Beta-blockers for congestive heart failure: what is the current consensus?

Histamine H2 receptor antagonist exhibited comparable all-cause mortality-decreasing effect as β-blockers in critically ill patients with heart failure: a cohort study

Background: Our previous study reported that histamine H2 receptor antagonists (H2RAs) exposure was associated with decreased mortality in critically ill patients with heart failure (HF) through the same pharmacological mechanism as β-blockers. However, population-based clinical study directly comparing the efficacy of H2RAs and β-blockers on mortality of HF patients are still lacking. This study aims to compare the association difference of H2RAs and β-blockers on mortality in critically ill patients with HF using the Medical Information Mart for Intensive Care III database (MIMIC-III). Methods: Study population was divided into 4 groups: β-blockers + H2RAs group, β-blockers group, H2RAs group, and Non-β-blockers + Non-H2RAs group. Kaplan-Meier curves and multivariable Cox regression models were employed to evaluate the differences of all-cause mortalities among the 4 groups. Propensity score matching (PSM) was used to increase comparability of four groups. Results: A total of 5593 patients were included. After PSM, multivariate analyses showed that patients in H2RAs group had close all-cause mortality with patients in β-blockers group. Furthermore, 30-day, 1-year, 5-year and 10-year all-mortality of patients in β-blockers + H2RAs group were significantly lower than those of patients in β-blockers group, respectively (HR: 0.64, 95%CI: 0.50-0.82 for 30-day; HR: 0.80, 95%CI: 0.69-0.93 for 1-year mortality; HR: 0.83, 95%CI: 0.74-0.93 for 5-year mortality; and HR: 0.85, 95%CI: 0.76-0.94 for 10-year mortality, respectively). Conclusion: H2RAs exposure exhibited comparable all-cause mortality-decreasing effect as β-blockers; and, furthermore, H2RAs and β-blockers had additive or synergistic interactions to improve survival in critically ill patients with HF.

Hawthorn (Crataegus spp.) in the treatment of cardiovascular disease

The medicinal properties of hawthorn (Crataegus spp., a genus comprising approximately 300 species) have been utilized by many cultures for a variety of therapeutic purposes for many centuries. In the Western world cardiovascular disease (CVD) has become one of the single most significant causes of premature death. Echoing this situation, more recent research into the therapeutic benefits of hawthorn preparations has focused primarily upon its cardiovascular effects. This review covers research into the various mechanisms of action proposed for Crataegus preparations, clinical trials involving Crataegus preparations, and the herb's safety profile.Clinical trials reviewed have been inconsistent in terms of criteria used (sample size, preparation, dosage, etc) but have been largely consistent with regard to positive outcomes. An investigation into data available to date regarding hawthorn preparations and herb/drug interactions reveals that theoretical adverse interactions have not been experienced in practice. Further, adverse reactions relating to the use of hawthorn preparations are infrequent and mild, even at higher dosage ranges. A recent retrospective study by Zick et al. has suggested a negative outcome for the long-term use of hawthorn in the prognosis of heart failure. These findings are examined in this paper.Although further research is needed in certain areas, current research to date suggests that hawthorn may potentially represent a safe, effective, nontoxic agent in the treatment of CVD and ischemic heart disease (IHD).

Hawthorn extract for treating chronic heart failure

BACKGROUND

Hawthorn extract is advocated as an oral treatment option for chronic heart failure. Also, the German Commission E approved the use of extracts of hawthorn leaf with flower in patients suffering from heart failure graded stage II according to the New York Heart Association.

OBJECTIVES

To assess the benefits and harms as reported in double-blind randomised clinical trials of hawthorn extract compared with placebo for treating patients with chronic heart failure.

SEARCH STRATEGY

We searched CENTRAL on The Cochrane Library (issue 2, 2006), MEDLINE (1951 to June 2006), EMBASE (1974 to June 2006), CINAHL (1982 to June 2006) and AMED (1985 to June 2006). Experts and manufacturers were contacted. Language restrictions were not imposed.

SELECTION CRITERIA

To be included, studies were required to state that they were randomised, double-blind, and placebo controlled, and used hawthorn leaf and flower extract monopreparations.

DATA COLLECTION AND ANALYSIS

Two reviewers independently performed the selection of studies, data extraction, and assessment of methodological quality. Data were entered into RevMan 4.2 software. Results from continuous data were reported as weighted mean difference (WMD) with 95% confidence interval (CI). Where data were suitable for combining, pooled results were calculated.

