Effects of Serelaxin in Patients with Acute Heart Failure

BACKGROUND

Serelaxin is a recombinant form of human relaxin-2, a vasodilator hormone that contributes to cardiovascular and renal adaptations during pregnancy. Previous studies have suggested that treatment with serelaxin may result in relief of symptoms and in better outcomes in patients with acute heart failure.

METHODS

In this multicenter, double-blind, placebo-controlled, event-driven trial, we enrolled patients who were hospitalized for acute heart failure and had dyspnea, vascular congestion on chest radiography, increased plasma concentrations of natriuretic peptides, mild-to-moderate renal insufficiency, and a systolic blood pressure of at least 125 mm Hg, and we randomly assigned them within 16 hours after presentation to receive either a 48-hour intravenous infusion of serelaxin (30 μg per kilogram of body weight per day) or placebo, in addition to standard care. The two primary end points were death from cardiovascular causes at 180 days and worsening heart failure at 5 days.

RESULTS

A total of 6545 patients were included in the intention-to-treat analysis. At day 180, death from cardiovascular causes had occurred in 285 of the 3274 patients (8.7%) in the serelaxin group and in 290 of the 3271 patients (8.9%) in the placebo group (hazard ratio, 0.98; 95% confidence interval [CI], 0.83 to 1.15; P = 0.77). At day 5, worsening heart failure had occurred in 227 patients (6.9%) in the serelaxin group and in 252 (7.7%) in the placebo group (hazard ratio, 0.89; 95% CI, 0.75 to 1.07; P = 0.19). There were no significant differences between the groups in the incidence of death from any cause at 180 days, the incidence of death from cardiovascular causes or rehospitalization for heart failure or renal failure at 180 days, or the length of the index hospital stay. The incidence of adverse events was similar in the two groups.

CONCLUSIONS

In this trial involving patients who were hospitalized for acute heart failure, an infusion of serelaxin did not result in a lower incidence of death from cardiovascular causes at 180 days or worsening heart failure at 5 days than placebo. (Funded by Novartis Pharma; RELAX-AHF-2 ClinicalTrials.gov number, NCT01870778.).

Day vs night: Does time of presentation matter in acute heart failure? A secondary analysis from the RELAX-AHF trial

BACKGROUND

Signs and symptoms of heart failure can occur at any time. Differences between acute heart failure (AHF) patients who present at nighttime vs daytime and their outcomes have not been well studied. Our objective was to determine if there are differences in baseline characteristics and clinical outcomes between AHF patients presenting during daytime vs nighttime hours within an international, clinical trial.

METHODS

This is a post hoc analysis of the RELAX AHF trial, which randomized 1,161 AHF patients to serelaxin vs placebo, both in addition to usual AHF therapy. Prespecified end points of the primary trial were used: dyspnea, 60-day heart failure/renal failure rehospitalization or cardiovascular (CV) death, and 180-day CV death. Both unadjusted and adjusted analyses for outcomes stratified by daytime vs nighttime presentation were performed.

RESULTS

Of the 1,161 RELAX-AHF patients, 775 (66.8%) patients presented during daytime and 386 (33.2%) at nighttime. Baseline characteristics were largely similar, although daytime patients were more likely to be male, have greater baseline body weight, have higher New York Heart Association class, have history of atrial fibrillation, and have more peripheral edema compared with nighttime patients. No differences in dyspnea relief or 60-day outcomes were observed. However, daytime presentation was associated with greater risk for 180-day CV death after adjustment (hazard ratio 2.28, 95% CI 1.34-3.86; c statistic = 0.82, 95% CI 0.78-0.86).

CONCLUSION

In this secondary analysis of the RELAX-AHF trial, baseline characteristics suggest that daytime-presenting patients may have more gradual worsening of chronic HF. Patients with AHF who presented at night had less risk for 180-day CV death, but similar risk for 60-day CV death or rehospitalization and symptom improvement for patients who presented during the daytime.

Serelaxin in addition to standard therapy in acute heart failure: rationale and design of the RELAX-AHF-2 study

Patients admitted for acute heart failure (AHF) experience high rates of in-hospital and post-discharge morbidity and mortality despite current therapies. Serelaxin is recombinant human relaxin-2, a hormone with vasodilatory and end-organ protective effects believed to play a central role in the cardiovascular and renal adaptations of human pregnancy. In the phase 3 RELAX-AHF trial, serelaxin met its primary endpoint of improving dyspnoea through day 5 in patients admitted for AHF. Compared to placebo, serelaxin also reduced worsening heart failure (WHF) by 47% through day 5 and both all-cause and cardiovascular mortality by 37% through day 180. RELAX-AHF-2 ( ClinicalTrials.gov NCT01870778) is designed to confirm serelaxin's effect on these clinical outcomes. RELAX-AHF-2 is a multicentre, randomized, double-blind, placebo-controlled, event-driven, phase 3 trial enrolling ∼6800 patients hospitalized for AHF with dyspnoea, congestion on chest radiograph, increased natriuretic peptide levels, mild-to-moderate renal insufficiency, and systolic blood pressure ≥125 mmHg. Patients are randomized within 16 h of presentation to 48 h intravenous infusions of serelaxin (30 µg/kg/day) or placebo, both in addition to standard of care treatments. The primary objectives are to demonstrate that serelaxin is superior to placebo in reducing: (i) 180 day cardiovascular death, and (ii) occurrence of WHF through day 5. Key secondary endpoints include 180 day all-cause mortality, composite of 180 day combined cardiovascular mortality or heart failure/renal failure rehospitalization, and in-hospital length of stay during index AHF. The results from RELAX-AHF-2 will provide data on the potential beneficial effect of serelaxin on cardiovascular mortality and WHF in selected patients with AHF.

Serelaxin in acute heart failure patients with and without atrial fibrillation: a secondary analysis of the RELAX-AHF trial

BACKGROUND

Atrial fibrillation (AFib) is a common comorbidity in HF and affects patients' outcome. We sought to assess the effects of serelaxin in patients with and without AFib.

METHODS

In a post hoc analysis of the RELAX-AHF trial, we compared the effects of serelaxin on efficacy end points, safety end points and biomarkers in 1161 patients with and without AFib on admission electrocardiogram.

RESULTS

AFib was present in 41.3% of patients. Serelaxin had a similar effect in patients with and without AFib, including dyspnea relief by visual analog scale through day 5 [mean change in area under the curve, 541.11 (33.79, 1048.44), p = 0.0366 in AFib versus 361.80 (-63.30, 786.90), p = 0.0953 in non-AFib, interaction p = 0.5954] and all-cause death through day 180 [HR = 0.42 (0.23, 0.77), p = 0.0051 in AFib versus 0.90 (0.53, 1.52), p = 0.6888 in non-AFib, interaction p = 0.0643]. Serelaxin was similarly safe in the two groups and induced similar reductions in biomarkers of cardiac, renal and hepatic damage. Stroke occurred more frequently in AFib patients (2.8 vs. 0.8%, p = 0.0116) and there was a trend for lower stroke incidence in the serelaxin arm in AFib patients (odds ratios, 0.31, p = 0.0759 versus 3.88, p = 0.2255 in non-AFib, interaction p = 0.0518).

CONCLUSIONS

Serelaxin was similarly safe and efficacious in improving short- and long-term outcomes and inducing organ protection in acute HF patients with and without AFib.

Sex differences in early dyspnea relief between men and women hospitalized for acute heart failure: insights from the RELAX-AHF study

AIMS

Women with heart failure are typically older, and more often have hypertension and a preserved left ventricular ejection fraction as compared with men. We sought to analyze if these sex differences influence the course and outcome of acute heart failure.

