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Vic Hasselblad

Publications and source records attributed to Vic Hasselblad.

At least 37 records · Page 2Linked to original sources
PubMed2004

Differential treatment benefit of platelet glycoprotein IIb/IIIa inhibition with percutaneous coronary intervention versus medical therapy for acute coronary syndromes: exploration of methods.

BACKGROUND: Although many believe that platelet glycoprotein IIb/IIIa inhibitors should be used only in acute coronary syndrome patients undergoing percutaneous coronary intervention, supporting data from randomized clinical trials are tenuous. The assumption that these agents are useful only in conjunction with percutaneous coronary intervention is based primarily on inappropriate subgroup analyses performed across the glycoprotein IIb/IIIa inhibitor trials. METHODS AND RESULTS: We describe the problems with these analytical techniques and demonstrate that different approaches to the question can result in opposing answers. CONCLUSIONS: Clinical-practice decisions and practice guidelines should be based on overall trial results and not analyses of post-randomization subgroups.

Acute Disease↗
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

Implications of elevated cardiac troponin T in ambulatory patients with heart failure: a prospective analysis.

BACKGROUND: Elevated concentrations of cardiac troponin T (TnT) have been reported in patients hospitalized for decompensated heart failure (HF). We assessed whether elevated TnT levels are associated with the severity, etiology, and prognosis of HF in stable, ambulatory patients. METHODS: From 1998-1999, we prospectively collected data from 136 ambulatory patients with HF, New York Heart Association functional class II to IV, ejection fraction < or =35%, and no recent unstable angina, myocardial infarction, surgery, or coronary revascularization. Blood was obtained and analyzed by immunoassay for TnT, and patients were followed for 14.0 +/- 4.3 months for death or HF hospitalization (primary end point) and other adverse cardiovascular outcomes. RESULTS: Thirty-three patients (24%) had an elevated TnT level (> or =0.02 ng/mL). Mean TnT concentration did not differ by etiology of HF (0.002 +/- 0.03 ng/mL vs 0.02 +/- 0.04 ng/mL for ischemic and nonischemic etiologies, P =.25). Compared with patients with normal (undetectable) levels of TnT, patients with elevated TnT were significantly older, had worse functional class, and had poorer renal function. Elevated TnT concentrations were associated with increased relative risks (RR) of death or HF hospitalization (RR 2.7, 95% CI 1.7-4.3, P =.001) and death alone (RR 4.2, 95% CI 1.8-9.5, P =.001) during follow-up. Elevated TnT and New York Heart Association class were significant, independent predictors of death or HF hospitalization. Increased age and serum creatinine concentrations were significant independent predictors of death alone. CONCLUSIONS: Nearly one fourth of ambulatory patients with chronic HF have ongoing myocardial necrosis as shown by abnormal TnT values, which are associated with increased mortality and morbidity.

Aged↗
PubMed2003

Meta-analysis of survival with platelet glycoprotein IIb/IIIa antagonists for percutaneous coronary interventions.

We performed a cumulative meta-analysis of available studies to evaluate the effect of intravenous platelet glycoprotein (GP) IIb/IIIa antagonists on survival at 30 days and 6 months after percutaneous coronary intervention (PCI). Compounds that block the GP IIb/IIIa receptor substantially reduce myocardial infarctions (MIs) and repeat revascularization. We included 12 trials, which enrolled 20,186 patients in all, in the analysis. Overall, 30-day mortality was significantly reduced with GP IIb/IIIa inhibition (odds ratio 0.73, 95% confidence interval 0.55 to 0.96, p = 0.024). Although 10 of the 12 trials showed a beneficial effect of GP IIb/IIIa inhibitor treatment on mortality, no individual trial detected a statistically significant mortality benefit. The 30-day mortality benefit became significant at the p <0.05 level with addition of the ADMIRAL trial and was further enhanced by the CADILLAC trial. No significant heterogeneity was detected in the collection of trials. At 6 months, the odds ratio was 0.84 (95% confidence interval 0.69 to 1.03, p = 0.087). This survival benefit amounts to preventing approximately 1 of every 3 deaths that occur within 30 days after PCI, saving 2.8 lives/1,000 patients treated (number needed to treat, 357). Thus, patients who undergo PCI can expect significantly lower 30-day mortality, in addition to known reductions in nonfatal MI and repeat procedures, with GP IIb/IIa inhibition. There also is increasing evidence that mortality reductions are preserved at 6 months.

