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Eric J Topol

Publications and source records attributed to Eric J Topol.

At least 109 records · Page 6Linked to original sources
PubMed2004

Comparison of bivalirudin versus heparin during percutaneous coronary intervention (the Randomized Evaluation of PCI Linking Angiomax to Reduced Clinical Events [REPLACE]-1 trial).

To assess the efficacy of the direct thrombin inhibitor bivalirudin relative to heparin during contemporary coronary intervention, 1,056 patients who underwent elective or urgent revascularization were randomized in a large-scale pilot study to receive heparin (70 U/kg initial bolus) or bivalirudin (0.75 mg/kg bolus, 1.75 mg/kg/hour infusion during the procedure). All patients received aspirin; pretreatment with clopidogrel was encouraged, and glycoprotein (GP) IIb/IIIa blockade was at the physician's discretion. Stents were placed in 85% of patients; 72% received a GP IIb/IIIa inhibitor, and 56% were pretreated with clopidogrel. Activated clotting times were higher among patients randomized to bivalirudin than among those given heparin before device activation (median 359 vs 293 seconds, p <0.001). The composite efficacy end point of death, myocardial infarction, or repeat revascularization before hospital discharge or within 48 hours occurred in 5.6% and 6.9% of patients in the bivalirudin and heparin groups, respectively (p = 0.40). Major bleeding occurred in 2.1% versus 2.7% of patients randomized to bivalirudin or heparin, respectively (p = 0.52). This trial represents the largest prospective dataset of bivalirudin administered concomitantly with planned GP IIb/IIIa blockade and provides evidence of the safety and efficacy of this combined antithrombotic approach.

Aged↗
PubMed2004

Propensity analysis of long-term survival after surgical or percutaneous revascularization in patients with multivessel coronary artery disease and high-risk features.

BACKGROUND: Although most randomized clinical trials have suggested that long-term survival rates after percutaneous coronary intervention (PCI) or surgical multivessel coronary revascularization (CABG) are equivalent, some post hoc analyses in high-risk groups and adjustment for severity of coronary disease have suggested higher mortality after PCI. METHODS AND RESULTS: We studied 6033 consecutive patients who underwent revascularization in the late 1990s. PCI was performed in 872 patients; 5161 underwent CABG. Half the patients had significant left ventricular dysfunction or diabetes. Propensity analysis to predict the probability of undergoing PCI according to 22 variables and their interactions was used. The C-statistic for this model was 0.90, indicating excellent discrimination between treatments. There were 931 deaths during 5 years of follow-up. The 1- and 5-year unadjusted mortality rates were 5% and 16% for PCI and 4% and 14% for CABG (unadjusted hazard ratio, 1.13; 95% CI, 1.0 to 1.4; P=0.07). PCI was associated with an increased risk of death (propensity-adjusted hazard ratio, 2.3; 95% CI, 1.9 to 2.9; P<0.0001). This difference was observed across all categories of propensity for PCI and in patients with diabetes or left ventricular dysfunction. Other independent predictors of mortality (P< or =0.01 for all) were renal dysfunction, age, diabetes mellitus, chronic lung disease, peripheral vascular disease, left main trunk stenosis, and extent of coronary disease (Duke angiographic score). CONCLUSIONS: In patients with multivessel coronary artery disease and many high-risk characteristics, CABG was associated with better survival than PCI after adjustment for risk profile.

Aged↗
PubMed2004

Thrombocytopenia caused by abciximab or tirofiban and its association with clinical outcome in patients undergoing coronary stenting.