METHODS AND RESULTS

We analyzed sex differences in acute heart failure in 1161 patients enrolled in the RELAX-AHF study. The pre-specified study endpoints were used. At baseline, women (436/1161 patients) were older, had a higher left ventricular ejection fraction, a higher rate of hypertension, and were treated differently from men. Early dyspnea improvement (moderate or marked dyspnea improvement measured by Likert scale during the first 24 h) was greater in women. However, dyspnea improvement over the first 5 days (change from baseline in the visual analog scale area under the curve (VAS AUC) to day 5) was similar between men and women. Women reported greater improvements in general wellbeing by Likert, but no such benefits were evident with the VAS score. Multi-variable predictors of moderate or marked dyspnea improvement were female sex (p = 0.0011), lower age (p = 0.0026) and lower diuretic dose (p = 0.0067). The additional efficacy endpoints of RELAX-AHF were similar between men and women and serelaxin was equally effective in men and women.

CONCLUSIONS

Women exhibit better earlier dyspnea relief and improvement in general wellbeing compared with men, even adjusted for age and left ventricular ejection fraction. However, in-hospital and post-discharge clinical outcomes were similar between men and women. This trial is registered at ClinicalTrials.gov, NCT00520806.

Evaluating the Efficacy, Safety, and Tolerability of Serelaxin When Added to Standard Therapy in Asian Patients With Acute Heart Failure: Design and Rationale of RELAX-AHF-ASIA Trial

BACKGROUND

Acute heart failure (AHF), a common and growing health concern worldwide, is associated with high risk of post-discharge rehospitalization and mortality. Existing evidence indicates potential therapeutic benefits of serelaxin in Caucasian AHF patients, but corresponding data in Asians remain scarce. RELAX-AHF-ASIA, a multinational, randomized, double-blind, placebo-controlled, phase III trial, will evaluate the effects of serelaxin on symptom relief and clinical outcomes in Asian AHF patients, with the use of novel assessments.

METHODS AND RESULTS

Patients with AHF, systolic blood pressure ≥125 mm Hg, and mild to moderate renal dysfunction will be randomized within 16 hours of presentation to receive 48-hour intravenous infusion of 30 µg ⋅ kg^-1 ⋅ d^-1 serelaxin or placebo in addition to standard therapy. The composite primary end point includes: (1) treatment success (moderate/marked improvement in patient-reported dyspnea and physician-assessed signs of congestion on day 2); (2) treatment failure (in-hospital worsening of signs and/or symptoms of heart failure [HF] requiring intensification of intravenous HF therapy or mechanical ventilation, renal/circulatory support, rehospitalization due to HF/renal-failure, or death through day 5); and (3) unchanged status. Secondary end points include time to in-hospital worsening HF through day 5 and all-cause and cardiovascular deaths through day 180.

CONCLUSIONS

RELAX-AHF-ASIA, the largest randomized clinical trial in Asian AHF patients to date, has a novel composite primary end point and the potential to become a hallmark of AHF trials.

Use of High-Sensitivity Troponin T to Identify Patients With Acute Heart Failure at Lower Risk for Adverse Outcomes: An Exploratory Analysis From the RELAX-AHF Trial

OBJECTIVES

The aim of this study was to determine if a baseline high-sensitivity troponin T (hsTnT) value ≤99th percentile upper reference limit (0.014 μg/l ["low hsTnT"]) identifies patients at low risk for adverse outcomes.

BACKGROUND

Approximately 85% of patients who present to emergency departments with acute heart failure are admitted. Identification of patients at low risk might decrease unnecessary admissions.

METHODS

A post-hoc analysis was conducted from the RELAX-AHF (Serelaxin, Recombinant Human Relaxin-2, for Treatment of Acute Heart Failure) trial, which randomized patients within 16 h of presentation who had systolic blood pressure >125 mm Hg, mild to moderate renal impairment, and N-terminal pro-brain natriuretic peptide ≥1,600 ng/l to serelaxin versus placebo. Linear regression models for continuous endpoints and Cox models for time-to-event endpoints were used.

RESULTS

Of the 1,076 patients with available baseline hsTnT values, 107 (9.9%) had low hsTnT. No cardiovascular (CV) deaths through day 180 were observed in the low-hsTnT group compared with 79 CV deaths (7.3%) in patients with higher hsTnT. By univariate analyses, low hsTnT was associated with lower risk for all 5 primary outcomes: 1) days alive and out of the hospital by day 60; 2) CV death or rehospitalization for heart failure or renal failure by day 60; 3) length of stay; 4) worsening heart failure through day 5; and 5) CV death through day 180. After multivariate adjustment, only 180-day CV mortality remained significant (hazard ratio: 0.0; 95% confidence interval: 0.0 to 0.736; p = 0.0234; C-index = 0.838 [95% confidence interval: 0.798 to 0.878]).

CONCLUSIONS

No CV deaths through day 180 were observed in patients with hsTnT levels ≤0.014 μg/l despite high N-terminal pro-brain natriuretic peptide levels. Low baseline hsTnT may identify patients with acute heart failure at very low risk for CV mortality.

Cardiovascular Outcomes According to Systolic Blood Pressure in Patients With and Without Diabetes: An ACCOMPLISH Substudy

To evaluate the effects of achieved systolic blood pressure (SBP) during treatment on cardiovascular (CV) outcomes, the authors measured event rates of a composite primary endpoint (CV death or nonfatal myocardial infarction or stroke) at on-treatment SBPs of ≥140 mm Hg and the 10 mm Hg intervals of <140 mm Hg, <130 mm Hg, and <120 mm Hg in 6459 patients with diabetes (mean age, 67) and 4246 patients without diabetes (mean age, 69) from the Avoiding Cardiovascular Events in Combination Therapy in Patients Living With Systolic Hypertension (ACCOMPLISH) trial. In the diabetic cohort, the primary endpoint was 49% lower (P<.001) at <140 mm Hg than at ≥140 mm Hg, and the separate components of this endpoint were also significantly reduced. Further SBP reductions did not improve outcomes, and at <120 mm Hg they were no longer different (except for stroke) from ≥140 mm Hg. In contrast, in the nondiabetic cohort, the primary endpoint event rate fell steadily (although not significantly) through the decreasing SBP categories until it was reduced by 45% (P=.0413) at <120 mm Hg. Total stroke rates for both the diabetic (-56%, P=.0120) and nondiabetic (-68%, P=.0067) cohorts were lowest at <120 mm Hg, and adverse renal events (serum creatinine increase ≥50%) were significantly lowest in the range of 130 mm Hg to 139 mm Hg for both cohorts. Diabetic patients (<140 mm Hg or <130 mm Hg) and nondiabetic patients (<120 mm Hg) may require different SBP targets for optimal CV protection, although stroke and renal considerations should also influence the selection of blood pressure targets.

Effects of serelaxin in acute heart failure patients with renal impairment: results from RELAX-AHF

BACKGROUND

Serelaxin showed beneficial effects on clinical outcome and trajectories of renal markers in patients with acute heart failure. We aimed to study the interaction between renal function and the treatment effect of serelaxin.

METHODS

In the current post hoc analysis of the RELAX-AHF trial, we included all patients with available estimated glomerular filtration rate (eGFR) at baseline (n = 1132). Renal impairment was defined as an eGFR <60 ml/min/1.73 m(2) estimated by creatinine.

RESULTS

817 (72.2 %) patients had a baseline eGFR <60 ml/min/1.73 m(2). In placebo-treated patients, baseline renal impairment was related to a higher 180 day cardiovascular (HR 3.12, 95 % CI 1.33-7.30) and all-cause mortality (HR 2.81, 95 % CI 1.34-5.89). However, in serelaxin-treated patients, the risk of cardiovascular and all-cause mortality was less pronounced (HR 1.19, 95 % CI 0.54 -2.64; p for interaction = 0.106, and HR 1.15 95 % CI 0.56-2.34 respectively; p for interaction = 0.088). In patients with renal impairment, treatment with serelaxin resulted in a more pronounced all-cause mortality reduction (HR 0.53, 95 % CI 0.34-0.83), compared with patients without renal impairment (HR 1.30, 95 % CI 0.51-3.29).

