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Shakespeare and the digital world : redefining scholarship and practice
\"Due to the unique cultural capital of his works, Shakespeare has long been the test subject for new methods and digital advances in arts scholarship. Shakespeare sits at the forefront of the digital humanities - in archiving, teaching, performance and editing - impacting on scholars, theatres and professional organisations alike. The pace at which new technologies have developed is unprecedented (and the pressure to keep up is only growing). This book offers seventeen new essays that assess the opportunities and pitfalls presented by the twenty-first century for the ongoing exploration of Shakespeare. Through contributions from a broad range of scholars and practitioners, including case studies from those working in the field, the collection engages with the impact of the digital revolution on Shakespeare studies. By assessing and mediating this sometimes controversial digital technology, the book is relevant to those interested in the digital humanities as well as to Shakespeare scholars and enthusiasts\"-- Provided by publisher.
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Irbesartan in Patients with Heart Failure and Preserved Ejection Fraction
In a multicenter trial, 4128 patients who had heart failure with a preserved ejection fraction were randomly assigned to receive irbesartan or placebo and were followed for a mean of 49.5 months. There were no significant differences between the two study groups in the rate of the primary outcome (death or hospitalization for heart failure).
In a multicenter trial, patients who had heart failure with a preserved ejection fraction received irbesartan or placebo and were followed for a mean of 49.5 months. There were no significant differences in death or hospitalization for heart failure.
Approximately half of patients with a diagnosis of heart failure have a normal or near-normal left ventricular ejection fraction.
1
–
5
Such patients differ from those with heart failure and a low left ventricular ejection fraction in a number of important ways: they tend to be older and female, and their condition is more likely to be associated with hypertension than with ischemia. The rates of death and illness among these patients are high and have not declined, as they have in patients with heart failure and a low left ventricular ejection fraction.
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Unfortunately, no pharmacologic therapy has been shown to . . .
Journal Article
Covariate adjusted reanalysis of the I-Preserve trial
BackgroundThe CHARM-Preserved trial suggested that the renin-angiotensin system (RAS) inhibitor candesartan might have been beneficial in heart failure with preserved ejection fraction (HFpEF); however, this hypothesis was not supported by the findings of I-Preserve with irbesartan.AimsTo re-analyse the results of I-Preserve, adjusting for imbalances in baseline variables that may have influenced the trial outcomes.MethodsCox proportional hazards models with covariate adjustment for baseline variables, including age, sex, medical history, physiological and laboratory variables.ResultsIn I-Preserve, 763 (37.0%) participants in the placebo group and 742 (35.9%) in the irbesartan group experienced the primary composite outcome (death from any cause or hospitalization for heart failure, myocardial infarction, unstable angina, arrhythmia, or stroke). The prespecified analysis of this outcome, stratifying for the use of ACEi at baseline, gave a hazard ratio (HR) of 0.95 (95% confidence interval, 0.86–1.05); p = 0.35. Adjusting the effect of treatment for key prognostic baseline variables, gave a HR of 0.89 (0.80–0.99); p = 0.033. Similar findings were observed for the composite of cardiovascular death or HF hospitalization.ConclusionAdjusting for imbalances in baseline variables that influence outcomes (or the response to therapy or both) can improve the power around the estimate of the effect of treatment and may alter its statistical significance. Along with the CHARM-Preserved results, these findings suggest that angiotensin-receptor blockers may have a modest effect in HFpEF.
Journal Article
Uric acid level and allopurinol use as risk markers of mortality and morbidity in systolic heart failure
Previous studies have not extensively examined the association of hyperuricemia and adverse outcomes in systolic heart failure (HF) in relation to xanthine oxidase inhibitor therapy.
The Prospective Randomized Amlodipine Survival Evaluation study included New York Heart Association class IIIB or IV patients with left ventricular ejection fraction <30%. For analysis, the population was divided into uric acid quartiles among nonallopurinol users (2.2-7.1, >7.1-8.6, >8.6-10.4, >10.4 mg/dL) and those using allopurinol. Multivariate Cox regression modeling was performed to identify predictors of mortality. Uric acid quartile and allopurinol groups were referenced to the lowest uric acid quartile.
