Differential effects of beta-blockers in patients with heart failure: A prospective, randomized, double-blind comparison of the long-term effects of metoprolol versus carvedilol

Genetic tailoring of pharmacotherapy in heart failure: optimize the old, while we wait for something new

BACKGROUND

The combination of angiotensin-converting enzyme (ACE) inhibitors and beta-adrenergic receptor blockers remains the essential component of heart failure (HF) pharmacotherapy. However, individual patient responses to these pharmacotherapies vary widely. The variability in response cannot be explained entirely by clinical characteristics, and genetic variation may play a role. The purpose of this review is to examine our current state of understanding of beta-blocker and ACE inhibitor pharmacogenetics in HF.

METHODS AND RESULTS

Beta-blocker and ACE inhibitor pharmacogenetic studies performed in patients with HF were identified from the Pubmed database from 1966 to July 2011. Thirty beta-blocker and 10 ACE inhibitor pharmacogenetic studies in patients with HF were identified. The ACE deletion variant was associated with greater survival benefit from ACE inhibitors and beta-blockers compared with the ACE insertion. Ser49 in the beta-1 adrenergic receptor, the insertion in the alpha-2C adrenergic receptor, and Gln41 in G-protein-coupled receptor kinase 5 are associated with greater survival benefit from beta-blockers, compared with Gly49, the deletion, and Leu41, respectively. However, many of these associations have not been validated.

CONCLUSIONS

The HF pharmacogenetic literature is still in its very early stages, but there are promising candidate genetic variants that may identify which HF patients are most likely to benefit from beta-blockers and ACE inhibitors and patients that may require additional therapies.

Effects of the long-term administration of nebivolol on the clinical symptoms, exercise capacity, and left ventricular function of patients with diastolic dysfunction: results of the ELANDD study

AIMS

We hypothesized that nebivolol, a beta-blocker with nitric oxide-releasing properties, could favourably affect exercise capacity in patients with heart failure and preserved left ventricular ejection fraction (HFPEF).

METHODS AND RESULTS

A total of 116 subjects with HFPEF, in New York Heart Association (NYHA) functional class II-III, with left ventricular ejection fraction (LVEF) >45%, and with echo-Doppler signs of LV diastolic dysfunction, were randomized to 6 months treatment with nebivolol or placebo, following a double-blind, parallel group design. The primary endpoint of the study was the change in 6 min walk test distance (6MWTD) after 6 months. Nebivolol did not improve 6MWTD (from 420 ± 143 to 428 ± 141 m with nebivolol vs. from 412 ± 123 to 446 ± 119 m with placebo, P = 0.004 for interaction) compared with placebo, and the peak oxygen uptake also remained unchanged (peakVO(2); from 17.02 ± 4.79 to 16.32 ± 3.76 mL/kg/min with nebivolol vs. from 17.79 ± 5.96 to 18.59 ± 5.64 mL/kg/min with placebo, P = 0.63 for interaction). Resting and peak blood pressure and heart rate decreased with nebivolol. A significant correlation was found between the change in peak exercise heart rate and that in peakVO(2) (r = 0.391; P = 0.003) for the nebivolol group. Quality of life, assessed using the Minnesota Living with Heart Failure Questionnaire, and NYHA classification improved to a similar extent in both groups, whereas N-terminal pro brain natriuretic peptide (NT-pro BNP) plasma levels remained unchanged.

CONCLUSIONS

Compared with placebo, 6 months treatment with nebivolol did not improve exercise capacity in patients with HFPEF. Its negative chronotropic effect may have contributed to this result.

A randomised, placebo-controlled trial of carvedilol in early familial dilated cardiomyopathy

BACKGROUND

Screening of asymptomatic relatives of patients with dilated cardiomyopathy (DCM) has identified a population of individuals with left ventricular dilatation and/or minimally impaired contraction who are believed to have early disease. A proportion of these individuals with early disease progress to overt cardiomyopathy, however to our knowledge there have been no studies that have examined the impact of early intervention on disease progression.

METHODS

We evaluated 424 asymptomatic relatives in 110 families of probands with DCM and identified 102 individuals (24%) with suspected "early disease" (EDCM). Thirty-two EDCM subjects were randomised into a six-month placebo-controlled trial of the β-blocker, carvedilol. Transthoracic echocardiography and plasma nt-proBNP levels were measured at baseline and repeated at six months. The primary trial endpoint was change in left ventricular end-systolic diameter after six months. Subjects completing six months of blinded trial therapy were offered open-label carvedilol and then observed over an extended period with repeated clinical evaluation and echocardiography.

RESULTS

At baseline, left ventricular dimensions, systolic function and plasma nt-proBNP levels were similar in carvedilol and placebo groups. There were no significant changes observed in these parameters in either treatment group after six months, however reductions in end-diastolic diameter (% predicted) were observed in carvedilol-treated subjects (P=0.002) during an open-label median follow-up of 32 months (range: 13-56 months).

CONCLUSIONS

In an asymptomatic population of individuals with EDCM, treatment with carvedilol for six months had no effect on echocardiographic left ventricular dimensions or systolic function, however longer-term treatment may reverse left ventricular remodelling (Australian Clinical Trials Registry N012605000204640).

Comparative long term effects of nebivolol and carvedilol in hypertensive heart failure patients

BACKGROUND

Beta-blockers improve left ventricular (LV) systolic function and prognosis in patients with chronic heart failure (CHF), but their different pleiotropic properties may influence their cardiovascular effects. This open-label study compared the effects of long-term treatment with nebivolol versus carvedilol on LV ejection fraction (LVEF), in hypertensive CHF patients. Secondary end points were to assess the effect of the 2 beta-blockers on exercise capacity and clinical outcome.

METHODS AND RESULTS

A total of 160 hypertensive CHF patients, with LVEF <40% and in New York Heart Association (NYHA) functional class I, II, or III, were randomly assigned to receive nebivolol or carvedilol for 24 months. At baseline and at the end of treatment, all patients underwent clinical evaluation, echocardiography, and 6-minute walking test. The target doses were 10 mg/d for nebivolol and 50 mg/d for carvedilol. Compared with baseline values, LVEF increased by a similar extent in the carvedilol (C) and nebivolol (N) groups (C from 36.1% (SD 1.5%) to 40.9% (SD 1.9%), P < .001; N from 34.1% (SD 1.8%) to 38.5% (SF 2.2%), P < .001). Heart rate and NYHA functional class decreased significantly in both groups, and the 6-minute walking distance increased (C from 420 m (SD 104 m) to 490 m (SD 115 m), P < .001; N from 421 m (SD 118 m) to 487 m (SD 138 m), P < .001). During 24 months, 21 carvedilol recipients (26%) and 18 nebivolol recipients (22%) had cardiac events, including 3 and 4 deaths, respectively.

