Pharmacological treatment of vascular risk factors for reducing mortality and cardiovascular events in patients with abdominal aortic aneurysm

BACKGROUND

Pharmacological prophylaxis has been proven to reduce the risk of cardiovascular events in individuals with atherosclerotic occlusive arterial disease. However, the role of prophylaxis in individuals with abdominal aortic aneurysm (AAA) remains unclear. Several studies have shown that despite successful repair, those people with AAA have a poorer rate of survival than healthy controls. People with AAA have an increased prevalence of coronary heart disease and risk of cardiovascular events. Despite this association, little is known about the effectiveness of pharmacological prophylaxis in reducing cardiovascular risk in people with AAA. This is an update of a Cochrane review first published in 2014.

OBJECTIVES

To determine the long-term effectiveness of antiplatelet, antihypertensive or lipid-lowering medication in reducing mortality and cardiovascular events in people with abdominal aortic aneurysm (AAA).

SEARCH METHODS

For this update the Cochrane Vascular Information Specialist (CIS) searched the Cochrane Vascular Specialised Register (14 April 2016). In addition, the CIS searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 3) and trials registries (14 April 2016) and We also searched the reference lists of relevant articles.

SELECTION CRITERIA

Randomised controlled trials in which people with AAA were randomly allocated to one prophylactic treatment versus another, a different regimen of the same treatment, a placebo, or no treatment were eligible for inclusion in this review. Primary outcomes included all-cause mortality and cardiovascular mortality.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, and completed quality assessment and data extraction. We resolved any disagreements by discussion. Only one study met the inclusion criteria of the review, therefore we were unable to perform meta-analysis.

MAIN RESULTS

No new studies met the inclusion criteria for this update. We included one randomised controlled trial in the review. A subgroup of 227 participants with AAA received either metoprolol (N = 111) or placebo (N = 116). There was no clear evidence that metoprolol reduced all-cause mortality (odds ratio (OR) 0.17, 95% confidence interval (CI) 0.02 to 1.41), cardiovascular death (OR 0.20, 95% CI 0.02 to 1.76), AAA-related death (OR 1.05, 95% CI 0.06 to 16.92) or increased nonfatal cardiovascular events (OR 1.44, 95% CI 0.58 to 3.57) 30 days postoperatively. Furthermore, at six months postoperatively, estimated effects were compatible with benefit and harm for all-cause mortality (OR 0.71, 95% CI 0.26 to 1.95), cardiovascular death (OR 0.73, 95% CI 0.23 to 2.39) and nonfatal cardiovascular events (OR 1.41, 95% CI 0.59 to 3.35). Adverse drug effects were reported for the whole study population and were not available for the subgroup of participants with AAA. We considered the study to be at a generally low risk of bias. We downgraded the quality of the evidence for all outcomes to low. We downgraded the quality of evidence for imprecision as only one study with a small number of participants was available, the number of events was small and the result was consistent with benefit and harm.

AUTHORS' CONCLUSIONS

Due to the limited number of included trials, there is insufficient evidence to draw any conclusions about the effectiveness of cardiovascular prophylaxis in reducing mortality and cardiovascular events in people with AAA. Further good-quality randomised controlled trials that examine many types of prophylaxis with long-term follow-up are required before firm conclusions can be made.

Impact of Beta-Blocker Initiation Timing on Mortality Risk in Patients With Diabetes Mellitus Undergoing Noncardiac Surgery: A Nationwide Population-Based Cohort Study

BACKGROUND

Relevant clinical studies have been small and have not convincingly demonstrated whether the perioperative initiation of beta-blockers should be considered in patients with diabetes mellitus undergoing noncardiac surgery.

METHODS AND RESULTS

In this nationwide propensity score-matched study, we included patients with diabetes mellitus undergoing noncardiac surgery between 2000 and 2011 from Taiwan's National Health Insurance Research Database. Patients were classified as beta-blocker and non-beta-blocker cohorts. We further stratified beta-blocker users into cardioprotective beta-blocker (atenolol, bisoprolol, metoprolol, or carvedilol) and other beta-blocker users. To investigate time of initiation of beta-blocker use, initiation time was stratified into 2 periods (>30 and ≤30 days preoperatively). The outcomes of interest were in-hospital and 30-day mortality. After propensity score matching, we identified 50 952 beta-blocker users and 50 952 matched controls. Compared with non-beta-blocker users, cardioprotective beta-blocker users were associated with lower risks of in-hospital (odds ratio 0.75, 95% CI 0.68-0.82) and 30-day (odds ratio 0.75, 95% CI 0.70-0.81) mortality. Among initiation times, only the use of cardioprotective beta-blockers for >30 days was associated with decreased risk of in-hospital (odds ratio 0.72, 95% CI 0.65-0.78) and 30-day (odds ratio 0.72, 95% CI 0.66-0.78) mortality. Of note, use of other beta-blockers for ≤30 days before surgery was associated with increased risk of both in-hospital and 30-day mortality.

