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David O Williams

Publications and source records attributed to David O Williams.

At least 37 records · Page 2Linked to original sources
PubMed2005

Temporal variation in inhospital mortality with percutaneous coronary intervention: a report from the National Heart, Lung and Blood Institute Dynamic Registry.

BACKGROUND: Cardiovascular morbidity and mortality display a distinct time dependence also known as circadian variation. Whether such time dependence extends to the risk of procedural-related mortality after percutaneous coronary intervention (PCI) is presently unknown. METHODS: Inhospital mortality was analyzed in 6,347 patients with PCI start times from 8:00 am to 6:59 pm ("usual" workday). The sample was divided into 3 evenly populated groups (morning start 8:00-10:59 AM, midday start 11:00 AM-1:59 PM, afternoon start 2:00-6:59 PM). The association between procedural start time and mortality was assessed using multivariable analysis including a propensity score accounting for factors associated with procedural start time. RESULTS: There was a significant, nonlinear relationship between procedural-related mortality and start time (P = .03). Afternoon start patients were at higher adjusted risk of mortality compared with midday start patients (OR 2.03, 95% CI 1.07-3.83, P = .03 ). Morning start patients were also at higher risk compared with midday start patients although the association was not statistically significant (OR 1.73, 95% CI 0.89-3.39, P = .11). CONCLUSIONS: There is a significant time-dependent variation in the risk of inhospital PCI-related mortality during usual working hours. The highest risk period, taking into account numerous factors that confound this association, is the latter part of the workday. A second period of apparent greater risk occurs during the early part of the workday and is consistent with our present understanding of circadian variation in cardiovascular disease processes.

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PubMed2005

Safety and efficacy of drug-eluting stents.

This review characterizes the relative effectiveness and safety of drug-eluting stents (DES) compared to bare metal stents. The data evaluated will include clinical and angiographic outcomes from randomized clinical trials as well as observational databases and registries including RESEARCH, e-Cypher, and DYNAMIC, which typically include a much broader spectrum of patients. In addition, specific patient subsets, including those patients with multivessel coronary disease, will be evaluated.

Angioplasty, Balloon, Coronary↗
PubMed2004

Hyperbaric oxygen solution infused into the anterior interventricular vein at reperfusion reduces infarct size in swine.

This study was designed to test the hypothesis that raising myocardial O2 via diffusion of a hyperbaric oxygen solution (AO) administered through the anterior interventricular vein (AIV) will reduce infarct size by reducing reperfusion injury associated with reduced neutrophil activation. In three pilot open-chest swine experiments, myocardial tissue Po2 was monitored using an oxygen probe during coronary occlusion (Occl) and reperfusion (Rep). One control experiment had no AIV infusion; a second control received arterial blood drawn from the femoral artery infused into the AIV during Rep. In a third open-chest experiment, AO mixed with arterial blood was infused through the AIV at Rep. In controls, tissue Po2 in the risk region (RR) rose early in Rep and then fell to Occl levels, whereas in AO-treated animals, myocardial Po2 remained above baseline. The following three groups of five swine then underwent 60 min of left anterior descending coronary artery Occl and Rep: 1) arterial blood infused at Rep as controls (Con), 2) AO infused beginning 30 min after Rep (AO 30 min), and 3) AO infused immediately at Rep (AO 0 min). There were no differences among the three groups in hemodynamics or myocardial blood flow during baseline (BL) or Occl or in RR size. However, endocardial blood flow was significantly higher in RR during Rep in AO 0 min vs. control and AO 30 min (P=0.01). Both infarct size (IS) as %heart and IS as %RR were lower in AO 0 min compared with Con and AO 30 min (P <0.01 for both), and myeloperoxidase values were lower for epicardial (P <0.001), midmyocardial (P=0.03), and endocardial (P <0.001) layers in AO 0 min. AO infused into the AIV immediately at Rep diffuses into the RR and reduces IS by reducing Rep injury associated with neutrophil activation.

Animals↗
PubMed2003

Sirolimus-eluting stents versus standard stents in patients with stenosis in a native coronary artery.

