[Show abstract][Hide abstract] ABSTRACT: Recognition of learning curves in medical skill acquisition has enhanced patient safety through improved training techniques. Clinical trials research has not been similarly scrutinised. The VALsartan In Acute myocardial iNfarcTion, a large multinational, pragmatic, randomised, double-blind, multicentre trial, was retrospectively evaluated for evidence of research conduct consistent with a performance "learning curve".
Records provided protocol departure (deviations/violations) and documentation query data. For each site, analysis included patient order (eg, first, second), recruitment rate and first enrollment relative to study start date.
Computerised data from a trial coordinated by an academic research organisation collaborating with 10 academic and 2 commercial research organisations and an industry sponsor. Interventions 931 sites enrolled 14,703 patients. Departures were restricted to the first year. Exclusions included patient's death or loss to follow-up within 12 months and subjects enrolled 80th or higher at a site. Departures were assessed for variance with higher patient rank, more frequent recruitment and later start date.
12,367 patients at 931 sites were analysed. Departures were more common for patients enrolled earlier at a site (p<0.0001). For example, compared with the 30th patient, the first had 47% more departures. Departures were also more common with slower enrollment and site start closer to the trial start date (p<0.0001). Similar patterns existed for queries.
Research performance improved during the VALsartan In Acute myocardial iNfarcTion consistent with a "learning curve". Although effects were not related to a change in outcome (mortality), learning curves in clinical research may have important safety, ethical, research quality and economic implications for trial conduct.
Quality and Safety in Health Care 10/2010; 19(5):405-10. DOI:10.1136/qshc.2008.028605 · 2.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: IMS: Recurrent myocardial infarction (MI) is common after a first MI and is associated with increased morbidity and mortality. Predictors and prognosis of a recurrent MI with contemporary management are not well known. METHODS AND RESULTS: We assessed the predictors and prognostic impact of a first recurrent MI in 10,599 patients with left ventricular dysfunction, heart failure, or both following a first MI from the Valsartan in Acute Myocardial Infarction Trial (VALIANT) cohort. During a median follow-up of 27.4 months, 861 patients (9.6%) had a recurrent MI. The median time to recurrence was 136 days (quartiles 35-361 days), with a declining rate of recurrent MI within the first 3 months. The strongest predictors of recurrent MI were reduced estimated glomerular filtration rate, unstable angina, diabetes, and age. Mortality was markedly elevated (20.5%) within the first 7 days of a recurrent MI. Patients who survived 7 days after a recurrent MI continued to be at increased risk of death compared with patients without a recurrent MI and the risk of death remained elevated more than two-fold a year after the recurrent MI (adjusted hazards ratio 2.4, 95% confidence interval 1.7-3.2). One-year mortality for the entire VALIANT cohort was 10.3%, whereas 38.3% of the patients were dead 1 year after recurrent MI. Early reinfarctions (within 1 month) was associated with significantly higher 30-day mortality than later reinfarctions. CONCLUSION: Even in the context of contemporary treatment, a recurrent MI confers a significantly increased risk of death in patients following a high-risk first MI. Strategies aimed at reducing recurrent MI will thus likely prolong survival in post-MI survivors.
European Journal of Heart Failure 10/2010; 13(2):148-53. DOI:10.1093/eurjhf/hfq194 · 6.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Patients with left ventricular (LV) systolic dysfunction after myocardial infarction (MI) are at particularly high risk for recurrent adverse outcomes. The magnitude of the decrease in risk associated with smoking cessation after MI has not been well described in patients with LV dysfunction after MI. We aimed to quantify the risk decrease associated with smoking cessation in subjects with LV dysfunction after MI. The Survival and Ventricular Enlargement (SAVE) trial randomized 2,231 subjects with LV dysfunction 3 to 16 days after MI. Smoking status was assessed at randomization and at regular intervals during a median follow-up of 42 months. Propensity score-adjusted Cox proportional hazard models were used to quantify the decrease in risk of all-cause mortality, death or recurrent MI, and death or heart failure (HF) hospitalization associated with smoking cessation. In baseline smokers who survived to 6 months without interval events, smoking cessation at 6-month follow-up was associated with a significantly lower adjusted risk of all-cause mortality (hazard ratio [HR] 0.57, 95% confidence interval [CI] 0.31 to 0.91), death or recurrent MI (HR 0.68, 95% CI 0.47 to 0.99), and death or HF hospitalization (HR 0.65, 95% CI 0.46 to 0.92). In conclusion, in patients with LV dysfunction after MI, smoking cessation is associated with a 40% lower hazard of all-cause mortality and a 30% lower hazard of death or recurrent MI or death or HF hospitalization. These findings indicate that smoking cessation is beneficial after high-risk MI and highlight the importance of smoking cessation as a therapeutic target in patients with LV dysfunction after MI.
