Resultados clínicos inmediatos y alejados del implante de stents metálicos no recubiertos: ¿Se justifica un reemplazo total por los stents liberadores de drogas? / Acute and long-term clinical results of bare metal coronary stenting

Background: Since the introduction of stents in 1994, improved clinical results have boosted the development of coronary angioplasty in Chile. Drug eluting stents, that have a reduced rate of restenosis, are being increasingly used. Aim: To assess the acute and long-term results of bare metal stent implantation. Patients and Methods: Acute and long-term clinical, procedural and angiographic results were assessed in non acute myocardial infarction patients undergoing coronary stent implantation between August 1996 and December 2003. Results: During the study period, 932 patients aged 30 to 87 years (194 women) had at íeast one stent implanted. Twenty two percent were diabetic, 33 percent had recent myocardial infarction, 53 percent unstable angina and 22 percent stable angina. Angiographic and clinical success were 99.6 percent and 98.2 percent, respectively. In hospital death was 0.5 percent. During a mean follow-up of 19.1 months, all cause mortality was 3.9 percent, cardiac death 1.9 percent and survival free of major cardiac ischemic events was 85.3 percent. Only 6.4 percent of lesions underwent target vessel revascularization (TVR). Independent predictors of TVR were previous surgery, íeft anterior descending artery, small post stent minimum luminal diameter. Ostial location, in-stent restenosis, and younger age were non significant predictors. Conclusions: Acute and long-term results of bare metal stents in this population were excellent. An intriguingly low rate of TVR was seen. Selective bare metal stenting should continue in lesions and patients with a low risk of clinical restenosis.

Resultados tardíos del tratamiento percutáneo de la reestenosis intrastent con el uso de stents con drogas: un estudio colaborativo / Percutaneous treatment of intra stent restenosis using drug eluting stents: late results in a multicenter study

Introducción. La proliferación neointimal es la causa de la reestenosis coronaria intra stent (RIS). Recientemente, el implante de stents liberadores de drogas (DES) ha emergido como una alternativa efectiva de tratamiento endovascular. Material y método. Seleccionamos pacientes con RIS de stents no recubiertos tratados con DES en forma consecutiva en 3 centros chilenos. Luego del alta los pacientes fueron seguidos por al menos 12 meses. Resultados. De 21 pacientes (19 por ciento mujeres) entre 47 y 91 años tratados por al menos una lesión coronaria con RIS, 33,3 por ciento eran diabéticos y 14,3 por ciento tenían cirugía coronaria previa. Se presentaron de preferencia con síndromes coronarios agudos y la mayoría tenía enfermedad de 1 vaso (71,4 por ciento). Se trató sólo 1 lesión con RIS, implantándose en 15 pacientes DES recubierto con Sirolimus y en 6 con Paclitaxel. El largo promedio de stent implantado fue de27,7 mm (13-51 mm). Se obtuvo éxito en todos los casos y no hubo complicaciones isquémicas intrahospitalarias. Durante el seguimiento, sólo 2 pacientes presentaron reestenosis intrastent y uno de ellos, un anciano, falleció en forma súbita en el seguimiento. El 90 por ciento se mantuvo libre de eventos isquémicos en el seguimiento. Conclusión. El implante de DES aparece como una alternativa efectiva en el tratamiento de la RIS.

Background. Neointimal proliferation causes coronary intrastent restenosis (ISR). Recently, drug eluting stents(DES) have emerged as an effective therapeutic approach to treat ISRMethods. Consecutive patients from 3 centers with in stent restenosis after bare metal stent implantation were treated with DES. Patients were followed for 12 months after discharge.Results. Of 21 patients (19 percent females), 47 to 91 years old, with one or more intrastent restenosis, diabetes was present in 33 percent and previous coronary artery surgery in 14 percent. Most patients presented with acute coronary syndromes and 71 percent had single vessel disease. Only one lesion in each patient was treated with DES implantation, 15 with paclitaxel and 6 with sirolimus stents. Mean stent length was 27.7 mm (13-51). The procedure was successful in all patients and no ischemic complications were observed prior to discharge. During follow up 2 patients developed new intra stent restenosis and one of them died suddenly. 90 percent of patients were free from ischemic events at the end of follow up. Conclusion. DES appears to be an effective therapy to treat intra stent restenosis.