Angioplasty, Balloon, Coronary↗
PubMed2003

Reduction of myocardial ischemic injury following coronary intervention (the MC-1 to Eliminate Necrosis and Damage trial).

Myocardial ischemic injury complicating acute myocardial infarction (AMI) and coronary revascularization procedures remains an unresolved clinical dilemma. In preclinical studies, treatment with pyridoxal-5'-phosphate monohydrate (MC-1), a vitamin B6 metabolite, has demonstrated cardioprotective effects. Sixty patients scheduled for elective percutaneous coronary intervention (PCI) who had clinically high-risk characteristics for ischemic complications were randomized to treatment with MC-1 or placebo in a 2:1 double-blinded fashion. The primary end point was defined as infarct size as measured by area under the curve creatine kinase MB (CK-MB) enzymes. Secondary end points included periprocedural ischemia as assessed by continuous electrocardiographic monitoring, 30-day major adverse cardiac events, and net clinical safety, which included liver function testing. The primary end point, median periprocedural CK-MB area under the curve, was reduced from 32.9 ng/ml in the placebo group to 18.6 ng/ml with MC-1 treatment (p = 0.038), reflecting a shift in the distribution of CK-MB. By categorical classification, the occurrence of 30-day nonfatal AMI did not differ between groups. There were no deaths, and 30-day composite adverse event rates were similar (17.9% MC-1 vs 15.0% placebo, p = 1.0). There were no significant differences in ischemia parameters per continuous electrocardiographic monitoring, and no safety issues were identified. In this phase II pilot study, treatment of high-risk patients who underwent PCI with MC-1 was associated with a decrease in the total amount of CK-MB released after PCI. These results support the evaluation of MC-1 in pivotal trials of patients at risk for developing myocardial ischemia, infarction, or reperfusion injury.

Aged↗
PubMed2003

Power calculations for large multi-arm placebo-controlled studies of dichotomous outcomes.

Several statistical methods can be used to test for differences in placebo-controlled dichotomous multi-arm studies. These tests include linear and quadratic trends, Dunnett's test, Hochberg's test, and the overall chi-square test. We computed the power of these tests under a wide variety of alternatives. For two arms versus a control, the power was computed exactly. For more than two arms, the power was calculated from 100000 simulations per alternative. Against monotonic alternatives, the linear trend test tended to be superior. Against convex alternatives, the quadratic trend test tended to be superior. Against general alternatives, Dunnett's test, Hochberg's test, and the overall chi-square test were superior and had very similar power curves. The Hochberg test was generally less powerful than Dunnett's test but the difference was offset by its increased power to reject multiple hypotheses. These results remained nearly constant over a wide range of sample sizes, average event rates and average effect sizes.

Abciximab↗
PubMed2003

Tezosentan in patients with acute heart failure and acute coronary syndromes: results of the Randomized Intravenous TeZosentan Study (RITZ-4).