BACKGROUND: Preliminary reports of studies involving simple coronary lesions indicate that a sirolimus-eluting stent significantly reduces the risk of restenosis after percutaneous coronary revascularization. METHODS: We conducted a randomized, double-blind trial comparing a sirolimus-eluting stent with a standard stent in 1058 patients at 53 centers in the United States who had a newly diagnosed lesion in a native coronary artery. The coronary disease in these patients was complex because of the frequent presence of diabetes (in 26 percent of patients), the high percentage of patients with longer lesions (mean, 14.4 mm), and small vessels (mean, 2.80 mm). The primary end point was failure of the target vessel (a composite of death from cardiac causes, myocardial infarction, and repeated percutaneous or surgical revascularization of the target vessel) within 270 days. RESULTS: The rate of failure of the target vessel was reduced from 21.0 percent with a standard stent to 8.6 percent with a sirolimus-eluting stent (P<0.001)--a reduction that was driven largely by a decrease in the frequency of the need for revascularization of the target lesion (16.6 percent in the standard-stent group vs. 4.1 percent in the sirolimus-stent group, P<0.001). The frequency of neointimal hyperplasia within the stent was also decreased in the group that received sirolimus-eluting stents, as assessed by both angiography and intravascular ultrasonography. Subgroup analyses revealed a reduction in the rates of angiographic restenosis and target-lesion revascularization in all subgroups examined. CONCLUSIONS: In this randomized clinical trial involving patients with complex coronary lesions, the use of a sirolimus-eluting stent had a consistent treatment effect, reducing the rates of restenosis and associated clinical events in all subgroups analyzed.

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PubMed2003

Ethnic differences in the presentation, treatment strategy, and outcomes of percutaneous coronary intervention (a report from the National Heart, Lung, and Blood Institute Dynamic Registry).

Information about the impact of race/ethnicity on adverse outcomes after percutaneous coronary intervention (PCI) in the modern era is limited. Using consecutive patients from the National Heart, Lung, and Blood Institute Dynamic Registry, this study investigated differences in clinical presentation, treatment strategy, and acute and long-term outcomes in 3,669 white, 446 black, 301 Hispanic, and 201 Asian patients who underwent PCI. All comparisons were made to whites. Blacks were more likely than whites to be younger, women, and to present with a higher prevalence of cardiovascular risk factors (hypertension, diabetes, and smoking). Hispanics tended to be younger, hypertensive, diabetic, and to be undergoing their first cardiovascular procedure. Asians were, on average, younger, men, and presented more often with hypertension and diabetes than whites. Although the rate of stent implantation was significantly lower in blacks compared with whites (63% vs 74%, p <0.001), angiographic and procedural success rates were high (> or =95%) and did not differ by race/ethnicity. In-hospital mortality (0.2% vs 1.7%, p <0.05) and death/myocardial infarction (MI)/coronary artery bypass grafting (CABG) (3.1% vs 5.5%, p <0.05) were lower in blacks. All other in-hospital complications were similar to whites. At 1 year, there were no statistical differences in cumulative adverse event rates by ethnicity; however by 2 years there was a modestly higher mortality rate (adjusted RR 1.87; 95% confidence interval 1.15 to 3.04) and adverse event rate (death/MI, death/MI/CABG) among black patients. Thus, although differences in patient demographics, clinical presentation, angiographic characteristics and treatment strategies did not impact the incidence of acute and 1-year adverse outcomes of non-whites, there appears to be a significant reduction in event-free survival among blacks by 2 years.

Age Distribution↗
PubMed2003

Comparison of in-hospital and one-year outcomes in patients with left ventricular ejection fractions or=50% having percutaneous coronary revascularization.