CONCLUSION

In the long term, nebivolol and carvedilol appear to be similarly effective in the treatment of hypertensive patients with CHF.

The Role of Carvedilol in the Treatment of Dilated and Anthracyclines-Induced Cardiomyopathy

Although chronic sympathetic activation provides inotropic and chronotropic support to the failing heart, such activation may also have deleterious effects, including the direct cardiotoxic effects of catecholamines, activation of the renin-angiotensin-aldosterone system and an increase in myocardial oxygen demand. These observations indicate that β-blockade might be beneficial in the treatment of heart failure resulting from dilated cardiomyopathy or ischaemic heart disease. Carvedilol is a non-selective β-blocker acting on β1-, β2-, and α1-adrenoceptors. It possesses potent anti-oxidant and anti-apoptotic properties, along with neuroprotective, vasculoprotective, cardioprotective effects, and it has reduced overall mortality in patients with heart failure in controlled clinical trials. Its role in treating cardiomyopathy requires focus. The fact that anthracyclines are cardiotoxic seriously narrows their therapeutic index in cancer therapy. The cardiotoxic risk increases with the cumulative dose and may lead to congestive heart failure and dilated cardiomyopathy in adults and in children. This review focuses on recent research regarding the beneficial effects of carvedilol in the treatment of dilated cardiomyopathy and to revisit the available evidence on the cardioprotection of carvedilol when associated with anthracycline and to explain the mechanisms underlying the benefits of their co-administration.

The role of beta-blockers in the treatment of chronic heart failure

The introduction of beta-blockers in the treatment of cardiovascular diseases was a milestone and one of the most important contributions to clinical medicine in the 20th century. For many years, beta-blockers were considered contraindicated in patients with chronic heart failure owing to the negative inotropic action of these substances. With increasing evidence of neurohormonal activation in heart failure patients, there was a focus on the potential role of beta-blockers in the treatment of chronic heart failure. Several large randomized placebo- controlled clinical trials have shown favorable effects of beta-blockers on mortality and morbidity in heart failure patients with impaired systolic function. Beneficial effects in patients with preserved left ventricular systolic function are less clear. A reduction in heart rate is one of several mechanisms by which beta-blockers exert beneficial effects in chronic heart failure. In this article we present results from major clinical trials examining beta-blocker treatment in chronic heart failure patients and discuss heart rate as a therapeutic target in these patients.

A histamine H₂ receptor blocker ameliorates development of heart failure in dogs independently of β-adrenergic receptor blockade

Histamine has a positive inotropic effect on ventricular myocardium and stimulation of histamine H₂ receptors increases the intracellular cAMP level via Gs protein, as dose stimulation of β-adrenergic receptors, and worsens heart failure. To test whether a histamine H₂ receptor blocker had a beneficial effect in addition to β-adrenergic receptor blockade, we investigated the cardioprotective effect of famotidine, a histamine H₂ receptor blocker, in dogs receiving a β-blocker. We induced heart failure in dogs by rapid ventricular pacing (230 beats/min). Animals received no drugs (control group), famotidine (1 mg/kg daily), carvedilol (0.1 mg/kg daily), or carvedilol plus famotidine. Both cardiac catheterization and echocardiography were performed before and 4 weeks after the initiation of pacing. Immunohistochemical studies showed the appearance of mast cells and histamine in the myocardium after 4 weeks of pacing. In the control group, the left ventricular ejection fraction (LVEF) was decreased after 4 weeks compared with before pacing (71 ± 2 vs. 27 ± 2%, p < 0.05) and mean pulmonary capillary wedge pressure (PCWP) was increased (8 ± 1 vs. 19 ± 3 mmHg). Famotidine ameliorated the decrease of LVEF and increase of PCWP, while the combination of carvedilol plus famotidine further improved both parameters compared with the carvedilol groups. These beneficial effects of famotidine were associated with a decrease of the myocardial cAMP level. Histamine H₂ receptor blockade preserves cardiac systolic function in dogs with pacing-induced heart failure, even in the presence of β-adrenergic receptor blockade. This finding strengthens the rationale for using histamine H₂ blockers in the treatment of heart failure.

Role of beta-adrenergic receptor gene polymorphisms in the long-term effects of beta-blockade with carvedilol in patients with chronic heart failure

BACKGROUND

Beta-blockers are mainstay of current treatment of heart failure (HF). Beta-adrenergic receptors (AR) single nucleotide gene polymorphisms (SNPs) may influence the sensitivity and density of beta-AR. We assessed the relation between three common beta-AR SNPs and the response to carvedilol administration.

METHODS AND RESULTS

We studied 183 consecutive patients with chronic HF due to ischemic or nonischemic cardiomyopathy, a LV ejection fraction (LVEF) < or = 0.35, not previously treated with beta-blockers. Each patient underwent gated-SPECT radionuclide ventriculography, cardiopulmonary exercise testing and invasive hemodynamic monitoring at baseline and after 12 months of carvedilol administration at maintenance dosages. The beta1-AR gene Arg389Gly and the beta2-AR gene Arg16Gly SNPs were not related to the response to carvedilol administration. Homozygotes for the Glu27Glu allele showed a greater increase in the LVEF, compared to the other patients (+13.0 +/- 12.2% versus +7.1 +/- 8.1% in the Gln27Gln homozygotes, and 8.3 +/- 11.4% units in the Gln27Glu heterozygotes; p = 0.022 by ANOVA). Glu27Glu homozygotes also showed a greater decline in the pulmonary wedge pressure both at rest and at peak exercise. Gln27Glu SNP was selected amongst the determinants of the LVEF response to carvedilol at multivariable analysis, in addition to the cause of cardiomyopathy, baseline systolic blood pressure and the dose of carvedilol administered.

CONCLUSION

Beta1-AR Arg389Gly and beta2-AR Arg16Gly SNPs are not related to the response to carvedilol therapy. In contrast, the Gln27Glu SNP is a determinant of the LVEF response to this agent in patients with chronic HF.