OBJECTIVES: We sought to determine the effect of tezosentan in patients with acute decompensated heart failure (HF) associated with acute coronary syndrome (ACS). BACKGROUND: Tezosentan is a dual endothelin receptor antagonist that has been shown to improve cardiac output, decrease pulmonary capillary wedge pressure, and reduce pulmonary and systemic vascular resistance in initial clinical studies in acute decompensated HF. METHODS: The Randomized Intravenous TeZosentan (RITZ)-4 study was a multicenter, randomized, double-blinded, placebo-controlled study of tezosentan in patients with acute decompensated HF associated with ACS. A total of 193 patients were randomized to receive tezosentan (25 mg/h for 1 h, then 50 mg/h for 23 to 47 h) or placebo. Patients with evidence of acute decompensated HF and ACS were eligible to participate. The primary end point was the composite of death, worsening HF, recurrent ischemia, and recurrent or new myocardial infarction within 72 h. RESULTS: No significant differences were observed between placebo and 50 mg/h tezosentan in the composite primary end point: 24.2% (95% confidence interval [CI] 16.0% to 34.1%) and 28.9% (95% CI 20.1% to 39.0%), respectively (p = 0.5152). Symptomatic hypotension was more frequent in the treatment group. CONCLUSIONS: At the doses studied, tezosentan did not result in a significant improvement in the composite primary clinical end point in the RITZ-4 trial. Tezosentan did not demonstrate pro-ischemic effects in this population. Symptomatic hypotension may have resulted in an increased number of adverse events in the treatment group. Further studies with lower tezosentan doses are warranted.

Acute Disease↗
PubMed2003

Prognostic value of isolated troponin elevation across the spectrum of chest pain syndromes.

The risk of death or recurrent myocardial infarction (MI) in patients with chest pain and baseline isolated troponin elevation is unclear. To determine the early and short-term risk of death or MI associated with isolated troponin elevation across a spectrum of chest pain syndromes, we used baseline creatine kinase (CK)-MB and troponin data from the Platelet IIb/IIIa Antagonism for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network (PARAGON) B troponin substudy, the Global Utilization of Strategies To Open Occluded Coronary Arteries (GUSTO) IIa troponin substudy, and the Chest Pain Evaluation by Creatine Kinase-MB, Myoglobin, and Troponin I (CHECKMATE) study. Patients were grouped into 1 of 4 categories based on marker status (troponin-positive/CK-MB-positive, troponin-positive/CK-MB-negative, troponin-negative/CK-MB-positive, or troponin-negative/CK-MB-negative). The adjusted odds of death or MI occurring at 24 hours and 30 days was assessed by baseline marker status using multivariable logistic regression, with the group negative for both markers used as the reference. Patients who were positive for both markers had the highest odds of the 24-hour and 30-day end point. The adjusted odds of the 30-day end point for patients with isolated troponin elevation were 1.3 (95% confidence interval 0.7 to 2.3) and 4.8 (95% confidence interval 1.4 to 16.0) for high- and low-risk patients, respectively. The risk for 24-hour and 30-day death or MI with isolated positive CK-MB results was lower than with isolated positive troponin results, and it was not significantly greater than if the 2 markers were negative. For patients with high- and low-risk chest pain, baseline troponin elevation without CK-MB elevation was associated with increased risk for early and short-term adverse outcomes. This suggests that these patients should be admitted to the hospital and monitored in either an intensive care or step-down unit.

Aged↗
PubMed2003

Troponin T and quantitative ST-segment depression offer complementary prognostic information in the risk stratification of acute coronary syndrome patients.

OBJECTIVES: Our primary objective was to examine the prognostic relationship between baseline quantitative ST-segment depression (ST) and cardiac troponin T (cTnT) elevation. The secondary objectives were to: 1) examine whether ST provided additional insight into therapeutic efficacy of glycoprotein IIb/IIIa therapy similar to that demonstrated by cTnT; and 2) explore whether the time to evaluation impacted on each marker's relative prognostic utility. BACKGROUND: The relationship between the baseline electrocardiogram (ECG) and cTnT measurements in risk-stratifying patients presenting with acute coronary syndromes (ACS) has not been evaluated comprehensively. METHODS: The study population consisted of 959 patients enrolled in the cTnT substudy of the Platelet IIb/IIIa Antagonism for the Reduction of Acute coronary syndrome events in a Global Organization Network (PARAGON)-B trial. Patients were classified as having no ST (n = 387), 1 mm ST (n = 433), and ST > or =2 mm (n = 139). Forty-percent (n = 381) were classified as cTnT-positive based on a definition of > or =0.1 ng/ml. RESULTS: Six-month death/(re)myocardial infarction rates were 8.4% among cTnT-negative patients with no ST and 26.8% among cTnT-positive patients with ST > or =2 mm. On ECGs done after 6 h of symptom onset, ST > or =2 mm was associated with higher risk compared to its presence on ECGs done earlier (odds ratio [OR] 7.3 vs. 2.1). In contrast, the presence of elevated cTnT within 6 h of symptom was associated with a higher risk of adverse events compared with elevations after 6 h (OR 2.4 vs. 1.5). CONCLUSIONS: Quantitative ST and cTnT status are complementary in assessing risk among ACS patients and both should be employed to determine prognosis and assist in medical decision making.