MAIN RESULTS

Fourteen trials met all inclusion criteria and were included in this review. In most of the studies, hawthorn was used as an adjunct to conventional treatment. Ten trials including 855 patients with chronic heart failure (New York Heart Association classes I to III) provided data that were suitable for meta-analysis. For the physiologic outcome of maximal workload, treatment with hawthorn extract was more beneficial than placebo (WMD (Watt) 5.35, 95% CI 0.71 to 10.00, P < 0.02, n = 380). Exercise tolerance were significantly increased by hawthorn extract (WMD (Watt x min) 122.76, 95% CI 32.74 to 212.78, n = 98). The pressure-heart rate product, an index of cardiac oxygen consumption, also showed a beneficial decrease with hawthorn treatment (WMD (mmHg/min) -19.22, 95% CI -30.46 to -7.98, n = 264). Symptoms such as shortness of breath and fatigue improved significantly with hawthorn treatment as compared with placebo (WMD -5.47, 95% CI -8.68 to -2.26, n = 239). No data on relevant mortality and morbidity such as cardiac events were reported, apart from one trial, which reported deaths (three in active, one in control) without providing further details. Reported adverse events were infrequent, mild, and transient; they included nausea, dizziness, and cardiac and gastrointestinal complaints.

AUTHORS' CONCLUSIONS

These results suggest that there is a significant benefit in symptom control and physiologic outcomes from hawthorn extract as an adjunctive treatment for chronic heart failure.

Hawthorn extract for treating chronic heart failure: meta-analysis of randomized trials

The aim of this meta-analysis was to assess the evidence from rigorous clinical trials of the use of hawthorn extract to treat patients with chronic heart failure. We searched the literature using MEDLINE, EMBASE, the Cochrane Library, CINAHL, CISCOM, and AMED. Experts on and manufacturers of commercial preparations containing hawthorn extract were asked to contribute published and unpublished studies. There were no restrictions about the language of publication. Two reviewers independently performed the screening of studies, selection, validation, data extraction, and the assessment of methodological quality. To be included, studies were required to state that they were randomized, double-blind, and placebo controlled, and used hawthorn extract monopreparations. Thirteen trials met all inclusion criteria. In most of the studies, hawthorn was used as an adjunct to conventional treatment. Eight trials including 632 patients with chronic heart failure (New York Heart Association classes I to III) provided data that were suitable for meta-analysis. For the physiologic outcome of maximal workload, treatment with hawthorn extract was more beneficial than placebo (weighted mean difference, 7 Watt; 95% confidence interval [CI]: 3 to 11 Watt; P < 0.01; n = 310 patients). The pressure-heart rate product also showed a beneficial decrease (weighted mean difference, -20; 95% CI: -32 to -8; n = 264 patients) with hawthorn treatment. Symptoms such as dyspnea and fatigue improved significantly with hawthorn treatment as compared with placebo. Reported adverse events were infrequent, mild, and transient; they included nausea, dizziness, and cardiac and gastrointestinal complaints. In conclusion, these results suggest that there is a significant benefit from hawthorn extract as an adjunctive treatment for chronic heart failure.

Extended-release metoprolol succinate in chronic heart failure

OBJECTIVE

To review the pharmacology, pharmacokinetics, efficacy, and tolerability of extended-release (ER) metoprolol succinate and its role in the management of chronic heart failure.

DATA SOURCES

A MEDLINE search of English-language literature (1990-October 2002) was conducted using congestive heart failure and metoprolol CR/XL or metoprolol CR/ZOK as search terms to identify pertinent studies.

STUDY SELECTION/DATA EXTRACTION

All of the articles identified from the data sources were evaluated, with priority given to randomized, double-blind, placebo-controlled studies.

DATA SYNTHESIS

ER metoprolol succinate is a controlled-release tablet designed to produce even and consistent beta(1)-blockade throughout the 24-hour dosing interval, with less fluctuation in metoprolol plasma concentrations compared with immediate-release metoprolol. Three randomized, double-blind, placebo-controlled trials have evaluated the efficacy of ER metoprolol succinate in the treatment of patients with chronic heart failure. The MERIT-HF (Metoprolol CR/XL Randomized Intervention Trial in Congestive Heart Failure) study, the largest of these trials and the largest randomized mortality trial with beta-blockers in heart failure to date, demonstrated that ER metoprolol succinate reduced the relative risk of all-cause mortality by 34% versus placebo. Furthermore, the relative risk of the combined endpoint of mortality plus all-cause hospitalizations was reduced by 19% and sudden death was reduced by 41%. The benefits of therapy were evident in various patient subgroups, including elderly patients and those with diabetes mellitus. ER metoprolol succinate was generally well tolerated, with a similar proportion of patients discontinuing therapy due to adverse events relative to placebo (9.8% and 11.7%, respectively).

CONCLUSIONS

ER metoprolol succinate therapy provides substantial mortality and morbidity benefits in patients with New York Heart Association class II and III heart failure who are stabilized on angiotensin-converting enzyme inhibitors and diuretics. ER metoprolol succinate is administered once daily, is well tolerated, and provides consistent beta(1)-blockade over the 24-hour dosing interval.