CONCLUSIONS

The use of cardioprotective beta-blockers for >30 days before surgery was associated with reduced mortality risk, whereas short-term use of beta-blockers was not associated with differences in mortality in patients with diabetes mellitus.

Evaluating the effectiveness of different beta-adrenoceptor blockers in heart failure patients

BACKGROUND

According to guidelines and pivotal trials, β-blockers are associated with better survival in patients with heart failure (HF). However, the superiority of any β-blockers is still unclear.

METHODS

This retrospective cohort study was conducted using the National Health Insurance Research Database in Taiwan to evaluate the effectiveness of β-blockers and compare the clinical outcomes of different β-blockers in patients with HF. We enrolled patients diagnosed with HF between 2005 and 2012. We then stratified the β-blockers according to the starting dose: lower in group 1 and higher in group 2. A time-dependent Cox proportional hazards regression model was applied to evaluate the effectiveness of the β-blockers.

RESULTS

A total of 14,875 patients with HF were identified during the study period. After propensity-score matching, 5688 patients were included in both the β-blocker user and nonuser groups. We found that group 2 carvedilol and group 2 bisoprolol significantly reduced the risk of death and hospitalization for HF, whereas metoprolol did not. Compared with group 2 carvedilol, survival was not significantly different for group 2 bisoprolol (adjusted hazard ratio=1.18, 95% confidence interval=0.88-1.58).

CONCLUSION

From results, carvedilol and bisoprolol were associated with better outcomes, with no difference between these two β-blockers in patients with HF in Taiwan.

Drug and Drug-Device Therapy in Heart Failure Patients in the Post-COMET and SCD-HeFT Era

Reduced left ventricular ejection fraction and heart failure are the most important risk factors for sudden cardiac death. Recent trials have contributed to the knowledge base of critical therapies for the treatment of left ventricular systolic dysfunction and heart failure as it relates to arrhythmic and sudden cardiac death. Both pharmacologic and device therapies can reduce sudden cardiac death. The trials discussed in this paper have identified the pharmacologic and device interventions that are likely to improve the length and quality of life of the patient with left ventricular dysfunction and reduce the risk of sudden cardiac death. The mortality and anti-arrhythmic effects of angiotensin-converting enzyme inhibitors and β-blockers have been confirmed in large-scale controlled clinical heart failure trials. Recent trials have evaluated which agents are most effective and which patients will derive the most benefit from device therapy in terms of the reduction in the risk of sudden cardiac death and in the amelioration of heart failure. The recent data from the Carvedilol or Metoprolol European Trial (COMET) and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) are discussed as the latest in the series of landmark studies that have shaped the current approaches to treating patients with heart failure and that have altered the heart failure treatment paradigm.

A Review of Carvedilol Arrhythmia Data in Clinical Trials

β-Blockers are currently being evaluated more intensively to define their role in clinical use as antiarrhythmic agents. β-Adrenergic blockade has been studied in relation to atrial fibrillation, ventricular arrhythmias, and sudden death; however, it is apparent from a number of studies that not all β-blockers are equally effective. Randomized clinical trial data, both in heart failure and post-myocardial infarction (MI) patients, have shown differences in mortality benefits in addition to a variable effect on arrhythmias and sudden death. Carvedilol, a third-generation β-blocker with proven clinical benefit in the management of heart failure and post-MI patients, has properties that may make it an effective antiarrhythmic agent. This paper reviews the current clinical arrhythmia data available for carvedilol from large-scale clinical trials and small studies. The trial evidence demonstrates that carvedilol therapy can be an effective adjunctive rate-control therapy in patients with atrial fibrillation, prevent mortality in patients with heart failure or post-MI with left ventricular dysfunction, with or without atrial fibrillation, and reduce its onset and the incidence of ventricular arrhythmia and sudden death.

[Comparative Assessment of Antianginal Efficacy and Safety of Nicorandil at the Background of Therapy With -Adrenoblockers in Ischemic Heart Disease Patients With Stable Angina]

AIM

to demonstrate impact of addition of nicorandil to standard treatment in patients with stable ischemic heart disease (IHD) on clinical manifestations of the disease and safety of conducted therapy.

MATERIAL AND METHODS

We included in this double-blind placebo controlled study with parallel groups 120 patients with verified IHD and stable effort angina. During the entire study all patients received metoprolol (100 mg/day). Patients of main group were given nicorandil (10 mg twice a day for 2 weeks and 20 mg twice a day thereafter); patients of control group were given placebo. Study duration was 6 weeks.

RESULTS

Addition of nicorandil was associated with significant reduction of number of anginal attacks both compared with control period and addition of placebo. Consumption of short acting nitrates significantly decreased on both nicorandil doses compared with control period. Adverse events were registered in 10 of 61 and 7 of 59 patients (16.4 and 11.9%) taking nicorandil and placebo, respectively (n.s.). Three patients withdrew from the study because of headache.