The American journal of cardiology 10/2010; 106(7):911-6. DOI:10.1016/j.amjcard.2010.05.021 · 3.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In trials of chronic disease therapy, each patient may experience several nonfatal illnesses and death. "Composite" outcome measures combine information from these different components of disease burden. Most common is the binary distinction between patients undergoing one or more events and those undergoing no events. We compare this approach with a composite score that preserves information on the number and severity of events.
The binary composite measure and composite score were derived for each patient in a trial of cardiovascular therapy. All nonfatal events contributed to the composite score according to their severity: recurrent myocardial infarction (weight 0.5), congestive heart failure that required the use of open-label angiotensin-converting enzyme (ACE) inhibitors (weight 0.2), and hospitalization to treat congestive heart failure (weight 0.5).
In the example data set, the composite score required a 10% larger sample size to achieve the same power as the binary measure. However, the composite score suggested that the treatment impacted on the first nonfatal event and mortality only.
The composite score provides a more informative measure of disease burden and may avoid overestimating the evidence supporting a treatment effect when that evidence is largely from less severe early events.
[Show abstract][Hide abstract] ABSTRACT: Non–placebo-controlled trials of erythropoiesis-stimulating agents (ESAs) comparing lower and higher hemoglobin targets in patients with chronic kidney disease indicate that targeting of a lower hemoglobin range may avoid ESA-associated risks. However, target-based strategies are confounded by each patient's individual hematopoietic response.
We assessed the relationship among the initial hemoglobin response to darbepoetin alfa after two weight-based doses, the hemoglobin level achieved after 4 weeks, the subsequent darbepoetin alfa dose, and outcomes in 1872 patients with chronic kidney disease and type 2 diabetes mellitus who were not receiving dialysis. We defined a poor initial response to darbepoetin alfa (which occurred in 471 patients) as the lowest quartile of percent change in hemoglobin level (<2%) after the first two standardized doses of the drug.
Patients who had a poor initial response to darbepoetin alfa had a lower average hemoglobin level at 12 weeks and during follow-up than did patients with a better hemoglobin response (a change in hemoglobin level ranging from 2 to 15% or more) (P<0.001 for both comparisons), despite receiving higher doses of darbepoetin alfa (median dose, 232 μg vs. 167 μg; P<0.001). Patients with a poor response, as compared with those with a better response, had higher rates of the composite cardiovascular end point (adjusted hazard ratio, 1.31; 95% confidence interval [CI], 1.09 to 1.59) or death (adjusted hazard ratio, 1.41; 95% CI, 1.12 to 1.78).
A poor initial hematopoietic response to darbepoetin alfa was associated with an increased subsequent risk of death or cardiovascular events as doses were escalated to meet target hemoglobin levels. Although the mechanism of this differential effect is not known, these findings raise concern about current target-based strategies for treating anemia in patients with chronic kidney disease. (Funded by Amgen; ClinicalTrials.gov number, NCT00093015.)
