Beta Blockers in Dilated Cardiomyopathies

Bisoprolol for the treatment of chronic heart failure: A meta-analysis on individual data of two placebo-controlled studies.CIBIS and CIBIS II
Alain Leizorovicz, MD,a Philippe Lechat, MD, PhD,b Michel Cucherat, MD,a and Francoise Bugnard, MSca Lyon and Paris, France
Am Heart J 2002;143:301-7.
Background Despite the available evidence from randomized clinical trials, beta-blockers are often not used optimally in patients with congestive heart failure (CHF). This meta-analysis aims at providing a precise and quantitative estimate of the benefit and risks of long-term bisoprolol on major clinical events in patients with CHF, both overall and in selected subgroups. This may help clinicians in their decisions as to whether to prescribe bisoprolol for their individual patients.
Methods Meta-analysis was performed of results from the 2 randomized, controlled clinical studies in which bisoprolol was compared with placebo (Cardiac Insufficiency Bisoprolol Study [CIBIS and CIBIS II]), which included 3288 patients with proven CHF. The main outcomes were total death, cardiovascular death, sudden death, hospitalization for heart failure, and myocardial infarction.
Results A highly significant 29.3% relative reduction of death (17%, 40%; P = .00003) was observed, as well as significant risk reduction in cardiovascular death and sudden death in favor of bisoprolol. Also, a highly significant relative reduction of 18.4% (25%, 11%; P = .00001) in hospital admission or death was observed. A similar relative reduction of death was consistently observed in selected subgroups of patients.
Conclusions Bisoprolol prevents major cardiovascular events in patients with CHF with a high benefit-to-risk ratio and can be recommended for these patients.

Long term survival effect of metoprolol in dilated cardiomyopathy
A Di Lenarda, R De Maria, A Gavazzi, D Gregori,M Parolini, G Sinagra, L Salvatore, F Longaro, E Bernobich, F Camerini, on behalf of the SPIC (Italian Multicentre Cardiomyopathy Study) Group
Heart 1998;79:337–344

Objective—To evaluate the additive effect of metoprolol treatment on long term incidence of fatal and non-fatal cardiac events in idiopathic dilated cardiomyopathy.
Design—586 patients with idiopathic dilated cardiomyopathy were prospectively enrolled in a multicentre registry and followed up for a mean (SD) of 52 (32) months. Metoprolol, carefully titrated to the maximum tolerated dose, was added to conventional heart failure treatment in 175 patients.
Results—Survival and transplant-free survival at seven years were significantly higher in the 175 metoprolol treated patients than in the remaining 411 on standard treatment (81% v 60%, p < 0.001, and 69% v 49%, p < 0.001, respectively). Bymultivariate analysis, metoprolol independently predicted survival and transplant-free survival (relative risk reduction values for all cause mortality and combined mortality or transplantation 51% (95% confidence interval 21% to 69%), p = 0.002, and 34% (5% to 53%), p = 0.01, respectively). New York Heart Association class, left ventricular end diastolic diameter, and pulmonary wedge pressure were also predictive. Seven year survival (80% v 62%, p = 0.004) and transplant-free survival (68% v 51%, p = 0.005) were significantly higher in 127 metoprolol treated cases than in 127 controls selected from the entire control cohort and appropriately matched. Metoprolol was associated with a 30% reduction in all cause mortality (7% to 48%, p = 0.015) and a 26% reduction in mortality or transplantation (7% to 41%, p = 0.009).
Conclusions—The addition of metoprolol to standard heart failure treatment, including angiotensin converting enzyme inhibitors, was eVective in the long term, reducing both all cause mortality and transplantation in patients with idiopathic dilated cardiomyopathy.

Prakash A, Markham A
Institution: Adis International Limited, Mairangi Bay, Auckland, New Zealand. demail@adis.co.nz
Metoprolol: a review of its use in chronic heart failure.
Drugs. 60(3):647-78, 2000 Sep.