CONCLUSION

Addition of nicorandil to standard therapy in patients with chronic IHD and stable effort angina promoted significant reduction of number of angina attacks. Good tolerability of nicorandil was also demonstrated.

Comparison of Pyrroloquinoline Quinone and/or Metoprolol on Myocardial Infarct Size and Mitochondrial Damage in a Rat Model of Ischemia/Reperfusion Injury

The cardioprotective effectiveness of low-dose pyrroloquinoline quinone (PQQ, 3 mg/kg) was compared with metoprolol, a β1-selective adrenoceptor antagonist. Rats underwent 30 minutes of left anterior descending coronary artery occlusion and 2 hours of reperfusion. Metoprolol and/or PQQ were given at the onset of reperfusion to mimic clinical treatment. Metoprolol and/or PQQ reduced infarct size and protected against ischemia-induced left ventricular dysfunction after 2 hours of reper-fusion. Combined therapy augmented left ventricular developed pressure at the end of reperfusion. Metoprolol or PQQ alone enhanced mitochondrial respiratory ratios in ischemic and nonischemic myocardium. Although the PQQ/metoprolol combination therapy increased respiratory ratio values, the effects were small when compared with PQQ alone. Only PQQ decreased lipid peroxidation. Metoprolol and/or PQQ given at the onset of reperfusion reduce infarct size and improve cardiac function. Combination therapy further reduces infarct size. PQQ is superior to metoprolol in protecting mitochondria from ischemia/reperfusion oxidative damage

Carvedilol Improves Myocardial Contractility Compared With Metoprolol in Patients With Chronic Hibernating Myocardium After Revascularization

Background: We tested the hypothesis of whether carvedilol delays morphologic degeneration and improves functional outcome compared with metoprolol tartrate in patients with hibernating myocardium undergoing surgical revascularization. We have previously shown that patients with chronic hibernating myocardium undergo progressive cellular degeneration and fibrosis.

Methods: Twenty patients with multivessel coronary artery disease revascularization and hibernating myocardium as assessed by technetium-99m perfusion scintigraphy and fluorine-18-fluorodeoxyglucose positron emission tomography were randomized to receive either carvedilol or metoprolol tartrate for at least 2 months before surgery, and this was continued for 7 months postoperatively. Left ventricular ejection fraction and regional wall motion abnormalities were assessed by left ventriculography at baseline and 7 months postoperatively. Intraoperative transmural needle biopsy samples were obtained for microscopic analysis.

Results: Postoperatively, the ejection fraction increased from 31% ± 5% to 44% ± 4% ( P < .005) in the carvedilol group (n = 10), and from 30% ± 6% to 40% ± 6% in the metoprolol tartrate group ( P < .05 vs preoperatively and vs carvedilol). Wall motion abnormalities in the carvedilol group improved from -2.1 ± 0.4 to -0.6 ± 0.5 ( P < .05) and from -2.3 ± 0.5 to -1.6 ± 0.6 in the metoprolol tartrate group ( P < .05 vs preoperatively and vs carvedilol). Microscopic analysis after 72 ± 18 days of either treatment showed mild cardiomyocyte degeneration and moderate-to-severe fibrosis (28% ± 7%) in the carvedilol group compared with moderate cardiomyocyte degeneration and moderate-to-severe fibrosis (33% ± 6%) in the metoprolol tartrate group. Apoptosis, as assessed by the terminal deoxynucleotidyl transferase nick end labeling method, was observed in only 1 patient in each group.

Conclusions: Carvedilol treatment of hibernating myocardium results in improved functional recovery after revascularization compared with metoprolol tartrate, and this might partially be related to reduced cardiomyocyte degeneration.

Pharmacodynamics ofβ-Blockers in Heart Failure: Lessons from the Carvedilol Or Metoprolol European Trial

Heart failure is a growing public health problem in the United States, and the approach to the treatment of heart failure has undergone a radical transformation in the past decade. The use of β-blocker therapy in heart failure patients is now widely recommended, based on evidence from large-scale clinical trials demonstrating that bisoprolol, carvedilol, and extended-release metoprolol succinate significantly reduce morbidity and mortality in patients with heart failure. Although these agents appear to provide similar benefits, the question remains whether pharmacologic differences among them could translate to differences in clinical outcomes. The Carvedilol Or Metoprolol European Trial (COMET) compared nonselective blockade of the β1-/β2-/α1-adrenergic receptors with carvedilol versus selective β1-blockade with immediate-release metoprolol tartrate in patients with chronic heart failure. The trial found that carvedilol significantly reduced all-cause mortality compared with immediate-release metoprolol tartrate, although there were no differences in hospitalizations. Herein we review the pharmacokinetics and pharmacodynamics of metoprolol and carvedilol. In doing so, several issues regarding the design of COMET are identified that could alter the interpretation of the results of this trial. These include the choice of dose and dosage regimen of immediate-release metoprolol tartrate, a dosage form that has never been shown to reduce mortality in patients with heart failure. Additional studies are needed to fully understand whether there are any advantages of selective versus nonselective adrenergic blockade and whether there are any clinically meaningful differences in effectiveness between β-blockers with proven benefit in the management of chronic heart failure. The results of COMET demonstrate that all β-blockers and dosage forms are not interchangeable when prescribed for heart failure. Clinicians should choose only those agents (and dosage forms) that have been proven to reduce mortality in this patient population.