Acetates↗
PubMed2003

Revascularization in patients with coronary artery disease, left ventricular dysfunction, and viability: a meta-analysis.

BACKGROUND: The effects of viability status and treatment allocation on long-term mortality in patients with left ventricular dysfunction and coronary artery disease have not been determined. Several observational studies with significant limitations have addressed this issue, and a recent meta-analysis has attempted to combine these results to increase statistical power. However, the analysis did not test for an interaction between viability status and treatment type, and included extraneous studies. We provide an alternate meta-analysis of this primary literature, utilizing interaction statistical methodology on relevant data and factoring in multiple limitations. METHODS: We examined papers from this prior meta-analysis examining viable and nonviable patients undergoing surgical or medical therapy. We determined an interaction odds ratio for each study and used an empirical Bayes random-effects model to obtain a combined interaction odds ratio that was tested for statistical significance. We compared our results against an interaction odds ratio we estimated from the primary studies included in the previous meta-analysis. RESULTS: Nine relevant studies with 1244 patients and 172 events were identified that utilized all 4 treatment/viability subsets. The interaction odds ratio was 2.76 (P =.0176, 95% CI 1.19-6.38), 2.5 times lower than our estimated interaction odds ratio of 7.27 for the prior meta-analysis. CONCLUSIONS: We found a markedly reduced but statistically significant interaction between viability status and treatment allocation. However, numerous limitations in the primary studies and the application of meta-analysis along with significant improvements in medical therapies render a randomized controlled trial necessary to reach a definitive conclusion to this critical question.

Coronary Artery Disease↗
PubMed2003

Evaluation of an infrared/radiofrequency equipment-tracking system in a tertiary care hospital.

Optimal management of assets in large hospitals is important to both cost control and patient care. A prospective controlled evaluation was conducted to determine whether an asset-tracking system using combined radiofrequency and infrared signals could increase equipment utilization, increase appropriate charge capture, and decrease personnel time spent looking for equipment. Two wards at Duke University Medical Center were randomly assigned as intervention and control. Beds sequential compression devices (SCDs), and infusion pumps were monitored during a 6-week intervention period, preceded and followed by 6-week control periods. The system's accuracy for detecting equipment, relative to a trained surveyor, was greater than 80%. Accuracy for locating equipment to a specific room was 60-80%. With the system available, we observed increased utilization of infusion pumps but not of beds or SCDs. Nursing staff and system users had positive impressions of the system and its potential. Tracking systems can successfully locate hospital equipment and may improve utilization.

Academic Medical Centers↗
PubMed2003

Effectiveness of disease management programs in depression: a systematic review.