CONCLUSION

Renal dysfunction was associated with higher cardiovascular and all-cause mortality in placebo-treated patients, but not in serelaxin-treated patients. The observed reduction in (cardiovascular) mortality in RELAX-AHF was more pronounced in patients with renal dysfunction. These observations need to be confirmed in the ongoing RELAX-AHF-2 trial.

Predictors of cardiac morbidity in diabetic, new-onset diabetic and non-diabetic high-risk hypertensive patients: The Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial

Diabetic and new-onset diabetic patients with hypertension have higher cardiac morbidity than patients without diabetes. We aimed to investigate whether baseline predictors of cardiac morbidity, the major constituent of the primary endpoint in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial, were different in patients with diabetes and new-onset diabetes compared to patients without diabetes. In total, 15,245 high-risk hypertensive patients in the VALUE trial were followed for an average of 4.2 years. At baseline, 5250 patients were diabetic by the 1999 World Health Organization criteria, 1298 patients developed new-onset diabetes and 8697 patients stayed non-diabetic during follow-up. Cardiac morbidity was defined as a composite of myocardial infarction and heart failure requiring hospitalization, and baseline predictors were identified by univariate and multivariate stepwise Cox regression analyses. History of coronary heart disease (CHD) and age were the most important predictors of cardiac morbidity in both diabetic and non-diabetic patients. History of CHD, history of stroke and age were the only significant predictors of cardiac morbidity in patients with new-onset diabetes. Predictors of cardiac morbidity, in particular history of CHD and age, were essentially the same in high-risk hypertensive patients with diabetes, new-onset diabetes and without diabetes who participated in the VALUE trial.

Effect of serelaxin on mode of death in acute heart failure: results from the RELAX-AHF study

BACKGROUND

Little is known about mode of death after acute heart failure (AHF) hospitalization. In the RELAX-AHF (Efficacy and Safety of Relaxin for the Treatment of Acute Heart Failure) study, serelaxin, the recombinant form of human relaxin-2, reduced post-discharge mortality at 180 days in selected patients with AHF.

OBJECTIVES

The goal of this study was to assess the effect of serelaxin on specific modes of death in patients with AHF.

METHODS

The RELAX-AHF study randomized 1,161 patients with AHF to 48 h of therapy with intravenous serelaxin or placebo. Patients were followed for vital status through 180 days. A blinded clinical events committee reviewed all deaths and adjudicated a cause of death on the basis of pre-specified criteria. Cox proportional hazard models were used to assess the effect of serelaxin on each mode of death, on the basis of pre-specified groupings of mode of death.

RESULTS

There were 107 deaths (9.3%): 37 (35%) due to HF, 25 (23%) due to sudden death, 15 (14%) due to other cardiovascular (CV) causes, 19 (18%) due to non-CV causes, and 11 (10%) classified as unknown. The treatment effect of serelaxin was most pronounced on other CV deaths (hazard ratio [HR]: 0.29; 95% CI: 0.12 to 0.73; p = 0.005) and sudden death (HR: 0.46; 95% CI: 0.20 to 1.07; p = 0.065). There was no apparent impact of serelaxin treatment on HF deaths or non-CV deaths.

CONCLUSIONS

In the RELAX-AHF study, the effects of serelaxin on mortality were primarily driven by reduction in mortality from other CV causes and sudden death, without apparent impact on HF deaths. (Efficacy and Safety of Relaxin for the Treatment of Acute Heart Failure [RELAX-AHF]; NCT00520806).

Heart rate as a predictor of stroke in high-risk, hypertensive patients with previous stroke or transient ischemic attack

BACKGROUND

Risk factors for first stroke are well established, but less is known about risk factors for recurrent stroke. In the present analysis, we aimed to assess the effect of heart rate and other possible predictors of stroke in a hypertensive population with previous stroke or transient ischemic attack (TIA).

METHODS

The Valsartan Antihypertensive Long-Term Use Evaluation trial was a multicentre, double-masked, randomized controlled, parallel group trial comparing the effects of an angiotensin receptor blocker (valsartan) and a calcium channel blocker (amlodipine) in patients with hypertension and high cardiovascular risk. We used Cox proportional hazard models to investigate the effect of baseline variables on the risk of stroke. Quadratic terms of the continuous variables were entered in the models to test for linearity.

RESULTS

Of 15,245 patients included in the trial, 3014 had a previous stroke or TIA at baseline and were included in the present analysis. Stroke recurrence occurred in 239 patients (7.9%) during a median of 4.5 years of follow-up. Resting heart rate (per 10 beats per minute; hazard ratio [HR], 2.78; 95% confidence interval [CI], 1.18-6.58) and diabetes mellitus at baseline (HR, 1.47; 95% CI, 1.03-2.10) were significantly associated with an increased risk of stroke recurrence in the multivariable analysis.

CONCLUSIONS

In high-risk, hypertensive patients with previous stroke or TIA, resting heart rate was the strongest predictor of recurrent stroke.

Diuretic response in patients with acute decompensated heart failure: characteristics and clinical outcome--an analysis from RELAX-AHF

Aims

We studied the characteristics and clinical outcome related to diuretic response and the effects of serelaxin in patients hospitalized for acute heart failure (AHF).

Methods and results

RELAX-AHF was a double-blind, placebo-controlled trial, enrolling 1161 patients admitted to hospital for AHF who were randomized to 48 h i.v infusions of placebo or serelaxin (30 µg/kg per day) within 16 h from presentation. Diuretic response was defined as Δ weight kg/[(total i.v. dose)/40 mg] + [(total oral dose)/80 mg)] furosemide (or equivalent loop diuretic dose) up to day 5. Median diuretic response was −0.42 (−1.00, −0.14) kg/40 mg. A poor diuretic response was independently associated with Western-like region (Western Europe, North America, Israel, and Poland), lower diastolic blood pressure, the absence of oedema, higher blood urea nitrogen, and lower levels of aspartate aminotransferase and potassium (all P < 0.01). Randomization to serelaxin was associated with lower doses of i.v. loop diuretics and slightly less weight loss, resulting in a neutral effect on diuretic response. Worse diuretic response was independently associated both with less relief of dyspnoea, measured with a visual analogue scale (VAS) at day 5 (primary endpoint; P = 0.0002), and with a higher risk of cardiovascular death or rehospitalization for heart failure or renal failure through day 60 (secondary endpoint, P < 0.0001), but not with increased 180-day cardiovascular mortality (P = 0.507).

Conclusions

In patients hospitalized for AHF, a poor diuretic response was associated with a poor in-hospital and early post-discharge clinical outcome. Serelaxin had a neutral effect on diuretic response.

Trial registration: NCT00520806

Effects of serelaxin in subgroups of patients with acute heart failure: results from RELAX-AHF

AIM

Patients hospitalized for acute heart failure (AHF) differ with respect of many clinical characteristics which may influence their prognosis and response to treatment. We have assessed possible differences in the effects of serelaxin on dyspnoea relief, 60 Day outcomes and 180 Day mortality across patient subgroups in the RELAX-AHF trial.

METHODS AND RESULTS

Subgroups were based on pre-specified covariates (age, sex, race, geographic region, estimated glomerular filtration rate, time from presentation to randomization, baseline systolic blood pressure, history of diabetes, atrial fibrillation, ischaemic heart disease, cardiac devices, i.v. nitrates at randomization). Other covariates which may modify the efficacy of AHF treatment were also analysed. Subgroup analyses did not show any difference in the effects of serelaxin vs. placebo on dyspnoea relief or on the incidence of cardiovascular death or rehospitalizations for heart failure or renal failure at 60 days. Nominally significant interactions between some patient subgroups and the effects of serelaxin on 180 days cardiovascular and all-cause mortality were noted but should be interpreted cautiously due to the number of comparisons and the low incidence of deaths in the subgroups at lower risk.

CONCLUSION

The effects of serelaxin vs. placebo appeared to be similar across subgroups of patients in RELAX-AHF.