β-Blockers for the prevention of acute exacerbations of chronic obstructive pulmonary disease (βLOCK COPD): a randomised controlled study protocol

INTRODUCTION

A substantial majority of chronic obstructive pulmonary disease (COPD)-related morbidity, mortality and healthcare costs are due to acute exacerbations, but existing medications have only a modest effect on reducing their frequency, even when used in combination. Observational studies suggest β-blockers may reduce the risk of COPD exacerbations; thus, we will conduct a randomised, placebo-controlled trial to definitively assess the impact of metoprolol succinate on the rate of COPD exacerbations.

METHODS AND ANALYSES

This is a multicentre, placebo-controlled, double-blind, prospective randomised trial that will enrol 1028 patients with at least moderately severe COPD over a 3-year period. Participants with at least moderate COPD will be randomised in a 1:1 fashion to receive metoprolol or placebo; the cohort will be enriched for patients at high risk for exacerbations. Patients will be screened and then randomised over a 2-week period and will then undergo a dose titration period for the following 6 weeks. Thereafter, patients will be followed for 42 additional weeks on their target dose of metoprolol or placebo followed by a 4-week washout period. The primary end point is time to first occurrence of an acute exacerbation during the treatment period. Secondary end points include rates and severity of COPD exacerbations; rate of major cardiovascular events; all-cause mortality; lung function (forced expiratory volume in 1 s (FEV1)); dyspnoea; quality of life; exercise capacity; markers of cardiac stretch (pro-NT brain natriuretic peptide) and systemic inflammation (high-sensitivity C reactive protein and fibrinogen). Analyses will be performed on an intent-to-treat basis.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Department of Defense Human Protection Research Office and will be approved by the institutional review board of all participating centres. Study findings will be disseminated through presentations at national and international conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02587351; Pre-results.

Carvedilol, Bisoprolol, and Metoprolol Use in Patients With Coexistent Heart Failure and Chronic Obstructive Pulmonary Disease

Beta (β)-blockers are under-prescribed in patients with heart failure (HF) and concurrent chronic obstructive pulmonary disease (COPD) due to concerns about adverse pulmonary effects and a poor understanding of the effects of these drugs. We aimed to evaluate the survival effects of β-blockers in patients with coexistent HF and COPD. Using the Taiwan National Health Insurance Research Database, we conducted a nationwide population-based study. Patients with coexistent HF and COPD diagnosed between 2000 and 2009 were enrolled. Doses of the 3 β-blockers proven to be beneficial to HF (carvedilol, bisoprolol, and metoprolol) during the study period were extracted. The primary endpoint was cumulative survival. Patients were followed until December 31, 2009. The study included 11,558 subjects, with a mean follow-up period of 4.07 years. After adjustment for age, sex, comorbidities, and severity of HF and COPD, bisoprolol use showed a dose-response survival benefit [low dose: adjusted hazard ratio (HR) = 0.76, 95% confidence interval (CI) = 0.59-0.97, P = 0.030; high dose: adjusted HR = 0.40, 95% CI = 0.26-0.63, P < 0.001] compared with nonusers, whereas no survival difference was observed for carvedilol or metoprolol. Compared with patients with HF alone, this special HF + COPD cohort received significantly fewer targeted β-blockers (108.8 vs 137.3 defined daily doses (DDDs)/person-year, P < 0.001) and bisoprolol (57.9 vs 70.8 DDDs/person-year, P < 0.001). In patients with coexisting HF and COPD, this study demonstrated a dose-response survival benefit of bisoprolol use, but not of carvedilol or metoprolol use.

Beta-blockers for congestive heart failure in children

BACKGROUND

Beta-blockers are an essential part of standard therapy in adult congestive heart failure and therefore, are expected to be beneficial in children. However, congestive heart failure in children differs from that in adults in terms of characteristics, aetiology, and drug clearance. Therefore, paediatric needs must be specifically investigated. This is an update of a Cochrane review previously published in 2009.

OBJECTIVES

To assess the effect of beta-adrenoceptor-blockers (beta-blockers) in children with congestive heart failure.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and LILACS up to November 2015. Bibliographies of identified studies were checked. No language restrictions were applied.