Differences between beta-blockers in patients with chronic heart failure and chronic obstructive pulmonary disease: a randomized crossover trial

OBJECTIVES

The purpose of this study was to determine the respiratory, hemodynamic, and clinical effects of switching between beta1-selective and nonselective beta-blockers in patients with chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD).

BACKGROUND

Carvedilol, metoprolol succinate, and bisoprolol are established beta-blockers for treating CHF. Whether differences in beta-receptor specificities affect lung or vascular function in CHF patients, particularly those with coexistent COPD, remains incompletely characterized.

METHODS

A randomized, open label, triple-crossover trial involving 51 subjects receiving optimal therapy for CHF was conducted in 2 Australian teaching hospitals. Subjects received each beta-blocker, dose-matched, for 6 weeks before resuming their original beta-blocker. Echocardiography, N-terminal pro-hormone brain natriuretic peptide, central augmented pressure from pulse waveform analysis, respiratory function testing, 6-min walk distance, and New York Heart Association (NYHA) functional class were assessed at each visit.

RESULTS

Of 51 subjects with a mean age of 66 +/- 12 years, NYHA functional class I (n = 6), II (n = 29), or III (n = 16), and left ventricular ejection fraction mean of 37 +/- 10%, 35 had coexistent COPD. N-terminal pro-hormone brain natriuretic peptide was significantly lower with carvedilol than with metoprolol or bisoprolol (mean: carvedilol 1,001 [95% confidence interval (CI): 633 to 1,367] ng/l; metoprolol 1,371 [95% CI: 778 to 1,964] ng/l; bisoprolol 1,349 [95% CI: 782 to 1,916] ng/l; p < 0.01), and returned to baseline level on resumption of the initial beta-blocker. Central augmented pressure, a measure of pulsatile afterload, was lowest with carvedilol (carvedilol 9.9 [95% CI: 7.7 to 12.2] mm Hg; metoprolol 11.5 [95% CI: 9.3 to 13.8] mm Hg; bisoprolol 12.2 [95% CI: 9.6 to 14.7] mm Hg; p < 0.05). In subjects with COPD, forced expiratory volume in 1 s was lowest with carvedilol and highest with bisoprolol (carvedilol 1.85 [95% CI: 1.67 to 2.03] l/s; metoprolol 1.94 [95% CI: 1.73 to 2.14] l/s; bisoprolol 2.0 [95% CI: 1.79 to 2.22] l/s; p < 0.001). The NYHA functional class, 6-min walk distance, and left ventricular ejection fraction did not change. The beta-blocker switches were well tolerated.

CONCLUSIONS

Switching between beta1-selective beta-blockers and the nonselective beta-blocker carvedilol is well tolerated but results in demonstrable changes in airway function, most marked in patients with COPD. Switching from beta1-selective beta-blockers to carvedilol causes short-term reduction of central augmented pressure and N-terminal pro-hormone brain natriuretic peptide. (Comparison of Nonselective and Beta1-Selective Beta-Blockers on Respiratory and Arterial Function and Cardiac Chamber Dynamics in Patients With Chronic Stable Congestive Cardiac Failure; Australian New Zealand Clinical Trials Registry, ACTRN12605000504617).

Clinical updates on carvedilol: a first choice beta-blocker in the treatment of cardiovascular diseases

IMPORTANCE OF THE FIELD

Carvedilol, a non-selective beta-blocker, has recently drawn attention because of its therapeutic benefits over other prescribed analogues for the treatment of cardiovascular diseases (CVDs).

AREAS COVERED IN THIS REVIEW

The present review attempts to present the clinical efficacy of carvedilol in comparison to other available beta-blockers. The literature search was carried out in three electronic databases (Unbound Medline, Pubmed and Sciencedirect) and internet search engines (Scirus and Google Scholar) without time constraints to ensure maximum literature coverage.

WHAT THE READER WILL GAIN

A relatively large number of comparative studies have revealed that carvedilol has advantage over traditional beta-blockers with respect to hemodynamic and metabolic effects, due to its unique non-selective alpha-/beta-adrenoceptor affinity. Such results indicate its safe and effective therapeutic application particularly in patients with complicated CVDs, even in pediatric and geriatric patients.

TAKE HOME MESSAGE

The therapeutic profile of carvedilol indicates its suitability for treatment of complicated CVDs than other non-selective beta-blockers. However, there is a limitation in terms of its dose due to its low bioavailability (approximately 25%). Therefore, there is still need for bioavailability enhancement and dose reduction to further improve the therapeutic efficacy of the drug.

Role of β-blocker therapy in pediatric heart failure

Heart failure is becoming an increasingly common and significant problem in the field of pediatric cardiology. The numerous types of cardiomyopathies, and more recently, long-term survival of patients with congenital heart disease, have added to a growing patient population. Over the last several decades, our knowledge base regarding mechanisms of disease and therapeutic intervention in adult patients with heart failure has drastically changed. The most recent and important breakthrough in the pharmacologic treatment of heart failure has been the particular role of β-blocker therapy. This medication has led to significant improvements in survival and symptoms in adults, with less convincing findings in limited studies in pediatrics. The ability to study the benefits of this therapy in patients has been challenging owing to the heterogeneity of the patient population and lack of large sample sizes. However, as we investigate the mechanisms behind the disease process, the differences that exist between disease conditions and ages, and the significant alterations that may exist at the molecular and genetic level, our understanding of β-blocker therapy in pediatric heart failure will improve, and ultimately may lead to patient-specific therapy.

Cheyne-stokes respiration and prognosis in modern-treated congestive heart failure

In patients with congestive heart failure (CHF), a high prevalence of sleep-disordered breathing has been described. Cheyne-Stokes respiration (CSR) is present in up to 40% of patients with CHF. During the last decade, the medical treatment has been substantially improved. This study was designed to analyze the prognosis of CSR in modern-treated patients with CHF. For this purposes, in 57 patients with CHF who received modern treatment, a 5-year follow-up after initial full night polysomnography was performed. The mean follow-up period was 38 ± 18 months. Mean age was 62 ± 13 years and the mean ejection fraction was 25 ± 7 percent. Respiratory polygraphy revealed CSR with a respiratory disturbance index >5 per hour of sleep in 39 of 57 patients. Twelve patients died. CSR was only characterized by a tendency of worsening (log-rank test, p = 0.25). However, there was a significant difference toward positive outcome for patients who received cardiac resynchronization therapy (log-rank test, p = 0.036). Using Multivariate Cox’s proportional hazard regression with the factors resynchronization and CSR, the effect of resynchronization was almost significant (p = 0.08). In conclusion, no significant change of Cheyne-Stokes prevalence can be found in our small group of modern-treated patients with CHF. Cardiac resynchronization therapy was associated with improved patient outcome.

