Clinical outcomes with β-blockers for myocardial infarction: a meta-analysis of randomized trials

Beta-Blockers and Cardiovascular Outcomes in Acute Heart Failure with a History of Coronary Artery Disease and an Ejection Fraction ≥ 40

The prognostic impact of beta-blockers (BB) in coronary artery disease (CAD) is controversial, especially in the post-reperfusion era. We studied in-hospital cardiovascular events in patients hospitalized for acute HF, a previous history of CAD and a left ventricular ejection fraction (LVEF) ≥40%, in relation to BB on admission; and 1-year outcome in relation to BB on discharge, in the GULF aCute heArt failuRe (GULF-CARE) registry. From a total of 5005 patients included in the GULF-CARE registry, 303 patients with a previous history of CAD and a LVEF ≥40% on BB were propensity-matched to 303 patients without BB on admission. In-hospital mortality (OR= 0.82; 95% CI [0.35-1.94]), stroke and cardiogenic shock were not reduced by BB. On discharge, 306 patients on BB, including the ones newly diagnosed with myocardial infarction as a precipitating cause of HF, were propensity-scored matched with 306 patients without BB. Mortality (OR= 0.86; 95%CI [0.51-1.45], hospitalization for HF or PCI/CABG at 1 year were also not reduced by BB at discharge. In summary, our data show that BB have a neutral effect on in-hospital and 1-year outcomes in acute heart failure patients with a previous history of CAD and a LVEF ≥40%.

Beta-blockers for suspected or diagnosed acute myocardial infarction

BACKGROUND

Cardiovascular disease is the number one cause of death globally. According to the World Health Organization, 7.4 million people died from ischaemic heart diseases in 2012, constituting 15% of all deaths. Acute myocardial infarction is caused by blockage of the blood supplied to the heart muscle. Beta-blockers are often used in patients with acute myocardial infarction. Previous meta-analyses on the topic have shown conflicting results ranging from harms, neutral effects, to benefits. No previous systematic review using Cochrane methodology has assessed the effects of beta-blockers for acute myocardial infarction.

OBJECTIVES

To assess the benefits and harms of beta-blockers compared with placebo or no intervention in people with suspected or diagnosed acute myocardial infarction.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS, Science Citation Index Expanded and BIOSIS Citation Index in June 2019. We also searched the WHO International Clinical Trials Registry Platform, ClinicalTrials.gov, Turning Research into Practice, Google Scholar, SciSearch, and the reference lists of included trials and previous reviews in August 2019.

SELECTION CRITERIA

We included all randomised clinical trials assessing the effects of beta-blockers versus placebo or no intervention in people with suspected or diagnosed acute myocardial infarction. Trials were included irrespective of trial design, setting, blinding, publication status, publication year, language, and reporting of our outcomes.

DATA COLLECTION AND ANALYSIS

We followed the Cochrane methodological recommendations. Four review authors independently extracted data. Our primary outcomes were all-cause mortality, serious adverse events according to the International Conference on Harmonization - Good Clinical Practice (ICH-GCP), and major adverse cardiovascular events (composite of cardiovascular mortality and non-fatal myocardial infarction during follow-up). Our secondary outcomes were quality of life, angina, cardiovascular mortality, and myocardial infarction during follow-up. Our primary time point of interest was less than three months after randomisation. We also assessed the outcomes at maximum follow-up beyond three months. Due to risk of multiplicity, we calculated a 97.5% confidence interval (CI) for the primary outcomes and a 98% CI for the secondary outcomes. We assessed the risks of systematic errors through seven bias domains in accordance to the instructions given in the Cochrane Handbook. The quality of the body of evidence was assessed by GRADE.