BACKGROUND: Thrombocytopenia is a possible complication of treatment with glycoprotein (GP) IIb/IIIa antagonists during percutaneous coronary interventions, but it is not clear whether different GP IIb/IIIa inhibitors carry a different risk of thrombocytopenia, and its relation to clinical outcome is unknown. METHODS AND RESULTS: We analyzed data from the Do Tirofiban and Reopro Give Similar Efficacy Outcomes (TARGET) study, which compared the safety and efficacy of abciximab and tirofiban in patients undergoing coronary stenting. Platelets were measured at baseline and 6 and 24 hours after the beginning of treatment. Thrombocytopenia (nadir platelet count <100x10(9) cells/L) developed in 2.4% of patients treated with abciximab and 0.5% of those treated with tirofiban (P<0.001). The variables independently associated with thrombocytopenia were treatment with abciximab within the previous 6 months (OR, 4.4; 95% CI, 1.7 to 11.2), baseline creatinine levels of > or =0.8 mg/dL (OR, 3.8; 95% CI, 1.7 to 8.8), previous transient ischemic attack (OR, 3.2; 95% CI, 1.4 to 7.6), female gender (OR, 1.9; 95% CI, 1.2 to 3.1), and history of peripheral vascular disease (OR, 1.78; 95% CI, 1.0 to 3.1). Severe bleeding occurred more frequently in patients with thrombocytopenia (5.1% versus 0.7%, P=0.001), who also more frequently received blood transfusions (6.1% versus 1.4%, P=0.001). At the 30-day follow-up, 2.0% of patients with thrombocytopenia and 0.4% of those without (P=0.022) had died; myocardial infarction occurred in 9.13% versus 6.11% (P=NS); and target vessel revascularization occurred in 6.07% versus 0.60% (P<0.001). CONCLUSIONS: During coronary stenting, abciximab and other risk factors are independently associated with thrombocytopenia. Regardless of the cause, thrombocytopenia is associated with more ischemic events, bleedings, and transfusions.

Abciximab↗
PubMed2004

Assessing the impact of population stratification on genetic association studies.

Population stratification refers to differences in allele frequencies between cases and controls due to systematic differences in ancestry rather than association of genes with disease. It has been proposed that false positive associations due to stratification can be controlled by genotyping a few dozen unlinked genetic markers. To assess stratification empirically, we analyzed data from 11 case-control and case-cohort association studies. We did not detect statistically significant evidence for stratification but did observe that assessments based on a few dozen markers lack power to rule out moderate levels of stratification that could cause false positive associations in studies designed to detect modest genetic risk factors. After increasing the number of markers and samples in a case-cohort study (the design most immune to stratification), we found that stratification was in fact present. Our results suggest that modest amounts of stratification can exist even in well designed studies.

Case-Control Studies↗
PubMed2004

Aspirin dose and six-month outcome after an acute coronary syndrome.

OBJECTIVES: This study was designed to compare the efficacy of low and intermediate aspirin doses in acute coronary syndromes. BACKGROUND: Little is known of the comparative efficacy of low and intermediate aspirin doses in this setting. METHODS: We compared six-month death, myocardial infarction (MI), and stroke in patients with unstable angina or acute MI discharged while receiving low (<150 mg) or intermediate (> or =150 mg) aspirin therapy in the GUSTO IIb and PURSUIT trials (n = 20,521). We used multivariable analysis and performed a propensity analysis in order to adjust for baseline imbalances between the groups. RESULTS: Aspirin doses <150 mg were prescribed to 29.9% (6,128) of patients. By six months, 6.4% of the patients (1,310 of 20,521) had a primary event, 6.2% of the patients receiving <150 mg and 6.6% of the patients receiving aspirin doses > or =150 mg (hazard ratio [HR] 1.06 [95% confidence interval (CI) 0.94 to 1.19], p = 0.35). After adjusting for baseline imbalances and the propensity score for discharge aspirin dose, there was no effect of aspirin dose on the composite end point at six months (HR 0.92 [95% CI 0.79 to 1.07], p = 0.28). However, the higher aspirin dose was associated with a reduction in six-month MI (HR 0.79 [95% CI 0.64 to 0.98], p = 0.03). The outcome was similar when patients were matched on the basis of the propensity score for aspirin dose (HR for death/MI/stroke 0.94 [95% CI 0.80 to 1.12], p = 0.51), although stroke occurred significantly more frequently among patients receiving the higher aspirin dose (HR 1.74 [95% CI 1.01 to 3.02] p = 0.05) and the effect on MI was no longer apparent. CONCLUSIONS: Although these data are non-randomized, they suggest that the aspirin dose upon discharge may influence the clinical course after unstable angina or acute MI.