OBJECTIVE: The authors systematically evaluated the published evidence to assess the effectiveness of disease management programs in depression. METHOD: English-language articles on depression were identified through a MEDLINE search for the period from January 1987 to June 2001. Two reviewers evaluated 16,952 published titles, identified 24 depression disease management programs that met explicit inclusion criteria, and extracted data on study characteristics, interventions used, and outcome measures. Pooled effect sizes were calculated by using a random-effects model. RESULTS: Pooled results for disease management program effects on symptoms of depression showed statistically significant improvements (effect size=0.33, N=24). Programs also had statistically significant effects on patients' satisfaction with treatment (effect size=0.51, N=6), patients' compliance with the recommended treatment regimen (effect size=0.36, N=7), and adequacy of prescribed treatment (effect size=0.44, N=11). One program with an explicit screening component showed significant improvement in the rate of detection of depression by primary care physicians (effect size=0.66); two other programs lacking a screening component showed small nonsignificant improvements in the detection rate (effect size=0.18). Disease management programs increased health care utilization (effect size=-0.10, N=8), treatment costs (effect size=-1.03, N=3), and hospitalization (effect size=-0.20, N=2). CONCLUSIONS: Disease management appears to improve the detection and care of patients with depression. Further research is needed to assess the cost-effectiveness of disease management in depression, and consideration should be given to more widespread implementation of these programs.

Chronic Disease↗
PubMed2002

Coronary artery pattern and outcome of arterial switch operation for transposition of the great arteries: a meta-analysis.

BACKGROUND: Prior studies of coronary pattern and outcome after arterial switch operation (ASO) for transposition of the great arteries (TGA) have been hindered by limited statistical power. This meta-analysis assesses the effect of coronary anatomy on post-ASO mortality, both overall and adjusted for time. METHODS AND RESULTS: A literature search revealed 9 independent series that reported post-ASO mortality by coronary pattern in a total of 1942 patients. Odds ratios comparing all-cause mortality in patients with usual versus variant coronary patterns were calculated and combined by use of an empirical Bayesian model. Single coronary patterns, both of which loop around the great vessels, were associated with significant mortality (OR 2.9, 95% CI 1.3 to 6.8), whereas looping patterns that arose from 2 separate ostia were not (OR 1.2, 95% CI 0.8 to 1.9). This latter group includes patients with the most common variant, circumflex from right coronary artery. Patients with an intramural coronary artery had the greatest mortality (OR 6.5, 95% CI 2.9 to 14.2). Overall, patients with any variant coronary pattern had nearly twice the mortality seen in those with the usual pattern (OR 1.7, 95% CI 1.3 to 2.4). Single ostium patterns and intramural coronary arteries remained associated with significant added mortality after adjustment for time-trend effects. CONCLUSIONS: Over the past 2 decades, patients with common coronary variants have undergone ASO without added mortality compared with those with the usual coronary pattern. Those with intramural or single coronary arteries have significant added mortality that has persisted over time.

Coronary Vessel Anomalies↗
PubMed2002

Interventions used in disease management programmes for patients with chronic illness-which ones work? Meta-analysis of published reports.

OBJECTIVE: To systematically evaluate the published evidence regarding the characteristics and effectiveness of disease management programmes. DESIGN: Meta-analysis. DATA SOURCES: Computerised databases for English language articles during 1987-2001. STUDY SELECTION: 102 articles evaluating 118 disease management programmes. MAIN OUTCOME MEASURES: Pooled effect sizes calculated with a random effects model. RESULTS: Patient education was the most commonly used intervention (92/118 programmes), followed by education of healthcare providers (47/118) and provider feedback (32/118). Most programmes (70/118) used more than one intervention. Provider education, feedback, and reminders were associated with significant improvements in provider adherence to guidelines (effect sizes (95% confidence intervals) 0.44 (0.19 to 0.68), 0.61 (0.28 to 0.93), and 0.52 (0.35 to 0.69) respectively) and with significant improvements in patient disease control (effect sizes 0.35 (0.19 to 0.51), 0.17 (0.10 to 0.25), and 0.22 (0.1 to 0.37) respectively). Patient education, reminders, and financial incentives were all associated with improvements in patient disease control (effect sizes 0.24 (0.07 to 0.40), 0.27 (0.17 to 0.36), and 0.40 (0.26 to 0.54) respectively). CONCLUSIONS: All studied interventions were associated with improvements in provider adherence to practice guidelines and disease control. The type and number of interventions varied greatly, and future studies should directly compare different types of intervention to find the most effective.

