Association of Beta-Blockers with Survival on Patients Presenting with ACS Treated with PCI: A Propensity Score Analysis from the BleeMACS Registry

Influence of left ventricular systolic function on the long-term benefit of beta-blockers after ST-segment elevation myocardial infarction

INTRODUCTION

Beta-blockers are recommended after ST-elevation myocardial infarction (STEMI), but their benefit in patients with preserved left ventricular ejection fraction (LVEF) is unclear.

METHODS

Consecutive patients discharged in sinus rhythm after STEMI between January 2010 and April 2015 were followed until December 2017. Percutaneous coronary intervention (PCI) was performed in 969 (99.7%, including 112 with rescue PCI) and three (0.3%) received only thrombolytic therapy without rescue PCI.

RESULTS

Of these 972 patients, mean age 62.6±13.5 years, 212 (21.8%) were women and 835 (85.9%) were prescribed beta-blockers at discharge. Patients who did not receive beta-blockers had more comorbidities than those who did, including chronic obstructive pulmonary disease (14.6% vs. 4.2%), anemia (8.0% vs. 3.7%), and cancer (7.3% vs. 2.8%), and more frequently had inferior STEMI (75.9% vs. 56.0%) and high-grade atrioventricular block (13.1% vs. 5.3%) (all p<0.01). After a mean follow-up of 49.6±24.9 months, beta-blocker treatment at discharge was independently associated with lower mortality (HR 0.61, 95% confidence interval [CI] 0.38-0.96, p=0.03). This effect was present in 192 patients with LVEF ≤40% (HR 0.57, 95% 95% CI 0.34-0.97, p=0.04) but was not clear in 643 patients with LVEF >40% (HR 0.67, 95% 95% CI 0.25-1.76, p=0.42).

CONCLUSION

In the LVEF >40% group, the results raise reasonable doubts about the real benefit of systematic use of beta-blockers as treatment for these patients. These findings reinforce the need for large randomized clinical trials within this group of patients.

Efficacy of Long-Term Oral Beta-Blocker Therapy in Patients Who Underwent Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction With Preserved Left Ventricular Ejection Fraction: A Systematic Review and Meta-analysis

ABSTRACT

After the results of the first multicenter, prospective randomized clinical trial (RCT) evaluating long-term efficacy of oral beta-blockers in patients with preserved left ventricular ejection fraction (LVEF) after ST elevation myocardial infarction (STEMI), we decided to conduct an updated systematic review and meta-analysis to evaluate the long-term efficacy of oral beta-blocker use in patients with preserved LVEF who underwent percutaneous coronary intervention (PCI) for STEMI. A time-limited search from January 1, 1999, to April 16, 2020, on PubMed and EMBASE was conducted on April 16, 2020, for observational studies and clinical trials evaluating the efficacy of long-term oral beta-blockers in patients with preserved LVEF after STEMI treated with PCI. The comparative outcomes between beta-blockers and non-beta-blockers were assessed by pooling weighted odds ratio (OR) with 95% confidence interval (CI) using random-effects model. The outcomes of interest were all-cause mortality and major adverse cardiac event (MACE). Twelve studies (11 observational and 1 RCT) comprising 32,108 patients (19,740 on beta-blocker therapy and 12,368 without beta-blocker therapy) were included. Of which, 75% percent were male (mean age of 64 years: 63.87 ± 3.01 years on beta-blocker therapy and 64.76 ± 3.02 years on non-beta-blocker therapy; P = 0.129) with a follow-up of up to 4.7 years. Unadjusted all-cause mortality [OR = 0.58 (95% CI: 0.42-0.79)] and adjusted all-cause mortality [OR = 0.64 (95% CI: 0.48-0.87)] were significantly lower in patients on the long-term beta-blocker therapy group. However, unadjusted MACE [OR = 0.87 (95% CI: 0.70-1.08)] was not reduced with beta-blocker therapy in these patients. Patients with preserved LVEF after STEMI treated with PCI on long-term oral beta-blocker therapy have a significant reduction in risk of all-cause mortality, without an effect on MACE rates. The only RCT included showed neutral effect, so results of ongoing RCTs are anticipated. Considering that the only high-quality data (RCT) suggest a neutral effect, one should be cautious in interpreting the conclusion.

[Changes in the management of patients with acute coronary syndrome - have the disease outcomes changed?]

Aim        To analyze results of changing the management tactics in patients with acute coronary syndrome (ACS) in clinical practice from 2004 through 2018 expressed as improvement in prognosis.Material and methods        Results of two observational studies were analyzed: ORACLE I (2004-2007), which included 1193 patients with ACS (mean age, 61.1±11.69 years; men, 63.3 %) and ORACLE II (2014-2017), which included 1652 patients from 4 vascular centers (mean age, 64.61±12.67 years; men, 62.3 %).Results   Patients included into the ORACLE II study in 2014 were significantly older and the proportion of patients with diabetes mellitus was greater than in the ORACLE I study (14.7 and 22.6 %, respectively). After matching the groups by major clinical characteristics, it was found that introducing the invasive management tactics for ACS patients was associated with a reduced rate of all-cause death (from 8.2 to 6.1 % for one year), a tendency towards decreased number of coronary death cases (from 5.6 to 4.0 %), and a decrease in risk of recurrent coronary complications (from 17.4  to 7.7 %).Conclusion            Implementing the vascular program statistically significantly decreased the total death rate for at least one-year observation in comparable patient groups.