Outcome studies of percutaneous coronary intervention (PCI) with conventional balloon angioplasty have established increased in-hospital and 1-year mortality in patients with left ventricular (LV) dysfunction compared with others. It is unclear whether recent PCI practice innovations, including stents and adjunctive pharmacotherapy, have made PCI safer and more effective in patients with LV dysfunction. We evaluated the influence of LV ejection fraction (EF) indexes on in-hospital and 1-year outcomes in 1,458 patients within the National Heart, Lung, and Blood Institute-sponsored Dynamic Registry. Patients (n = 300) with acute myocardial infarction were excluded. The remaining 1,158 patients were subdivided into 3 categories: group 1, EF or=50% (n = 866). We determined the frequency of individual and composite adverse events (death/myocardial infarction [MI]/coronary artery bypass grafting) at discharge and 1 year. In the Dynamic Registry patients, mean EF in the 3 groups was 32%, 45%, and 62% and in-hospital mortality was 3.0%, 1.6%, and 0.1%, respectively (p <0.001). The composite end point of death/MI was also significant, but other in-hospital adverse events did not differ between groups. The respective mortality rates were 11.0%, 4.5%, and 1.9% (p <0.001) after 1 year. The composite end points of death/MI and death/MI/coronary artery bypass grafting also occurred more frequently in group 1 patients. Thus, significant LV dysfunction was still associated with increased in-hospital and 1-year mortality in patients having contemporary PCI.

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PubMed2003

Modeling and risk prediction in the current era of interventional cardiology: a report from the National Heart, Lung, and Blood Institute Dynamic Registry.

BACKGROUND: Validation of in-hospital mortality models after percutaneous coronary interventions using multicenter data remains limited. METHODS AND RESULTS: This study evaluated whether multivariable mortality models developed during the pre-stent era by New York State, American College of Cardiology (ACC)-National Cardiovascular Data Registry, Northern New England Cooperative Group, Cleveland Clinic Foundation, and the University of Michigan are relevant in patients undergoing percutaneous coronary intervention in the 1997 to 1999 National Heart, Lung, and Blood Institute Dynamic Registry. Of 4448 Dynamic Registry patients, 73% received > or =1 stent and 28% received a IIB/IIIA receptor inhibitor. In-hospital mortality occurred in 64 patients (1.4%). The New York state model predicted mortality in 69 patients (1.5%; 95% confidence bounds [CI], 0.89% to 1.70%); Northern New England predicted mortality in 60 patients (1.3%; 95% CI, 1.0% to 1.7%); and Cleveland Clinic predicted mortality in 76 patients (1.7%; 95% CI, 1.3% to 2.1%). Among high-risk subgroups, with these 3 models, observed and predicted in-hospital mortality rates in general were not different. The other 2 models yielded different results. The University of Michigan predicted fewer deaths (n=47; 1.1%; 95% CI, 0.7% to 1.3%), and the ACC Registry model predicted 603 deaths (13.5%; 95% CI, 12.6% to 14.4%). Using the ACC Registry model, predicted mortality was higher than observed in each subgroup. CONCLUSIONS: Application of 5 mortality risk models developed from different data sets to patients undergoing percutaneous coronary intervention in the Dynamic Registry predicted, in 3 models, mortality rates that were not significantly different than those observed. In both high and low risk subgroups, the University of Michigan slightly underpredicted mortality, and the ACC Registry predicted significantly higher mortality than that observed.

Angioplasty, Balloon, Coronary↗
PubMed2003

Impact of age on procedural and 1-year outcome in percutaneous transluminal coronary angioplasty: a report from the NHLBI Dynamic Registry.