Beta-receptor selectivity of carvedilol and metoprolol succinate in patients with heart failure (SELECT trial): a randomized dose-ranging trial

STUDY OBJECTIVE

To determine whether metoprolol succinate (a beta(1)-selective beta-blocker) remains beta(1)-selective compared with carvedilol (a nonselective beta-blocker) during upward titration of doses in patients with American College of Cardiology (ACC) stage C heart failure.

DESIGN

Prospective, randomized, parallel-arm study. Setting. General clinical research center.

PATIENTS

Twenty-five beta-blocker-naïve adults with New York Heart Association functional classes II or III heart failure (i.e., ACC stage C). Intervention. Patients received either immediate-release carvedilol 3.125 mg twice/day or controlled-release metoprolol succinate 25 mg once/day; doses were titrated upward by doubling the dose every 2 weeks until reaching a maximum tolerated dose or a goal dose of carvedilol 25 mg twice/day and metoprolol 200 mg/day. Before each dose titration, terbutaline (a beta-receptor agonist) was infused at 6 mg/kg over 1 hour for determination of beta(2)-blockade.

MEASUREMENTS AND MAIN RESULTS

Patients were studied at baseline and after each dose titration of metoprolol succinate (at 25, 50, 100, and 200 mg once/day) and immediate-release carvedilol (at 3.125, 6.25, 12.5, and 25 mg twice/day). Glucose and potassium concentrations were measured twice serially at baseline, every 10 minutes during infusion, every 15 minutes for the first hour after infusion, and every 30 minutes for the second hour after infusion. The median area under the concentration-time curve (AUC) was calculated for changes in glucose and potassium concentrations. As assessed by glucose AUC, there was no significant difference in the degree of beta(2)-blockade between metoprolol 200 mg and carvedilol 25 mg. In contrast to these data, the degree of beta(2)-blockade as assessed by potassium AUC was greater for carvedilol compared with metoprolol across all doses.

CONCLUSION

In this ACC stage C heart failure population, carvedilol was nonselective at all clinically relevant doses, whereas metoprolol succinate was beta(1)-selective at low doses and became progressively nonselective at higher doses.

Survival among patients with left ventricular systolic dysfunction treated with atenolol

Metoprolol succinate, carvedilol, and bisoprolol are approved for use in heart failure. Other beta-blockers have been found to be inferior (metoprolol tartrate) or have not been studied (atenolol). The authors compared all-cause mortality following treatment with either atenolol, carvedilol, or metoprolol tartrate for 974 patients with left ventricular function < or =40%. The unadjusted mortality at 6 months was lower with atenolol (3.2%) and carvedilol (4.2%) when compared with metoprolol tartrate (7.5%, P< or =.039). However, patients with atenolol were older but had less prior heart failure. After adjustment for the propensity to be treated with atenolol, patients actually treated with atenolol had a significantly lower risk of death compared with treatment with metoprolol tartrate and comparable outcome to those treated with carvedilol. These results suggest that atenolol may be useful for patients with heart failure treatment and highlight the need for a randomized trial comparing atenolol with established beta-blockers.

Therapeutic effect of {beta}-adrenoceptor blockers using a mouse model of dilated cardiomyopathy with a troponin mutation

AIMS

Extensive clinical studies have demonstrated that beta-adrenoceptor blocking agents (beta-blockers) are beneficial in the treatment of chronic heart failure, which is due to various aetiologies, including idiopathic dilated cardiomyopathy (DCM) and ischaemic heart disease. However, little is known about the therapeutic efficacy of beta-blockers in the treatment of the inherited form of DCM, of which causative mutations have recently been identified in various genes, including those encoding cardiac sarcomeric proteins. Using a mouse model of inherited DCM with a troponin mutation, we aim to study the treatment benefits of beta-blockers.

METHODS AND RESULTS

Three different types of beta-blockers, carvedilol, metoprolol, and atenolol, were orally administered to a knock-in mouse model of inherited DCM with a deletion mutation DeltaK210 in the cardiac troponin T gene (TNNT2). Therapeutic effects were examined on the basis of survival and myocardial remodelling. The lipophilic beta(1)-selective beta-blocker metoprolol was found to prevent cardiac dysfunction and remodelling and extend the survival of knock-in mice. Conversely, both the non-selective beta-blocker carvedilol and the hydrophilic beta(1)-selective beta-blocker atenolol had no beneficial effects on survival and myocardial remodelling in this mouse model of inherited DCM.

CONCLUSION

The highly lipophilic beta(1)-selective beta-blocker metoprolol, known to prevent ventricular fibrillation via central nervous system-mediated vagal activation, may be especially beneficial to DCM patients showing a family history of frequent sudden cardiac death, such as those with a deletion mutation DeltaK210 in the TNNT2 gene.

Controlled-release carvedilol in the management of systemic hypertension and myocardial dysfunction

Cardiovascular disease is the leading cause of death worldwide. Within the treatment armamentarium, beta-blockers have demonstrated efficacy across the spectrum of cardiovascular disease--from modification of a risk factor (ie, hypertension) to treatment after an acute event (ie, myocardial infarction). Recently, the use of beta-blockers as a first-line therapy in hypertension has been called into question. Moreover, beta-blockers as a class are saddled with a misperception of having poor tolerability. However, vasodilatory beta-blockers such as carvedilol have a different hemodynamic action that provides the benefits of beta-blockade with the addition of vasodilation resulting from alpha 1-adrenergic receptor blockade. Vasodilation reduces total peripheral resistance, which may produce an overall positive effect on tolerability. Recently, a new, controlled-release carvedilol formulation has been developed that provides the clinical efficacy of carvedilol but is indicated for once-daily dosing. This review presents an overview of the clinical and pharmacologic carvedilol controlled-release data.

Effects of exercise training on health status in patients with chronic heart failure: HF-ACTION randomized controlled trial

CONTEXT

Findings from previous studies of the effects of exercise training on patient-reported health status have been inconsistent.

OBJECTIVE

To test the effects of exercise training on health status among patients with heart failure.

DESIGN, SETTING, AND PATIENTS

Multicenter, randomized controlled trial among 2331 medically stable outpatients with heart failure with left ventricular ejection fraction of 35% or less. Patients were randomized from April 2003 through February 2007.