SELECTION CRITERIA

Randomised, controlled, clinical trials investigating the effect of beta-blocker therapy on paediatric congestive heart failure.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted and assessed data from the included trials.

MAIN RESULTS

We identified four new studies for the review update; the review now includes seven studies with 420 participants. Four small studies with 20 to 30 children each, and two larger studies of 80 children each, showed an improvement of congestive heart failure with beta-blocker therapy. A larger study with 161 participants showed no evidence of benefit over placebo in a composite measure of heart failure outcomes. The included studies showed no significant difference in mortality or heart transplantation rates between the beta-blocker and control groups. No significant adverse events were reported with beta-blockers, apart from one episode of complete heart block. A meta-analysis of left ventricular ejection fraction (LVEF) and fractional shortening (LVFS) data showed a very small improvement with beta-blockers.However, there were vast differences in the age, age range, and health of the participants (aetiology and severity of heart failure; heterogeneity of diagnoses and co-morbidities); there was a range of treatments across studies (choice of beta-blocker, dosing, duration of treatment); and a lack of standardised methods and outcome measures. Therefore, the primary outcomes could not be pooled in meta-analyses.

AUTHORS' CONCLUSIONS

There is not enough evidence to support or discourage the use of beta-blockers in children with congestive heart failure, or to propose a paediatric dosing scheme. However, the sparse data available suggested that children with congestive heart failure might benefit from beta-blocker treatment. Further investigations in clearly defined populations with standardised methodology are required to establish guidelines for therapy. Pharmacokinetic investigations of beta-blockers in children are also required to provide effective dosing in future trials.

Nebivolol versus Carvedilol or Metoprolol in Patients Presenting with Acute Myocardial Infarction Complicated by Left Ventricular Dysfunction

OBJECTIVE

The aim of this study was to evaluate the efficacy of nebivolol, carvedilol or metoprolol succinate on the outcome of patients presenting with acute myocardial infarction (AMI) complicated by left ventricular dysfunction.

SUBJECTS AND METHODS

Patients (n = 172, aged 28-87 years) with AMI and left ventricular ejection fraction ≤0.45 were randomized to the nebivolol (n = 55), carvedilol (n = 60) and metoprolol succinate (n = 57) groups. Baseline demographic and clinical characteristics and composite event rates of nonfatal MI, cardiovascular mortality, hospitalization due to unstable angina pectoris or heart failure, stroke or revascularization during the 12-month follow-up were compared among the groups using the x03C7;2 test, t test or log-rank test as appropriate.

RESULTS

Baseline demographic and clinical characteristics were similar in the three groups. The composite end point during follow-up was lower in the patients treated with nebivolol than those treated with metoprolol (14.5 vs. 31.5%; p = 0.03). However, event rates were similar between the patients treated with carvedilol and those treated with the metoprolol (20.3 vs. 31.5%, p > 0.05) and between the patients treated with nebivolol and carvedilol (14.5 vs. 20.3%, p > 0.05).

CONCLUSION

The patients treated with nebivolol experienced 12-month cardiovascular events at a lower rate than those treated with metoprolol succinate. However, event rates were similar between the carvedilol and the metoprolol succinate groups and between the nebivolol and the carvedilol groups.

Effects of beta-blockers for congestive heart failure in pediatric and congenital heart disease patients: a meta-analysis of published studies

AIM

The effects of beta-blockers in pediatric and congenital heart disease (CHD) patients suffering from heart failure are controversial. We performed a meta-analysis to determine whether beta-blockers are effective for heart failure in pediatric and CHD patients.

METHODS

We searched for clinical trials focusing on clinical on clinical and ventricular functional/dimensional changes after beta-blocker therapy in PubMed (from its inception to August 2013) and bibliographies of identified studies. Studies investigating any of three beta blockers (carvedilol, bisoprolol, and extended release metoprolol succinate) which are known to be effective in adult patients with heart failure were included.

RESULTS

Of the 158 screened, 17 (N.=476) fulfilled the study criteria and were analyzed. Beta-blockers were associated with significant improvements in left ventricular (LV) ejection fraction (EF) (12.47%; 95% CI, 10.36 to 14.61), fraction shortening (5.75%; 95% CI, 4.42 to 7.08), LV end-diastolic dimension (-2.91 mm; 95% CI, -5.46 to -0.36), and LV systolic dimension (-4.03 mm; 95% CI, -6.81 to -1.25). No significant change in the pooled mean difference of the right ventricular (RV) EF (3.50%; P=0.08) was observed. However, the RV EF in the untreated group showed a deteriorating trend (-3%), which was different from the trend in the treatment group. There was a significant reduction in the incidence of clinical worsening (odds ratio, 2.15; 95% CI, 1.27 to 3.66).

CONCLUSION

Beta-blocker therapy was associated with a significant improvement of echocardiographic parameters in patients with systemic LV failure. However, the use of beta-blockers did not provide significant benefits in terms of improving the EF in patients with RV failure. Nonetheless, beta-blockers may be effective to prevent the clinical deterioration of pediatric and CHD patients with heart failure.

