Biomedical subjects

Gregg W Stone

Publications and source records attributed to Gregg W Stone.

At least 145 records · Page 8Linked to original sources

PubMed2004

Favorable effect of gamma-radiation for in-stent restenosis: effect of diabetes on angiographic and clinical outcomes.

The purpose of this study was to examine the effect of vascular brachytherapy with gamma-radiation (gamma-RT) in patients with diabetes mellitus (DM) with coronary in-stent restenosis (ISR). In the Washington Radiation for In-Stent Restenosis (WRIST) trial, 130 patients with ISR were treated with (192)Ir or placebo. Of the patients enrolled, 44 (34%) had DM (18 of them treated with gamma-RT and 26 with placebo). Gamma-radiation therapy of ISR in diabetics resulted in similar procedural success and in-hospital outcome compared to nondiabetics. At 6-month follow-up, both DM and non-DM patients treated with gamma-RT had significantly lower target lesion revascularization (TLR), target vessel revascularization, and major adverse cardiac event rates compared to placebo. DM remains a powerful predictor of TLR and major adverse cardiac events even after treatment of ISR with gamma-RT.

Adult↗

PubMed2004

Luminal narrowing due to intramural hematoma shift from left anterior descending coronary artery to left circumflex artery.

This case report demonstrates subacute luminal narrowing 20 days after balloon angioplasty in the left anterior descending coronary artery due to an intramural hematoma. Stenting was performed and resulted in side-branch compromise caused by squeezing the hematoma from the left anterior descending coronary artery into the left circumflex artery. Another stent was deployed to treat the stenosis in the left circumflex artery.

Adult↗

PubMed2004

Successful use of the frontrunner catheter in the treatment of in-stent coronary chronic total occlusions.

Percutaneous intervention of coronary chronic total occlusion (CTO) from in-stent restenosis (ISR) is hindered by difficulty to cross the lesion with conventional guidewires. This study describes the successful treatment of five cases of CTOs from ISR using the Frontrunner controlled blunt microdissection catheter. Four of the five cases had failed previous attempts of percutaneous intervention with conventional guidewires. The Frontrunner catheter successfully facilitated the placement of guidewire into the distal true lumen in all five cases. The median crossing time was 10 min. No subintimal delivery of guidewire or vascular perforation was observed. TIMI 3 flow was achieved in all target vessels after further balloon angioplasty or stenting. The Frontrunner device is a safe and effective tool in the treatment of CTOs from ISR.

Aged↗

PubMed2004

Improved clinical outcomes with abciximab therapy in acute myocardial infarction: a systematic overview of randomized clinical trials.

BACKGROUND: Investigations of glycoprotein (GP) IIb/IIIa inhibition in primary percutaneous coronary intervention (PCI) have suggested the efficacy of abciximab in improving clinical and angiographic outcomes, but sample-size limitations and variability in trial design preclude the ability to generalize these results to a broader patient population. METHODS: Meta-analytic techniques were used to evaluate clinical outcomes from randomized trials comparing GP IIb/IIIa inhibition with placebo or control therapy in primary PCI for acute myocardial infarction (MI). RESULTS: In 3266 patients, treatment with abciximab significantly reduced the 30-day composite end point of death, reinfarction, or ischemic or urgent target-vessel revascularization (TVR; odds ratio [OR], 0.54; 95% CI, 0.40-0.72), with trends toward reduced 30-day death and death or reinfarction. Abciximab resulted in an increased likelihood of major bleeding (OR, 1.74; 95% CI, 1.11-2.72). By 6 months, abciximab significantly reduced the occurrence of death, reinfarction, or any TVR (OR, 0.80; 95% CI, 0.67-0.97), and there were positive trends favoring a decrease in mortality alone and the composite of death or reinfarction. CONCLUSIONS: Treatment with abciximab significantly reduces early adverse ischemic events, a clinical benefit that is maintained at 6-month follow-up. These findings support the use of adjunctive GP IIb/IIIa inhibition in primary PCI.

Abciximab↗

PubMed2004

Impact of ST-segment resolution after primary angioplasty on outcomes after myocardial infarction in elderly patients: an analysis from the CADILLAC trial.