Titration of beta-blockers in heart failure. How to maximize benefit while minimizing adverse events

Data from large clinical trials indicate that beta-blocker therapy can be successfully initiated and adjusted upward in most patients with stable chronic heart failure who already take standard heart failure therapy. Such therapy typically includes ACE inhibitors, diuretics, and digoxin. With optimal titration and maintenance strategies, beta-blockers are effective and well tolerated in these patients. It is recommened that all patients with clinically stable mild to moderate chronic heart failure (NYHA class II or III), no contraindications to beta-blocker use, and an LVEF less than 40% should be treated with beta-blockers. Based on the results of recent clinical trials on heart failure, beta-blocker therapy should be initiated at a low dose and slowly tirtrated upward as tolerated. A patient's heart failure should be stable for at least 2 weeks before the dose is adjusted upward. Slow titration facilitates maximal tolerability. In primary care practice, physicians should apply titration strategies and target dosed that have been demonstrated to reduce morbidity and mortality in clinical trials. Although worsening heart failure or other adverse events occur in a minority of patients who take beta-blockers, these effects can be managed by adjusting the dose of ACE inhibitor or diuretic, or both, or by temporarily withholding the beta-clocker. Currently, professional treatment guidelines recommend beta-blocker therapy in combination with ACE inhibitors an diuretics as the standard of care in the treatment of heart failure.

Potential adverse drug events in an indigent and homeless geriatric population

OBJECTIVE

To identify potential adverse drug events (ADEs) in a geriatric ambulatory population using the modified Beers criteria.

METHODS

This is a cross-sectional study of an indigent and homeless geriatric population served by a network of six primary healthcare clinics with clinical pharmacy services. Medical records of patients > or = 65 years old visiting the clinics between December 1999 and April 2000 were retrospectively reviewed by a clinical pharmacist. Medications meeting the modfied Beers criteria were evaluated for the most common drug classes involved, severity potential, and dose or disease state restrictions. Following the identification of medications meeting Beers criteria, the pharmacist left a written recommendation regarding use of alternative drugs or doses in the medical record. Physician acceptance of pharmacy recommendations was also evaluated.

RESULTS

Medical records of 146 patients (71.9% women, average age 72.6 +/- 6.7 y) were reviewed. Overall, 52 patients (35.6%) had 70 medications with the potential for causing an ADE based on the modified Beers criteria The most commonly identified medication classes were narcotic analgesics (20.0%), antihypertensives (20.0%), and antihistamines (14.3%). Fifteen of these medications (21.4%) had a high severity potential. Identified medications met the following modified Beers criteria: 41.4% were inappropriate in a specific disease state, 38.6% were inappropriate for the elderly, 10.0% exceeded maximum dosage guidelines, and 10.0% were inappropriate for both the elerly and the patients disease state. Approximately 60% of pharmacy recommendations were accepted by physicians.

CONCLUSIONS

The modified Beers criteria are a useful tool for reviewing medical records to identify potential ADEs in an ambulatory geriatric population.

Results from post-hoc analyses of the CIBIS II trial: effect of bisoprolol in high-risk patient groups with chronic heart failure

BACKGROUND

The beneficial effects of the beta-blocker bisoprolol on mortality and rate of hospitalisation as well as its safety in patients with chronic heart failure has been proven. However, its efficacy in patients in whom beta-blockers have traditionally been contraindicated or caution has been advised has not been clearly determined. Therefore, analyses in high-risk subgroups of patients taking part in CIBIS II have been performed to investigate the effect of bisoprolol in elderly patients, in patients with type 2 diabetes, with renal failure, NYHA functional class IV or concomitantly treated with digitalis, aldosterone antagonists or amiodarone.

METHODS

High-risk subgroups of patients with chronic heart failure taking part in the CIBIS II study were retrospectively analysed with respect to mortality, hospitalisation, combined endpoint of cardiovascular mortality or hospitalisation for cardiovascular reasons and treatment withdrawal as well as cause of death and hospitalisation. Analysis is based on intention-to-treat.

RESULTS

It was demonstrated that in spite of the expected increase in the overall risk of death and hospitalisation, patients who are diabetic, have renal impairment, NYHA class IV symptoms, are elderly, are taking either digitalis, amiodarone or aldosterone antagonists as co-medication benefit equally from beta-blockade with bisoprolol as patients without these complications or drugs. Benefit was shown for the primary endpoint all cause mortality, as well as for the secondary endpoints.

CONCLUSIONS

Contrary to the hitherto prevailing doctrine of not using beta-blockers in high risk patient groups with chronic heart failure, retrospective analyses of the CIBIS II study justify the use of this drug class in patients regardless of age, NYHA functional class, the presence of diabetes, renal impairment or concomitant treatment with digitalis, amiodarone or aldosterone antagonists.