Effect of aliskiren on post-discharge outcomes among diabetic and non-diabetic patients hospitalized for heart failure: insights from the ASTRONAUT trial

AIMS

The objective of the Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was to determine whether aliskiren, a direct renin inhibitor, would improve post-discharge outcomes in patients with hospitalization for heart failure (HHF) with reduced ejection fraction. Pre-specified subgroup analyses suggested potential heterogeneity in post-discharge outcomes with aliskiren in patients with and without baseline diabetes mellitus (DM).

METHODS AND RESULTS

ASTRONAUT included 953 patients without DM (aliskiren 489; placebo 464) and 662 patients with DM (aliskiren 319; placebo 343) (as reported by study investigators). Study endpoints included the first occurrence of cardiovascular death or HHF within 6 and 12 months, all-cause death within 6 and 12 months, and change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 1, 6, and 12 months. Data regarding risk of hyperkalaemia, renal impairment, and hypotension, and changes in additional serum biomarkers were collected. The effect of aliskiren on cardiovascular death or HHF within 6 months (primary endpoint) did not significantly differ by baseline DM status (P = 0.08 for interaction), but reached statistical significance at 12 months (non-DM: HR: 0.80, 95% CI: 0.64-0.99; DM: HR: 1.16, 95% CI: 0.91-1.47; P = 0.03 for interaction). Risk of 12-month all-cause death with aliskiren significantly differed by the presence of baseline DM (non-DM: HR: 0.69, 95% CI: 0.50-0.94; DM: HR: 1.64, 95% CI: 1.15-2.33; P < 0.01 for interaction). Among non-diabetics, aliskiren significantly reduced NT-proBNP through 6 months and plasma troponin I and aldosterone through 12 months, as compared to placebo. Among diabetic patients, aliskiren reduced plasma troponin I and aldosterone relative to placebo through 1 month only. There was a trend towards differing risk of post-baseline potassium ≥6 mmol/L with aliskiren by underlying DM status (non-DM: HR: 1.17, 95% CI: 0.71-1.93; DM: HR: 2.39, 95% CI: 1.30-4.42; P = 0.07 for interaction).

CONCLUSION

This pre-specified subgroup analysis from the ASTRONAUT trial generates the hypothesis that the addition of aliskiren to standard HHF therapy in non-diabetic patients is generally well-tolerated and improves post-discharge outcomes and biomarker profiles. In contrast, diabetic patients receiving aliskiren appear to have worse post-discharge outcomes. Future prospective investigations are needed to confirm potential benefits of renin inhibition in a large cohort of HHF patients without DM.

Interaction between baseline and early worsening of renal function and efficacy of renin-angiotensin-aldosterone system blockade in patients with heart failure: insights from the Val-HeFT study

AIMS

We evaluated the effect of (dual) renin-angiotensin-aldosterone system (RAAS) blockade with valsartan and an ACE inhibitor [92.7% of patients were treated with an ACE inhibitor in the Valsartan in Heart Failure Trial (Val-HeFT)] in patients with NYHA class II-IV heart failure (HF) and reduced EF on cardiovascular (CV) death and HF hospitalization by subgroups and by presence of early worsening of renal function (EWRF) and according to baseline estimated glomerular filtration rate (eGFR).

METHODS AND RESULTS

We analysed the data from 5010 patients enrolled in the Val-HeFT study. A total of 2346 (46.8%) patients had baseline renal impairment (i.e. baseline eGFR <60 mL/min/1.73 m(2)). Further, 425 patients (8.6%) had EWRF (i.e. eGFR decrease >20% within 1 month after randomization), whereas 4503 patients (91.4%) had ≤20% decline in eGFR. Overall, the difference between valsartan and placebo on the composite endpoint of CV death and HF hospitalization was significant [P = 0.0005; hazard ratio (HR) 0.83, 95% confidence interval (CI) 0.75-0.92)]. In patients with baseline renal impairment, the difference between the treatment groups was also significant (P = 0.0002; HR 0.76, 95% CI 0.66-0.88). Patients with EWRF had higher risk of CV death and HF hospitalization vs. those without ERWF (P < 0.0001; HR 1.44, 95% CI 1.21-1.71), and within the EWRF group a significant difference was also observed between valsartan and placebo (P = 0.0086; HR 0.63, 95% CI 0.45-0.89). However, the interaction between treatment and eGFR at Month 1 was not significant (P = 0.1160).

CONCLUSION

Benefits were maintained in patients with renal dysfunction at baseline and those who experienced EWRF.

Effect of aliskiren on postdischarge mortality and heart failure readmissions among patients hospitalized for heart failure: the ASTRONAUT randomized trial

IMPORTANCE

Hospitalizations for heart failure (HHF) represent a major health burden, with high rates of early postdischarge rehospitalization and mortality.

OBJECTIVE

To investigate whether aliskiren, a direct renin inhibitor, when added to standard therapy, would reduce the rate of cardiovascular (CV) death or HF rehospitalization among HHF patients.

DESIGN, SETTING, AND PARTICIPANTS

International, double-blind, placebo-controlled study that randomized hemodynamically stable HHF patients a median 5 days after admission. Eligible patients were 18 years or older with left ventricular ejection fraction (LVEF) 40% or less, elevated natriuretic peptides (brain natriuretic peptide [BNP] ≥ 400 pg/mL or N -terminal pro-BNP [NT-proBNP] ≥ 1600 pg/mL), and signs and symptoms of fluid overload. Patients were recruited from 316 sites across North and South America, Europe, and Asia between May 2009 and December 2011. The follow-up period ended in July 2012.

INTERVENTION

All patients received 150 mg (increased to 300 mg as tolerated) of aliskiren or placebo daily, in addition to standard therapy. The study drug was continued after discharge for a median 11.3 months. MAIN OUTCOME MEASURES Cardiovascular death or HF rehospitalization at 6 months and 12 months.

RESULTS

In total, 1639 patients were randomized, with 1615 patients included in the final efficacy analysis cohort (808 aliskiren, 807 placebo). Mean age was 65 years; mean LVEF, 28%; 41% of patients had diabetes mellitus, mean estimated glomerular filtration rate, 67 mL/min/1.73 m2. At admission and randomization, median NT-proBNP levels were 4239 pg/mL and 2718 pg/mL, respectively. At randomization, patients were receiving diuretics (95.9%), β-blockers (82.5%), angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (84.2%), and mineralocorticoid receptor antagonists (57.0%). In total, 24.9% of patients receiving aliskiren (77 CV deaths, 153 HF rehospitalizations) and 26.5% of patients receiving placebo (85 CV deaths, 166 HF rehospitalizations) experienced the primary end point at 6 months (hazard ratio [HR], 0.92; 95% CI, 0.76-1.12; P = .41). At 12 months, the event rates were 35.0% for the aliskiren group (126 CV deaths, 212 HF rehospitalizations) and 37.3% for the placebo group (137 CV deaths, 224 HF rehospitalizations; HR, 0.93; 95% CI, 0.79-1.09; P = .36). The rates of hyperkalemia, hypotension, and renal impairment/renal failure were higher in the aliskiren group compared with placebo.

CONCLUSION AND RELEVANCE

Among patients hospitalized for HF with reduced LVEF, initiation of aliskiren in addition to standard therapy did not reduce CV death or HF rehospitalization at 6 months or 12 months after discharge.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00894387.

Usefulness of heart rate to predict cardiac events in treated patients with high-risk systemic hypertension

A high heart rate (HR) predicts future cardiovascular events. We explored the predictive value of HR in patients with high-risk hypertension and examined whether blood pressure reduction modifies this association. The participants were 15,193 patients with hypertension enrolled in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial and followed up for 5 years. The HR was assessed from electrocardiographic recordings obtained annually throughout the study period. The primary end point was the interval to cardiac events. After adjustment for confounders, the hazard ratio of the composite cardiac primary end point for a 10-beats/min of the baseline HR increment was 1.16 (95% confidence interval 1.12 to 1.20). Compared to the lowest HR quintile, the adjusted hazard ratio in the highest quintile was 1.73 (95% confidence interval 1.46 to 2.04). Compared to the pooled lower quintiles of baseline HR, the annual incidence of primary end point in the top baseline quintile was greater in each of the 5 study years (all p <0.05). The adjusted hazard ratio for the primary end point in the highest in-trial HR heart rate quintile versus the lowest quintile was 1.53 (95% confidence interval 1.26 to 1.85). The incidence of primary end points in the highest in-trial HR group compared to the pooled 4 lower quintiles was 53% greater in patients with well-controlled blood pressure (p <0.001) and 34% greater in those with uncontrolled blood pressure (p = 0.002). In conclusion, an increased HR is a long-term predictor of cardiovascular events in patients with high-risk hypertension. This effect was not modified by good blood pressure control. It is not yet known whether a therapeutic reduction of HR would improve cardiovascular prognosis.

