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Rafael Beyar

Publications and source records attributed to Rafael Beyar.

At least 19 recordsLinked to original sources

Stent deployment failure: reasons, implications, and short- and long-term outcomes.

Stents have revolutionized percutaneous coronary interventions (PCI), impacting on both acute and long-term results. However, despite improvements in stent design, stent deployment failure is not an unusual event. The aim of the present study was to assess the frequency and causes of stent deployment failure, as well as the outcome of these patients. Between 1997 and 2001, a total of 3,537 patients underwent stent-assisted PCI and delivery of 5,275 stents was attempted. In the majority of patients (118; 78.1%), stenting was performed as provisional; in the remaining 33 (21.8%) as a bailout procedure. A total of 175 (3.3%) stents in 151 (4.3%) patients failed. Failure to deliver the stent to the lesion site was the main cause in 139 patients (92%) and failure either to expand adequately the stent or premature disengagement of the stent from the balloon in only 12 patients (8%). Peripheral stent embolization occurred in 10 (0.3%) patients. Deployment of a different stent in place of the failed one was attempted in 122 patients and was successful in the majority (108; 88.5%). In-hospital major adverse cardiac events were observed in six patients (4%): three patients required emergency coronary artery bypass surgery, two had a myocardial infarction (MI), and one patient underwent urgent repeat coronary intervention. At a mean follow-up of 32.2 +/- 17.7 months, 22 major adverse cardiac event occurred in 17 patients (11.2%): 1 cardiac death, 3 patients had an MI, and 18 patients required target vessel revascularization. One-year event-free survival for the whole group was 91.2%. Patients with stent embolization did not have any major adverse cardiac or vascular events. Thus, the rate of stent deployment failure in our series was 3.3%, mainly due to failure to deliver the stent to the site. Another stent was successfully deployed in the majority of cases and these patients had favorable short- and long-term outcomes.

Aged↗

Stenting in acute myocardial infarction: in hospital and long-term follow-up.

BACKGROUND: Coronary stenting was recently introduced as a primary intervention for acute myocardial infarction. Several randomized controlled studies have shown that stenting may be superior to balloon angioplasty for the treatment of AMI. However, routine stenting may also cause deterioration of coronary flow. OBJECTIVE: To analyze the clinical characteristics and the outcome of patients who were treated with stenting for AMI in our center in the recent era of stenting. METHODS: Fifty-five patients with AMI were treated by stent implantation between January 1998 and December 1999. Adverse clinical events were recorded, including death, recurrent infarction, coronary artery bypass grafting, cerebrovascular accident, and target vessel revascularization. In-hospital, 1 month, 6 month and 1 year follow-up was performed in all patients. Repeat coronary angiography was performed according to clinical indications. RESULTS: Baseline angiographic results showed Thrombolysis in Myocardial Infarction (TIMI) 0 flow in 39 patients (70.9%), TIMI I flow in no patient and TIMI II/III flow in 16 patients (29.1%). TIMI grade 3 flow was achieved in 90.9% of patients at the end of the procedure. In-hospital mortality rate was 5.4% (2.1% in patients without cardiogenic shock). There was no evidence of re-infarction or TVR. The rates of bleeding complication (all of them minor), CVA, and CABG were 9.1%, 3.6% and 1.8% respectively. The 6 month mortality rate remained the same. Rates of re-infarction, restenosis, TVR and CABG were 3.6%, 14.5%, 14.5% and 5.4% respectively. The 1 year mortality rate was 7.3%. Restenosis rate was 18% and CABG 7.3%. One year event-free survival was 70.9%. CONCLUSIONS: This study suggests that stenting is a safe and effective mode of therapy in the setting of AMI associated with a high rate of revascularization and a low short and long-term outcome.

Angioplasty, Balloon, Coronary↗

Comparison of two platelet glycoprotein IIb/IIIa inhibitors, eptifibatide and abciximab: outcomes, complications and thrombocytopenia during percutaneous coronary intervention.