BACKGROUND: Age is a strong independent predictor of outcomes after primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). Whether lower rates of reperfusion success contribute to the poor prognosis in elderly patients is unknown. METHODS: A formal ST-segment analysis substudy was performed in 695 patients undergoing primary PCI for AMI in the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial. Reperfusion success (determined by the magnitude of ST-segment elevation resolution [STR] after PCI) was evaluated in 4 age groups: <50 years (n = 163), >or=50 to <60 years (n = 187), >or=60 to <70 years (n = 194), and >or=70 years (n = 151). RESULTS: There were no differences in the age groups for angiographic procedural success (>91% in all, P =.6), postprocedural Thrombolysis in Myocardial Infarction grade 3 flow (>94%, P =.8), and the proportions of patients with complete, partial, or absent STR (P >.8). However, rates of 30-day mortality (0.6%, 1.1%, 3.6%, 6.0%, respectively) and major adverse cardiac events (MACE; 2.5%, 4.8%, 6.2% 9.3%, respectively) increased with age. Rates of mortality and MACE were also inversely related to the magnitude of STR. Absent STR (hazard ratio, 3.00; 95% CI, 1.37-6.58; P =.006) and age (hazard ratio, 1.34; 95% CI, 1.01-1.77; P =.04) were independent predictors of 30-day MACE by using multivariable modeling. CONCLUSIONS: Lack of effective myocardial reperfusion is not a contributory mechanism responsible for the high morbidity and mortality rates observed in elderly patients. Nevertheless, advanced age and absent STR are both independent predictors of adverse outcomes after primary PCI, emphasizing the importance of successful reperfusion in the elderly population.

Abciximab↗

PubMed2004

Coordinated series of studies to evaluate characteristics and mechanisms of acute coronary syndromes in high-risk patients randomly assigned to enoxaparin or unfractionated heparin: design and rationale of the SYNERGY Library.

Clinical trials and accompanying substudies in patients with acute coronary syndromes (ACS) have over the last several years yielded a wealth of knowledge about the pathophysiology and management of this high-risk condition. The Superior Yield of the New strategy of Enoxaparin, Revascularization, and GlYcoprotein IIb/IIIa inhibitors (SYNERGY) trial is a large-scale, randomized, controlled trial evaluating the effect of enoxaparin and unfractionated heparin on death and myocardial infarction in high-risk patients presenting with non-ST-segment elevation ACS. The SYNERGY Library has been designed as a coordinated series of investigations with simultaneous data acquisition on the same cohort of approximately 500 SYNERGY patients at 60 centers in North America. Specifically, electrocardiograms, coronary arteriograms, inflammatory markers, coagulation studies, and genetic samples will be collected and processed at core laboratory facilities, and the results will be stored in a central repository. This novel strategy for substudy investigation is unprecedented in cardiovascular clinical trials. The goal is to gain significant understanding about this patient population, discover new principles of pathophysiology, identify novel pharmacologic targets, and streamline further drug development. It is hoped that the SYNERGY Library will serve as a model for future substudy design to maximize academic insight within the framework of a large-scale, multicenter trial.

Angina, Unstable↗

PubMed2004

Acute Catheterization and Urgent Intervention Triage strategY (ACUITY) trial: study design and rationale.