MAIN RESULTS

We included 63 trials randomising a total of 85,550 participants (mean age 57.4 years). Only one trial was at low risk of bias. The remaining trials were at high risk of bias. The quality of the evidence according to GRADE ranged from very low to high. Fifty-six trials commenced beta-blockers during the acute phase of acute myocardial infarction and seven trials during the subacute phase. At our primary time point 'less than three months follow-up', meta-analysis showed that beta-blockers versus placebo or no intervention probably reduce the risk of a reinfarction during follow-up (risk ratio (RR) 0.82, 98% confidence interval (CI) 0.73 to 0.91; 67,562 participants; 18 trials; moderate-quality evidence) with an absolute risk reduction of 0.5% and a number needed to treat for an additional beneficial outcome (NNTB) of 196 participants. However, we found little or no effect of beta-blockers when assessing all-cause mortality (RR 0.94, 97.5% CI 0.90 to 1.00; 80,452 participants; 46 trials/47 comparisons; high-quality evidence) with an absolute risk reduction of 0.4% and cardiovascular mortality (RR 0.99, 95% CI 0.91 to 1.08; 45,852 participants; 1 trial; moderate-quality evidence) with an absolute risk reduction of 0.4%. Regarding angina, it is uncertain whether beta-blockers have a beneficial or harmful effect (RR 0.70, 98% CI 0.25 to 1.84; 98 participants; 3 trials; very low-quality evidence) with an absolute risk reduction of 7.1%. None of the trials specifically assessed nor reported serious adverse events according to ICH-GCP. Only two trials specifically assessed major adverse cardiovascular events, however, no major adverse cardiovascular events occurred in either trial. At maximum follow-up beyond three months, meta-analyses showed that beta-blockers versus placebo or no intervention probably reduce the risk of all-cause mortality (RR 0.93, 97.5% CI 0.86 to 0.99; 25,210 participants; 21 trials/22 comparisons; moderate-quality evidence) with an absolute risk reduction of 1.1% and a NNTB of 91 participants, and cardiovascular mortality (RR 0.90, 98% CI 0.83 to 0.98; 22,457 participants; 14 trials/15 comparisons; moderate-quality evidence) with an absolute risk reduction of 1.2% and a NNTB of 83 participants. However, it is uncertain whether beta-blockers have a beneficial or harmful effect when assessing major adverse cardiovascular events (RR 0.81, 97.5% CI 0.40 to 1.66; 475 participants; 4 trials; very low-quality evidence) with an absolute risk reduction of 1.7%; reinfarction (RR 0.89, 98% CI 0.75 to 1.08; 6825 participants; 14 trials; low-quality evidence) with an absolute risk reduction of 0.9%; and angina (RR 0.64, 98% CI 0.18 to 2.0; 844 participants; 2 trials; very low-quality evidence). None of the trials specifically assessed nor reported serious adverse events according to ICH-GCP. None of the trials assessed quality of life. We identified two ongoing randomised clinical trials investigating the effect of early administration of beta-blockers after percutaneous coronary intervention or thrombolysis to patients with an acute myocardial infarction and one ongoing trial investigating the effect of long-term beta-blocker therapy.

AUTHORS' CONCLUSIONS

Our present review indicates that beta-blockers for suspected or diagnosed acute myocardial infarction probably reduce the short-term risk of a reinfarction and the long-term risk of all-cause mortality and cardiovascular mortality. Nevertheless, it is most likely that beta-blockers have little or no effect on the short-term risk of all-cause mortality and cardiovascular mortality. Regarding all remaining outcomes (serious adverse events according to ICH-GCP, major adverse cardiovascular events (composite of cardiovascular mortality and non-fatal myocardial infarction during follow-up), the long-term risk of a reinfarction during follow-up, quality of life, and angina), further information is needed to confirm or reject the clinical effects of beta-blockers on these outcomes for people with or suspected of acute myocardial infarction.

Association of β-Blocker Use With Heart Failure Hospitalizations and Cardiovascular Disease Mortality Among Patients With Heart Failure With a Preserved Ejection Fraction: A Secondary Analysis of the TOPCAT Trial

IMPORTANCE

β-Blockers are prescribed to most patients with heart failure (HF) with a preserved ejection fraction (HFpEF), but their effect on HFpEF remains unclear.

OBJECTIVE

To determine the association of β-blocker use with HF hospitalizations and cardiovascular disease (CVD) mortality, overall and in strata of patients with an ejection fraction (EF) of 50% or greater or less than 50%.

DESIGN, SETTING, AND PARTICIPANTS

For 1761 participants from North and South America enrolled in the multicenter, double-blinded Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist randomized clinical trial of spironolactone for patients with HFpEF between August 10, 2006, and January 31, 2012, the association of baseline β-blocker use with HF hospitalization and CVD mortality was analyzed using unadjusted and adjusted Cox proportional hazards regression models, overall and in strata of patients with an EF of 50% or greater or less than 50%. Participants had symptomatic HF with a left ventricular EF of 45% or greater, with enrollment based on either hospitalization attributed to decompensated HF in the prior year or elevated natriuretic peptide levels. Statistical analysis was performed from January 31 to May 2, 2019.