BACKGROUND: Platelet glycoprotein IIb/IIIa inhibitors have significantly reduced the incidence of 30-day ischemic events during percutaneous coronary interventions (PCI). However, each of the three currently available agents has different pharmacological characteristics, safety, efficacy and costs. There has not been a direct comparison between eptifibatide and abciximab in the rates of major adverse cardiac events, major complications and thrombocytopenia. METHODS: A total of 642 consecutive patients underwent PCI at our institution between January 2000 and December 2001 and were treated with either eptifibatide (n = 342) or abciximab (n = 300) during the procedure. The selection of the IIb/IIIa inhibitor was arbitrary and left to the discretion of the operator. Complete blood counts were performed by routine protocol on all patients 2 and 4 hours after initiation of the drug. We analyzed the in-hospital clinical outcomes and the incidence of thrombocytopenia in this cohort. RESULTS: Baseline clinical and angiographic characteristics and concomitant drug treatment were similar between the 2 groups, except for a higher incidence of diabetes in the eptifibatide group. The rates of in-hospital death (1.2% eptifibatide group versus 1.0% abciximab group; p = 0.7), stroke (0% for both groups), target vessel revascularization (1.2% eptifibatide group versus 1.0% abciximab group; p = 0.8) and major bleeding complications (1.7% eptifibatide group versus 0.7% abciximab group; p = 0.2) were similar between the 2 groups. Thrombocytopenia was more frequent in the abciximab-treated patients (6%, versus 0% in the eptifibatide group; p < 0.001), including 5 patients who developed profound thrombocytopenia (< 20,000 cells/mm3). CONCLUSION: Both agents, eptifibatide and abciximab, proved to have the same rates of in-hospital major adverse cardiac events, bleeding and vascular complications. Abciximab therapy was associated with a significantly higher incidence of thrombocytopenia within 4 hours of drug initiation, which prompted immediate drug discontinuation, but was not associated with increased risk of bleeding, vascular or other complications.

Abciximab↗

Comparison of bypass surgery and stenting for the treatment of multivessel disease: results from the ARTS trial in Israel.

BACKGROUND: The Arterial Revascularization Therapies Study was a multicenter, randomized trial designed to compare percutaneous coronary intervention with stenting versus coronary artery bypass graft surgery in 1,205 patients with multivessel coronary artery disease. The most appropriate type of treatment for these patients is still a matter of considerable debate. OBJECTIVES: To evaluate the clinical characteristics of patients enrolled in the ARTS trial in Israel in comparison to those worldwide, and to assess the 1 year outcome in these patients. METHODS: Between April 1997 and June 1998, a total of 1,205 patients with multivessel coronary artery disease, who were considered to be equally treatable with both modalities, were randomized to either stenting (n = 600) or CABG (n = 605) at 67 centers around the world. In Israel, 53 patients at four participating medical centers were randomized to either PCI with stents (n = 27) or CABG (n = 26). RESULTS: Clinical and angiographic characteristics were similar in the two groups, except for a significantly higher incidence of diabetic patients in Israel who were randomized to CABG, compared to those worldwide (35% vs. 16%, P = 0.01). Also, there were more patients with unstable angina in Israel (63 vs. 37%, P = 0.006). At 1 year follow-up, overall mortality and cerebrovascular accident rates were similar between the two groups and equivalent to results obtained around the world. There was a significantly higher incidence of myocardial infarction rates in patients randomized to stenting in Israel compared to patients worldwide (7.4 vs. 5.3%, P = 0.01) or to patients randomized to CABG in Israel (7.4 vs. 0%, P = 0.006). Similar to the overall ARTS results, there was a higher incidence of repeat revascularization procedures in patients assigned to the PCI with stenting arm (22.2 vs. 3.8%, P = 0.004) compared to those randomized to CABG, respectively. CONCLUSIONS: The results of this analysis of the Israeli ARTS population indicate that coronary stenting and bypass surgery yield similar findings with regard to mortality and stroke and are comparable to those obtained in the whole study group. Likewise, coronary stenting was associated with an increased incidence of repeat revascularization procedures as compared to CABG. However, patients in Israel randomized to stenting had a higher rate of myocardial infarction as compared to the overall results and to patients who underwent CABG in Israel. The present analysis provides important data for the safety and efficacy of either stenting or bypass surgery in treating patients with multivessel disease in Israel.

Angioplasty, Balloon, Coronary↗

Stenting very small coronary narrowings (< 2 mm) using the biocompatible phosphorylcholine-coated coronary stent.