BACKGROUND: Patients with acute coronary syndromes (ACS; unstable angina and non-ST-segment elevation myocardial infarction) are at significant risk for death and myocardial infarction. Early angiography followed by revascularization is considered the treatment of choice for moderate- to high-risk patients with ACS. However, despite the integration of newer therapies including stents, glycoprotein IIb/IIIa inhibitors, and thienopyridines, the rate of adverse ischemic events still remains unacceptably high, and the intensive pharmacologic regimens used to stabilize the disrupted atherosclerotic plaque and support angioplasty and surgical revascularization procedures elicit a high rate of bleeding complications. Pilot trials suggest that the thrombin-specific anticoagulant bivalirudin may improve clinical outcomes in ACS. STUDY DESIGN: In the Acute Catheterization and Urgent Intervention Triage strategY (ACUITY) trial, 13,800 patients with moderate- to high-risk ACS are being prospectively randomly assigned at up to 600 centers to unfractionated heparin or enoxaparin + IIb/IIIa inhibition, versus bivalirudin + IIb/IIIa inhibition, versus bivalirudin + provisional IIb/IIIa inhibition. All patients undergo cardiac catheterization within 72 hours, followed by percutaneous or surgical revascularization when appropriate. In a second random assignment, patients assigned to receive IIb/IIIa inhibitors are subrandomized to upstream drug initiation, versus IIb/IIIa inhibitor administration during angioplasty only. The primary study end point is the composite of death, myocardial infarction, unplanned revascularization for ischemia, and major bleeding at 30 days. Clinical follow-up will continue for 1 year. CONCLUSIONS: The ACUITY trial is the largest study yet performed in patients with ACS undergoing an invasive strategy. In addition to evaluating the utility of bivalirudin in ACS, this study will also provide important guidance regarding the necessity for and timing of IIb/IIIa inhibitor administration.

Angina, Unstable↗

PubMed2004

Polymer-based paclitaxel-eluting stents in percutaneous coronary intervention: a review of the TAXUS trials.

Drug-eluting stents have altered the practice of interventional cardiology by dramatically reducing the risk of angiographic and clinical restenosis following percutaneous coronary intervention. Based on extensive preclinical study and clinical trial data, the polymer-based, slow rate-release paclitaxel-eluting TAXUS stent has recently received Food and Drug Administration approval for sale in the United States. In the current article, we review the available data from the TAXUS trials that have demonstrated that implantation of the slow rate-release TAXUS stent is safe and, in terms of restenosis, markedly superior to bare metal stenting for the treatment of de novo lesions <28 mm in length in arteries 2.5-3.75 mm in diameter. Additional trials in the TAXUS program are currently examining the role of slow and moderate rate-release polymer-based, paclitaxel-eluting stents in a broader range of clinical settings and lesion subsets.

Angioplasty, Balloon, Coronary↗

PubMed2004

Impact of symptomatic peripheral arterial disease on 1-year mortality in patients undergoing percutaneous coronary interventions.

PURPOSE: To determine the impact of symptomatic peripheral arterial disease (PAD) on clinical outcomes in patients treated with percutaneous coronary interventions (PCI). METHODS AND RESULTS: Symptomatic PAD was identified in 1969 (18.9%) of 10440 consecutive patients undergoing PCI. Patients with PAD were older, more frequently female, and had smaller body surface area and more atherosclerotic risk factors, chronic renal insufficiency, and heart failure. Patients with PAD had lower rates of procedural success (94.2% versus 96.2%, p<0.0001) and higher rates of in-hospital complications, including all-cause mortality (2.1% versus 1.1%, p=0.0002), cardiac death (1.5% versus 0.7%, p=0.0009), urgent coronary artery bypass grafting (1.9% versus 1.2%, p=0.01), recurrent ischemia (5.6% versus 2.8%, p<0.0001), re-PCI to the target lesion (2.4% versus 1.1%, p<0.0001), stroke (0.6% versus 0.3%, p=0.0344), transient ischemic attack (0.4% versus 0.1%, p=0.01), femoral hematoma (10.3% versus 8.5%, p=0.01), retroperitoneal hematoma (0.8% versus 0.3%, p=0.009), limb ischemia (3.0% versus 0.7%, p<0.0001), gastrointestinal bleeding (1.9% versus 0.9%, p<0.0001), and blood transfusion (10.1% versus 5.2%, p<0.0001). At 1-year follow-up, patients with PAD had a higher mortality rate (13.6% versus 5.2%, p<0.0001), a higher rate of myocardial infarction (8.3% versus 6.5%, p=0.008), and also more target lesion (21.2% versus 19.8%, p=0.02) or target vessel revascularization (24.6% versus 21.2%, p=0.002). By multivariate analysis, PAD was an independent predictor of 1-year mortality (odds ratio 1.71, 95% confidence interval 1.42 to 2.07, p<0.0001). CONCLUSIONS: Nearly a fifth of patients undergoing PCI have symptomatic PAD. The presence of PAD is associated with lower rates of procedural success, higher rates of in-hospital and 1-year adverse events, and is independently associated with increased 1-year mortality.