EXPOSURE

Use of β-blockers.

MAIN OUTCOMES AND MEASURES

Incident HF hospitalization and CVD mortality.

RESULTS

Among 1761 participants included in the analysis (879 women and 882 men; mean [SD] age, 71.5 [9.6] years), 1394 (79.2%) reported β-blocker use and 1567 (89.0%) had an EF of 50% or greater. Hospitalizations for HF occurred for 399 participants (22.7%), and CVD mortality occurred for 229 participants (13.0%). Use of β-blockers was associated with a higher risk of HF hospitalization among patients with HFpEF with an EF of 50% or greater (hazard ratio, 1.74 [95% CI, 1.28-2.37]; P < .001) but not among patients with an EF between 45% and 49% (hazard ratio, 0.68 [95% CI, 0.28-1.63]; P = .39). There was a significant interaction between β-blocker use and EF threshold for incident HF hospitalizations (P = .03). Use of β-blockers was not associated with a change in CVD mortality.

CONCLUSIONS AND RELEVANCE

For patients with an EF of 50% or greater, β-blocker use was associated with an increased risk of HF hospitalizations but not CVD mortality. For patients with an EF between 45% and 49%, there was no such association.

Prevalence and association of medication nonadherence with major adverse cardiovascular events in patients with myocardial infarction

Current study was to evaluate the prevalence of guideline recommended medications adherence in myocardial infarction (MI) patients postpercutaneous coronary intervention (PCI) and the association of medication nonadherence and major adverse cardiovascular events (MACEs).MI patients who underwent PCI in the last 12 months were enrolled. Demographic and clinical characteristics were collected and guideline recommended medications were evaluated. Patients were divided into with and without MACEs groups.Compared to patients without MACEs, those with MACEs were older (54.8 ± 16.4 vs 51.1 ± 15.2 years), more likely to be smoker (40.2% vs 31.9%), have higher body mass index (BMI; 25.0 ± 6.1 vs 23.8 ± 5.7 kg/m), diabetes (47.5% vs 37.8%), ischemic stroke (34.4% vs 25.6%), and estimated lower glomerular filtration rate (85.4 ± 9.6 vs 92.6 ± 10.7 mL/minute/1.73 m). Patients with MACEs were also more likely to present with ST-elevation MI (STEMI; 54.1% vs 48.4%) and to undergo urgent PCI (62.3% vs 56.3%). Furthermore, patients with MACEs were less likely to adhere to dual antiplatelet therapy (77.9% vs 85.9%), renin-angiotensin system inhibitor (62.3% vs 69.7%), and beta-blocker (69.7% vs 72.8%) treatment. In unadjusted model, medication nonadherence was associated with 2-fold higher odds of MACEs. After adjustment for demographics, risk factors, comorbidities, and peri-PCI characteristics, medications nonadherence remained independently associated with MACEs, with odds ratio of 1.40 (95% confidence interval: 1.29-1.87).Medications adherence rate among MI patients post-PCI is suboptimal in China, which is independently associated with MACEs.

Adrenergic Downregulation in Critical Care: Molecular Mechanisms and Therapeutic Evidence

Catecholamines remain the mainstay of therapy for acute cardiovascular dysfunction. However, adrenergic receptors quickly undergo desensitization and downregulation after prolonged stimulation. Moreover, prolonged exposure to high circulating catecholamines levels is associated with several adverse effects on different organ systems. Unfortunately, in critically ill patients, adrenergic downregulation translates into progressive reduction of cardiovascular response to exogenous catecholamine administration, leading to refractory shock. Accordingly, there has been a growing interest in recent years toward use of noncatecholaminergic inotropes and vasopressors. Several studies investigating a wide variety of catecholamine-sparing strategies (eg, levosimendan, vasopressin, β-blockers, steroids, and use of mechanical circulatory support) have been published recently. Use of these agents was associated with improvement in hemodynamics and decreased catecholamine use but without a clear beneficial effect on major clinical outcomes. Accordingly, additional research is needed to define the optimal management of catecholamine-resistant shock.