INTERVENTIONS

Usual care plus aerobic exercise training (n = 1172), consisting of 36 supervised sessions followed by home-based training, vs usual care alone (n = 1159). Randomization was stratified by heart failure etiology, which was a covariate in all models.

MAIN OUTCOME MEASURES

Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary scale and key subscales at baseline, every 3 months for 12 months, and annually thereafter for up to 4 years. The KCCQ is scored from 0 to 100 with higher scores corresponding to better health status. Treatment group effects were estimated using linear mixed models according to the intention-to-treat principle.

RESULTS

Median follow-up was 2.5 years. At 3 months, usual care plus exercise training led to greater improvement in the KCCQ overall summary score (mean, 5.21; 95% confidence interval, 4.42 to 6.00) compared with usual care alone (3.28; 95% confidence interval, 2.48 to 4.09). The additional 1.93-point increase (95% confidence interval, 0.84 to 3.01) in the exercise training group was statistically significant (P < .001). After 3 months, there were no further significant changes in KCCQ score for either group (P = .85 for the difference between slopes), resulting in a sustained, greater improvement overall for the exercise group (P < .001). Results were similar on the KCCQ subscales, and no subgroup interactions were detected.

CONCLUSIONS

Exercise training conferred modest but statistically significant improvements in self-reported health status compared with usual care without training. Improvements occurred early and persisted over time.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00047437.

Facilitatory interplay in alpha 1a and beta 2 adrenoceptor function reveals a non-Gq signaling mode: implications for diversification of intracellular signal transduction

Agonist occupied alpha(1)-adrenoceptors (alpha(1)-ARs) engage several signaling pathways, including phosphatidylinositol hydrolysis, calcium mobilization, arachidonic acid release, mitogen-activated protein (MAP) kinase activation, and cAMP accumulation. The natural agonist norepinephrine (NE) activates with variable affinity and intrinsic efficacy all adrenoceptors, and in cells that coexpress alpha(1)- and beta-AR subtypes, such as cardiomyocytes, this leads to coactivation of multiple downstream pathways. This may result in pathway cross-talk with significant consequences to heart physiology and pathologic state. To dissect signaling components involved specifically in alpha(1A)- and beta(2)-AR signal interplay, we have developed a recombinant model system that mimics the levels of receptor expression observed in native cells. We followed intracellular Ca(2+) mobilization to monitor in real time the activation of both G(q) and G(s) pathways. We found that coactivation of alpha(1A)- and beta(2)-AR by the nonselective agonist NE or via a combination of the highly selective alpha(1A)-AR agonist A61603 and the beta-selective agonist isoproterenol led to increases in Ca(2+) influx from the extracellular compartment relative to stimulation with A61603 alone, with no effect on the associated transient release of Ca(2+) from intracellular stores. This effect became more evident upon examination of an alpha(1A)-AR variant exhibiting a partial defect in coupling to G(q), and we attribute it to potentiation of a non G(q)-pathway, uncovered by application of a combination of xestospongin C, an endoplasmic reticulum inositol 1,4,5-triphosphate receptor blocker, and 2-aminoethoxydiphenyl borate, a nonselective storeoperated Ca(2+) entry channel blocker. We also found that stimulation with A61603 of a second alpha(1A)-AR variant entirely unable to signal induced no Ca(2+) unless beta(2)-AR was concomitantly activated. These results may be accounted for by the presence of alpha(1A)/beta(2)-AR heterodimers or alternatively by specific adrenoceptor signal cross-talk resulting in distinct pharmacological behavior. Finally, our findings provide a new conceptual framework to rationalize outcomes from clinical studies targeting alpha- and beta-adrenoceptors.

The beta1-adrenergic receptor mediates the pharmacogenetic interaction of the ACE D allele and beta-blockers

The role of beta-receptor selectivity for the interaction between the angiotensin-converting enzyme (ACE) insertion/deletion polymorphism and beta-blocker therapy was investigated in 479 subjects with left ventricular dysfunction. Subjects were separated into no beta-blocker, beta1 -selective, and nonselective beta-blocker treatment groups. The D allele adversely affected transplant-free survival for subjects not on beta-blockers (p= 0.004). Treatment with selective beta1-blockers eliminated the impact of the D allele (p= 0.51) in a manner similar to nonselective beta1,2-blockers (p= 0.80). Treatment with beta1-blockers was sufficient to eliminate the adverse impact of the ACE D allele, suggesting this pharmacogenetic interaction is mediated through the beta1-receptor.

Pediatric heart failure therapy with beta-adrenoceptor antagonists

Management of chronic heart failure in pediatrics has been altered by the adult literature showing improvements in mortality and hospitalization rates with the use of beta-adrenoceptor antagonists (beta-blockers) for routine therapy of all classes of ischemic and non-ischemic heart failure. Many pediatric heart failure specialists have incorporated these agents into their routine management of pediatric heart failure related to dilated cardiomyopathy or ventricular dysfunction in association with congenital heart disease. Retrospective and small prospective case series have shown encouraging improvements in cardiac function and symptoms, but interpretation has been complicated by the high rate of spontaneous recovery in pediatric patients. A recently completed pediatric double-blind, randomized, placebo-controlled clinical trial showed no difference between placebo and two doses of carvedilol over a 6-month period of follow-up, with significant improvement of all three groups over the course of evaluation. Experience with adults has suggested that only certain beta-blockers, including carvedilol, bisoprolol, nebivolol, and metoprolol succinate, should be used in the treatment of heart failure and that patients with high-grade heart failure may derive the most benefit. Other studies surmise that early or prophylactic use of these medications may alter the risk of disease progression in some high-risk subsets, such as patients receiving anthracyclines or those with muscular dystrophy. This article reviews these topics using experience as well as data from all the recent pediatric studies on the use of beta-blockers to treat congestive heart failure, especially when related to systolic ventricular dysfunction.