New England Journal of Medicine 09/2010; 363(12):1146-55. DOI:10.1056/NEJMoa1005109 · 55.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cardiac resynchronization therapy (CRT) plus implantation of an implantable cardioverter defibrillator (ICD) reduced the risk of death or heart failure event in patients with mildly symptomatic heart failure, left ventricular dysfunction, and wide QRS complex compared with an ICD only. We assessed echocardiographic changes in patients enrolled in the MADIT-CRT trial (Multicenter Automatic Defibrillator Implantation Trial: Cardiac Resynchronization Therapy) to evaluate whether the improvement in outcomes with CRT plus an ICD was associated with favorable alterations in cardiac size and function.
A total of 1,820 patients were randomly assigned to CRT plus an ICD or to an ICD only in a 3:2 ratio. Echocardiographic studies were obtained at baseline and 12 months later in 1,372 patients. We compared changes in cardiac size and performance between treatment groups and assessed the relationship between these changes over the first year, as well as subsequent outcomes. Compared with the ICD-only group, the CRT-plus-ICD group had greater improvement in left ventricular end-diastolic volume index (-26.2 versus -7.4 mL/m(2)), left ventricular end-systolic volume index (-28.7 versus -9.1 mL/m(2)), left ventricular ejection fraction (11% versus 3%), left atrial volume index (-11.9 versus -4.7 mL/m(2)), and right ventricular fractional area change (8% versus 5%; P<0.001 for all). Improvement in end-diastolic volume at 1 year was predictive of subsequent death or heart failure, with adjustment for baseline covariates and treatment group; each 10% decrease in end-diastolic volume was associated with a 40% reduction in risk (P<0.001).
CRT resulted in significant improvement in cardiac size and performance compared with an ICD-only strategy in patients with mildly symptomatic heart failure. Improvement in these measures accounted for the outcomes benefit. Clinical Trial Registration Information- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180271.
[Show abstract][Hide abstract] ABSTRACT: Randomized clinical trials have suggested that treatment of anaemia with erythropoiesis-stimulating agents (ESAs) in patients with cancer or chronic kidney disease may increase cardiovascular risk. We therefore examined the effect of treating anaemia with an ESA in patients with heart failure in a meta-analysis of randomized clinical trials, including the recently reported TREAT study.
We performed a systematic review and meta-analysis of all prospective, randomized, controlled studies of ESAs enrolling patients with heart failure and reporting data on mortality or non-fatal heart failure events. Of 10 trials initially identified by our search strategy, we pooled data from 9 placebo-controlled studies enrolling a total of 2039 patients, of whom 1023 (50.2%) were allocated to ESA treatment. The pooled risk ratio for ESA treatment relative to placebo was 1.03 [95% confidence interval (CI): 0.89-1.21, P = 0.68] for overall mortality and 0.95 (95% CI: 0.82-1.10, P = 0.46) for worsening heart failure.
The use of ESAs to manage anaemia in patients with heart failure was associated with a neutral effect on both mortality and non-fatal heart failure events. Definitive assessment of the balance of risk and benefit in this population awaits the completion of a randomized clinical trial adequately powered to assess clinical outcomes.
European Journal of Heart Failure 09/2010; 12(9):936-42. DOI:10.1093/eurjhf/hfq094 · 6.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The frequency of sudden unexpected death is highest in the early post-myocardial infarction (MI) period; nevertheless, 2 recent trials showed no improvement in mortality with early placement of an implantable cardioverter-defibrillator after MI.
To better understand the pathophysiological events that lead to sudden death after MI, we assessed autopsy records in a series of cases classified as sudden death events in patients from the VALsartan In Acute myocardial infarctioN Trial (VALIANT). Autopsy records were available in 398 cases (14% of deaths). We determined that 105 patients had clinical circumstances consistent with sudden death. On the basis of the autopsy findings, we assessed the probable cause of sudden death and evaluated how these causes varied with time after MI. Of 105 deaths considered sudden on clinical grounds, autopsy suggested the following causes: 3 index MIs in the first 7 days (2.9%); 28 recurrent MIs (26.6%); 13 cardiac ruptures (12.4%); 4 pump failures (3.8%); 2 other cardiovascular causes (stroke or pulmonary embolism; 1.9%); and 1 noncardiovascular cause (1%). Fifty-four cases (51.4%) had no acute specific autopsy evidence other than the index MI and were thus presumed arrhythmic. The percentage of sudden death due to recurrent MI or rupture was highest in the first month after the index MI. By contrast, after 3 months, the percentage of presumed arrhythmic death was higher than recurrent MI or rupture (chi(2)=23.3, P<0.0001).