Effects of a Higher Heart Rate on Quality of Life and Functional Capacity in Patients With Left Ventricular Diastolic Dysfunction

There is no evidence-based treatment for heart failure with preserved ejection fraction. Although lower heart rates (HRs) provide an unequivocal benefit for patients with HF with reduced ejection fraction, higher HR might convey important hemodynamic and substrate-modifying benefits in patients with diastolic dysfunction. In a prospective study of 20 stable outpatients with diastolic dysfunction and pacemakers, we evaluated the effects of a 4-week increase in the lower pacemaker rate to 80 beats/min followed by reversal to the previous lower HR setting from weeks 4 to 6. We assessed quality of life (Minnesota Living with Heart Failure Questionnaire), 6-minute walk test and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels. Pacing at 80 beats/min significantly improved quality of life and the 6-minute walk test (p ≤0.05). There was a strong positive correlation between the pacing-induced changes in NT-proBNP and baseline QRS intervals (r² = 0.31, p <0.01). Stratification by QRS duration revealed that pacing at 80 beats/min led to -21 ± 26% reduction in NT-proBNP in patients with QRS ≤150 ms, whereas QRS >150 ms was associated with a 26 ± 35% increase in NT-proBNP (p <0.01). Patients physiologically paced from the conduction system had a -46 ± 26% reduction in NT-proBNP at 80 beats/min as compared with 4 ± 26% and 13 ± 26% change with pacing from the right atrial appendage and right ventricular apical septum (p_interaction = 0.04). In conclusion, increasing the lower rate setting of pacemakers to 80 beats/min in patients with diastolic dysfunction improves quality of life, functional capacity, and NT-proBNP for those patients with a baseline QRS ≤150 ms. These findings suggest that higher HRs may provide meaningful benefits to patients with left ventricular diastolic dysfunction and heart failure with preserved ejection fraction.

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.

Doses of renin-angiotensin system inhibitors but not beta-blockers predict outcome after ST-elevation myocardial infarction

Objectives: In patients with ST-elevation myocardial infarction (STEMI), it is not clear whether low-dose renin-angiotensin system inhibitors and beta-blockers can result in the same benefits achievable with higher target doses. This observational study aims to investigate whether higher doses of angiotensin converting enzyme inhibitors (ACEI)/angiotensin II receptor blockers (ARB) and beta-blockers can improve outcomes in patients with STEMI. Methods: We recorded daily doses of ACEI, ARB, and beta-blockers in 331 patients with STEMI. Echocardiographic studies were performed at baseline and were repeated 6 months later. Clinical events, including all-cause death and heart failure, were followed for 2 years. Results: Patients receiving high-dose ACEI/ARB had less increase in left ventricular end-diastolic volume index (LVEDVI) at 6 months. In multivariable linear regression model, ACEI/ARB dose or beta-blocker dose was not an independent predictor of increase in LVEDVI at 6 months. Kaplan-Meier survival curves showed that doses of ACEI/ARB (p = 0.003) and beta-blockers (p = 0.027) were significant predictors of death and heart failure. In multivariable Cox regression analysis, independent predictors of all-cause death and heart failure were diabetes mellitus (p = 0.001), left ventricular ejection fraction (p = 0.026), and ACEI/ARB dose (p = 0.025). Beta-blockers dose was not a predictor of clinical events in multivariable analysis (p = 0.413). Conclusion: High-dose ACEI/ARB, but not beta-blocker, was associated with lower rate of all-cause death and heart failure in patients with STEMI.

Cost-effectiveness of a fixed-dose combination pill for secondary prevention of cardiovascular disease in China, India, Mexico, Nigeria, and South Africa: a modelling study

BACKGROUND

Fewer than 25% of patients with atherosclerotic cardiovascular disease in countries of low and middle income (LMICs) use guideline-directed drugs for secondary prevention. A fixed-dose combination polypill might improve cardiovascular outcomes by increasing prescription rates and adherence, but the cost-effectiveness of this approach is uncertain.

