Outcomes of the Use of a Superflexible Nitinol Stent in the Popliteal Artery

Background: The long-term primary patency rates for percutaneous transluminal angioplasty using first and second generation stents for the treatment of the popliteal artery have been disappointing. However, results with the new nitinol stents seem promising. Our objective was to evaluate short-term clinical outcomes using the superflexible nitinol stent in the treatment of atherosclerotic lesions in popliteal segments. Methods: Retrospective longitudinal study conducted from April to December 2013. Population characteristics, procedure-related data and imaging tests were assessed at 6 months. Stent patency and limb salvage rates were obtained. Results: A total of 14 patients with mean age of 73 ± 11 years were included, of which 50% were male and 64.3% diabetic. All patients had trophic lesions in the treated limbs. The arteriographic lesions were classified according to the criteria of the Trans-Atlantic Inter-Society Consensus (TASC) criteria as TASC B and C inequal proportions. In the assessment of below-the-knee runoff, 78.6% of the patients had only one distal pervious artery, of which the fibular artery was the most frequently observed. The stent landing zone was the mid segment of the popliteal artery in 57.1% of the cases and the distal segment, crossing the knee joint, in the remaining patients. During the 6 month follow-up there were no stent fractures. The primary patency rate was 85.7% and the limb salvage rate was 100%. Conclusions: In our study, angioplasty using the super flexible nitinol stent demonstrated to be safe and effective for the treatment of atherosclerotic lesions of the popliteal artery. DESCRIPTORS: Stents. Angioplasty. Popliteal artery. Instituto Dante Pazzanese de Cardiologia, São Paulo, SP, Brazil. Correspondence to: Patrick Bastos Metzger. Avenida Dr. Dante Pazzanese, 500 – Vila Mariana – CEP: 04012-180 – São Paulo, SP, Brazil E-mail: [email protected] Received: 3/5/2014 • Accepted: 5/23/2014 RESUMO Resultados do Uso de Stent de Nitinol Superflexível em Artérias Poplíteas Introdução: As taxas de patência primária no longo prazo para a angioplastia transluminal percutânea, com implante de stents de primeira e segunda geração, no tratamento da artéria poplítea, têm sido desapontadoras. No entanto, resultados com novos stents de nitinol parecem promissores. Nosso objetivo foi avaliar desfechos clínicos no curto prazo do uso de stents de nitinol superflexíveis no tratamento de lesões ateroscleróticas nos segmentos poplíteos. Métodos: Estudo retrospectivo, longitudinal, realizado no período de abril a dezembro de 2013. Foram avaliados as características populacionais, os dados do procedimento e os exames de imagem aos 6 meses, sendo obtidas as taxas de patência do stent e de salvamento de membro. Resultados: Incluímos nesta análise, 14 pacientes, com idade de 73 ± 11 anos, 50% do sexo masculino e 64,3% diabéticos. Todos os pacientes apresentavam lesão trófica nos membros tratados. As lesões arteriografias foram classificadas pelo critério Trans-Atlantic Inter-Society Consensus (TASC) em B e C em igual proporção. Na avaliação do leito de escoamento, 78,6% dos pacientes possuíam apenas uma artéria pérvia, sendo a artéria fibular a mais frequentemente observada. As zonas de aterrissagem dos stents foram o segmento médio da artéria poplítea em 57,1% dos casos e, nos demais, o segmento distal da artéria, cruzando a articulação do joelho. Durante o seguimento de 6 meses, não foram observadas fraturas dos stents. A taxa de patência primária foi de 85,7% e a de salvamento do membro foi de 100%. Conclusões: A angioplastia com uso de stent de nitinol superflexível demonstrou ser segura e efetiva no tratamento das lesões ateroscleróticas da artéria poplítea. DESCRITORES: Stents. Angioplastia. Artéria poplítea. Original Article Rodrigues et al. Angioplasty of Popliteal Artery Rev Bras Cardiol Invasiva. 2014;22(2):161-7 162 L ower-limb revascularization with the use of stents for the treatment of peripheral obstructive arterial disease (POAD) is usually restricted to segments not submitted to external compression, or to regions without mobility, due to the complex mechanisms of forces acting on the vessels, with generation of considerable biomechanical stress, especially in the popliteal artery.1 Even today, the results are not ideal, with stents of first and second generation showing patency rates below those of conventional surgical treatment. The rates of stent fracture, when the device is implanted in the popliteal artery, range from zero to 65% in different cohorts.2 A new generation of more flexible and resistant stents3,4 has shown comparable results, in the short-and medium-term, versus surgical treatment, which is still considered the standard technique for the treatment of these lesions.1 With the development of third-generation superflexible stents, endoluminal therapy has increasingly replaced surgical revascularization.4-6 This study aimed to evaluate the clinical outcomes in the short-term use of superflexible nitinol stents in the treatment of atherosclerotic lesions of popliteal segments.