Recurrent MI or cardiac rupture accounts for a high proportion of sudden death in the early period after acute MI, whereas arrhythmic death may be more likely subsequently. These findings may help explain the lack of benefit of early implantable cardioverter-defibrillator therapy.
[Show abstract][Hide abstract] ABSTRACT: Myocardial rupture is a relatively rare and usually fatal complication of myocardial infarction (MI). Early recognition of patients at greatest risk of myocardial rupture provides an opportunity for early intervention.
VALIANT was a double-blind, randomized, controlled trial comparing valsartan, captopril, and their combination in high-risk patients post-MI. Myocardial rupture was identified by autopsy (available in 138/589 patients dying within 30 days of index MI), echocardiography, direct surgical visualization, or presence of hemopericardium. An independent clinical end points committee reviewed medical records for all deaths or suspected nonfatal cardiovascular events.
Rupture was identified in 45 (0.31%) patients enrolled in VALIANT, occurring 9.8 +/- 6.0 days after the qualifying MI. Rupture accounted for 7.6% (45/589) of all deaths occurring in the first 30 days of follow-up and 24% (33/138) of deaths in which autopsies were obtained. Compared with survivors, rupture was associated with increased age, hypertension, increased Killip class, lower estimated glomerular filtration rate, and Q wave MI, and inversely related to beta-blocker and diuretic use. Compared with patients who died of other causes within 30 days, patients with myocardial rupture were more likely to have had an inferior MI, Q wave MI, or hypertension; to have used oral anticoagulants; or to have received thrombolytic therapy.
Although rare, myocardial rupture accounted for nearly one fourth of all deaths within the first 30 days after high-risk MI, suggesting an estimated incidence of approximately 1% within the first 30 days. A number of clinical characteristics may identify post-MI patients at higher risk of myocardial rupture.
American heart journal 07/2010; 160(1):145-51. DOI:10.1016/j.ahj.2010.02.037 · 4.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Trialists have an ethical and financial responsibility to plan and conduct clinical trials in a manner that will maximize the scientific knowledge gained from the trial. However, the amount of scientific information generated by randomized clinical trials in cardiovascular medicine is highly variable. Generation of trial databases and/or biobanks originating in large randomized clinical trials has successfully increased the knowledge obtained from those trials. At the 10th Cardiovascular Trialist Workshop, possibilities and pitfalls in designing and accessing clinical trial databases were discussed by a group of trialists. This review focuses on the arguments for conducting posttrial database studies and presents examples of studies in which posttrial knowledge generation has been substantial. Possible strategies to ensure successful trial database or biobank generation are discussed, in particular with respect to collaboration with the trial sponsor and to analytic pitfalls. The advantages of creating screening databases in conjunction with a given clinical trial are described; and finally, the potential for posttrial database studies to become a platform for training young scientists is outlined.
American heart journal 06/2010; 159(6):937-43. DOI:10.1016/j.ahj.2010.03.002 · 4.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It is unknown whether there is an interaction between aspirin and angiotensin receptor blockers on outcomes in patients with heart failure (HF).
The efficacy and safety of candesartan vs. placebo was assessed in 7599 patients with symptomatic HF and reduced or preserved left ventricular ejection fraction enrolled in the CHARM programme according to baseline aspirin use. Patients were randomized to candesartan or matching placebo and were followed for a median of 38 months. Aspirin was used in 4246 (55.9%) of patients at baseline. When compared with placebo, candesartan use was associated with lower event rates for cardiovascular (CV) death or HF hospitalization (primary outcome) in both the aspirin group (28 vs. 31.9%, HR 0.81, 95% CI 0.72-0.90) and non-aspirin group (33 vs. 38%, HR 0.81, 95% CI 0.72-0.91). Baseline aspirin use did not modify the effectiveness of candesartan in reducing the risk of CV death or HF hospitalization in CHARM overall (P = 0.64) or in the CHARM individual trials. In addition, there was no significant interaction between aspirin therapy and candesartan in terms of discontinuation of study drug due to adverse reactions (P = 0.72).