Metoprolol, a relatively selective beta1-blocker, is devoid of intrinsic sympathomimetic activity and possesses weak membrane stabilising activity. The drug has an established role in the management of essential hypertension and angina pectoris, and more recently, in patients with chronic heart failure. The effects of metoprolol controlled-release/extended-release (CR/XL) in patients with stable, predominantly mild to moderate (NYHA functional class II to III) chronic heart failure have been evaluated in the large Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure (MERIT-HF) trial and the much smaller Randomized Evaluation of Strategies for Left Ventricular Dysfunction (RESOLVD) pilot study. Treatment with metoprolol CR/XL was initiated at a low dosage of 12.5 to 25 mg once daily and gradually increased at 2-weekly intervals until the target dosage (200 mg once daily) or maximal tolerated dosage had been attained in patients receiving standard therapy for heart failure. At 12 months, metoprolol CR/XL was associated with a 34% reduction in relative risk of all-cause mortality in patients with chronic heart failure due to ischaemic or dilated cardiomyopathy in the MERIT-HF trial. The incidence of sudden death and death due to progressive heart failure were both significantly decreased with metoprolol CR/XL. Similarly, a trend towards decreased mortality in the metoprolol CR/XL group compared with placebo was observed in the RESOLVD trial. Data from small numbers of patients with severe (NYHA functional class IV) heart failure indicate that metoprolol CR/XL is effective in this subset of patients. However, no firm conclusions can yet be drawn. Improvement from baseline values in NYHA functional class, exercise capacity and some measures of quality of life with metoprolol CR/XL or immediate-release metoprolol were significantly greater than those with placebo. The drug is well tolerated when treatment is initiated in low dosages and gradually increased at intervals of 1 to 2 weeks. Conclusions: Metoprolol CR/XL effectively decreases mortality and improves clinical status in patients with stable mild to moderate (NYHA functional class II or III) chronic heart failure due to left ventricular systolic dysfunction, and the drug is effective in patients with ischaemic or dilated cardiomyopathy. Although limited data indicate that metoprolol CR/XL is effective in patients with severe (NYHA functional class IV) chronic heart failure, more data are needed to confirm these findings. Treatment with metoprolol CR/XL significantly reduced the incidence of sudden death and death due to progressive heart failure.

Domanski MJ, Krause-Steinrauf H, Massie BM, Deedwania P, Follmann D, Kovar D, Murray D, Oren R, Rosenberg Y, Young J, Zile M, Eichhorn E
Institution: Clinical Trials Group, National Heart, Lung, and Blood Institute/NIH, 6701 Rockledge Drive, Room 8146, Bethesda, MD 20892-7936, USA
A comparative analysis of the results from 4 trials of beta-blocker therapy for heart failure: BEST, CIBIS-II, MERIT-HF, and COPERNICUS.
Journal of Cardiac Failure. 9(5):354-63, 2003 Oct.

Recent large randomized, controlled trials (BEST [Beta-blocker Evaluation of Survival Trial], CIBIS-II [Cardiac Insufficiency Bisoprolol Trial II], COPERNICUS [Carvedilol Prospective Randomized Cumulative Survival Study], and MERIT-HF [Metoprolol Randomized Intervention Trial in Congestive Heart Failure]) have addressed the usefulness of beta-blockade in the treatment of advanced heart failure. CIBIS-II, COPERNICUS, and MERIT-HF have shown that beta-blocker treatment with bisoprolol, carvedilol, and metoprolol XL, respectively, reduce mortality in advanced heart failure patients, whereas BEST found a statistically nonsignificant trend toward reduced mortality with bucindolol. We conducted a post hoc analysis to determine whether the response to beta-blockade in BEST could be related to differences in the clinical and demographic characteristics of the study populations. We generated a sample from BEST to resemble the patient cohorts studied in CIBIS-II and MERIT-HF to find out whether the response to beta-blocker therapy was similar to that reported in the other trials. These findings are further compared with COPERNICUS, which entered patients with more severe heart failure. METHODS: To achieve conformity with the entry criteria for CIBIS-II and MERIT-HF, the BEST study population was adjusted to exclude patients with systolic blood pressure <100 mm Hg, heart rate <60 bpm, and age >80 years (exclusion criteria employed in those trials). The BEST comparison subgroup (BCG) was further modified to more closely reflect the racial demographics reported for patients enrolled in CIBIS-II and MERIT-HF. The association of beta-blocker therapy with overall survival and survival free of cardiac death, sudden cardiac death, and progressive pump failure in the BCG was assessed. RESULTS: In the BCG subgroup, bucindolol treatment was associated with significantly lower risk of death from all causes (hazard ratio (HR)=0.77 [95% CI=0.65, 0.92]), cardiovascular death (HR=0.71 [0.58, 0.86]), sudden death (HR=0.77 [0.59, 0.999]), and pump failure death (HR=0.64 [0.45, 0.91]). CONCLUSIONS: Although not excluding the possibility of differences resulting from chance alone or to different properties among beta-blockers, this study suggests the possibility that different heart failure population subgroups may have different responses to beta-blocker therapy.