Adult↗

PubMed2003

Comparison of the angiographic outcomes after beta versus gamma vascular brachytherapy for treatment of in-stent restenosis.

This study was designed to compare the angiographic outcomes of beta versus gamma vascular brachytherapy (VBT). We reviewed the angiographic results of 636 lesions (212 that underwent beta and 212 that underwent gamma VBT, and 212 that received placebo) with native coronary in-stent restenosis matched for lesion length, vessel size, preprocedure minimum lumen diameter (MLD), and time to angiographic follow-up in the various randomized clinical trials and studies. Baseline lesion complexity was similar in these 3 groups. Final MLD was smaller in the beta VBT group than in the gamma VBT or placebo group. At follow-up, beta and gamma VBT significantly reduced both angiographic restenosis (34.4% for beta VBT, 26.4% for gamma VBT, and 50.9% in the placebo group; p <0.0001) and recurrent lesion length (9.2 mm for beta VBT, 8.4 mm for gamma VBT, and 15.5 mm placebo, p <0.0001) compared with placebo. Gamma VBT was associated with a greater reduction in restenosis outside the stent than beta VBT. By multivariable analysis, independent angiographic predictors of treated segment restenosis included beta or gamma VBT, lesion length, and vessel size. In matched lesions, beta and gamma VBT achieved similar reductions in treated segment restenosis and recurrent lesion length compared with placebo.

Adult↗

PubMed2003

Prognostic significance of transient no-reflow during primary percutaneous coronary intervention for ST-elevation acute myocardial infarction.

We found that of 1,192 patients who underwent primary percutaneous coronary intervention and who had final Thrombolysis In Myocardial Infarction grade 3 flow at the conclusion of the procedure, transient no-reflow occurred in 16 patients (1.3%). Compared with patients without transient no-reflow during the procedure, those with transient no-reflow had higher in-hospital (2% vs 13%, p=0.04) and 6-month mortality (3% vs 31%, adjusted odds ratio 5.4, 95% confidence interval 1.01 to 29.0, p=0.0001).

Angioplasty, Balloon↗

PubMed2003

Increased CK-MB release is a "trade-off" for optimal stent implantation: an intravascular ultrasound study.

OBJECTIVES: We sought to determine the impact of aggressive stent expansion on creatine kinase-MB isoenzyme (CK-MB) release and clinical restenosis. BACKGROUND: Elevation of CK-MB after percutaneous coronary interventions has been associated with late mortality. METHODS: We identified 989 consecutive patients who underwent intravascular ultrasound-guided stenting of 1,015 coronary lesions. Patients were divided into three groups according to stent expansion, defined as the ratio of final lumen over the reference lumen cross-sectional areas: Group 1 (ratio <70%, n = 117 patients with 126 lesions); Group 2 (ratio 70% to 100%, n = 551 patients with 562 lesions); Group 3 (ratio >100%, n = 321 patients with 327 lesions). RESULTS: The peak CK-MB values increased significantly with increasing stent expansion: CK-MB = 3 to 5x normal occurred 16%, 18%, and 25% in Groups 1, 2, and 3, respectively, p = 0.02; CK-MB >5 times normal occurred 9%, 13%, and 16% respectively, p = 0.02. Conversely, at one year follow-up there was a stepwise decrease in target lesion revascularization (11% vs. 19% and 17%, respectively, p = 0.04) and major adverse cardiac events with increasing stent expansion. In addition, there was a trend toward lower mortality in Group 3 (9% vs. 4.4% vs. 4.0%, p = 0.07). CONCLUSIONS: Intravascular ultrasound-guided stent overexpansion (final lumen greater than reference lumen cross-sectional area) is accompanied by a higher periprocedural CK-MB release but a lower target lesion revascularization and a trend toward lower mortality at one year. Increased periprocedural CK-MB release appears as a trade-off for optimal stent implantation and lower clinical restenosis.

Cineangiography↗

PubMed2003

Prospective, randomized evaluation of thrombectomy prior to percutaneous intervention in diseased saphenous vein grafts and thrombus-containing coronary arteries.