BACKGROUND: Older age has been associated with adverse outcomes in patients undergoing percutaneous coronary intervention (PCI). As PCI technology evolves and the US population becomes proportionally older, assessment of PCI in older age groups is essential. METHODS: From the National Heart, Lung, and Blood Institute Dynamic Registry, 4620 PCI-treated patients (1997 to 1999) were studied. Differences in clinical presentation, treatment strategy, and inhospital and 1-year outcomes were compared between patient age groups: younger (<65 years, n = 2537); older (65 to 79 years, n = 1776); and elderly (> or =80 years, n = 307). RESULTS: Older and elderly patients had more cardiac and comorbid noncardiac conditions and more extensive and complex arteriosclerosis, including stenoses in bypass grafts. Stent use was similar as age increased (72% vs 73% vs 73%), as was the use of IIb/IIIa receptor antagonists (29% vs 26% vs 28%). Rates of successful treatment of all attempted lesions were 93%, 92%, and 89%, respectively. Adjusted relative risks of inhospital death (1.0 vs 2.91 vs 3.64) and myocardial infarction (1.0 vs 1.35 vs 2.57) increased by age group, as did 1-year mortality rates (1.0 vs 1.87 vs 3.02). However, the relative magnitude of excess mortality rates at 1 year was comparable to that observed by age in the US general population. Age was not associated with 1-year risk of myocardial infarction or coronary artery bypass grafting. CONCLUSIONS: Although new technologies may allow for treatment of complex disease in older and elderly patients with comorbid disease, the increased procedural risk remains substantial in these patients. After PCI, the long-term relative risk of death is similar to that expected among persons of similar ages in the general population.

Age Factors↗
PubMed2003

Validation of R wave voltage endomyocardial mapping to assess myocardial fibrosis: comparison with thallium and dobutamine echocardiography in a swine model.

The first aim of this study was to validate R wave voltage values measured with a catheter-based three-dimensional mapping system (NOGA, Biosense) against myocardial fibrosis in a swine model of ameroid placement. The second aim was to correlate the UPV maps with thallium uptake and low-dose dobutamine echocardiography. The electromechanical catheter mapping system can be used to guide endomyocardial laser therapy and direct gene delivery to the myocardium. The accuracy of R wave voltage in identifying myocardial fibrosis and its comparison with other imaging technologies against histopathology has not been fully investigated in an animal model. Ameroid constrictors were placed on 24 vessels in 14 swine. Wall motion abnormalities by echocardiography were detected in distribution of the constrictors at 22 +/- 10 days. Animals underwent rest and delayed thallium imaging, low-dose dobutamine echocardiography, and R wave voltage mapping. Animals were sacrificed, hearts were removed, 4-micron slices were stained, and fibrosis was quantified. Five control animals were studied to obtain segment normalization. There was significant agreement between each imaging modality and fibrosis by chi-square analysis. The correlation for segment normalized thallium uptake and segment normalized UPV score versus fibrosis were both significant (P < 0.001) with an r2 value of 0.362 vs. thallium, and r2 = 0.445 vs. UPV. The correlation was improved using log of UPV vs. fibrosis (r = 0.532). These results help validate R wave voltage mapping as an imaging technique to identify myocardial fibrosis.

Animals↗
PubMed2002

Comparison of in-hospital and one-year outcomes in patients with and without diabetes mellitus undergoing percutaneous catheter intervention (from the National Heart, Lung, and Blood Institute Dynamic Registry).

Extrapolation of improvements in percutaneous coronary intervention (PCI) and outcomes to patients with diabetes has not been systematically examined in clinical practice. Two waves of consecutive patients (n = 4,629) who underwent PCI from July 1997 to June 1999 enrolled in the National Heart, Lung, and Blood Institute Dynamic Registry comprise the study population. There were 1,058 patients with treated diabetes and 3,571 patients without clinically evident diabetes. As a group, patients with diabetes tended to have more clinical, angiographic, and procedural risk factors. Although crude in-hospital mortality rates were higher in patients with diabetes (diabetics 2.3%, nondiabetics 1.3%; p = 0.02), the adjusted risk of in-hospital death (odds ratio 1.46, 95% confidence interval [CI] 0.80 to 2.66) was not significantly different. At 1 year, patients with diabetes had a significantly higher adjusted risk of mortality (risk ratio [RR] 1.80, 95% CI 1.35 to 2.41) and need for repeat revascularization (RR 1.40, 95% CI 1.13 to 1.74). There was a significant interaction between stent use and diabetic status with the need for repeat revascularization (adjusted RR in nondiabetics 0.73, 95% CI 0.61 to 0.88; adjusted RR in patients with diabetes 1.20, 95% CI 0.88 to 1.65). Beta blockers at the time of hospital discharge were significantly associated with reduced mortality rates at 1 year in both groups.