Simon T, Mary-Krause M, Funck-Brentano C, Lechat P, Jaillon P
Institution: Department of Pharmacology, Saint Antoine University Hospital AP-HP, 27, Rue Chaligny, 75012, Paris, France. tabassome.simon@chusa.jussieu.fr
Bisoprolol dose-response relationship in patients with congestive heart failure: a subgroup analysis in the cardiac insufficiency bisoprolol study(CIBIS< II).
European Heart Journal. 24(6):552-9, 2003 Mar.

AIMS: Whether all patients with congestive heart failure (CHF) need to reach the target dose of beta-blocker to obtain a benefit in terms of survival remains uncertain. METHODS AND RESULTS: We classified by tertile the 2647 patients enrolled in CIBIS II according to the last tolerated dose: low dose (LD: 1.25, 2.5 or 3.75mg/day, n=434), moderate dose (MD: 5 or 7.5mg/day, n=328) and high dose (HD: 10mg/day, n=565) of bisoprolol or placebo (LD=234, MD=278 and HD=808). In both groups, patients tolerating only low doses were significantly older with more severe New York Heart Association (NYHA) functional class and higher frequency of co-morbidities. Treatment withdrawal was associated with a significant increase of mortality in the bisoprolol group (relative hazard (RH)=2.13, 95% confidence interval (CI)=1.43-3.17, p=0.0002). After adjustment, all-cause mortality was significantly reduced in the bisoprolol group compared to placebo regardless of the dose level considered: LD (RH=0.66, 95% CI=0.48-0.92), MD (RH=0.33, 95% CI=0.21-0.51) or HD (RH=0.59, 95% CI=0.40-0.89). CONCLUSIONS: Bisoprolol reduces mortality in CHF patients at all tolerated dose levels and its withdrawal increases the risk of mortality. Efforts should be made to maintain bisoprolol therapy based on the individual patient's tolerability.

Hjalmarson A
Institution: Division of Cardiology, Sahlgren's Hospital, Goteborg, Sweden.
Beneficial effects of metoprolol in idiopathic dilated cardiomyopathy. Metoprolol in Dilated Cardiomyopathy (MDC) Trial Study Group.
Source: Lancet. 342(8885):1441-6, 1993 Dec 11.

Several small studies have suggested beneficial effects of long-term beta-blocker treatment in idiopathic dilated cardiomyopathy. Our large multicentre study aimed to find out whether metoprolol improves overall survival and morbidity in this disorder. 383 subjects with heart failure from idiopathic dilated cardiomyopathy (ejection fraction < 0.40) were randomly assigned placebo or metoprolol. 94% were in New York Heart Association functional classes II and III, and 80% were receiving background treatment. A test dose of metoprolol (5 mg twice daily) was given for 2-7 days; those tolerating this dose (96%) entered randomisation. Study medication was increased slowly from 10 mg to 100-150 mg daily. There were 34% (95% CI -6 to 62%, p = 0.058) fewer primary endpoints in the metoprolol than the placebo group; 2 and 19 patients, respectively, deteriorated to the point of needing transplantation and 23 and 19 died. The change in ejection fraction from baseline to 12 months was significantly greater with metoprolol than with placebo (0.13 vs 0.06, p < 0.0001). Pulmonary capillary wedge pressure decreased more from baseline to 12 months with metoprolol than with placebo (5 vs 2 mm Hg, p = 0.06). Exercise time at 12 months was significantly greater (p = 0.046) in metoprolol-treated than in placebo-treated patients. In patients with idiopathic dilated cardiomyopathy, treatment with metoprolol prevented clinical deterioration, improved symptoms and cardiac function, and was well tolerated.