Aged↗
PubMed2004

Meta-analysis of randomized trials of percutaneous transluminal coronary angioplasty versus atherectomy, cutting balloon atherotomy, or laser angioplasty.

OBJECTIVES: We conducted a systematic overview (meta-analysis) of randomized trials of balloon angioplasty versus coronary atherectomy, laser angioplasty, or cutting balloon atherotomy to evaluate the effects of plaque modification during percutaneous coronary intervention. BACKGROUND: Several mechanical approaches have been developed that ablate or section atheromatous plaque during percutaneous coronary interventions to optimize acute results, minimize intimal injury, and reduce complications and restenosis. METHODS: Sixteen trials (9,222 patients) constitute the randomized controlled experience with atherectomy, laser, or atherotomy versus balloon angioplasty with or without coronary stenting. Each trial tested the hypothesis that ablative therapy would result in better clinical or angiographic results than balloon dilation alone. RESULTS: Short-term death rates (<31 days) were not improved by the use of ablative procedures (0.3% vs. 0.4%, odds ratio [OR] 0.94 [95% confidence interval 0.46 to 1.92]), but periprocedural myocardial infarctions (4.4% vs. 2.5%, OR 1.83 [95% CI 1.43 to 2.34]) and major adverse cardiac events (5.1% vs. 3.3%, OR 1.54 [95% CI 1.25 to 1.89]) were increased. Angiographic restenosis rates (6,958 patients) were not improved with the ablative devices (38.9% vs. 37.4%, OR 1.06 [95% CI 0.97 to 1.17]). No reduction in revascularization rates (25.2% vs. 24.5%, OR 1.04 [95% CI 0.94 to 1.14]) or cumulative adverse cardiac events rates up to one year after treatment were seen with ablative devices (27.8% vs. 26.1%, OR 1.09 [95% CI 0.99 to 1.20]). CONCLUSIONS: The combined experience from randomized trials suggests that ablative devices failed to achieve predefined clinical and angiographic outcomes. This meta-analysis does not support the hypothesis that routine ablation or sectioning of atheromatous tissue is beneficial during percutaneous coronary interventions.

Angioplasty, Balloon, Coronary↗
PubMed2004

Effect of clopidogrel pretreatment on inflammatory marker expression in patients undergoing percutaneous coronary intervention.

Platelets play an important role in the inflammatory response. In a nonrandomized comparison, we examined the effect of clopidogrel pretreatment on platelet inflammatory marker expression in patients undergoing percutaneous coronary intervention (PCI). Platelet expression of the inflammatory markers CD40 ligand (L) and CD62 P-selectin (P) and serum levels of interleukin-6 and CD40L were compared in patients pretreated (>24 hours before PCI) or not pretreated with clopidogrel. Blood samples were obtained before and after the procedure, and from 18 to 24 hours later. Marker expression in resting and adenosine diphosphate (ADP) (50 micromol/L) and thrombin receptor activating peptide (TRAP) (10 micromol/L) activated samples was quantified by flow cytometry. Serum CD40L and interleukin (IL)-6 levels were determined by enzyme-linked immunosorbent assay. Seventy-nine patients were recruited into the study. Forty-two percent were pretreated with clopidogrel for a median of 5 days (range 1 to 1,325). Clopidogrel pretreatment was associated with lower ADP-activated platelet CD40L expression in baseline and postprocedural samples. Similarly, platelet CD62P expression at all time points in ADP-activated and in baseline and postprocedural TRAP-activated samples was lower in patients pretreated with clopidogrel. These differences remained after multivariate adjustment between the groups. Serum CD40L levels increased from 2.13 +/- 2.37 ng/ml at baseline to 4.77 +/- 3.86 ng/ml at 18 to 24 hours after the procedure (p <0.0001). Similarly, serum IL-6 levels increased at 18 to 24 hours after the procedure (14.8 +/- 42.0 pg/ml before vs 25.5 +/- 36.0 pg/ml at 18 to 24 hours after the procedure, p <0.0001). Clopidogrel pretreatment did not affect serum IL-6 or CD40L levels. Thus, clopidogrel pretreatment reduces platelet inflammatory marker expression in patients undergoing PCI.