There appears to be no significant modification of the benefit of candesartan on CV mortality and morbidity outcomes or safety by concomitant use of aspirin in patients with chronic HF.
European Journal of Heart Failure 04/2010; 12(7):738-45. DOI:10.1093/eurjhf/hfq065 · 6.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Heart failure (HF) and chronic obstructive pulmonary disease are common partners. Bronchodilators are associated with adverse cardiovascular outcomes in patients with pulmonary disease. The outcome of patients with HF prescribed bronchodilators is poorly defined.
The Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) programme randomized 7599 patients with symptomatic HF to receive candesartan or placebo. The relative risk conveyed by bronchodilator therapy was examined using a multivariable Cox proportional hazards model. The prevalence of bronchodilator therapy was similar in patients with reduced and preserved systolic function (respectively, 8.7 vs. 9.2%, P = 0.46). Beta-blocker utilization was markedly lower in patients receiving bronchodilators compared with those without (overall 31.9 vs. 57.6%, P < 0.0001). Bronchodilator use was associated with increased all-cause mortality [HR 1.26 (1.09-1.45), P = 0.0015], cardiovascular death [HR 1.21 (1.03-1.42), P = 0.0216], HF hospitalization [HR 1.49 (1.29-1.72), P < 0.0001], and major adverse cardiovascular events [HR 1.32 (1.17-1.76), P < 0.0001]. The adverse outcomes were consistent in patients with reduced and preserved systolic function. No significant interaction was observed between bronchodilators and beta-blockade with respect to outcomes.
Bronchodilator use is a powerful independent predictor of worsening HF and increased mortality in a broad spectrum of patients with HF. Whether this relates to a toxic effect of bronchodilators, underlying pulmonary disease, or both is unclear and warrants further investigation.
European Journal of Heart Failure 03/2010; 12(6):557-65. DOI:10.1093/eurjhf/hfq040 · 6.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Patients with atrial fibrillation usually are elderly and may have cognitive dysfunction. These patients may receive less effective oral anticoagulation, resulting in more vascular events and bleeding.
In an analysis of cognitive function associated with the time in therapeutic range (TTR) in the Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events, 2510 patients (mean age, 71+/-9.5 years) from 27 countries completed the Mini-Mental State Examination (MMSE). Of these patients, 171 (6.8%) had an MMSE score <24, suggesting dementia, and 194 (7.7%) had intermediate scores of 24 to 25. Low MMSE scores were correlated with a low TTR. Even mild cognitive impairment was associated with a TTR below the median (<65%). Patients with an MMSE score <26 had more vascular events (6.7% versus 3.6% per 100 patient-years; P=0.002) and more bleeding (9.6% versus 7% per 100 patient-years; P=0.04). After controlling for TTR, the MMSE no longer conferred increased risk, suggesting that if improved anticoagulation was provided, vascular events and bleeding would be reduced. Other independent factors associated with a TTR <65% were region of the world, recent initiation of vitamin K antagonist, type of anticoagulant, and concurrent use of amiodarone or insulin. After adjustment for these factors, lower MMSE scores still predicted a reduced TTR.
Cognitive dysfunction is common in elderly patients with atrial fibrillation and is related to less effective anticoagulation and more vascular events. The MMSE identifies patients with atrial fibrillation in whom extra efforts are needed to maintain effective anticoagulation and improve outcomes. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00243178.
[Show abstract][Hide abstract] ABSTRACT: Mechanical dyssynchrony is considered an independent predictor for adverse cardiovascular outcomes in patients with heart failure. However, its importance as a risk factor after myocardial infarction is not well defined.
