RESUMEN
ACKGROUND:Scoring balloons produce excellent acute results in the treatment of in-stent restenosis (ISR), fibro-calcific and bifurcation lesions but have not been shown to affect the restenosis rate. A novel paclitaxel-coated scoring balloon (SB) was developed and tested to overcome this limitation.METHODS AND RESULTS:SB were coated with paclitaxel admixed with a specific excipient. Patients at four clinical sites in Germany and one in Brazil with ISR of coronary bare metal stent (BMS) were randomized 1:1 to treatment with either a drug-coated or uncoated SB. Baseline and 6-month follow-up quantitative coronary angiography was performed by an independent blinded core lab and all patients will be evaluated clinically for up to one year. The primary endpoint was angiographic in-segment late lumen loss (LLL). Secondary endpoints included the rate of clinically driven target lesion revascularization (TLR), composite of major adverse cardiovascular events (MACE), stent thrombosis and other variables. Sixty-one patients were randomized (28 uncoated and 33 drug-coated SB); mean age 65 years, males 72%, and presence of diabetes 39%. At 6-month angiography, in-segment LLL was 0.48 ± 0.51 mm in the uncoated SB group versus 0.17 ± 0.40 mm in the drug-coated SB group (P = 0.01; ITT analysis). The rate of binary restenosis was 41% in the uncoated SB group versus 7% in the drug-coated SB group (P = 0.004). The MACE rate was 32% with the uncoated SB vs. 6% in the drug-coated SB group (P = 0.016). This difference was primarily due to the reduced need for clinically driven TLR in the coated SB group (3% vs. 32% P = 0.004)...
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Stents , Stents Liberadores de FármacosRESUMEN
This article addresses current pacing practices and issues. Pacing, sensing, sensing amplifiers, and pacing leads are discussed. Cardiac resynchronization is reviewed. Issues of ventricular pacing avoidance, pacemaker lead infections, ionizing radiation effects on pacing and pacing issues after deterioration and expiration of the patient are considered.
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Estimulación Cardíaca Artificial/métodos , Marcapaso Artificial , Bradicardia/fisiopatología , Bradicardia/terapia , Estimulación Cardíaca Artificial/efectos adversos , Terapia de Resincronización Cardíaca , Electrocardiografía , Electrodos Implantados , Diseño de Equipo , Sistema de Conducción Cardíaco/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Humanos , Marcapaso Artificial/efectos adversos , Calidad de Vida , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/terapiaRESUMEN
Restenosis following interventions in the coronary or peripheral arteries develops over weeks to months. In coronary arteries the restenosis rate has been markedly reduced since the advent of drug-eluting stents. Non-stent-based methods for local drug delivery enable restenosis inhibition without the need for stent implantation, does not permanently change the structure of the vessel, are repeatable, and seems to be applicable where drug-eluting stents provide insufficient protection. Preclinical data indicate that short exposure of the vessel wall to a lipophilic inhibitor of cell proliferation is sufficient for preventing restenosis. Initial evidence to this effect emerged from an investigation of paclitaxel embedded in a matrix that enhances the solubility and release of the agent from the balloon coating as well as its transfer to the vessel wall. Further corroborating data from preclinical and clinical studies demonstrating a reduction in late lumen loss and lower restenosis rates led to the market introduction of a variety of paclitaxel-coated angioplasty balloons. The effectiveness of restenosis inhibition is not determined by the active agent alone. Other factors that are crucial for the effectiveness and safety of drug-coated angioplasty balloons are the formulation containing the agent and the coating technique. In this review we first outline the development of paclitaxel-coated balloons to then provide an overview of the preclinical results obtained with different paclitaxel-coated balloons and finally compare these with the outcome in patients. The article concludes with a short outlook on initial results with a zotarolimus-coated angioplasty balloon.
Asunto(s)
Angioplastia Coronaria con Balón , Reestenosis Coronaria/prevención & control , Stents Liberadores de Fármacos , Paclitaxel/administración & dosificación , Paclitaxel/uso terapéutico , Sistemas de Liberación de Medicamentos , Humanos , Sirolimus/administración & dosificación , Sirolimus/análogos & derivados , Sirolimus/uso terapéuticoRESUMEN
During the last decades considerable advances have been made in intravascular interventions for the treatment of coronary and peripheral arterial disease. However, long-term outcome remains an area of concern in many applications. Restenosis is still a challenge in endovascular medicine and has thus been referred to as the Achilles' heel of percutaneous intervention. Therefore, novel strategies have been developed to overcome this problem. These include drug-eluting stents, though still associated with stent thrombosis and in-stent restenosis, and the more recently introduced non-stent based local drug delivery systems, especially the paclitaxel-eluting balloon. Results of several preclinical and clinical studies indicate that short-term exposure of injured arteries to paclitaxel eluted from regular PTA and PTCA balloons may be sufficient to reduce late lumen loss and restenosis rates during a critical period of time after angioplasty of diseased coronary and peripheral arteries. Although the number of published trials and patients treated is still limited, available data seem to prove that restenosis inhibition by immediate drug release is feasible. This article reviews the rationale for the use of paclitaxel-coated balloons, data from preclinical and clinical studies, and the perspective of drug-coated balloons in peripheral arterial disease.