Renal outcomes in hypertensive Black patients at high cardiovascular risk

The ACCOMPLISH trial (Avoiding Cardiovascular events through Combination therapy in Patients Living with Systolic Hypertension) was a 3-year multicenter, event-driven trial involving patients with high cardiovascular risk who were randomized in a double-blinded manner to benazepril plus either hydrochlorothiazide or amlodipine and titrated in parallel to reach recommended blood pressure goals. Of the 8125 participants in the United States, 1414 were of self-described Black ethnicity. The composite kidney disease end point, defined as a doubling in serum creatinine, end-stage renal disease, or death was not different between Black and non-Black patients, although the Blacks were significantly more likely to develop a greater than 50% increase in serum creatinine to a level above 2.6 mg/dl. We found important early differences in the estimated glomerular filtration rate (eGFR) due to acute hemodynamic effects, indicating that benazepril plus amlodipine was more effective in stabilizing eGFR compared to benazepril plus hydrochlorothiazide in non-Blacks. There was no difference in the mean eGFR loss in Blacks between therapies. Thus, benazepril coupled to amlodipine was a more effective antihypertensive treatment than when coupled to hydrochlorothiazide in non-Black patients to reduced kidney disease progression. Blacks have a modestly higher increased risk for more advanced increases in serum creatinine than non-Blacks.

Predictors of systolic BP <140 mmHg and systolic BP level by randomly assigned treatment group (benazepril plus amlodipine or hydrochlorothiazide) in the ACCOMPLISH Study

BACKGROUND

The ACCOMPLISH Trial investigated intensive antihypertensive combination treatment with benazepril + amlodipine (B+A) or benazepril + hydrochlorothiazide (B+H) on cardiovascular outcomes in patients with systolic hypertension. We analyzed the baseline predictors of achieving a systolic blood pressure (SBP) <140 mmHg and achieved SBP level by the end of 12 months in both treatment groups.

METHODS

Baseline and 12-month SBP was available in 10,506 patients, of whom 6250 had diabetes. Univariate and multivariate logistic regression models were used for SBP control at 12 months and multivariable regression models were used for the prediction of SBP at 12 months. A stepwise procedure was used to select significant (p < 0.001) predictors in multivariate analyses.

RESULTS

Mean (± SD) BP fell from 145.4/80.1 (± 18.3/10.7) mmHg at randomization to 132.8/74.7 (± 16.0/9.6) mmHg at 12 months. The main baseline predictors of SBP control <140 mmHg were region (USA >Nordic region) and Caucasian ethnicity in both randomization arms. A higher diastolic BP and the use of lipid lowering agents indicated favorable effects in the B+H arm only. The predictors of uncontrolled SBP were: (i) higher baseline SBP values, (ii) higher number of previous antihypertensive medications in both arms, (iii) the previous use of insulin in the B+A arm, and (iv) pre-trial calcium channel blocker (CCB) use in the B+H arm. Additionally, pre-trial use of thiazides and electrocardiogram (ECG)-left ventricular hypertrophy (LVH) at baseline predicted higher, and smoking lower absolute SBP in the B+A arm and the use of thiazides and proteinuria a higher SBP in the B+H arm.

CONCLUSION

Irrespective of treatment, patients in the USA and Caucasians achieved better SBP control, whereas higher baseline SBP and more previous antihypertensive medications indicated less control. Concomitant use of lipid lowering treatment indicated a better SBP control in the benazepril + hydrochlorothiazide arm. Lastly, insulin use and ECG-LVH in the benazepril + amlodipine arm and proteinuria in the benazepril + hydrochlorothiazide arm indicated poor control.

Cardiovascular events during differing hypertension therapies in patients with diabetes

OBJECTIVES

The aim of this study was to determine which combination therapy in patients with hypertension and diabetes most effectively decreases cardiovascular events.

BACKGROUND

The ACCOMPLISH (Avoiding Cardiovascular Events Through COMbination Therapy in Patients Living With Systolic Hypertension) trial compared the outcomes effects of a renin-angiotensin system blocker, benazepril, combined with amlodipine (B+A) or hydrochlorothiazide (B+H). A separate analysis in diabetic patients was pre-specified.

METHODS

A total of 6,946 patients with diabetes were randomized to treatment with B+A or B+H. A subgroup of 2,842 diabetic patients at very high risk (previous cardiovascular or stroke events) was also analyzed, as were 4,559 patients without diabetes. The primary end point was a composite of cardiovascular death, myocardial infarction, stroke, hospitalization for angina, resuscitated arrest, and coronary revascularization.

RESULTS

In the full diabetes group, the mean achieved blood pressures in the B+A and B+H groups were 131.5/72.6 and 132.7/73.7 mm Hg; during 30 months, there were 307 (8.8%) and 383 (11.0%) primary events (hazard ratio [HR]: 0.79, 95% confidence interval [CI]: 0.68 to 0.92, p = 0.003). For the diabetic patients at very high risk, there were 195 (13.6%) and 244 (17.3%) primary events (HR: 0.77, 95% CI: 0.64 to 0.93, p = 0.007). In the nondiabetic patients, there were 245 (10.8%) and 296 (12.9%) primary events (HR: 0.82, 95% CI: 0.69 to 0.97, p = 0.020). In the diabetic patients, there were clear coronary benefits with B+A, including both acute clinical events (p = 0.013) and revascularizations (p = 0.024). There were no unexpected adverse events.

CONCLUSIONS

In patients with diabetes and hypertension, combining a renin-angiotensin system blocker with amlodipine, compared with hydrochlorothiazide, was superior in reducing cardiovascular events and could influence future management of hypertension in patients with diabetes. (Avoiding Cardiovascular Events Through COMbination Therapy in Patients Living With Systolic Hypertension [ACCOMPLISH]; NCT00170950).

Prevention of atrial fibrillation by Renin-Angiotensin system inhibition a meta-analysis

OBJECTIVES

The authors reviewed published clinical trial data on the effects of renin-angiotensin system (RAS) inhibition for the prevention of atrial fibrillation (AF), aiming to define when RAS inhibition is most effective.

BACKGROUND

Individual studies examining the effects of RAS inhibition on AF prevention have reported controversial results.

METHODS

All published randomized controlled trials reporting the effects of treatment with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers in the primary or secondary prevention of AF were included.

RESULTS

A total of 23 randomized controlled trials with 87,048 patients were analyzed. In primary prevention, 6 trials in hypertension, 2 trials in myocardial infarction, and 3 trials in heart failure were included (some being post-hoc analyses of randomized controlled trials). In secondary prevention, 8 trials after cardioversion and 4 trials assessing the medical prevention of recurrence were included. Overall, RAS inhibition reduced the odds ratio for AF by 33% (p < 0.00001), but there was substantial heterogeneity among trials. In primary prevention, RAS inhibition was effective in patients with heart failure and those with hypertension and left ventricular hypertrophy but not in post-myocardial infarction patients overall. In secondary prevention, RAS inhibition was often administered in addition to antiarrhythmic drugs, including amiodarone, further reducing the odds for AF recurrence after cardioversion by 45% (p = 0.01) and in patients on medical therapy by 63% (p < 0.00001).

