduction.
Katsanos concluded that “in this highly complex patient population Supera reduced the hazard of vessel restenosis and recurrent symptomatic ischaemia by approximately 60%”. He said, “Most interestingly, there were fewer major amputations with Supera at one year. It also reduced the composite endpoint of major adverse events by approximately 55%. Based on our experience Supera should be the stent of choice for complex femoropopliteal chronic total occlusions.”
SUPERSUB: Subintimal recanalisation
In another presentation at CIRSE, Mariano Palena, Interventional Radiology Unit, Policlinico Abano Terme, Abano Terme, Italy, presented results of the SUPERSUB study, an investigation of the long-term outcomes of subintimal revascularisation with Supera for long femoropopliteal chronic total occlusions in critical limb ischaemia patients.
From January 2014 to August 2015, 34 consecutive critical limb ischaemia patients with TASC C and D chronic total occlusions were included in this prospective, single-centre, single-arm study. Patients underwent stenting with Supera after subintimal occlusion crossing.
The primary efficacy endpoint was one-year stent patency and freedom from target lesion revascularisation. The primary safety endpoint was the composite rate of freedom from death due to any cause, major amputations, and target lesion revascularisation at one year. Secondary endpoints at 12 months were stent integrity, clinical improvement, amputation-free survival, quality of life, and cost efficiency.
The mean lesion length was 27.9±10.2cm. Acute technical success was obtained in 100% of patients. Primary patency was 94.1% and freedom from target lesion revascularisation was 97.1%. Limb salvage was 100%. Clinical improvement was observed in 100% of patients (tcpO2 increased from 12.7±6.2 to 54.8±8.4mmHg, p<0.0001), Rutherford category shifted to class 0 (p<0.0001), and improvement in quality of life metrics went from 0.46±0.33 to 0.89±0.16 (p<0.0001) according to the EQ5D-3L questionnaire. There were no stent fractures. Amputation-free survival was 82.4%.
In conclusion, Palena said, subintimal revascularisation with Supera in patients with critical limb ischaemia and long femoropopliteal occlusions has been shown to outperform efficacy and modify safety performance goals previously set for patients with less severe disease.