Age Factors↗
PubMed2002

Contemporary percutaneous coronary intervention versus balloon angioplasty for multivessel coronary artery disease: a comparison of the National Heart, Lung and Blood Institute Dynamic Registry and the Bypass Angioplasty Revascularization Investigation (BARI) study.

BACKGROUND: This investigation compares the results of contemporary percutaneous coronary intervention (PCI) with standard balloon angioplasty among patients with multivessel coronary disease. Patients having balloon angioplasty in the Bypass Angioplasty Revascularization Investigation (BARI) and those within the Dynamic Registry meeting BARI eligibility criteria were studied. METHODS AND RESULTS: Clinical features and in-hospital and 1-year outcomes of 857 BARI-eligible patients in the Dynamic Registry (contemporary PCI) were compared with the 904 randomized patients who underwent percutaneous transluminal coronary angioplasty in BARI. Compared with BARI patients, Registry patients had fewer lesions attempted (1.53 versus 2.56, P=0.001), more frequent single-vessel PCI (76% versus 33%, P<0.001), greater use of intracoronary stents (76% versus 1%, P<0.001), and GP IIb/IIIa receptor antagonist (24% versus 0%, P<0.001). Angiographic success was achieved more often among Registry patients (91% versus 72%, P<0.001), whereas abrupt closure (1.5% versus 9.5%, P<0.001) and in-hospital coronary artery bypass graft (CABG) (1.9% versus 10.2%, P<0.001) and myocardial infarction (0.8% versus 2.1%, P=0.025) were less common. No differences were observed in either in-hospital or 1-year death, but 1-year death/myocardial infarction was lower in the Registry. Registry patients had lower 1-year rates of subsequent CABG (8.6% versus 22.7%, P<0.001) and PCI (12.4% versus 22.5%, P<0.001). By multivariate analysis, contemporary PCI was independently associated with reduced risk for in-hospital CABG, 1-year CABG, and 1-year PCI. CONCLUSIONS: Among patients with multivessel disease, contemporary PCI resulted in safer and more durable revascularization. These results support the role of PCI for selected patients with multivessel coronary artery disease.

Angioplasty, Balloon↗
PubMed2002

Relation of percutaneous coronary intervention of complex lesions to clinical outcomes (from the NHLBI Dynamic Registry).

Advances in percutaneous coronary intervention (PCI) have reduced complications but expanded indications. We used the National Heart, Lung, and Blood Insitute Dynamic Registry to determine clinical outcomes up to 1 year after PCI in 2,839 patients with at least 1 treated complex lesion (defined as a lesion showing evidence of thrombus, calcification, bifurcation or ostial location, or chronic occlusion) and 1,790 patients with only simple lesions treated. Complex lesion interventions were associated (p <0.05) with more sustained major dissections, distal embolization, side branch occlusion, and persistent flow reduction. Patients with treated complex lesions had a lower procedural success rate (93.8% vs 97.3%, p <0.001) and increased in-hospital rates (p <0.001) of death (2.0% vs 0.6%), death/myocardial infarction [MI] (5.2% vs 2.4%), or death/MI/coronary artery bypass graft [CABG] surgery (6.5% vs 2.9%). After adjustment for potential confounders, patients treated for multiple complex lesions were more likely to experience the in-hospital combined end points of death/MI (odds ratio 3.22, 95% confidence interval 2.10 to 4.92), or death/MI/CABG (odds ratio 2.55, 95% confidence interval 1.71 to 3.80). At 1 year, patients with treated complex lesions were more likely (p <0.001) to die (6.2% vs 3.7%), suffer death/MI (11.7% vs 7.5%), or death/MI/CABG/repeat PCI (27.2% vs 23.4%). Patients treated for multiple complex lesions were approximately 50% more likely to die or to have major adverse events than with patients only treated for simple lesions. An increased in-hospital adverse clinical event rate was independently noted for thrombotic, bifurcation, and calcified lesions, and bifurcation lesions had worse long-term event rates.

Angioplasty, Balloon, Coronary↗