Showing papers by "Manel Sabaté published in 2008"

Drug eluting and bare metal stents in people with and without diabetes: collaborative network meta-analysis

Abstract: Objective To compare the effectiveness and safety of three types of stents (sirolimus eluting, paclitaxel eluting, and bare metal) in people with and without diabetes mellitus. Design Collaborative network meta-analysis. Data sources Electronic databases (Medline, Embase, the Cochrane Central Register of Controlled Trials), relevant websites, reference lists, conference abstracts, reviews, book chapters, and proceedings of advisory panels for the US Food and Drug Administration. Manufacturers and trialists provided additional data. Review methods Network meta-analysis with a mixed treatment comparison method to combine direct within trial comparisons between stents with indirect evidence from other trials while maintaining randomisation. Overall mortality was the primary safety end point, target lesion revascularisation the effectiveness end point. Results 35 trials in 3852 people with diabetes and 10 947 people without diabetes contributed to the analyses. Inconsistency of the network was substantial for overall mortality in people with diabetes and seemed to be related to the duration of dual antiplatelet therapy (P value for interaction 0.02). Restricting the analysis to trials with a duration of dual antiplatelet therapy of six months or more, inconsistency was reduced considerably and hazard ratios for overall mortality were near one for all comparisons in people with diabetes: sirolimus eluting stents compared with bare metal stents 0.88 (95% credibility interval 0.55 to 1.30), paclitaxel eluting stents compared with bare metal stents 0.91 (0.60 to 1.38), and sirolimus eluting stents compared with paclitaxel eluting stents 0.95 (0.63 to 1.43). In people without diabetes, hazard ratios were unaffected by the restriction. Both drug eluting stents were associated with a decrease in revascularisation rates compared with bare metal stents in people both with and without diabetes. Conclusion In trials that specified a duration of dual antiplatelet therapy of six months or more after stent implantation, drug eluting stents seemed safe and effective in people both with and without diabetes.

Tailoring treatment with tirofiban in patients showing resistance to aspirin and/or resistance to clopidogrel (3T/2R). Rationale for the study and protocol design.

Abstract: To assess whether glycoprotein IIb/IIIa inhibition using tirofiban in low risk patients undergoing percutaneous coronary intervention (PCI) may reduce the risk of periprocedural myocardial infarction compared to standard care in poor responders to aspirin and/or clopidogrel We will enroll patients at ten European sites or more to participate in the Tailoring Treatment with Tirofiban in patients showing Resistance to aspirin and/or Resistance to clopidogrel (3T/2R) study with a pre-specified sample size of 240 patients out of 1,100 or more who will undergo screening The primary outcome measure is troponin I or T elevation ratio at least three times the upper limit of normal within 48 h after completion of the PCI The results of 3T/2R study will evaluate whether tailored intensification of anti-platelet treatment based on poor individual response to oral anti-platelet agents may modulate the risk of periprocedural myocardial infarction during PCI Our findings attempt at unraveling a new era of individualized anti-platelet treatment through the use of point-of-care assessment

Sirolimus‐eluting stents versus bare‐metal stents in patients with in‐stent restenosis: Results of a pooled analysis of two randomized studies

Abstract: Background: Treatment of patients with in-stent restenosis (ISR) remains a challenge. We sought to compare results of sirolimus-eluting stents (SES) with those of bare-metal stents (BMS) in patients with ISR. Methods: The results obtained in the stent arm of two randomized studies were analyzed. The RIBS I study (450 patients with ISR) allocated 224 patients to BMS; the RIBS II study (150 patients with ISR) allocated 76 patients to SES. Complete 1-year follow-up was obtained in all 300 patients treated with stents. Results: Although inclusion/exclusion criteria were identical in the two studies, when compared with patients in the BMS group, patients in the SES arm had more adverse baseline characteristics, more diffuse lesions, and smaller vessels. However, late angiographic findings including in-segment recurrent restenosis rate (11 vs. 38%, P < 0.001), minimal lumen diameter (2.52 vs. 1.63 mm, P < 0.001), and late loss (0.13 vs. 1.04 mm, P < 0.001) were significantly better after SES. The 1-year event-free survival was also significantly improved in the SES group (88 vs. 78%, P < 0.05), as the result of a lower requirement for repeated revascularizations (10.5 vs. 19.6%, P < 0.05). Prespecified subgroup analyses were consistent with the main outcome measures. After adjusting for (a) imbalances in baseline characteristics (restenosis OR 0.11 [95% confidence interval (CI) 0.03–0.36]; adverse events hazard ratios (HR) 0.33 [95% CI 0.13–0.84]) and (b) the propensity score (restenosis OR 0.08 [95% CI 0.03–0.28]; adverse events HR 0.24 [95% CI 0.09–0.66]), results of the SES group were superior to those obtained in the BMS group. Conclusions: When compared with BMS, SES improved the long-term clinicaland angiographic outcome of patients with ISR. © 2008 Wiley-Liss, Inc.