A total of 1,152 patients were included. In general, patients in the allopurinol group and in the highest uric acid quartile had indicators of more severe HF, including worse renal function and greater proportion of New York Heart Association class IV patients, and greater diuretic use. The allopurinol group and highest uric acid quartile had the highest total mortality (41.7 and 42.4 per 100 person-years, respectively) and combined morbidity/mortality (45.6 and 51.0 per 100 person-years, respectively). Allopurinol use and highest uric acid quartile were independently associated with mortality (hazard ratio [HR] 1.65, 95% CI 1.22-2.23,
P = .001 and HR 1.35, 95% CI 1.07-1.72,
P = .01, respectively) and combined morbidity/mortality (uric acid quartile 4 vs 1: HR 1.32, 95% CI 1.06-1.66,
P = .02; allopurinol use: HR 1.48, 95% CI 1.11-1.99,
P = .008).
Elevated uric acid level was independently associated with mortality in patients with severe systolic HF, even when accounting for allopurinol use.
Journal Article
Valsartan reduces the incidence of atrial fibrillation in patients with heart failure: Results from the Valsartan Heart Failure Trial (Val-HeFT)
Atrial fibrillation (AF) in heart failure (HF) is generally considered a negative prognostic factor. Recent studies indicate that the incidence of AF might be decreased by renin angiotensin aldosterone system inhibitors. The identification of a treatment to prevent its occurrence is likely to improve patients outcome. The aims of these subanalyses of Val-HeFT were to assess (
a) the effects of valsartan in the prevention of AF, (
b) the independent predictors of this event, and (
c) the prognostic role of AF occurrence.
The occurrence of AF was evaluated based on adverse event reports in the patients with HF enrolled in Val-HeFT. Patients were randomized to valsartan or placebo on top of their prescribed treatments for HF. During the mean 23 months of follow-up, AF was reported in 287/4395 patients (6.53%) in sinus rhythm at baseline, of whom 113/2205 (5.12%) were allocated to valsartan and 174/2190 (7.95%) to placebo (
P = .0002). Multivariable analysis showed that brain natriuretic peptide (BNP) levels at baseline above the median value (HR 2.28, 95% CI 1.75-2.98), age over 70 years (HR 1.51, 95% CI 1.17-1.95), male sex (HR 1.53, 95% CI 1.07-2.18), and the valsartan treatment (HR 0.63, 95% CI 0.49-0.81) were independently associated with AF occurrence. Cox multivariable regression analysis showed that occurrence of AF was independently associated with a worse prognosis, with the adjusted hazard risks for all-cause mortality and combined mortality/morbidity of 1.40 (95% CI 1.16-1.58) and 1.38 (95% CI 1.12-1.70), respectively.
The results of the present study demonstrate that (
a) adding valsartan to prescribed therapy for HF significantly reduces the incidence of AF by 37%; (
b) BNP level and advanced age were the strongest independent predictors for AF occurrence; and (
c) AF occurrence further worsens the outcome in patients with HF.
Journal Article
A randomized controlled trial evaluating the safety and efficacy of cardiac contractility modulation in advanced heart failure
Cardiac contractility modulation (CCM) delivers nonexcitatory electrical signals to the heart during the absolute refractory period intended to improve contraction.
We tested CCM in 428 New York Heart Association class III or IV, narrow QRS heart failure patients with ejection fraction (EF) ≤35% randomized to optimal medical therapy (OMT) plus CCM (n = 215) versus OMT alone (n = 213). Efficacy was assessed by ventilatory anaerobic threshold (VAT), primary end point, peak Vo2 (pVo2), and Minnesota Living with Heart Failure Questionnaire (MLWFQ) at 6 months. The primary safety end point was a test of noninferiority between groups at 12 months for the composite of all-cause mortality and hospitalizations (12.5% allowable delta).
