Long-term survival effect of metoprolol in dilated cardiomyopathy. The SPIC (Italian Multicentre Cardiomyopathy Study) Group

Contemporary Outcome in Patients With Idiopathic Dilated Cardiomyopathy

Outcome is better in patients with idiopathic dilated cardiomyopathy (IDC) than in ischemic heart failure (HF), but morbidity and mortality are nevertheless presumed to be substantial. Most data on the prognosis in IDC stem from research performed before the widespread use of current evidence-based treatment, including implantable devices. We report outcome data from a cohort of patients with IDC treated according to current HF guidelines and compare our results with previous figures: 102 consecutive patients referred to our tertiary care hospital with idiopathic IDC and a left ventricular ejection fraction <40% were included in a prospective cohort study. After extensive baseline work-up, follow-up was performed after 6 and 13 months. Vital status and heart transplantation were recorded. Over the first year of follow-up, the patients were on optimal pharmacological treatment, and 24 patients received implantable devices. Left ventricular ejection fraction increased from 26 ± 10% to 41 ± 11%, peak oxygen consumption increased from 19.5 ± 7.1 to 23.4 ± 7.8 ml/kg/min, and functional class improved substantially (all p values <0.001). After a median follow-up of 3.6 years, 4 patients were dead, and heart transplantation had been performed in 9 patients. According to our literature search, survival in patients with IDC has improved substantially over the last decades. In conclusion, patients with IDC have a better outcome than previously reported when treated according to current guidelines.

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.

Heart failure and sudden death in dilated cardiomyopathy: a hidden competition we should not forget about when modelling mortality

RATIONALE, AIMS AND OBJECTIVES

This paper discusses the use of bivariate survival curve estimators jointly with a competing risk Cox model to analyse mortality in dilated cardiomyopathy due to heart failure (HF) or sudden death (SD), without assuming independence between outcomes. The goal of the manuscript is to suggest a possible protocol for the analysis of competing risk events, mimicking the common approaches used in the univariate case.

METHODS

The non-parametric bivariate survival estimators are used to estimate a multivariate proportional hazard model for dealing with SD or HF in a long-term prospective cohort of 235 patients, recruited from 1978 to 1992. Patients have been stratified, among others, by age, severity and treatment. The latter has been considered under two specific protocols of analysis: intention to treat and actual treatment.

RESULTS

The bivariate survival curves show different survival probabilities for HF and SD. For HF the force of mortality acts early and then slows down as follow-up increases, while for SD the mortality is lower initially and increases later in time. Under competing risk analysis, evidence of treatment effect is shown only in the actual treatment protocol, in contrast with the results provided by standard Cox regression.

CONCLUSIONS

One of the advantages of non-parametric bivariate survival estimation in the presence of competing risks is that parameters may be interpreted in much the same way as those estimated by the standard Cox regression. Moreover, ignoring the competing risk structure may provide a misleading interpretation of the results.

National trends in outcomes among elderly patients with heart failure

PURPOSE

Despite dramatic changes in heart failure management during the 1990s, little is known about the national heart failure mortality trends during this time period, particularly among the elderly. The purpose of this study was to determine temporal trends in outcomes of elderly patients with heart failure between 1992 and 1999.

SUBJECTS AND METHODS

We analyzed a national sample of 3,957,520 Medicare beneficiaries aged 65 years or more who were hospitalized with heart failure between 1992 and 1999, assessing temporal trends in 30-day and 1-year all-cause mortality and 30-day and 6-month all-cause hospital readmission. In risk-adjusted analyses, mortality and readmission for each year between 1994 and 1999 were compared with the referent year of 1993.

RESULTS

Crude 30-day and 1-year mortality decreased slightly (range for 1992-1999: 11.0%-10.3% and 32.5%-31.7%, respectively), whereas 30-day and 6-month readmission increased (10.2%-13.8% and 35.4%-40.3%, respectively). After risk adjustment, there was no change in 30-day mortality between 1993 and 1999 (eg, for 1999 vs 1993, odds ratio [OR] 1.01, 95% confidence interval [CI], 1.00-1.02). One-year mortality was lower in 1994 compared with 1993 (OR 0.91, 95% CI, 0.90-0.92), but data from subsequent years suggested no continuous improvement after 1994 (1999 vs 1993: OR 0.93, 95% CI, 0.92-0.94). Thirty-day readmission increased (1999 vs 1993: OR 1.09, 95% CI, 1.07-1.10), but there was no change in 6-month readmission (1999 vs 1993: OR 1.00, 95% CI, 0.99-1.01).

CONCLUSION

We found no substantial improvement in mortality and hospital readmission during the 1990s among elderly patients hospitalized with heart failure. These findings suggest that recent innovations in heart failure management have not yet translated into better outcomes in this population.

Rapid titration of carvedilol in patients with congestive heart failure: a randomized trial of automated telemedicine versus frequent outpatient clinic visits

BACKGROUND

Because of potential side effects and logistical difficulty of titrating medications, outpatients with congestive heart failure rarely receive appropriate doses of carvedilol or other beta-blockers. To address these obstacles, we studied if an automated telemedicine system named TeleWatch (TW) could facilitate carvedilol titration in outpatients with left ventricular systolic dysfunction.

METHODS

Forty-nine patients with New York Heart Association class II and III left ventricular systolic dysfunction, who were tolerating appropriate afterload-reducing therapy and not receiving beta-blockers, were enrolled into a 3-month study. Patients were randomized to have clinic-only (CO) (n = 24) carvedilol titration or titrations which combined clinic visits with TW monitoring (n = 25). All patients were seen in clinic biweekly, and those in the TW group were remotely monitored daily. Using a predefined algorithm, patients in the CO and TW groups were eligible for carvedilol titration on a biweekly or weekly basis, respectively, by physicians blinded to group assignment.