We examined the influence of mechanical dyssynchrony on outcome in patients with left ventricular dysfunction, heart failure, or both after myocardial infarction who were enrolled in the Valsartan in Acute Myocardial Infarction (VALIANT) echocardiography study. B-mode speckle tracking with velocity vector imaging was used to assess ventricular synchrony in 381 patients who had image quality sufficient for analysis. Time to regional peak velocity and time to strain rate were measured among 12 left ventricular segments from the apical 4- and 2- chamber views, and the SDs between all 12 segments were used as a measure of dyssynchrony. The relationships between the SD of time to regional peak velocity and strain rate and clinical outcome of death or heart failure were assessed. In a multivariate Cox model adjusted for clinical and echocardiographic variables, the SD of time to peak velocity (hazard ratio per 10 ms, 1.10; 95% confidence interval, 1.02 to 1.18; P=0.010) and the SD of time to strain rate (hazard ratio per 10 ms, 1.16; 95% confidence interval, 1.06 to 1.27; P=0.001) were independent predictors of death or heart failure.
Left ventricular dyssynchrony is independently associated with increased risk of death or heart failure after myocardial infarction, suggesting that contractile pattern may play a role in post-myocardial infarction prognosis.
[Show abstract][Hide abstract] ABSTRACT: Higher levels of serum alkaline phosphatase (AlkP) are associated with excess mortality in dialysis patients, but whether AlkP is associated with adverse outcomes among people without kidney failure is unknown.
We first analyzed the association between AlkP and cardiovascular outcomes among 4115 participants with a previous myocardial infarction (the Cholesterol And Recurrent Events [CARE] study). Results were validated by analyzing the association between AlkP and mortality in an independent sample of 14,716 adults from the general US population (the Third National Health and Nutrition Examination Survey). A graded, independent association was noted between baseline tertile of AlkP and the adjusted hazard ratio of all-cause mortality in CARE participants (P(trend)=0.02). After adjustment for serum phosphate, hepatic enzymes, and other potential confounders, participants with AlkP in the highest tertile had an adjusted hazard ratio of 1.43 (95% confidence interval 1.08 to 1.89) compared with those in the lowest tertile. Multivariable-adjusted associations between higher AlkP and all-cause and cardiovascular mortality were present in the Third National Health and Nutrition Examination Survey (P(trend) across tertiles of AlkP=0.006 and 0.038, respectively). Findings from both CARE and the Third National Health and Nutrition Examination Survey were similar among individuals with and without evidence of kidney disease, defined by estimated glomerular filtration rate <60 mL min(-1) 1.73 m(-2).
We found an independent relation between higher levels of AlkP and adverse outcomes among survivors of myocardial infarction and in a general population sample. The excess risk of death was present in people without evidence of kidney disease and was particularly high among people with higher levels of both AlkP and serum phosphate.
[Show abstract][Hide abstract] ABSTRACT: Although many patients with heart failure have incomplete adherence to prescribed medications, predisposing factors remain unclear. This analysis investigates factors associated with adherence, with particular emphasis on age and sex.
A multivariable regression analysis of 7599 heart failure patients from the CHARM trial was done to evaluate factors associated with adherence. Adherence was measured as the proportion of time patients took more than 80% of study medication. The mean age was 66 years (SD 11) and 31.5% (n = 2400) were women. Women were slightly less adherent than men (87.3 vs. 89.8%, P = 0.002), even in adjusted, multivariable models (treatment, P = 0.006; placebo P = 0.004; and overall P < 0.001). However, all-cause mortality was lower in women (21.5%) than in men (25.3%) (adjusted hazard ratio, 0.77; 95% CI, 0.69-0.86; P < 0.001), but patients with a low adherence regardless of sex had a higher mortality. Age, severity of heart failure, number of medications, and smoking status were not associated with adherence.
Women, particularly those <75 years of age, were less likely to be adherent in this large sample of patients with symptomatic heart failure. Understanding factors associated with adherence may provide opportunities for intervention.
European Journal of Heart Failure 11/2009; 11(11):1092-8. DOI:10.1093/eurjhf/hfp142 · 6.53 Impact Factor