Analysis of randomized controlled trials on the effect of magnitude of heart rate reduction on clinical outcomes in patients with systolic chronic heart failure receiving beta-blockers

Beta blockers improve cardiac function and prolong survival in patients with systolic chronic heart failure (CHF). However, the exact mechanisms underlying these benefits are uncertain. Specifically, it is unclear whether a close relation exists between heart rate (HR) reduction and clinical outcomes with these agents. This hypothesis was therefore tested within randomized controlled trials of beta blockers in systolic CHF. Left ventricular ejection fraction (LVEF) and HR values at baseline and study end were obtained from available beta-blocker randomized clinical trials. The relation between change in HR and all-cause mortality as well as the LVEF was determined using regression analysis. Thirty-five trials, which included 22,926 patients with a mean follow-up duration of 9.6 months, were analyzed for all-cause mortality, the LVEF, and HR. There was a close relation between all-cause annualized mortality rate and HR (adjusted R2 = 0.51, p = 0.004). A strong correlation between change in HR and change in LVEF (adjusted R2 = 0.48, p = 0.000) was also observed. When only trials with >100 patients were included, an even tighter correlation was seen (adjusted R2 = 0.60, p = 0.0004). In conclusion, these analyses indicate that a major contributor to the clinical benefits of beta-blocker therapy in systolic CHF may be the HR-lowering effect of these agents. Therefore, the magnitude of HR reduction may be more important than the achievement of target dose in beta-blocker treatment of systolic CHF.

Therapies for acute heart failure in patients with reduced kidney function: a community-based perspective

BACKGROUND

Limited data exist describing the management of patients with decreased kidney function at the time of hospital presentation for acute heart failure (HF).

STUDY DESIGN

Nonconcurrent prospective study.

SETTING & PARTICIPANTS

Patients hospitalized with clinical findings of decompensated HF (n = 4,350) at all 11 greater Worcester, MA, medical centers in 1995 and 2000. Patients were categorized into varying levels of kidney function based on their estimated glomerular filtration rate (eGFR).

PREDICTOR

GFR estimates from serum creatinine levels measured at the time of hospital admission.

OUTCOMES

Hospital receipt of angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs), beta-blockers, digoxin, and diuretics.

MEASUREMENTS

Hospital charts were reviewed for prescribing of disease-modifying cardiac therapies, as well as therapies designed to provide symptomatic relief from HF.

RESULTS

Average eGFR in our study sample was 64.4 +/- 33.1 mL/min/1.73 m(2), and patients were categorized further into 3 eGFR levels of less than 30 (n = 569), 30 to 59 (n = 1,488), and 60 mL/min/1.73 m(2) or greater (n = 2,293) for comparative purposes. Patients with greater eGFRs (>or=60 mL/min/1.73 m(2)) were more likely to be treated with ACE inhibitors/ARBs (56% versus 39%) and digoxin (51% versus 46%) during hospitalization for HF than patients with lower eGFRs (<30 mL/min/1.73 m(2); P < 0.05). Patients with lower eGFRs (<30 mL/min/1.73 m(2)) were more likely to be prescribed beta-blockers than patients with greater eGFRs (>or=60 mL/min/1.73 m(2); 46% versus 39%; P < 0.01). Use of ACE inhibitors/ARBs increased between 1995 and 2000 in 2 of the 3 eGFR groups examined: eGFRs less than 30 mL/min/1.73 m(2) (33% in 1995; 42% in 2000) and eGFRs of 60 mL/min/1.73 m(2) or greater (51% in 1995; 59% in 2000). Use of beta-blockers increased appreciably in all 3 eGFR groups (<30 mL/min/1.73 m(2), 27% in 1995; 58% in 2000; >or=60 mL/min/1.73 m(2): 25% in 1995; 49% in 2000). However, less than one third of all patients were treated with both disease-modifying therapies in 2000.

LIMITATIONS

We were unable to classify patients into those with systolic versus diastolic HF.

CONCLUSIONS

Our results suggest that use of disease-modifying therapies for patients hospitalized with clinical findings of acute HF and decreased kidney function remains less than desirable. Educational programs are needed to enhance the management of patients with decreased kidney function who develop HF.

Anaemia in heart failure: a common interaction with renal insufficiency called the cardio-renal anaemia syndrome

BACKGROUND

Although many studies have found a high prevalence of anaemia in patients with congestive heart failure (CHF), few have carefully examined the relationship between the CHF and the prevalence of anaemia and chronic renal insufficiency (CRI). Patients with advanced renal failure, significant anaemia, diffuse atherosclerosis, respiratory disease and more elderly patients have been systematically excluded from the great majority of the randomised clinical trials.

DISCUSSION

Both anaemia and renal insufficiency are very common associated diseases associated with increased mortality, morbidity and rate of hospitalisation in CHF patients. Impaired renal function is associated with adverse outcomes because it represents a marker of coexistent disease and more diffuse atherosclerosis. In patients with CHF, progressive renal dysfunction leads to a decrease in erythropoietin (EPO) levels with reduced erythrocyte production from bone marrow. This may explain the common association between CHF, anaemia and CRI in clinical practice. The normalisation of haemoglobin concentration by EPO in patients with CHF and CRI results in improved exercise capacity by increasing oxygen delivery and improving cardiac function.

CONCLUSION

In this review, we describe the mechanisms linking anaemic status, CRI and CHF, the prognostic relevance of each disease, treatment implications, and potential benefit of EPO administration.

Effect of carvedilol and metoprolol on the mode of death in patients with heart failure

BACKGROUND

In the COMET study, carvedilol improved survival compared to metoprolol tartrate in 3029 patients with NYHA II-IV heart failure and EF <35%, followed for an average of 58 months.

AIMS

To evaluate whether the effect on overall mortality was specific for a particular mode of death. This may help to identify the mechanism of the observed difference.

METHODS

Of the 1112 total deaths, 972 were adjudicated as cardiovascular, including 480 sudden, 365 circulatory failure (CF) and 51 stroke deaths. For each mode of death, the effect of pre-specified baseline variables was assessed, including sex, age, NYHA class, aetiology, heart rate, systolic blood pressure, EF, atrial fibrillation, previous myocardial infarction or hypertension, renal function, concomitant medication, and study treatment allocation.

RESULTS

In multivariate Cox regression analyses, compared to metoprolol, carvedilol reduced cardiovascular (RR 0.80, CI 0.7-0.91, p=0.0009), sudden (RR 0.77, CI 0.64-0.93, p=0.0073) and stroke deaths (RR 0.37, CI 0.19-0.71, p=0.0027) with a non-significant trend for CF death (RR 0.83, CI 0.66-1.04, p=0.07). Treatment benefit with carvedilol did not differ between modes of death, except for a greater reduction in stroke death with carvedilol (competing risk analysis, p=0.0071 vs CF death). There were no interactions between treatment allocation and baseline characteristics.