Assessment of potential relationship between wall shear stress and arterial wall response after bare metal stent and sirolimus-eluting stent implantation in patients with diabetes mellitus

Abstract: Background Wall shear stress (WSS) has been associated with neointimal hyperplasia (NIH) following bare metal stent (BMS) implantation. Drug-eluting stents (DES) almost abolish NIH. Conversely, diabetes mellitus amplifies NIH response. The association between WSS and arterial wall response following DES and BMS implantation in diabetic patients remains to be evaluated. Methods The study involved 20 diabetic patients randomized to BMS (n = 9) or sirolimus-eluting stent (SES; n = 11) implantation in native coronary arteries. A computational fluid dynamic model applied 3D intravascular ultrasound (IVUS) and two-plane angiographic to measure WSS (Pa). IVUS assessments were performed post-procedure and at 9-months follow-up. The target segment encompassed the stent plus 5 mm distal and proximal edges. A total of 93 subsegments were evaluated: in-stent segments divided in three subsegments (proximal, mid and distal; n = 60) and proximal and distal edges (n = 33). Results Stent length was similar between BMS (17.4 ± 7.3 mm) and SES (19.8 ± 6.8 mm) groups. NIH was observed in all BMS subsegments (n = 27) versus one subsegment in the SES group (n = 33). WSS ranged from 0.52 to 4.20 Pa in the BMS and from 0.42 to 3.06 Pa in the SES group. There was no correlation between WSS and NIH in either stent group. In addition, there were no correlation between the change of external elastic membrane (EEM) or plaque growth at the edges and WSS. Conclusion WSS was not associated with NIH after implantation of SES or BMS in diabetic patients. Plaque growth or the change of EEM at the edges were not associated with WSS either.

Angiographic and 3D intravascular ultrasound assessment of overlapping bare metal stent and three different formulations of drug-eluting stents in patients with diabetes mellitus

Abstract: Objectives The aim of this study was to examine the impact of overlapping bare-metal stent (BMS) and three different formulations of drug-eluting stent (DES) on intimal hyperplasia (IH) response of patients with diabetes mellitus (DM).

Fractional Flow Reserve in Diabetics: Does It Have an Expiry Date?

Abstract: Assessing the clinical importance of intermediate coronary stenosis, defined as a luminal obstruction of 40% to 70%, is a challenge for the interventional cardiologist. Coronary angiography correlates poorly with the functional importance of epicardial coronary disease, especially in patients with stenosis at the threshold of significance. Post-mortem studies have demonstrated that the coronary lumen area only decreases when atherosclerotic plaque values are above 40%. This event is due to the vessel undergoing positive remodeling during the atherosclerotic process. 1 Another potential source of error lies in the actual methodology used in calculating the severity of coronary stenosis. Thus, the percentage of stenosis is normally calculated as the ratio between the minimum luminal diameter at the site of obstruction and a reference diameter considered “normal,” that is, without disease. 2 Obviously, in the case of diffuse disease, it is very difficult to establish a disease-free reference diameter, which can lead to underestimating the degree of coronary obstruction. Other sources of error are stenosis in tortuous arteries, in bifurcations, with overlapping branches, or highly focal “diaphragm-like” stenosis. This is compounded by the not inconsiderable degree of variation between observers in the qualitative calculation of the degree of obstruction. The calculation of the fractional flow reserve (FFR) has helped to resolve many of these limitations. The FFR is defined as the ratio between the peak coronary flow in the stenotic artery and the peak coronary flow in the same vessel in the theoretical absence of obstruction. 3,4 This should be calculated during maximum arteriolar vasodilation, which establishes the minimum myocardial resistance in the area under study. This is usually achieved by the

Reserva fraccional de flujo en diabéticos. ¿Tiene fecha de caducidad?

Abstract: La determinacion de la relevancia clinica de las estenosis coronarias intermedias, definidas como aquellas con una obstruccion luminal entre el 40 y el 70%, representa un desafio para el cardiologo intervencionista. La angiografia coronaria tiene una pobre correlacion con la importancia funcional de la enfermedad coronaria epicardica, sobre todo en los casos con estenosis en el limite de la significacion. Estudios post mortem han demostrado que la luz coronaria solo se reduce a partir de una carga de placa aterosclerotica de hasta un 40%. Este fenomeno se debe al remodelado positivo que experimenta el vaso durante el proceso aterosclerotico1. Otra potencial fuente de error estriba en la propia metodologia que se emplea en el calculo de la severidad de las estenosis coronarias. Asi, el porcentaje de estenosis suele ser el cociente entre el diametro luminal minimo a nivel de la obstruccion y un diametro de referencia que se considera «normal», sin enfermedad2. Obviamente, en el caso de enfermedad difusa se hace muy dificil determinar un diametro de referencia libre de enfermedad, lo que puede hacer que se subestime el grado de obstruccion coronaria. Otras fuentes de error son las estenosis en arterias tortuosas, en bifurcaciones, con solapamiento de ramas o estenosis muy focales en «diafragma». A todo ello se debe sumar un grado no despreciable de variabilidad entre observadores en el calculo cualitativo del grado de obstruccion. El calculo de la reserva fraccional de flujo (RFF) ha ayudado a resolver muchas de estas limitaciones. La RFF se define como el cociente entre el flujo coronario maximo que se consigue en la arteria estenotica y el flujo coronario maximo en el mismo vaso en ausencia de obstruccion3,4. Este calculo debe Reserva fraccional de flujo en diabeticos. ?Tiene fecha de caducidad?