CONCLUSIONS

This analysis supports the concept of RAS inhibition as an emerging treatment for the primary and secondary prevention of AF but acknowledges the fact that some of the primary prevention trials were post-hoc analyses. Further areas of uncertainty include potential differences among specific RAS inhibitors and possible interactions or synergistic effects with antiarrhythmic drugs.

Effect of valsartan on the incidence of diabetes and cardiovascular events

BACKGROUND

It is not known whether drugs that block the renin-angiotensin system reduce the risk of diabetes and cardiovascular events in patients with impaired glucose tolerance.

METHODS

In this double-blind, randomized clinical trial with a 2-by-2 factorial design, we assigned 9306 patients with impaired glucose tolerance and established cardiovascular disease or cardiovascular risk factors to receive valsartan (up to 160 mg daily) or placebo (and nateglinide or placebo) in addition to lifestyle modification. We then followed the patients for a median of 5.0 years for the development of diabetes (6.5 years for vital status). We studied the effects of valsartan on the occurrence of three coprimary outcomes: the development of diabetes; an extended composite outcome of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, hospitalization for heart failure, arterial revascularization, or hospitalization for unstable angina; and a core composite outcome that excluded unstable angina and revascularization.

RESULTS

The cumulative incidence of diabetes was 33.1% in the valsartan group, as compared with 36.8% in the placebo group (hazard ratio in the valsartan group, 0.86; 95% confidence interval [CI], 0.80 to 0.92; P<0.001). Valsartan, as compared with placebo, did not significantly reduce the incidence of either the extended cardiovascular outcome (14.5% vs. 14.8%; hazard ratio, 0.96; 95% CI, 0.86 to 1.07; P=0.43) or the core cardiovascular outcome (8.1% vs. 8.1%; hazard ratio, 0.99; 95% CI, 0.86 to 1.14; P=0.85).

CONCLUSIONS

Among patients with impaired glucose tolerance and cardiovascular disease or risk factors, the use of valsartan for 5 years, along with lifestyle modification, led to a relative reduction of 14% in the incidence of diabetes but did not reduce the rate of cardiovascular events. (ClinicalTrials.gov number, NCT00097786.)

Effect of nateglinide on the incidence of diabetes and cardiovascular events

BACKGROUND

The ability of short-acting insulin secretagogues to reduce the risk of diabetes or cardiovascular events in people with impaired glucose tolerance is unknown.

METHODS

In a double-blind, randomized clinical trial, we assigned 9306 participants with impaired glucose tolerance and either cardiovascular disease or cardiovascular risk factors to receive nateglinide (up to 60 mg three times daily) or placebo, in a 2-by-2 factorial design with valsartan or placebo, in addition to participation in a lifestyle modification program. We followed the participants for a median of 5.0 years for incident diabetes (and a median of 6.5 years for vital status). We evaluated the effect of nateglinide on the occurrence of three coprimary outcomes: the development of diabetes; a core cardiovascular outcome that was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure; and an extended cardiovascular outcome that was a composite of the individual components of the core composite cardiovascular outcome, hospitalization for unstable angina, or arterial revascularization.

RESULTS

After adjustment for multiple testing, nateglinide, as compared with placebo, did not significantly reduce the cumulative incidence of diabetes (36% and 34%, respectively; hazard ratio, 1.07; 95% confidence interval [CI], 1.00 to 1.15; P=0.05), the core composite cardiovascular outcome (7.9% and 8.3%, respectively; hazard ratio, 0.94, 95% CI, 0.82 to 1.09; P=0.43), or the extended composite cardiovascular outcome (14.2% and 15.2%, respectively; hazard ratio, 0.93, 95% CI, 0.83 to 1.03; P=0.16). Nateglinide did, however, increase the risk of hypoglycemia.

CONCLUSIONS

Among persons with impaired glucose tolerance and established cardiovascular disease or cardiovascular risk factors, assignment to nateglinide for 5 years did not reduce the incidence of diabetes or the coprimary composite cardiovascular outcomes. (ClinicalTrials.gov number, NCT00097786.)

Predictors of blood pressure response to intensified and fixed combination treatment of hypertension: the ACCOMPLISH study

BACKGROUND

Avoiding Cardiovascular events through COMbination therapy in Patients LIving with Systolic Hypertension (ACCOMPLISH) is an outcome study investigating aggressive antihypertensive combination treatment. It has achieved a larger fraction of overall patients with blood pressure (BP) <140/90 mmHg (73.3%) and diabetic patients <130/80 mmHg (43.3%) at 12 months of follow-up than any other large outcomes trial. We have analyzed baseline predictors of BPs and BP control at 12 months.

METHODS

Blinded baseline and 12-month BP was available in 10,173 patients of whom 6132 had diabetes. Univariate and multivariate logistic regression models were used for BP control at 12 months; simple and multiple regression models were used for absolute BP value at 12 months. A stepwise procedure was used to select significant predictors in multivariate analyses.

RESULTS

Mean (SD) BP fell from 145.5/80.2 mmHg (18.2/10.7 mmHg) at randomization to 132.7/74.7 mmHg (16/9.6 mmHg) at 12 months. The main baseline predictors of achieving BP control were region (USA), Caucasian race and taking lipid-lowering drugs. The predictors of uncontrolled BP were higher baseline systolic BP values, more previous antihypertensive medications, proteinuria and previous thiazide use.

CONCLUSION

Patients in the USA, Caucasians and patients taking lipid-lowering therapy were most likely to reach BP targets with combination therapy. Strong predictors of uncontrolled hypertension were more severe hypertension, an established need for more antihypertensive drugs and target organ damage.

Impact of new-onset diabetes mellitus on cardiac outcomes in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial population

There has been a lot of interest about new-onset diabetes mellitus in recent hypertension trials, but the implications of diabetes development on cardiac outcomes have not been known. In the Valsartan Antihypertensive Long-Term Use Evaluation trial, 15 245 high-risk patients were followed for an average of 4.2 years. At baseline, 5250 patients were diabetic by the 1999 World Health Organization criteria, and among the 9995 nondiabetic patients, 1298 patients developed diabetes during follow-up. We have investigated the influence of diabetes development on outcomes in the Valsartan Antihypertensive Long-Term Use Evaluation trial. The patients with diabetes at baseline and new-onset diabetes were compared with patients who did not develop diabetes by a Cox regression model with adjustment for prespecified covariates (age, diabetes status, left ventricular hypertrophy, baseline coronary heart disease, and randomized study treatment). Patients with diabetes at baseline had the highest cardiac morbidity defined as myocardial infarction and heart failure with a hazard ratio of 2.20 (95% CI: 1.95 to 2.49). The patients with new-onset diabetes had significantly higher cardiac morbidity, especially more congestive heart failure, than those without diabetes, with a hazard ratio of 1.43 (95% CI: 1.16 to 1.77). This indicates that patients who develop diabetes during antihypertensive treatment have cardiac morbidity intermediate between diabetic subjects and those subjects who never had diabetes and that it is of importance to find these patients at risk of diabetes development and optimize lifestyle and medical treatment.

Prediction of cardiovascular outcome by estimated glomerular filtration rate and estimated creatinine clearance in the high-risk hypertension population of the VALUE trial

BACKGROUND

Reduced renal function is predictive of poor cardiovascular outcomes but the predictive value of different measures of renal function is uncertain.

METHODS

We compared the value of estimated creatinine clearance, using the Cockcroft-Gault formula, with that of estimated glomerular filtration rate (GFR), using the Modification of Diet in Renal Disease (MDRD) formula, as predictors of cardiovascular outcome in 15 245 high-risk hypertensive participants in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial. For the primary end-point, the three secondary end-points and for all-cause death, outcomes were compared for individuals with baseline estimated creatinine clearance and estimated GFR < 60 ml/min and > or = 60 ml/min using hazard ratios and 95% confidence intervals. Coronary heart disease, left ventricular hypertrophy, age, sex and treatment effects were included as covariates in the model.