The groups were comparable for age (58 ± 13 vs 59 ± 12 years), EF (26% ± 7% vs 26% ± 7%), pVo2 (14.7 ± 2.9 vs 14.8 ± 3.2 mL kg−1 min−1), and other characteristics. While VAT did not improve at 6 months, CCM significantly improved pVo2 and MLWHFQ (by 0.65 mL kg−1 min−1 [P = .024] and −9.7 points [P < .0001], respectively) over OMT. Forty-eight percent of OMT and 52% of CCM patients experienced a safety end point, which satisfied the noniferiority criterion (P = .03). Post hoc, hypothesis-generating analysis identified a subgroup (characterized by baseline EF ≥25% and New York Heart Association class III symptoms) in which all parameters were improved by CCM.
In the overall target population, CCM did not improve VAT (the primary end point) but did improve pVo2 and MLWHFQ. Cardiac contractility modulation did not have an adverse affect on hospitalizations or mortality within the prespecified boundaries. Further study is required to clarify the role of CCM as a treatment for medically refractory heart failure.
Journal Article
Developing and validating models to predict sudden death and pump failure death in patients with heart failure and preserved ejection fraction
BackgroundSudden death (SD) and pump failure death (PFD) are leading modes of death in heart failure and preserved ejection fraction (HFpEF). Risk stratification for mode-specific death may aid in patient enrichment for new device trials in HFpEF.MethodsModels were derived in 4116 patients in the Irbesartan in Heart Failure with Preserved Ejection Fraction trial (I-Preserve), using competing risks regression analysis. A series of models were built in a stepwise manner, and were validated in the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM)-Preserved and Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trials.ResultsThe clinical model for SD included older age, men, lower LVEF, higher heart rate, history of diabetes or myocardial infarction, and HF hospitalization within previous 6 months, all of which were associated with a higher SD risk. The clinical model predicting PFD included older age, men, lower LVEF or diastolic blood pressure, higher heart rate, and history of diabetes or atrial fibrillation, all for a higher PFD risk, and dyslipidaemia for a lower risk of PFD. In each model, the observed and predicted incidences were similar in each risk subgroup, suggesting good calibration. Model discrimination was good for SD and excellent for PFD with Harrell’s C of 0.71 (95% CI 0.68–0.75) and 0.78 (95% CI 0.75–0.82), respectively. Both models were robust in external validation. Adding ECG and biochemical parameters, model performance improved little in the derivation cohort but decreased in validation. Including NT-proBNP substantially increased discrimination of the SD model, and simplified the PFD model with marginal increase in discrimination.ConclusionsThe clinical models can predict risks for SD and PFD separately with good discrimination and calibration in HFpEF and are robust in external validation. Adding NT-proBNP further improved model performance. These models may help to identify high-risk individuals for device intervention in future trials.Clinical trial registrationI-Preserve: ClinicalTrials.gov NCT00095238; TOPCAT: ClinicalTrials.gov NCT00094302; CHARM-Preserved: ClinicalTrials.gov NCT00634712.Graphic abstract
Journal Article
Combinatorial Pharmacogenetic Interactions of Bucindolol and β1, α2C Adrenergic Receptor Polymorphisms
Pharmacogenetics involves complex interactions of gene products affecting pharmacodynamics and pharmacokinetics, but there is little information on the interaction of multiple genetic modifiers of drug response. Bucindolol is a β-blocker/sympatholytic agent whose efficacy is modulated by polymorphisms in the primary target (β(1) adrenergic receptor [AR] Arg389 Gly on cardiac myocytes) and a secondary target modifier (α(2C) AR Ins [wild-type (Wt)] 322-325 deletion [Del] on cardiac adrenergic neurons). The major allele homozygotes and minor allele carriers of each polymorphism are respectively associated with efficacy enhancement and loss, creating the possibility for genotype combination interactions that can be measured by clinical trial methodology.
In a 1,040 patient substudy of a bucindolol vs. placebo heart failure clinical trial, we tested the hypothesis that combinations of β(1)389 and α(2C)322-325 polymorphisms are additive for both efficacy enhancement and loss. Additionally, norepinephrine (NE) affinity for β(1)389 AR variants was measured in human explanted left ventricles.