Aged↗
PubMed2004

Molecular and functional differences induced in thrombospondin-1 by the single nucleotide polymorphism associated with the risk of premature, familial myocardial infarction.

A serine (Ser-700) amino acid rather than an asparagine (Asn-700) at residue 700 of thrombospondin-1 has been linked to an increased risk for development of premature, familial heart attacks. We now have identified both functional and structural differences between the Ser-700 and Asn-700 thrombospondin-1 variants. The Ser-700 variant increased the rate and extent of platelet aggregation and showed increased surface expression on platelets compared with the Asn-700 variant. These differences could be ascribed to an enhanced interaction of the Ser-700 variant with fibrinogen on the platelet surface and are consistent with a prothrombotic phenotype in Ser-700 individuals. The Ser-700 variant thrombospondin-1 was conformationally more labile than the Asn-700 variant as demonstrated by increased susceptibility to proteolytic digestion and enhanced susceptibility to unfolding by denaturants. These data suggest a potential molecular and cellular basis for a genetic risk factor associated with early onset myocardial infarction.

Asparagine↗
PubMed2004

Outcome of acute ST-segment elevation myocardial infarction in diabetics treated with fibrinolytic or combination reduced fibrinolytic therapy and platelet glycoprotein IIb/IIIa inhibition: lessons from the GUSTO V trial.

OBJECTIVES: We studied the outcome of diabetics enrolled in the Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) V trial to assess whether the combination of half-dose reteplase and abciximab provides any propitious benefits over standard fibrinolytic therapy in diabetic patients. BACKGROUND: Diabetics with acute ST-segment elevation myocardial infarction (MI) have a worse outcome compared with nondiabetics. Higher-risk patients are usually more likely to benefit from advances in medical therapy. METHODS: We analyzed diabetic patients enrolled in the GUSTO V trial to assess the outcome of those randomized to the combination of half-dose reteplase and abciximab versus those randomized to reteplase. We also evaluated whether any differences existed in presentation and outcome of MI among the diabetics versus the nondiabetics enrolled in the study. RESULTS: The trial enrolled 13782 nondiabetics and 2633 diabetics. Compared to nondiabetics, diabetics had a significantly higher mortality at 30 days (8.5% vs. 5.1%, p < 0.001) and at 1 year (12.7% vs. 7.5%, p < 0.001). Among the diabetic subset, no significant difference existed in the incidence of 30-day (8.8% vs. 8.2%, p = 0.52) or 1-year mortality (13.0% vs. 12.4%, p = 0.62) among patients randomized to reteplase compared to those receiving combination of abciximab and reteplase. The incidence of reinfarction (2.5% vs. 4.3%, p = 0.013), recurrent ischemia (11.8% vs. 14.9%, p = 0.017), and urgent revascularization (10.9% vs. 13.3%, p = 0.055) at seven days was lower in diabetics treated with the combination therapy. CONCLUSIONS: Compared to nondiabetics, diabetics continue to have a worse outcome with MI. Although combination therapy did not provide a survival benefit, nonfatal ischemic outcomes, including reinfarction, recurrent ischemia, and urgent revascularization, were substantially reduced.

Abciximab↗
PubMed2004

Risk factors for intracranial hemorrhage and nonhemorrhagic stroke after fibrinolytic therapy (from the GUSTO-i trial).

Of 592 patients in the Global Utilization of Streptokinase and tPA for Occluded Arteries-I trial who had a stroke during initial hospitalization, the risk for intracranial hemorrhage was significantly greater in those with recent facial or head trauma (odds ratio 13.0, 95% confidence interval 3.4 to 85.5); dementia was additionally associated with an increased risk for intracranial hemorrhage (odds ratio 3.4, 95% confidence interval 1.2 to 10.2). Because facial or head trauma may greatly influence treatment decisions, this risk factor should be incorporated into models designed to estimate the risks and benefits of fibrinolytic therapy.