OBJECTIVES: We sought to determine whether routine thrombectomy prior to stent implantation in diseased saphenous vein grafts (SVGs) and thrombus-containing native coronary arteries would reduce peri-procedural myonecrosis and subsequently enhance event-free survival. BACKGROUND: Percutaneous coronary intervention in diseased SVGs and thrombotic native coronary arteries is complicated by a high rate of peri-procedural myocardial infarction (MI). Thrombectomy prior to intervention may enhance the safety of intervention and improve early and late outcomes in these high-risk patients. METHODS: At 60 centers in the U.S. and Canada, 797 patients with 839 diseased SVGs or thrombus-containing native coronary arteries were prospectively randomized to stent implantation with versus without prior thrombectomy with the X-SIZER device (ev3, Plymouth, Minnesota). RESULTS: Peri-procedural MI occurred in 15.8% of patients assigned to the X-SIZER device compared with 16.6% of control patients (p = 0.77), although the rate of large MI (pre-specified as the development of new pathologic Q waves or creatine phosphokinase-MB isoenzyme elevation >8 x upper limits of normal) was reduced with X-SIZER device use from 9.6% to 5.5% (multivariate risk ratio 0.35 [95% confidence interval 0.18 to 0.66], p = 0.002). Major adverse cardiac events (cardiac death, MI, or repeat target vessel revascularization) occurred in 16.8% of X-SIZER patients versus 17.1% of control patients at 30 days (p = 0.92), and in 31.3% of X-SIZER patients versus 28.2% of control patients at 1 year (p = 0.35). CONCLUSIONS: Thrombectomy with the X-SIZER device prior to stent implantation in high-risk diseased SVGs and thrombus-containing native coronary arteries may reduce the extent, but not the occurrence, of myonecrosis. Early and late event-free survival, however, were not improved by routine thrombectomy with this device.

Adult↗

PubMed2003

Acute and long-term outcomes of cutting balloon angioplasty followed by gamma brachytherapy for in-stent restenosis.

In-stent restenosis lesions were divided into 2 groups according to the use of cutting balloon (n = 76) or conventional balloon angioplasty (n = 407) before gamma-brachytherapy. Cutting balloon angioplasty, compared with conventional balloon angioplasty, in patients undergoing gamma-brachytherapy for in-stent restenosis is associated with less requirement for new stents (11% vs 22%, p = 0.02) but similar target vessel revascularization (35.1% vs 29.8%, p = 0.4) at follow-up.

Aged↗

PubMed2003

Impact of renal insufficiency in patients undergoing primary angioplasty for acute myocardial infarction.

BACKGROUND: The prognostic importance of renal insufficiency (RI) in patients undergoing primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) has not been well characterized. METHODS AND RESULTS: PCI was performed in 2082 AMI patients without shock presenting within 12 hours of symptom onset in a prospective, multicenter randomized trial. RI was defined as a calculated (Cockroft-Gault) creatinine clearance (CrCl) < or =60 mL/min. RI at baseline was present in 18% of patients. Compared with patients without RI, patients with RI were older and were more likely to be female; to have hypertension, peripheral vascular disease, or cerebrovascular disease; and to present in heart failure. Mortality was markedly increased in patients with versus without baseline RI both at 30 days (7.5% versus 0.8%, P<0.0001) and at 1 year (12.7% versus 2.4%, P<0.0001). Mortality rates increased incrementally for every 10-mL/min decrease in baseline CrCl. By multivariate analysis, reduced baseline CrCl was a powerful independent predictor of 30-day mortality (hazard ratio, 5.77; P<0.0001) and remained associated with reduced survival at 1 year (hazard ratio, 1.98; P=0.08). Hemorrhagic complications and transfusion requirements were also increased more than 2-fold in patients with RI, as were severe restenosis (diameter stenosis > or =70%; 20.6% versus 11.8%, P=0.024) and infarct artery reocclusion (14.7% versus 7.3%, P=0.02). CONCLUSIONS: Baseline RI in patients with AMI undergoing primary PCI is associated with a markedly increased risk of mortality, as well as bleeding and restenosis. Novel approaches are needed to improve the otherwise poor prognosis of patients with RI and AMI.