RESULTS

There was no statistical difference in the mean final daily dose of carvedilol between the CO and TW groups (39.4 vs 36.2 mg/d, P = .52). Because remote telemedicine titrations were as successful as titrations in the clinic, the time to reach the final dose of carvedilol was significantly shorter in the TW group (33.6 vs 63.7 days, P < .0001). There were 5 serious adverse events in the study, 4 of which were in the TW group (P = .29); however, TW prospectively detected 2 adverse events.

CONCLUSIONS

Remote monitoring with an automated telemedicine system can successfully facilitate titration of carvedilol in outpatients with New York Heart Association class II and III congestive heart failure.

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

The use of beta-blockers in addition to digoxin, diuretics, and ACE inhibitors was shown to be beneficial for patients with chronic heart failure. Benefits include decreased hospitalizations, decreased need for heart transplant, and decreased mortality. The fact that beta-blockers may improve a sense of well-being, as well as quality of life, for patients with chronic heart failure, is perhaps the greatest advantage to including these drugs in HF therapy.

Timing of cardiac transplantation in patients with heart failure receiving β-adrenergic blockers

BACKGROUND

Previous work shows that patients with heart failure patients who have peak oxygen consumption (VO2 peak) >14 ml/kg/min do not derive a survival benefit from cardiac transplantation. However, this was shown before beta-blocker therapy for patients with systolic heart failure became common, and beta-blockers improve survival in patients with heart failure without changing VO(2) peak. Our purpose was to re-evaluate the utility of VO(2) peak >14 ml/kg/min as an indicator of the need for cardiac transplantation in patients with heart failure who are taking beta-blockers.

METHODS

Actuarial, hemodynamic, and exercise ventilatory data were collected from 540 patients with heart failure, 256 of whom were taking beta-blockers. We tracked death and cardiac transplantation. We stratified the percentage of patients event-free 1 and 3 years after VO(2) peak study by their VO(2) peak and beta-blocker status, and compared 1- and 3-year post-transplant survival (United Network of Organ Sharing [UNOS] data). We also compared total mortality for the patients with heart failure as stratified by beta-blocker stats and VO(2) peak (excluding the 42 who underwent transplantation) with UNOS post-transplant survival.

RESULTS

Patients with heart failure who were receiving beta-blockers and whose VO(2) peak was > or =12 ml/kg/min had greater 1- and 3-year event-free survival rates (95% confidence intervals, 92.6%-96.6% and 85.8%-96.0%) than did post-transplant patients (83.9%-86.3% and 75.4%-76.6%). However, in patients with heart failure not taking beta-blockers, VO(2) peak <14 ml/kg/min was associated with worse 3-year survival (38.9 - 62.1%) than that for post-transplant patients. Excluding the 42 patients with heart failure in our study who underwent transplantation and then evaluating survival of the remaining patients with heart failure (not event-free survival) did not substantially change these results.

CONCLUSIONS

Patients with heart failure who are receiving beta-blockers do not derive a survival advantage at 1 and 3 years after cardiac transplantation if VO(2) peak is > or =12 ml/kg/min. Patients not taking beta-blockers whose VO(2) peak is <14 ml/kg/min have superior survival with cardiac transplantation.

The effect of beta-adrenergic blockers on the prognostic value of peak exercise oxygen uptake in patients with heart failure

OBJECTIVES

Our aim was to determine the effect of beta-adrenergic blockade on the prognostic value of peak oxygen consumption testing in patients with heart failure.

BACKGROUND

Peak oxygen consumption has been shown to be a useful prognostic tool in patients with heart failure. However, studies demonstrating the utility of peak oxygen consumption were conducted before beta-blocker therapy became widespread. Thus, our objective was to determine the effect of beta-blockers on the prognostic value of peak oxygen consumption in patients with heart failure.

METHODS

Actuarial, anthropomorphic, hemodynamic and exercise ventilatory data were collected from 369 patients with heart failure. Death and orthotopic heart transplants were the events tracked. Patients were divided into those taking beta-blockers and those not taking them. Event-free survival days were calculated.

RESULTS

One hundred ninety-nine patients on beta-blockers and 170 not on beta-blockers were studied. There were 40 orthotopic heart transplants and 82 deaths during follow-up. Peak oxygen consumption (milliliters per kilogram per minute) trended toward being an independent predictor of event-free survival (p = 0.055). In patients on and not on beta-blockers, a peak oxygen consumption of >14 ml/kg.min was associated with a 1-year event rate of approximately half of that associated with a peak oxygen consumption </=14 ml/kg x min. However, for every level of peak oxygen consumption, the event rate was lower in the group taking beta-blockers.

CONCLUSIONS

Beta-blocker status does not change the predictive power of peak oxygen consumption in patients with heart failure, but beta-blocker status is important to consider when using peak oxygen consumption to predict event-free survival in patients with heart failure.

Role of beta blockers in congestive heart failure

Prolonged activation of the adrenergic nervous system has adverse consequences on the cardiovascular system in patients with congestive heart failure. Beta adrenergic receptor-blocker therapy modifies these deleterious effects. Beta blockers have been shown to improve myocardial function and survival when used in conjunction with conventional treatment with diuretics, angiotensin-converting enzyme inhibitors, and digoxin. Beta blocker therapy in mild-to-moderate heart failure should not be delayed because it causes some reversal of both neurohormonal compensatory mechanisms and the deleterious myocardial remodeling process. This paper reviews the beneficial effects of beta adrenergic receptor-blocker therapy on the pathophysiology, symptoms, left ventricular function, morbidity, and mortality in patients with congestive heart failure. (c)2000 by CHF, Inc.