Plasma C-type natriuretic peptide as a predictor for therapeutic response to metoprolol in children with postural tachycardia syndrome

POTS is a global public-health disease, but predictor for therapeutic response to metoprolol in children with POTS is lacking. This study was designed to investigate predictive value of plasma C-type natriuretic peptide (CNP) in the therapeutic efficacy of metoprolol on postural tachycardia syndrome (POTS) in children. Totally 34 children with POTS and 27 healthy children were included in the study. The head-up test or head-up tilt test was used to check heart rate and blood pressure from supine to upright in subjects. A double antibody (competitive) sandwich immunoluminometric assay was used to detect plasma CNP. Metoprolol was used to treat children with POTS. The difference in plasma concentrations of CNP between responders and non-responders was compared. An ROC curve was used to analyze plasma CNP to predict efficacy of metoprolol on POTS in children. Plasma CNP in children with POTS was significantly higher than that of healthy children [(51.9 ± 31.4) vs. (25.1 ± 19.1) pg/ml, P <0.001]. Plasma CNP in responders to metoprolol was significantly higher than non-responders [(59.1 ± 33.5) vs. (34.8 ± 16.7) pg/ml, P = 0.037] before treatment. The ROC curve showed that area under the curve was 0.821 (95% CI 0.642–0.999). The cut-off value of plasma CNP > 32.55 pg/ml yielded a sensitivity of 95.8% and specificity of 70% in predicting therapeutic efficacy of metoprolol on POTS children. Plasma CNP might serve as a useful predictor for the therapeutic efficacy of metoprolol on POTS in children.

Effects of lifestyle changes and high-dose β-blocker therapy on exercise capacity in children, adolescents, and young adults with hypertrophic cardiomyopathy

AIM

The use of β-blocker therapy in asymptomatic patients with hypertrophic cardiomyopathy is controversial. This study evaluates the effect of lifestyle changes and high-dose β-blocker therapy on their exercise capacity.

METHODS AND RESULTS

A total of 29 consecutive newly diagnosed asymptomatic patients with familial hypertrophic cardiomyopathy, median age 15 years (range 7-25), were recruited. In all, 16 patients with risk factors for sudden death were treated with propranolol if no contraindications, or equivalent doses of metoprolol; 13 with no risk factors were randomised to metoprolol or no active treatment. Thus, there were three treatment groups, non-selective β-blockade (n=10, propranolol 4.0-11.6 mg/kg/day), selective β-blockade (n=9, metoprolol 2.7-5.9 mg/kg/day), and randomised controls (n=10). All were given recommendations for lifestyle modifications, and reduced energetic exercise significantly (p=0.002). Before study entry, and after 1 year, all underwent bicycle exercise tests with a ramp protocol. There were no differences in exercise capacity between the groups at entry, or follow-up, when median exercise capacity in the groups were virtually identical (2.4, 2.3, and 2.3 watt/kg and 55, 55, and 55 watt/(height in metre) 2 in control, selective, and non-selective groups, respectively. Maximum heart rate decreased in the selective (-29%, p=0.04) and non-selective (-24%, p=0.002) groups. No patient developed a pathological blood-pressure response to exercise because of β-blocker therapy. Boys were more frequently risk-factor positive than girls (75% versus 33%, p=0.048) and had higher physical activity scores than girls at study-entry (p=0.011).

CONCLUSIONS

Neither selective nor non-selective β-blockade causes significant reductions in exercise capacity in patients with hypertrophic cardiomyopathy above that induced by lifestyle changes.

Beta-adrenergic blockers for perioperative cardiac risk reduction in people undergoing vascular surgery

BACKGROUND

People undergoing major vascular surgery have an increased risk of postoperative cardiac complications. Beta-adrenergic blockers represent an important and established pharmacological intervention in the prevention of cardiac complications in people with coronary artery disease. It has been proposed that this class of drugs may reduce the risk of perioperative cardiac complications in people undergoing major non-cardiac vascular surgery.

OBJECTIVES

To review the efficacy and safety of perioperative beta-adrenergic blockade in reducing cardiac or all-cause mortality, myocardial infarction, and other cardiovascular safety outcomes in people undergoing major non-cardiac vascular surgery.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (January 2014) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2013, Issue 12). We searched trials databases and checked reference lists of relevant articles.

SELECTION CRITERIA

We included prospective, randomised controlled trials of perioperative beta-adrenergic blockade of people over 18 years of age undergoing non-cardiac vascular surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection and data extraction. We resolved disagreements through discussion. We performed meta-analysis using a fixed-effect model with odds ratios (ORs) and 95% confidence intervals (CIs).