Aged↗
PubMed2004

International differences in evolution of early discharge after acute myocardial infarction.

BACKGROUND: Early discharge of low-risk patients with acute myocardial infarction is feasible and can be achieved at no additional risk of adverse events. We aimed to identify the extent to which countries have taken advantage of the opportunity for early discharge. METHODS: The study population consisted of 54174 patients enrolled in GUSTO-I, GUSTO-III, and ASSENT-2 studies (enrollment period 1990-98) in the USA, Canada, Australia, New Zealand, Belgium, France, Germany, Spain, and Poland. We identified patients with uncomplicated acute myocardial infarction who were eligible for early discharge on the basis of previously established criteria, and assessed the extent to which these patients were discharged early--defined as discharged alive within 4 days of admission. The economic consequences (defined as potentially unnecessary hospital days consumed per 100 patients enrolled) were also investigated. FINDINGS: Patients in all European countries had significantly longer stays than did those from non-European countries. Over the study period, the number of eligible patients discharged on or before day 4 increased in the USA, Canada, Australia, and New Zealand. Despite this increase, no more than 40% of patients who were eligible for early discharge were actually discharged early. The rate of early discharge of eligible patients was consistently low (<2%) in Belgium, France, Germany, Spain, and Poland. In ASSENT-2, which is the most recent trial in this study, the number of potentially unnecessary hospital days (per 100 patients enrolled) ranged from 65 in New Zealand to 839 in Germany. INTERPRETATION: Despite more than a decade of research, there is still a lot of variation between countries in international length-of-stay patterns in acute myocardial infarction. The potential for more efficient discharge of low-risk patients exists in all countries investigated, but was especially evident in the European countries included in the study (Belgium, France, Germany, Spain, and Poland).

Acute Disease↗
PubMed2004

The gene encoding 5-lipoxygenase activating protein confers risk of myocardial infarction and stroke.

We mapped a gene predisposing to myocardial infarction to a locus on chromosome 13q12-13. A four-marker single-nucleotide polymorphism (SNP) haplotype in this locus spanning the gene ALOX5AP encoding 5-lipoxygenase activating protein (FLAP) is associated with a two times greater risk of myocardial infarction in Iceland. This haplotype also confers almost two times greater risk of stroke. Another ALOX5AP haplotype is associated with myocardial infarction in individuals from the UK. Stimulated neutrophils from individuals with myocardial infarction produce more leukotriene B4, a key product in the 5-lipoxygenase pathway, than do neutrophils from controls, and this difference is largely attributed to cells from males who carry the at-risk haplotype. We conclude that variants of ALOX5AP are involved in the pathogenesis of both myocardial infarction and stroke by increasing leukotriene production and inflammation in the arterial wall.

5-Lipoxygenase-Activating Proteins↗
PubMed2004

Benefit of clopidogrel over aspirin is amplified in patients with a history of ischemic events.

BACKGROUND AND PURPOSE: The goal of this study was to examine the influence of preexisting symptomatic atherosclerotic disease on subsequent ischemic event rates and compare the efficacy of clopidogrel versus aspirin (acetylsalicylic acid, ASA) in patients with such disease. METHODS: Using the CAPRIE database, we performed multivariate analyses for patients who had symptomatic atherosclerotic disease (ischemic stroke [IS] or myocardial infarction [MI]) in their medical history before enrollment in the Clopidogrel Versus Aspirin in Patients at Risk of Ischemic Events (CAPRIE) trial. Two composite end points were used: (1) IS, MI, or vascular death and (2) IS, MI, or rehospitalization for ischemia. RESULTS: In the CAPRIE population, prior IS and MI each were statistically significant predictors of subsequent ischemic events. Compared with the overall population, patients with preexisting symptomatic atherosclerotic disease had elevated event rates for the end point of IS, MI, or vascular death; 3-year rates were 20.4% with clopidogrel and 23.8% with ASA (absolute risk reduction, 3.4%; 95% CI, -0.2 to 7.0; number needed to treat, 29; relative risk reduction, 14.9%; P=0.045). Similar results were obtained for the end point of IS, MI, or rehospitalization for ischemia; 3-year event rates were 32.7% with clopidogrel and 36.6% with ASA (absolute risk reduction, 3.9%; 95% CI, -0.4 to 8.1; number needed to treat, 26; relative risk reduction, 12.0%; P=0.039). CONCLUSIONS: CAPRIE patients with a history of prior symptomatic atherosclerotic disease had a high rate of subsequent ischemic events. The absolute benefit of clopidogrel over ASA seemed to be amplified in such high-risk patients.