Abciximab↗

PubMed2003

Clinical and angiographic correlates and outcomes of suboptimal coronary flow inpatients with acute myocardial infarction undergoing primary percutaneous coronary intervention.

OBJECTIVES: The purpose of this study was to determine the clinical and angiographic correlates and outcomes of patients with suboptimal coronary flow after primary percutaneous coronary interventions (PCI). BACKGROUND: The clinical and angiographic correlates and outcomes of Thrombolysis in Myocardial Infarction (TIMI) < or =2 flow in patients treated with primary PCI are not known. METHODS: We evaluated 3,362 patients with ST elevation myocardial infarction enrolled in various Primary Angioplasty in Myocardial Infarction trials, who underwent primary PCI. RESULTS: Post-procedural final TIMI < or =2 flow occurred in 232 (6.9%) patients. Multivariate analysis identified age > or =70 years (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1 to 2.2), diabetes (OR 1.9; 95% CI, 1.3 to 2.7), symptom onset to emergency room presentation (OR 1.1; 95% CI, 1.1 to 1.2); initial TIMI < or =1 flow (OR 3.2; 95% CI, 1.9 to 5.5), and left ventricular ejection fraction <50% (OR 1.7; 95% CI, 1.2 to 2.4) as independent correlates of final TIMI < or =2 flow. In-hospital (composite of reinfarction, ischemic target vessel revascularization, or death, as well as these events individually) and one-year (reinfarction and/or death) events occurred more frequently in patients with TIMI < or =2 flow. The Cox proportional hazards model identified TIMI < or =2 flow to be independently associated with one-year mortality (hazard ratio 3.8, 95% CI, 2.5 to 5.7). CONCLUSIONS: Final TIMI < or =2 flow, although uncommon after primary PCI, was strongly associated with hospital and one-year adverse events. The clustering of final TIMI < or =2 flow in high-risk groups may partially explain the poor prognosis of these patients. Awareness of these risk factors may be useful to clinicians to triage and treat patients undergoing primary PCI.

Aged↗

PubMed2003

Optimal final lumen area and predictors of target lesion revascularization after stent implantation in small coronary arteries.

Despite similar early clinical events, patients who undergo treatment of small vessels are at an increased risk for target lesion revascularization (TLR) after coronary artery stenting. We sought to determine predictors of TLR after stent implantation in small coronary arteries. We identified 423 consecutive patients who underwent intravascular ultrasound (IVUS)-guided small vessel stenting procedures in 465 coronary lesions with an angiographic reference vessel diameter of <2.75 mm. Patients were divided into 2 groups based on a final IVUS lumen area of < or =6.0 mm2 (n=345 lesions, group I) and >6.0 mm2 (n=115, group II). Baseline patient characteristics and in-hospital outcomes were similar between the 2 groups, except for a higher rate of restenotic lesions in group I and bifurcation lesions in group II. Group I had higher TLR rates at 1 year compared with group II patients (39% vs 26%, p = 0.02). The TLR rate appeared to decrease with greater stent expansion, especially at >90% of the reference vessel area, as assessed by IVUS. By multivariate analysis, an IVUS final stent area of < or =6 mm2, diabetes, absence of prior myocardial infarction, and history of intervention were independent predictors of 1-year TLR in this population. Final stent area of >6.0 mm2 and greater stent expansion were associated with a decrease in TLR. Therefore, there does not appear to be any "downside" to aggressive stent implantation strategies in small vessels. In contrast, IVUS allows maximization of final lumen dimensions to minimize clinical restenosis.

Aged↗

PubMed2003

Usefulness of the angiographic pattern of in-stent restenosis in predicting the success of gamma vascular brachytherapy.

The prognostic role of the angiographic pattern of in-stent restenosis after gamma vascular brachytherapy was assessed from a pooled data set of 4 clinical trials comprising 295 irradiated patients with matched baseline and follow-up angiograms. The binary angiographic restenosis rate increased with worsening in-stent restenosis patterns; however, target lesion revascularization and major adverse cardiac event rates increased for focal, diffuse, and proliferative patterns of in-stent restenosis but not for total occlusions.

Aged↗