Published data regarding stenting very small arteries are still limited. The BiodivYsio stent is a new stent coated with phosphorylcholine, a biocompatible molecule designed to reduce the formation of thrombus and potentially the risk of restenosis. The feasibility, safety, and efficacy of implantation of the 2.0 mm coated coronary stent were prospectively studied. We studied 97 patients from three centers who underwent elective, urgent, or bailout implantation of 106 BiodivYsio mini-stents (2.0 mm) in 101 lesions. Forty percent of lesions had unfavorable characteristics (type B2 or C) and 16% had thrombus and/or chronic total occlusion. Successful stent deployment was achieved in 100/101 lesions (99%). MLD increased from 0.49 +/- 0.31 mm to 1.89 +/- 0.41 mm and diameter stenosis decreased from 89% +/- 7% to 5.6% +/- 6%. Small vessel stenting was the only procedure in 71% patients. There was one acute stent thrombosis case. During 6-month follow-up, none died, one had MI, and one was referred to CABG due to nontarget lesion progression. Angiographic restenosis that required target lesion revascularization was performed in 8/18 that had catheterization due to chest pain or significant ischemia. Most patients improved in their clinical symptoms. The rate of major adverse cardiac events was 4.1% at 30-day and 10.3% at 6-month follow-up. This initial clinical experience indicates that the implantation of 2.0 mm stents coated with phosphorylcholine appears to be safe and efficacious in the treatment of complex coronary lesions and is associated with low target vessel revascularization rate in spite of the very small vessel diameter.

Adult↗

A prospective single-center registry for the use of intracoronary gamma radiation in patients with diffuse in-stent restenosis.

Based on single-center prospective registry data, the study evaluates short- and long-term results of intracoronary gamma radiation in patients with diffuse in-stent restenosis in the reality of routine clinical practice. Percutaneous coronary intervention and subsequent catheter-based irradiation with iridium-192 was performed in 84 vessels (81 patients) with diffuse in-stent restenosis. Repeat coronary angiography was performed in 35 patients with clinical restenosis. With a mean follow-up of 12.0 +/- 0.5 months, major adverse cardiac events were observed in 29 (34.5%) patients, including 2 cases of cardiac death, 3 myocardial infarctions, 21 target lesion revascularizations, and 4 target vessel revascularizations. Five of six patients with total occlusion of the target vessel at baseline developed target lesion restenosis. Late total occlusion of the target vessel was observed in four patients. The 1-year event-free survival rate was 69.8%. Total occlusion of the target vessel at baseline was the single independent predictor of cardiac events at 1-year follow-up (P < 0.001). In patients with a target lesion in the left anterior descending artery, predictors of cardiac events also included female sex (P = 0.014), current smoking (P = 0.014), stenting during brachytherapy session (P = 0.02), and smaller reference vessel diameter at baseline (P = 0.01). The results of our registry are similar to those of randomized trials. As applied in routine clinical practice, intracoronary gamma radiation is a feasible, safe, and effective tool in the treatment of diffuse in-stent restenosis. Late events in the entire group were predicted by total occlusion at baseline.

Aged↗

Staged versus one-step approach for multivessel percutaneous coronary interventions.

BACKGROUND: Percutaneous coronary interventions (PCIs) in patients with multivessel coronary artery disease (CAD) may be staged or performed in a single session. No data exist about the relative safety and efficacy of these 2 strategies. Our aim was to compare short-term and long-term outcomes of patients with multivessel CAD who underwent PCI in 1 versus 2 sessions. METHODS AND RESULTS: The study included 264 consecutive patients who underwent treatment in our center during 1997 and 1998. PCI was conducted in a single session in 129 patients and was staged in 135 patients. The mean interval between the sessions in the staged group was 45.6 +/- 22.3 days. The rates of major adverse cardiac events (MACEs) during in-hospital stay did not differ significantly between the staged (combined for both stages) and nonstaged groups (2.2% vs 4.6%; P =.28). A trend for lower event rates at 30-day (2.9% vs 6.9%; P =.13) and 1-year follow-up (26.1 vs 35.9; P =.08) favored the staged arm. Diameter stenosis > or =50% was found in 17% of patients in the staged group in the second session and was successfully retreated in most of them. No MACE occurred between the sessions. Multivariate analysis identified staging of the procedure as a single independent predictor of MACE at 1-year follow-up (P =.05). CONCLUSION: Our results suggest that a practical staging strategy within 4 to 8 weeks is safe and allows for identification and treatment of potential excessive proliferative response in the previously intervened lesions during the second procedure.

Angina Pectoris↗

Editorial.

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Editorial↗

Editorial.

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Journal Article↗

Editorial.

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Editorial.

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Journal Article↗