CONCLUSION

Mortality reduction with carvedilol compared to metoprolol appears relatively non-specific and could be consistent with a superior effect of carvedilol on cardiac function, arrhythmias or, in view of the greater reduction in stroke deaths, on vascular events.

The early anti-oxidant effect of carvedilol predicts the clinical course in congestive heart failure patients

BACKGROUND

Carvedilol, a beta1 and beta2 as well as an alpha1 adrenoreceptor antagonist with multiple hemodynamic, anti-ischemic and anti-oxidant properties, is widely accepted for the treatment of hypertension and congestive heart failure (CHF). It has been shown to improve morbidity and mortality in CHF.

OBJECTIVES

To assess whether the anti-oxidant effect of carvedilol has an impact on the clinical course in post-myocardial infarction (MI) CHF.

METHODS

Thirty-nine recent MI patients, aged 60.5 +/- 7 years, New York Heart Association functional class (FC) II-III, and left ventricular ejection fraction (LVEF) 29 +/- 3.8%, underwent oxygen free radical (OFR) assessment using the thiobarbituric acid reactive substances, thermochemoluminescence and conjugated dienes methods. OFR was determined at baseline, 1, 3, 12, and 24 h after 3.125, 6.25 and 12.5 mg carvedilol, and after 6 months of treatment. Brain natriuretic peptide (BNP), LVEF, FC change, 6-min walk test (6MW) and quality of life scores were evaluated before and after 6 months.

RESULTS

Two patterns of OFR activity were found. In 29 patients (group 1) a significant and consistent reduction in OFR following administration of each dose of carvedilol was found, significantly correlating with each of the outcome parameters. In ten patients (group 2), no change in OFR was found, nor in any of the other outcomes. At 6 months, FC improved in 23 patients from group 1 (79.3%) and only in one (10%) from group 2 (P<0.01). 6MW increased by more than 10% in group 1 with no change in group 2 (P<0.05). BNP decreased from 397 +/- 36 pg/ml to 171 +/- 15.9 pg/ml (P<0.01) in group 1 compared to 381 +/- 32.5 pg/ml and 405 +/- 36 pg/ml, respectively (P=not significant) in group 2. One year hospital admissions and death rate were significantly higher in group 2.

CONCLUSIONS

The early anti-oxidative effect of carvedilol correlates well with the clinical course and probably predicts it.

Beta-Blocker Treatment of Chronic Heart Failure: Comparison of Carvedilol and Metoprolol

Beta blockers have been shown to prolong survival in chronic heart failure. It is currently a matter of debate whether any beta blocker is superior to the other in terms of improving symptoms, left ventricular function, or prognosis. A number of comparative studies have been performed with metoprolol, a beta1-selective second-generation beta blocker, and carvedilol, a nonselective and vasodilatative third-generation beta blocker. This review will focus on the different pharmacological profiles of carvedilol and metoprolol as well as on the clinical consequences derived from these differences. The results indicate that in some studies carvedilol is superior to metoprolol in improving left ventricular ejection fraction. However, because there is no conclusive evidence that carvedilol is superior to metoprolol in terms of prognosis, it is not justified to substitute metoprolol with carvedilol. Comparative data on mortality reduction are not available before termination of the Carvedilol or Metoprolol European Trial. Nevertheless, the different effects of both beta blockers on the beta-adrenergic system have an impact on tolerability and beta-adrenergic responsiveness and thus exercise tolerance in heart-failure patients.

Synergistic polymorphisms of beta1 and alpha2C-adrenergic receptors and the influence on left ventricular ejection fraction response to beta-blocker therapy in heart failure

OBJECTIVES

The Arg389Gly polymorphism (Arg389Gly) in the beta1-adrenergic receptor gene (ADRB1) has been associated with improvement in left-ventricular remodeling with beta-blocker treatment. One study of risk for heart failure suggested a synergistic effect of ADRB1 Arg389Gly with the insertion/deletion polymorphism in the alpha2C-adrenergic receptor gene (ADRA2C). We tested whether the ADRA2C insertion/deletion polymorphism was associated with beta-blocker response in heart failure, either alone or in combination with the ADRB1Arg389Gly polymorphism.

METHODS

Fifty-four beta-blocker naive heart failure patients underwent echocardiography before and after 5-6 months of metoprolol CR/XL therapy. Multivariant linear regression modeling was performed to assess the impact of genotypes and other variables on changes in left-ventricular function in response to metoprolol therapy.

RESULTS

Deletion carriers had a significantly greater negative chronotropic response. Predictors of the end of study ejection fraction were baseline ejection fraction, deletion carrier status and Arg389Arg genotype. Patients with Arg389Arg/Del-carrier status showed the greatest ejection fraction increase with metoprolol CR/XL. Adjusting for baseline ejection fraction, final S-metoprolol plasma concentration and race, final ejection fraction in patients with this genotype combination was significantly higher than all other genotype combination groups.

CONCLUSION

ADRB1 and ADRA2C polymorphisms synergistically influence the ejection fraction response to beta-blocker therapy of heart failure patients.

Effect of β-Blockers on β3-Adrenoceptor Expression in Chronic Heart Failure

OBJECTIVES

To investigate the expression of beta(3)-adrenoceptors in rats with chronic heart failure, and to explore the effect of beta-blockers on beta(3)-adrenoceptor expression.

MATERIALS AND METHODS

Thirty-two male Wistar rats were divided into Sham (n = 10) and heart failure (n = 22) groups. The heart failure group was treated with normal saline (Heart Failure Control, n = 6), Metoprolol (n = 8) or Carvedilol (n = 8) for 3 months.

RESULTS

The left ventricular end systolic pressure (LVESP) and the absolute values of maximal rate of rise and fall of left ventricular pressure (+/-dP/dt max) in the heart failure group were lower than in the Sham group (P < 0.01), whereas the left ventricular end diastolic pressure (LVEDP) was higher (P < 0.01). The LVESP and dP/dtmax in the Carvedilol group were higher than the Metoprolol group whereas LVEDP was lower (P < 0.01). The left ventricular mass index (LVMI) in the Carvedilol group was less than the Metoprolol and Heart Failure Control groups (P < 0.01). The level of beta(3)-adrenoceptor expression in the study groups was significantly higher than the Sham group (P < 0.01). beta(3)-adrenoceptor expression in the Carvedilol group was lower than the Heart Failure Control and Metoprolol groups (P < 0.01).