RESULTS

For each end-point considered, the risk in individuals with poor renal function at baseline was greater than in those with better renal function. Estimated creatinine clearance (Cockcroft-Gault) was significantly predictive only of all-cause death [hazard ratio = 1.223, 95% confidence interval (CI) = 1.076-1.390; P = 0.0021] whereas estimated GFR was predictive of all outcomes except stroke. Hazard ratios (95% CIs) for estimated GFR were: primary cardiac end-point, 1.497 (1.332-1.682), P < 0.0001; myocardial infarction, 1.501 (1.254-1.796), P < 0.0001; congestive heart failure, 1.699 (1.435-2.013), P < 0.0001; stroke, 1.152 (0.952-1.394) P = 0.1452; and all-cause death, 1.231 (1.098-1.380), P = 0.0004.

CONCLUSION

These results indicate that estimated glomerular filtration rate calculated with the MDRD formula is more informative than estimated creatinine clearance (Cockcroft-Gault) in the prediction of cardiovascular outcomes.

The Valsartan Antihypertensive Long-Term Use Evaluation (VALUE) Trial

In the main Valsartan Antihypertensive Long-Term Use Evaluation (VALUE) report, we investigated outcomes in 15 245 high-risk hypertensive subjects treated with valsartan- or amlodipine-based regimens. In this report, we analyzed outcomes in 7080 patients (46.4%) who, at the end of the initial drug adjustment period (6 months), remained on monotherapy. Baseline characteristics were similar in the valsartan (N=3263) and amlodipine (N=3817) groups. Time on monotherapy was 3.2 years (78% of treatment exposure time). The average in-trial blood pressure was similar in both groups. Event rates in the monotherapy group were 16% to 39% lower than in the main VALUE trial. In the first analysis, we censored patients when they discontinued monotherapy ("censored"); in the second, we counted events regardless of subsequent therapy (intention-to-treat principle). We also assessed the impact of duration of monotherapy on outcomes. No difference was found in primary composite cardiac end points, strokes, myocardial infarctions, and all-cause deaths with both analyses. Heart failure in the valsartan group was lower both in the censored and intention-to-treat analyses (hazard ratios: 0.63, P=0.004 and 0.78, P=0.045, respectively). Longer duration of monotherapy amplified between-group differences in heart failure. New-onset diabetes was lower in the valsartan group with both analyses (odds ratios: 0.78, P=0.012 and 0.82, P=0.034). Thus, despite lower absolute event rates in monotherapy patients, the relative risks of heart failure and new-onset diabetes favored valsartan. Moreover, these findings support the feasibility of comparative prospective trials in lower-risk hypertensive patients.

Prospective testing for drug-dependent antibodies reduces the incidence of thrombocytopenia observed with the small molecule glycoprotein IIb/IIIa antagonist roxifiban: implications for the etiology of thrombocytopenia

Thrombocytopenia is a relatively common side effect observed during glycoprotein (GP) IIb/IIIa antagonist therapy. With the oral antagonist roxifiban, we observed thrombocytopenia, defined as 50% reduction of platelets over predose values or below 90 000/microL (9 x 10(10)/L), with a frequency of 2% (8 of 386). Thrombocytopenia occurred either early (days 2 to 4) or delayed (days 11 to 16). No additional cases were observed with up to 6 months of treatment. Retrospective analysis provided evidence for drug-dependent antibodies (DDABs) to GP IIb/IIIa in 5 of 6 subjects, suggestive of an immune etiology of thrombocytopenia. The hypothesis that excluding patients based on positive DDAB reaction would reduce the frequency of thrombocytopenia was tested. Patients were screened for DDABs during the study qualification period and, overall, 3.9% of the patients were excluded based on pre-existing DDAB concentrations above a statistically defined medical decision limit. An additional 2.6% were excluded based on therapy-related antibody production during the first 2 weeks. With antibody testing, 0.2% of patients (2 of 1044) developed immune-mediated thrombocytopenia. One case developed a rapidly increasing antibody concentration and presented with thrombocytopenia despite discontinuation of roxifiban therapy. The second case was related to a false-negative test result. The frequency of thrombocytopenia was statistically significantly reduced from 2% to 0.2% (P =.0007) comparing nonscreened and screened patients. Testing for DDABs can reduce the frequency of thrombocytopenia in patients treated with roxifiban and, by analogy, other GP IIb/IIIa antagonists. Thus, DDAB testing may be employed to increase the safety of GP IIb/IIIa antagonists.

Intravenous and subcutaneous weight-based dosing of the low molecular weight heparin tinzaparin (Innohep) in end-stage renal disease patients undergoing chronic hemodialysis

BACKGROUND

Patients with end-stage renal disease are subject to a broad range of thrombotic complications. Low molecular weight heparins (LMWHs) are effective antithrombotic agents; however, they are cleared largely by renal mechanisms, raising uncertainty about their use in renally impaired patients.

METHODS

Twelve chronic hemodialysis subjects were administered two single doses of the LMWH tinzaparin, 75 IU/kg, 2 weeks apart: subcutaneously (SC) on an off-dialysis day and intravenously (IV) just before dialysis.

RESULTS

Mean maximal anti-factor Xa (anti-Xa) activity was 0.33 IU/mL 4.0 hours after SC administration and 1.33 IU/mL 0.25 hours after IV administration. Anti-Xa half-lives were 3.89 and 2.31 hours, respectively. Anti-Xa activity returned to baseline within 24 hours of administration by either route. Consistent with population pharmacokinetic analyses of clinical study subjects with severe renal impairment, anti-Xa clearance after tinzaparin administration was reduced 28% relative to subjects with normal renal function. All 12 study subjects completed hemodialysis without requiring additional anticoagulation. One subject had minimal clotting in the dialyzer drip chamber, and one subject had mild prolonged bleeding at the vascular access site after dialysis needle removal. No major bleeding events occurred.

CONCLUSION

Tinzaparin, 75 IU/kg, SC on an off-dialysis day and IV just before dialysis is well tolerated in chronic hemodialysis patients. The weight-based regimen of 75 IU/kg IV just before dialysis provides adequate anticoagulation. SC weight-based dosing on off-dialysis days is a feasible regimen for further clinical thromboprophylaxis efficacy studies in hemodialysis patients. The risk for clinical overdose in severely renally impaired patients using this weight-based regimen of tinzaparin is unlikely.

Population pharmacodynamics in patients receiving tinzaparin for the prevention and treatment of deep vein thrombosis

OBJECTIVES

We conducted population anticoagulant pharmacodynamic analysis for patients administered the low-molecular weight heparin tinzaparin.

METHODS

Data from 425 patients (2,631 observations) who participated in 2 Phase III clinical studies were utilized in an analysis based on a pharmacodynamic structural model of anti-Xa activity using non-linear mixed effects modeling techniques. Anti-Xa activity from patients participating in a multicenter, randomized, double-blind clinical trial comparing intravenous once daily subcutaneous tinzaparin (175 IU/kg) with heparin for the treatment of deep vein thrombosis (DVT) was first examined using a 2-compartment model with first-order absorption and endogenous anti-Xa activity. Covariates included renal function, body weight, age, gender, race, obesity, concomitant administration of warfarin, and diabetes.

RESULTS

The population estimates and 90% confidence intervals (CI) for oral clearance (CL) and apparent volume of distribution of the plasma compartment (Vc) were 0.0176 l/h/kg (CI = 0.012-0.023) and 0.098 l/kg (CI = 0.088 - 0.109), respectively. The elimination half-life was 3.9 h (CI = 2.5-5.2). These estimates are similar to findings in healthy volunteers. The inter-patient variability in clearance was related to plasma creatinine and percent above ideal body weight. Clearance decreased by 22% for patients with severe renal function impairment (creatinine clearance < 30 ml/min), and by about 25% in obese patients (BMI > 30 kg/m2).