The combination of β(1)389 Arg+α(2C)322-325 Wt major allele homozygotes (47% of the trial population) was non-additive for efficacy enhancement across six clinical endpoints, with an average efficacy increase of 1.70-fold vs. 2.32-fold in β(1)389 Arg homozygotes+α(2C)322-325 Del minor allele carriers. In contrast, the minor allele carrier combination (13% subset) exhibited additive efficacy loss. These disparate effects are likely due to the higher proportion (42% vs. 8.7%, P = 0.009) of high-affinity NE binding sites in β(1)389 Arg vs. Gly ARs, which converts α(2C)Del minor allele-associated NE lowering from a therapeutic liability to a benefit.
On combination, the two sets of AR polymorphisms 1) influenced bucindolol efficacy seemingly unpredictably but consistent with their pharmacologic interactions, and 2) identified subpopulations with enhanced (β(1)389 Arg homozygotes), intermediate (β(1)389 Gly carriers+α(2C)322-325 Wt homozygotes), and no (β(1)389 Gly carriers+α(2C)322-325 Del carriers) efficacy.
Journal Article
Association Between Bilirubin and Mode of Death in Severe Systolic Heart Failure
The bilirubin level has been associated with worse outcomes, but it has not been studied as a predictor for the mode of death in patients with systolic heart failure. The Prospective Randomized Amlodipine Evaluation Study (PRAISE) cohort (including New York Heart Association class IIIB-IV patients with left ventricular ejection fraction <30%, n = 1,135) was analyzed, divided by bilirubin level: ≤0.6 mg/dl, group 1; >0.6 to 1.2 mg/dl, group 2; and >1.2 mg/dl, group 3. Multivariate Cox proportional hazards models were used to determine the association of bilirubin with the risk of sudden or pump failure death. Total bilirubin was entered as a base 2 log-transformed variable (log2 bilirubin), indicating doubling of the bilirubin level corresponding to each increase in variable value. The higher bilirubin groups had a lower ejection fraction (range 19% to 21%), sodium (range 138 to 139 mmol/L), and systolic blood pressure (range 111 to 120 mm Hg), a greater heart rate (range 79 to 81 beats/min), and greater diuretic dosages (range 86 to 110 furosemide-equivalent total daily dose in mg). The overall survival rates declined with increasing bilirubin (24.3, 31.3, and 44.3 deaths per 100 person-years, respectively, for groups 1, 2, and 3). Although a positive relation was seen between log2 bilirubin and both pump failure risk and sudden death risk, the relation in multivariate modeling was significant only for pump failure mortality (hazard ratio 1.47, 95% confidence interval 1.19 to 1.82, p = 0.0004), not for sudden death mortality (hazard ratio 1.21, 95% confidence interval 0.98 to 1.49, p = 0.08). In conclusion, an increasing bilirubin level was significantly associated with the risk of pump failure death but not for sudden death in patients with severe systolic heart failure.
Journal Article
Use of endpoint adjudication to improve the quality and validity of endpoint assessment for medical device development and post marketing evaluation: Rationale and best practices. A report from the cardiac safety research consortium
This white paper provides a summary of presentations, discussions and conclusions of a Thinktank entitled “The Role of Endpoint Adjudication in Medical Device Clinical Trials”. The think tank was cosponsored by the Cardiac Safety Research Committee, MDEpiNet and the US Food and Drug Administration (FDA) and was convened at the FDA's White Oak headquarters on March 11, 2016. Attention was focused on tailoring best practices for evaluation of endpoints in medical device clinical trials, practical issues in endpoint adjudication of therapeutic, diagnostic, biomarker and drug-device combinations, and the role of adjudication in regulatory and reimbursement issues throughout the device lifecycle. Attendees included representatives from medical device companies, the FDA, Centers for Medicare and Medicaid Services (CMS), end point adjudication specialist groups, clinical research organizations, and active, academically based adjudicators. The manuscript presents recommendations from the think tank regarding (1) rationale for when adjudication is appropriate, (2) best practices establishment and operation of a medical device adjudication committee and (3) the role of endpoint adjudication for post market evaluation in the emerging era of real world evidence.
Journal Article