Role of beta blockers following percutaneous coronary intervention for acute coronary syndrome

AIMS

There is a paucity of evidence supporting routine beta blocker (BB) use in patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). The aim of this study was to evaluate BB use post PCI and its association with mortality. Furthermore, the study aimed to evaluate the association between BB and mortality in the subgroups of patients with left ventricular ejection fraction (LVEF) <35%, LVEF 35%-50% and LVEF >50%.

METHODS

Using a large PCI registry, data from patients with ACS between January 2005 and June 2017 who were alive at 30 days were analysed. Those patients taking BB at 30 days were compared with those who were not taking BB. The primary outcome was all-cause mortality. The mean follow-up was 5.3±3.5 years.

RESULTS

Of the 17 562 patients, 83.3% were on BB. Mortality was lower in the BB group (13.1% vs 19.5%, p=0.0001). Multivariable Cox proportional hazards model showed that BB use was associated with lower overall mortality (adjusted HR 0.87, 95% CI 0.78 to 0.97, p=0.014). In the subgroup analysis, BB use was associated with reduced mortality in LVEF <35% (adjusted HR 0.63, 95% CI 0.44 to 0.91, p=0.013), LVEF 35%-50% (adjusted HR 0.80, 95% CI 0.68 to 0.95, p=0.01), but not LVEF >50% (adjusted HR 1.03, 95% CI 0.87 to 1.21, p=0.74).

CONCLUSION

BB use remains high and is associated with reduced mortality. This reduction in mortality is primarily seen in those with reduced ejection fraction, but not in those with preserved ejection fraction.

Poor adherence to beta-blockers is associated with increased long-term mortality even beyond the first year after an acute coronary syndrome event

Background: Acute coronary syndrome (ACS) patients are widely treated with long-term beta-blocker therapy after cardiac event. Especially for low-risk patients, the benefits of beta-blockers on survival and the optimal therapy duration remain unclear. We investigated the effect of adherence to beta-blockers on long-term survival of ACS patients.Methods and results: A total of 1855 consecutive ACS patients who underwent angiography and survived 30 days after were followed for a median of 8.6 years. During follow-up, 30.1% (n = 558) of patients died. Adherence was assessed as yearly periods covered by medication purchases and investigated as a dynamic time-dependent variable in Cox proportional hazards models. In a univariable model, non-adherence to beta-blockers was associated with higher all-cause mortality (Hazard ratio [HR] 2.99, 95% confidence interval [CI] 2.50-3.57; p < .001). Results were similar in multivariable models on both overall survival (HR 1.84, 95% CI 1.51-2.24; p < .001) and on 1-year landmark survival (HR 1.74, 95% CI 1.41-2.14; p < .001). In subgroup analyses, the increase in all-cause mortality was consistent among low-risk patients (HR 1.60, 95% CI 1.16-2.21; p = .004).Conclusion: Poor adherence to beta-blockers is associated with increased long-term mortality among ACS patients. Even low-risk patients seem to benefit from long-term beta-blocker therapy.Key messagesAdherence to secondary prevention medications diminishes drastically over the years after an ACS event.Non-adherence to β-blockers is associated with increased long-term mortality of ACS patients, and the effect on survival extends beyond the first year after an ACS event.Our follow-up was exceptionally lengthy with median follow-up period of 8.6 years.

Do Patients need Lifelong β-Blockers after an Uncomplicated Myocardial Infarction?

The lifelong use of β-adrenoceptor antagonists (β-blockers) after a myocardial infarction (MI) has been the standard of care based on trials performed before the era of revascularization, when heart failure was common. Large randomized trials in the mid-1980s demonstrated that β-blockers played a major role in improving the in-hospital and long-term survival of patients admitted for MI. However, the implementation of rapid myocardial reperfusion led to a substantial survival benefit and a reduction of heart failure because of reduced infarct size. Modern large longitudinal registries did not provide sufficient evidence to support long-term β-blocker therapy in patients with uncomplicated acute MI. The long-term prescription of this therapy has become a matter of debate given the lack of contemporary evidence, frequent side effects, and treatment adherence issues. Furthermore, this shift into the reperfusion era led to a downgraded recommendation for the use of β-blockers in post-MI patients (class IIa B recommendation) in the 2017 European Society of Cardiology (ESC) recommendations for the treatment of ST-segment elevation MI (STEMI). Three large ongoing multicenter randomized trials (AβYSS, REDUCE-SWEDEHEART, and REBOOT-CNIC) are evaluating early discontinuation of β-blockers after an uncomplicated acute MI. The tested hypothesis is that β-blocker withdrawal is safe versus major adverse cardiovascular events and improves quality of life by reducing side effects. Thus, the present review summarizes the exhaustive evidence-based data for long-term β-blocker use after uncomplicated MI and the ongoing trials.