Aged↗
PubMed2004

Premature myocardial infarction novel susceptibility locus on chromosome 1P34-36 identified by genomewide linkage analysis.

The most frequent causes of death and disability in the Western world are atherosclerotic coronary artery disease (CAD) and acute myocardial infarction (MI). This common disease is thought to have a polygenic basis with a complex interaction with environmental factors. Here, we report results of a genomewide search for susceptibility genes for MI in a well-characterized U.S. cohort consisting of 1,613 individuals in 428 multiplex families with familial premature CAD and MI: 712 with MI, 974 with CAD, and average age of onset of 44.4+/-9.7 years. Genotyping was performed at the National Heart, Lung, and Blood Institute Mammalian Genotyping Facility through use of 408 markers that span the entire human genome every 10 cM. Linkage analysis was performed with the modified Haseman-Elston regression model through use of the SIBPAL program. Three genomewide scans were conducted: single-point, multipoint, and multipoint performed on of white pedigrees only (92% of the cohort). One novel significant susceptibility locus was detected for MI on chromosomal region 1p34-36, with a multipoint allele-sharing P value of <10(-12) (LOD=11.68). Validation by use of a permutation test yielded a pointwise empirical P value of.00011 at this locus, which corresponds to a genomewide significance of P<.05. For the less restrictive phenotype of CAD, no genetic locus was detected, suggesting that CAD and MI may not share all susceptibility genes. The present study thus identifies a novel genetic-susceptibility locus for MI and provides a framework for the ultimate cloning of a gene for the complex disease MI.

Adult↗
PubMed2004

Invisible showers.

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Angioplasty, Balloon, Coronary↗
PubMed2004

Real-world bare metal stenting: identification of patients at low or very low risk of 9-month coronary revascularization.

The high cost of drug-eluting stents (DESs) has made identification of patients who are at low risk for subsequent revascularization after treatment with bare metal stents (BMSs) highly desirable. Previous reports from randomized trials suffer from biases induced by restricted entry criteria and protocol-mandated angiographic follow-up. Between 1994 and 2001, 5,239 consecutive BMS patients, excluding those with coil stents, technical failure, brachytherapy, staged procedure, or stent thrombosis within 30 days, were prospectively identified from a large single-center tertiary-referral-center prospective registry for long-term follow-up. We sought to identify characteristics of patients with very low (< or = 4%) or low (4-10%) likelihood of coronary revascularization 9 months after BMS. Nine-month clinical follow-up was obtained in 98.2% of patients. Coronary revascularization was required in 13.4% and did not differ significantly by stent type. On the basis of multivariate analysis identifying 11 independent correlates and previous reports, 20 potential low-risk patient and lesion groups (228 +/- 356 patients/groups) were identified (e.g, patients with all of the following: native vessel, de novo, reference diameter > or = 3.5 mm, lesion length < 5 mm, no diabetes, not ostial in location). Actual and model-based outcomes were analyzed. No group had both predicted and observed 9-month revascularization < or = 4% (very low risk). Conversely, 19 of 20 groups had a predicted and observed revascularization rate of 4-10% (low risk). In the real-world setting, the need for intermediate-term revascularization after BMS may be lower than expected, but it may be very difficult to identify patients at very low risk. Conversely, if the benefits of DESs are attenuated in routine practice, many groups of patients treated with BMSs may have nearly comparable results.

Aged↗