MAIN RESULTS

We included two studies in this review, both of which were double-blind, randomised controlled trials comparing perioperative beta-adrenergic blockade (metoprolol) with placebo, on cardiovascular outcomes in people undergoing major non-cardiac vascular surgery. We included 599 participants receiving beta-adrenergic blockers (301 participants) or placebo (298 participants). The overall quality of studies was good. However, one study did not report random sequence generation or allocation concealment techniques, indicating possible selection bias, and the other study did not report outcome assessor blinding and was possibly underpowered. It should be noted that several of the outcomes were only reported in a single study and neither of the studies reported on vascular patency/graft occlusion, which reduces the quality of evidence to moderate. There was no evidence that perioperative beta-adrenergic blockade reduced all-cause mortality (OR 0.62, 95% CI 0.03 to 15.02), cardiovascular mortality (OR 0.34, 95% CI 0.01 to 8.32), non-fatal myocardial infarction (OR 0.83, 95% CI 0.46 to 1.49; P value = 0.53), arrhythmia (OR 0.70, 95% CI 0.26 to 1.88), heart failure (OR 1.71, 95% CI 0.40 to 7.23), stroke (OR 2.67, 95% CI 0.11 to 67.08), composite cardiovascular events (OR 0.87, 95% CI 0.55 to 1.39; P value = 0.57) or re-hospitalisation at 30 days (OR 0.86, 95% CI 0.48 to 1.52). However, there was strong evidence that beta-adrenergic blockers increased the odds of intra-operative bradycardia (OR 4.97, 95% CI 3.22 to 7.65; P value < 0.00001) and intra-operative hypotension (OR 1.84, 95% CI 1.31 to 2.59; P value = 0.0005).

AUTHORS' CONCLUSIONS

This meta-analysis currently offers no clear evidence that perioperative beta-adrenergic blockade reduces postoperative cardiac morbidity and mortality in people undergoing major non-cardiac vascular surgery. There is evidence that intra-operative bradycardia and hypotension are more likely in people taking perioperative beta-adrenergic blockers, which should be weighed with any benefit.

[Hypertrophic cardiomyopathy with midventricular obstruction of the left ventricle (MVO)--case report]

A 76-year old woman with a history of stage 3 arterial hypertension, paroxysmal atrial fibrillation, hypercholesterolemia and type 2 diabetes mellitus. Ventricular tachycardia was the first clinical manifestation of the disease. Echocardiography revealed hypertrophic cardiomyopathy with a high intraventricular gradient of 47 mmHg and midventricular obstruction at the level of the papillary muscles (the lumen of the left ventricle was 1-2 mm during systole). No ventricular aneurysm was found but the ventricle was elongated and dilated in the periapical part where systolic function was decreased but synchronized in time. Coronary angiograms showed no narrowing of coronary arteries. A single-chamber cardioverter-defibrillator (ICD, implantable cardioverter-defibrillator) was implanted to prevent sudden cardiac death. Modified-release metoprolol and amiodarone were administered in antiarrhythmic therapy. This case represents a rare kind of hypertrophic cardiomyopathy in an elderly woman which is characterized by midventricular obstruction.

[Which is the preferred perioperative beta-blocker?]

Guidelines on perioperative cardiovascular evaluation and management of patients undergoing non-cardiac surgery recommend initiation of beta-blocker therapy in at-risk patients who are undergoing intermediate- to high-risk surgery. Continuation of therapy in patients already receiving beta-blockers is also recommended. Recent literature, however, reported an increased risk of perioperative cardiovascular mortality among patients who continued with existing beta-blockade; most patients in this study were using metoprolol. There are important pharmacodynamic and pharmacokinetic differences between various beta-blockers, and these differences may explain the differences in clinical effects. Metoprolol has less beta1 receptor affinity compared with atenolol and bisoprolol, and beta1 receptor polymorphisms affect the clinical effects of metoprolol. Furthermore, metoprolol is dependent on activity of the CYP2D6 liver enzyme, which results in clinically important differences in plasma concentration. It is, therefore, wise to follow the European guidelines and to initiate beta-blocker therapy in the perioperative period with either atenolol or bisoprolol.

Beta-blocker use in severe sepsis and septic shock: a systematic review

OBJECTIVE

Recent growing evidence suggests that beta-blocker treatment could improve cardiovascular dynamics and possibly the outcome of patients admitted to intensive care with severe sepsis or septic shock.

DESIGN

Systematic review.

DATA SOURCES

MEDLINE and EMBASE healthcare databases.

REVIEW METHODS

To investigate this topic, we conducted a systematic review of the above databases up to 31 May 2015. Due to the clinical novelty of the subject, we also included non-randomized clinical studies. We focused on the impact of beta-blocker treatment on mortality, also investigating its effects on cardiovascular, immune and metabolic function. Evidence from experimental studies was reviewed as well.