CONCLUSION

beta(3)-adrenoceptor expression is increased in the failing ventricles in rats. Carvedilol is more effective than Metoprolol for improving the hemodynamics and in attenuating ventricular remodeling after heart failure. Carvedilol, rather than Metoprolol, diminishes beta(3)-adrenoceptor expression in the failing ventricles.

Prognostic importance of pulmonary hypertension in patients with heart failure

Pulmonary hypertension is a well-known complication in heart failure, but its prognostic importance is less well established. This study assessed the risk associated with pulmonary hypertension in patients with heart failure with preserved or reduced left ventricular (LV) ejection fractions. Patients with known or presumed heart failure (n = 388) underwent the echocardiographic assessment of pulmonary systolic pressure and LV ejection fraction. Patients were followed for up to 5.5 years. Increased pulmonary pressure was associated with increased short- and long-term mortality (p <0.0001 and p = 0.003, respectively). This relation was also present when stratifying patients by reduced or preserved LV function. A Cox proportional-hazards model apportioned a 9% increase in mortality per 5 mm Hg increase in right ventricular systolic pressure (p = 0.0008), independent of age and known chronic obstructive lung disease, heart failure, and impaired renal function. In conclusion, pulmonary hypertension is associated with increased short- and long-term mortality in patients with reduced LV ejection fractions and also in patients with preserved LV ejection fractions.

Chronic treatment with carvedilol improves Ca(2+)-dependent ATP consumption in triton X-skinned fiber preparations of human myocardium

Evidence is given that beta-blocker treatment differentially influences gene expression and up-regulation of beta(1)-adrenoceptors in human myocardium. Here, we investigate whether long-term treatment with carvedilol or metoprolol may functionally alter myofibrillar function in end-stage human heart failure. Investigations were performed in Triton X (1%, 4 degrees C, 20 h)-skinned fiber preparations of explanted hearts from patients undergoing heart transplantation due to idiopathic dilative cardiomyopathy. Five patients were not on beta-adrenoceptor blocker treatment (DCM_NBB), and 5 patients received either carvedilol (DCM_CAR) or metoprolol (DCM_MET). Nonfailing (NF) donor hearts (n = 5), which could not be transplanted due to technical reasons, were investigated for comparison. Ca(2+)-dependent tension (DT) development and actomyosin-ATPase activity (MYO) were measured and tension-dependent ATP consumption was calculated by the ratio of DT and MYO ("tension cost"). In addition, we measured the phosphorylation of troponin I (TNI) by back phosphorylation. Maximal DT and TNI phosphorylation were reduced, with myofibrillar Ca(2+) sensitivity of DT and MYO as well as tension cost being increased in DCM_NBB compared with NF. Metoprolol treatment restored TNI phosphorylation, decreased Ca(2+) sensitivity of tension development and of myosin-ATPase activity, but did not alter the tension-dependent ATP consumption. Carvedilol treatment improved maximal DT and significantly decreased tension-dependent ATP consumption without altering myofibrillar Ca(2+) sensitivity. TNI dephosphorylation was increased in patients treated with carvedilol. In conclusion, chronic beta-adrenoceptor blockade functionally alters myofibrillar function. The more economic cross-bridge cycling in patients under carvedilol treatment may provide an explanation for the efficacy of carvedilol in the treatment of chronic heart failure patients.

Renal dysfunction in heart failure patients: what is the evidence?

Congestive heart failure (CHF) is an increasingly common medical condition and the fastest growing cardiovascular diagnosis in North America. Over one-third of patients with heart failure also have renal insufficiency. It has been shown that renal insufficiency confers worsened outcomes to patients with heart failure. However, a majority of the larger and therapy-defining heart failure medication and device trials exclude patients with advanced renal dysfunction. These studies also infrequently perform subgroup analyses based on the degree of renal dysfunction. The lack of information on heart failure patients who have renal insufficiency likely contributes to their being prescribed mortality and morbidity reducing medications and receiving diagnostic and therapeutic procedures at lower rates than heart failure patients with normal renal function. Inclusion of patients with renal insufficiency in heart failure studies and published guidelines for medication, device, and interventional therapies would likely improve patient outcomes.

Carvedilol Protects Better Against Vascular Events Than Metoprolol in Heart Failure

OBJECTIVES

We explored whether vascular protection by carvedilol could contribute to its superior effects in the treatment of heart failure (HF) compared with metoprolol tartrate in the COMET (Carvedilol Or Metoprolol European Trial) study.

BACKGROUND

Full adrenergic blockade by carvedilol and additional (e.g., antioxidative) properties may lead to vascular protection relative to beta-1 blockade alone, and contribute to its efficacy in HF treatment.

METHODS

Three thousand twenty-nine patients with HF due to ischemic (51%) or idiopathic cardiomyopathy (44%) were randomized double-blind to carvedilol (n = 1,511) or metoprolol (n = 1,518) and followed for 58 months. Vascular end points were cardiovascular death, stroke, stroke death, myocardial infarction (MI), and unstable angina.

RESULTS

The effect of carvedilol on cardiovascular death improved consistently in subgroups with prespecified baseline variables. Myocardial infarctions were reported in 69 carvedilol and 94 metoprolol patients (hazard ratio [HR] 0.71, 95% confidence interval [CI] 0.52 to 0.97, p = 0.03). Cardiovascular death or nonfatal MI combined were reduced by 19% in carvedilol (HR 0.81, 95% CI 0.72 to 0.92, p = 0.0009 vs. metoprolol). Unstable angina was reported as an adverse event in 56 carvedilol and in 77 metoprolol patients (HR 0.71, 95% CI 0.501 to 0.998, p = 0.049). A stroke occurred in 65 carvedilol and 80 metoprolol patients (HR 0.79, 95% CI 0.57 to 1.10). Stroke or MI combined occurred in 130 carvedilol and 168 metoprolol patients (HR 0.75, 95% CI 0.60 to 0.95, p = 0.015), and fatal MI or fatal stroke occurred in 34 carvedilol and in 72 metoprolol patients (HR 0.46, 95% CI 0.31 to 0.69, p = 0.0002). Death after a nonfatal MI or stroke occurred in 61 of 124 carvedilol and in 106 of 160 metoprolol patients (HR 0.66, 95% CI 0.48 to 0.90, p = 0.0086).

CONCLUSIONS

Carvedilol improves vascular outcomes better than metoprolol. These results suggest a ubiquitous protective effect of carvedilol against major vascular events.