CONCLUSIONS

Changes of these magnitudes were not clinically important in pooled clinical trial safety and efficacy analyses. Body weight was not a significant covariate in the model supporting the observations in earlier well-defined trials, where tinzaparin was dosed on a weight basis (lU/kg). Clearance was not influenced by age, race or gender. The same model was applied to data obtained from a prospective, randomized, double-blind clinical trial comparing tinzaparin (4,500 IU) to enoxaparin (40 mg) once daily in patients undergoing total hip replacement. Model parameters were similar to those previously obtained supporting the extension of these results across dose and indication. Population analysis in patients with disease and heterogeneity indicated similar pharmacodynamics as in volunteers, supporting weight-based dosing and identified the dependence of clearance on obesity and severe renal function, although the magnitude of these effects are probably not clinically significant.

Anticoagulant pharmacodynamics of tinzaparin following 175 iu/kg subcutaneous administration to healthy volunteers

Tinzaparin, a sodium salt of a low-molecular-weight heparin (LMWH) produced via heparinase digestion, is used for the treatment of deep vein thrombosis (DVT) and pulmonary embolism in conjunction with warfarin for the prevention of DVT in patients undergoing hip or knee replacement surgery, and as an anticoagulant in hemodialysis circuits. Its average molecular weight ranges between 5500 and 7500 daltons (Da); the percentage of chains with molecular weight lower than 2000 Da is not more than 10% in the marketed tinzaparin formulation. While this fraction is generally considered pharmacologically inactive, this has never been evaluated in vivo. The importance of the < 2000 Da fraction on the anticoagulant pharmacodynamics of tinzaparin assessed by anti-Xa and anti-IIa activity was studied in a two-way crossover trial. In this trial, 30 healthy volunteers received a single 175 IU/kg subcutaneous administration of tinzaparin containing approximately 3.5% of the < 2000 Da fraction and a tinzaparin-like LMWH containing 18.3% of the < 2000 Da fraction. The anti-Xa/anti-IIa ratios of the drug substances were comparable at 1.5 and 1.7 for tinzaparin and the tinzaparin-like LMWH, respectively. Both formulations were safe and well tolerated. Mean maximum plasma anti-Xa activity (A(max)) was approximately 0.818 IU/ml at 4 h following tinzaparin injection. Mean maximum plasma anti-IIa activity was 0.308 IU/ml at 5 h postdose. Intersubject variation was lower (< 18% for both anti-Xa and anti-IIa metrics) than in previous fixed-dose administration studies. There was no correlation between anti-Xa or anti-IIa AUC or A(max) and bodyweight in the present study supporting the weight-adjusted dosing regimen. Individual anti-Xa and anti-IIa profiles following the single 175 IU/kg subcutaneous administration of the tinzaparin-like LMWH were similar to that obtained with tinzaparin. Based on average equivalence criteria, the two LMWH preparations were determined to be bioequivalent using either anti-Xa or anti-IIa activity as biomarkers. The calculated intrasubject variabilities were low (< 14% for anti-Xa activity and < 18% for anti-IIa activity) yielding little evidence for a significant Subject x Formulation interaction. In summary, anti-Xa and anti-IIa activity following a single subcutaneous administration of tinzaparin 175 IU/kg to healthy volunteers yielded activity consistent with targeted therapeutic levels derived from previous trials in adult DVT patients. Weight-based dosing for the treatment of DVT appears rational based on the reduction in anti-Xa and anti-IIa variability consistent with the recommendation derived from earlier fixed-dose pharmacokinetic studies. Furthermore, differences in the percentage of molecules in the < 2000 Da molecular weight fraction of tinzaparin do not translate into differences in anti-Xa and anti-IIa activity in vivo.

Safety and anticoagulation effect of a low-dose combination of warfarin and aspirin in clinically stable coronary artery disease. Coumadin Aspirin Reinfarction (CARS) Pilot Study Group

The hypothesis that the combination of low-dose aspirin and warfarin therapy is more effective than aspirin alone in secondary prophylaxis after myocardial infarction is to be examined in the Coumadin Aspirin Reinfarction Study. This pilot study addressed the safety and anticoagulation effect of a fixed, low-dose combination in 114 patients (aged 64 +/- 8 years, 85% men) with stable coronary artery disease receiving 3 mg of warfarin plus 80 mg of aspirin daily for 8 weeks. The international normalized ratio (INR) was measured within 72 hours of initial therapy, and weekly. Of the 110 patients with evaluable INRs, 87 patients (79%) maintained the 3 + 80 mg combination, 19 (17%) had the dose reduced to 1 mg warfarin + 80 mg aspirin, and 4 (4%) discontinued therapy because of a confirmed INR of > or = 4.5. At steady state, patients had INRs of 1.48 +/- 0.41 (3 + 80 mg group) and 1.21 +/- 0.23 (1 + 80 mg group), and inter- and intra-patient variability (estimated by the mean of the between- and within-patient SDs at steady state) was 0.49 +/- 0.08 and 0.13 +/- 0.14, respectively. There was no apparent effect of age on INR distribution. Microscopic hematuria was the most frequent (20%) adverse clinical event, but was unrelated to the INR. Three patients required discontinuation of therapy because of bleeding events (persistent hematuria and epistaxis). A fixed low-dose combination of warfarin and aspirin results in a predictable and stable increase in the INR in a large proportion of patients with coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic effects of esmolol, an ultrashort-acting beta blocker

The hemodynamic effects of esmolol were evaluated in 12 male patients at rest (mean age, 51 +/- 10 years) undergoing routine cardiac catheterization. Hemodynamic measurements were obtained during baseline (prior to esmolol), at steady state (during an intravenous infusion of esmolol 300 micrograms/kg/min), and at 30 minutes after stopping esmolol (postinfusion). Esmolol produced hemodynamic effects similar to the effects of other beta blockers. Significant reductions in rate-pressure product (mean decrease, 15%), cardiac index (mean decrease, 17%), stroke volume index (mean decrease, 13%), left ventricular stroke work index (mean decrease, 20%), and left ventricular ejection fraction (mean decrease, 18%) were observed. In contrast to other beta blockers, all hemodynamic effects of esmolol had returned to baseline values within 30 minutes after the infusion stopped. One patient exhibited hypotension during the esmolol infusion; this episode resolved without sequelae after discontinuation of esmolol. In summary, the effects of esmolol at rest on hemodynamic parameters and left ventricular function are similar to other beta-adrenergic blocking agents. Due to its ultrashort half-life, esmolol can be administered safely in critically ill patients whose disease status makes treatment with currently available beta blockers risky.

Effects of esmolol on patients with left ventricular dysfunction

This study examined the effect of esmolol, an ultrashort-acting beta-receptor blocker, in 10 patients with severe left ventricular dysfunction. Simultaneous hemodynamic and radionuclide angiographic measurements were obtained at incremental doses of esmolol (2, 4, 8, 12 and 16 mg/min). At a dose of 4 mg/min, esmolol produced beats blockade: a decrease in heart rate from 91 +/- 4 to 83 +/- 4 beats/min (p less than 0.05) (mean +/- SEM) and a decrease in systolic aortic pressure from 133 +/- 5 to 128 +/- 5 mm Hg (p less than 0.05). At the maximal dose, the heart rate decreased to 79 +/- 3 beats/min (p less than 0.05) and biventricular function was depressed; the left ventricular ejection fraction decreased from 27 +/- 2 to 21 +/- 2% (p less than 0.05) and the right ventricular ejection fraction decreased from 38 +/- 2 to 29 +/- 2% (p less than 0.05). These changes were accompanied by increases in left ventricular end-diastolic volume (p less than 0.05), left ventricular end-systolic volume (p less than 0.05) and pulmonary artery wedge pressure (p less than 0.05), as well as a decrease in cardiac output (p less than 0.05). The hemodynamic abnormalities (which showed considerable interindividual variability) returned to near baseline levels 10 to 30 minutes after infusion was stopped. Thus, esmolol can be administered to patients with severe left ventricular dysfunction. The beneficial effect (beta-adrenergic blockade) is usually achieved with small doses without clinically important hemodynamic changes. At larger doses, however, significant changes in biventricular function may be observed.