RESULTS

From the initial search we selected 10 relevant clinical studies. Five prospective studies (two randomized) assessed the hemodynamic effects of the beta1-blocker esmolol. Heart rate decreased significantly in all, but the impact on other parameters differed. The imbalance between prospective studies' size (10 to 144 patients) and the differences in their design disfavor a meta-analysis. One retrospective study showed improved hemodynamics combining metoprolol and milrinone in septic patients, and another retrospective study found no association between beta-blocker administration and mortality. We also found three case series. Twenty-one experimental studies evaluated the hemodynamic, immune and/or metabolic effects of selective and/or non-selective beta-blockers in animal models of sepsis (dogs, mice, pigs, rats, sheep), yielding conflicting results.

CONCLUSIONS

Whilst there is not enough prospective data to conduct a meta-analysis, the available clinical data are promising. We discuss the ability of beta blockade to modulate sepsis-induced alterations at cardiovascular, metabolic, immunologic and coagulation levels.

Addition of N-acetyl cysteine to carvedilol decreases the incidence of acute renal injury after cardiac surgery

BACKGROUND

Oxidative stress and inflammation during cardiac surgery may be associated with acute renal injury (ARI). N-acetyl cysteine (NAC) and carvedilol have antioxidant and anti-inflammatory properties.

HYPOTHESIS

A combination of carvedilol and NAC should decrease the incidence of ARI more than metoprolol or carvedilol.

METHODS

Patients undergoing cardiac surgery were randomized to metoprolol, carvedilol, or carvedilol plus NAC. End points were occurrence of ARI and change in preoperative to postoperative peak creatinine levels.

RESULTS

ARI incidence was lower in the carvedilol plus NAC group compared with the metoprolol (21.0% vs 42.1%; P = 0.002) or carvedilol (21.0% vs 38.6%; P = 0.006) groups, but was similar between the metoprolol and carvedilol groups (P = 0.62). Preoperative and postoperative day 1 creatinine levels were similar among the metoprolol (1.02 [0.9-1.2] and 1.2 [0.92-1.45]) the carvedilol (1.0 [0.88-1.08] and 1.2 [0.9-1.5]) and the carvedilol plus NAC groups (1.06 [0.9-1.18] and 1.1 [1.0-1.21] mg/dL; all P values >0.05). Postoperative day 3, day 5, and peak creatinine levels were lower in the carvedilol plus NAC group (1.11 [1.0-1.23], 1.14 [1.0-1.25] and 1.15 [1.0-1.25]) as compared with the metoprolol (1.4 [1.3-1.49], 1.3 [1.0-1.54] and 1.3 [1.0-1.54]) or carvedilol groups (1.2 [1.0-1.52], 1.25 [1.0-1.52] and 1.25 [1.0-1.55] mg/dL; all P values <0.05), but were similar between the metoprolol and carvedilol groups (all P values >0.05).

CONCLUSIONS

Combined carvedilol and NAC decreased ARI incidence as compared with carvedilol or metoprolol. No difference was detected between carvedilol and metoprolol.

Economic impact of switching from metoprolol to nebivolol for hypertension treatment: a retrospective database analysis

OBJECTIVE

To estimate the real-world economic impact of switching hypertensive patients from metoprolol, a commonly prescribed, generic, non-vasodilatory β1-blocker, to nebivolol, a branded-protected vasodilatory β1-blocker.

METHODS

Retrospective analysis with a pre-post study design was conducted using the MarketScan database (2007-2011). Hypertensive patients continuously treated with metoprolol for ≥6 months (pre-period) and then switched to nebivolol for ≥6 months (post-period) were identified. The index date for switching was defined as the first nebivolol dispensing date. Data were collected for the two 6-month periods pre- and post-switching. Monthly healthcare resource utilization and healthcare costs pre- and post-switching were calculated and compared using Wilcoxon test and paired t-test. Medical costs at different years were inflated to the 2011 dollar.

RESULTS

In total, 2259 patients (mean age: 60 years; male: 52%; cardiovascular [CV] disease: 37%) met the selection criteria. Switching to nebivolol was associated with statistically significant reductions in the number of all-cause hospitalization (-33%; p < 0.01), CV-related hospitalizations (-60%; p < 0.01), and outpatient visits (-7%; p < 0.01). Monthly inpatient costs were reduced by $111 (p < 0.01), while monthly drug costs increased by $52 (p < 0.01). No statistically significant differences were found in overall costs and costs of outpatient or ER visits. Sensitivity analyses, conducted using various lengths of medication exposure, controlling for spill-over effect or excluding patients with compelling indications for metoprolol, all found some level of reduction in resource utilization and no significant difference in overall healthcare costs.

CONCLUSIONS

This real-world study suggests that switching from metoprolol to nebivolol is associated with an increase in medication costs and significant reductions in hospitalizations and outpatient visits upon switching, resulting in an overall neutral effect on healthcare costs. These results may be interpreted with caution due to lack of a comparator group and confounding control caused by design and limitations inherent in insurance claims data.