Chronic Disease↗
PubMed2002

Systematic review and meta-analysis of monotherapy compared with combined androgen blockade for patients with advanced prostate carcinoma.

BACKGROUND: The current systematic review and meta-analysis compared monotherapy and combined androgen blockade in the treatment of men with advanced prostate carcinoma. Outcomes of interest included overall, cancer specific, and progression-free survival; time to treatment failure; adverse events; and quality of life. METHODS: The literature search identified randomized trials comparing monotherapy (orchiectomy and luteinizing hormone-releasing hormone [LHRH] agonists) with combination therapy using orchiectomy or a LHRH agonist plus a nonsteroidal or steroidal antiandrogen. Dual independent review occurred. The meta-analysis used a random effects model. RESULTS: Twenty-one trials compared survival after monotherapy with survival after combined androgen blockade (n = 6871 patients). The meta-analysis found no statistically significant difference in survival at 2 years between patients treated with combined androgen blockade and those treated with monotherapy (20 trials; hazard ratio [HR] = 0.970; 95% confidence interval [95% CI], 0.866-1.087). The authors determined a statistically significant difference in survival at 5 years that favored combined androgen blockade (10 trials; HR = 0.871; 95% CI, 0.805-0.942). For the subgroup of patients with a good prognosis, there was no statistically significant difference in survival. Adverse effects leading to withdrawal from therapy occurred more often with combined androgen blockade. To the authors' knowledge there is little evidence published to date comparing the effects of combined androgen blockade and monotherapy on quality of life, but the single randomized trial that adequately addressed this outcome reported an advantage for monotherapy over combined androgen blockade. CONCLUSIONS: A thorough examination of the usefulness of combined androgen blockade must balance the modest increase in expected survival observed at 5 years against the increased risk of adverse effects and the potential for adversely affecting the patient's overall quality of life.

Androgen Antagonists↗
PubMed2002

Prognostic significance of elevated troponin I after percutaneous coronary intervention.

OBJECTIVES: We sought to assess the incidence and clinical significance of elevated cardiac troponin I (cTnI) after percutaneous coronary intervention (PCI). BACKGROUND: Elevated creatine kinase-MB (CK-MB) is prognostically important after PCI, but the prognostic significance of elevated cTnI after PCI is uncertain. METHODS: In a prospective substudy of the Sibrafiban Versus Aspirin to Yield Maximum Protection From Ischemic Heart Events Post-acute Coronary Syndromes (SYMPHONY) trials, which randomized patients with acute coronary syndromes (ACS) to receive aspirin or sibrafiban, we measured cTnI (positive, > or =1.5 ng/ml) and CK-MB (positive, > or =7 ng/ml) in 481 patients with PCI. Samples were collected immediately before and at 0, 8 and 16 h after PCI and analyzed by a core laboratory. The primary end point was the Kaplan-Meier estimate of death, myocardial infarction or severe, recurrent ischemia at 90 days. RESULTS: Overall, 230 patients (48%) had elevated cTnI after PCI. Such patients underwent PCI sooner and were more likely to have coronary stenting. Elevated cTnI was associated with nonsignificantly higher risks of the primary end point (11.5% vs. 8.7%; p = 0.15) and of death (1.8% vs. 0.4%; p = 0.4) and a significantly higher risk of death or infarction (10.6% vs. 4.2%; p = 0.005). This pattern was more pronounced for patients who became positive only after PCI: primary end point, 20.7% vs. 10.1% for patients who remained negative after PCI (p = 0.05); death, 5.2% vs. 0% (p = 0.02); death or infarction, 18.1% vs. 4.1% (p = 0.007). CONCLUSIONS: Elevated cTnI, often observed after PCI in patients with ACS, is associated with worse 90-day clinical outcomes. This marker, therefore, is a useful prognostic indicator in such patients.

Angina, Unstable↗