METHODS

We developed microsimulation models to assess the cost-effectiveness of a polypill containing aspirin, lisinopril, atenolol, and simvastatin for secondary prevention of atherosclerotic cardiovascular disease compared with current care in China, India, Mexico, Nigeria, and South Africa. We modelled baseline use of secondary prevention drugs on the Prospective Urban Rural Epidemiological study. In the intervention arm, we assumed that patients currently prescribed any prevention drug for atherosclerotic cardiovascular disease would receive the polypill instead, which would improve adherence by 32% (from a meta-analysis of two randomised trials in LMICs). We assessed the cost-effectiveness of the polypill at prices in the public sector and on the retail market. Key outcomes were major adverse cardiovascular events (cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke) over a 5-year period and the incremental cost-effectiveness ratio (ICER) from the perspective of the health-care sector and a lifetime analytical horizon. We assumed a cost-effectiveness threshold equal to each country's per capita gross domestic product (GDP) per disability-adjusted life-year (DALY) averted. In sensitivity analyses, we examined the population health effect achievable by increasing the uptake of the polypill in the eligible population.

FINDINGS

Among adults aged 30-84 years with established atherosclerotic cardiovascular disease, adoption of the polypill for secondary prevention compared with current care was projected to avert 40-54 major adverse cardiovascular events for every 1000 patients treated for 5 years and produce between three and ten additional serious adverse events. Assuming public-sector pharmaceutical prices, the ICER of the polypill compared with current care over a lifetime analytical horizon was Int$168 (95% UI 55 to 337) per DALY averted in China, $154 (57 to 289) in India, $88 (15 to 193) in Mexico, $364 (147 to 692) in Nigeria, and $64 (cost-saving to 203) in South Africa, amounting to 0·4-6·2% of the per capita GDP in these countries. The ICER of the polypill compared with current care increased to 3·3-14·6% of the per capita GDP at retail market pharmaceutical prices. Use of the polypill at current rates of prescription of secondary prevention drugs would produce modest health benefits, reducing DALYs from atherosclerotic cardiovascular disease among patients with established disease by 3·1-10·1% over 10 years. Increasing use to 50% or 75% of the eligible population would produce substantially larger health gains (up to 24·3% atherosclerotic cardiovascular disease DALYs averted).

INTERPRETATION

The polypill is projected to be cost-effective compared with current care for secondary prevention of atherosclerotic cardiovascular disease in China, India, Mexico, Nigeria, and South Africa, particularly if it is made available at public-sector pricing. However, achieving meaningful improvements in cardiovascular health will require simultaneous investments in health infrastructure to increase the uptake of the polypill among patients with established atherosclerotic cardiovascular disease.

FUNDING

Richard A and Susan F Smith Center for Outcomes Research in Cardiology, Hellman Family Foundation, Department of Veterans Affairs, and University of California at San Francisco.

De-escalation of antianginal medications after successful chronic total occlusion percutaneous coronary intervention: Frequency and relationship with health status

BACKGROUND

Successful chronic total occlusion (CTO) percutaneous coronary intervention (PCI) can markedly reduce angina symptom burden, but many patients often remain on multiple antianginal medications (AAMs) after the procedure. It is unclear when, or if, AAMs can be de-escalated to prevent adverse effects or limit polypharmacy. We examined the association of de-escalation of AAMs after CTO PCI with long-term health status.

METHODS

In a 12-center registry of consecutive CTO PCI patients, health status was assessed at 6 months after successful CTO PCI with the Seattle Angina Questionnaire and the Rose Dyspnea Scale. Among patients with technical CTO PCI success, we examined the association of AAM de-escalation with 6-month health status using multivariable models adjusting for revascularization completeness and predicted risk of post-PCI angina (using a validated risk model). We also examined predictors and variability of AAMs de-escalation.

RESULTS

Of 669 patients with technical success of CTO PCI, AAMs were de-escalated in 276 (35.9%) patients at 1 month. Patients with AAM de-escalation reported similar angina and dyspnea rates at 6 months compared with those whose AAMs were reduced (any angina: 22.5% vs 20%, P = .43; any dyspnea: 51.8% vs 50.1%, P = .40). In a multivariable model adjusting for complete revascularization and predicted risk of post-PCI angina, de-escalation of AAMs at 1 month was not associated with an increased risk of angina, dyspnea, or worse health status at 6 months.

CONCLUSIONS

Among patients with successful CTO PCI, de-escalation of AAMs occurred in about one-third of patients at 1 month and was not associated with worse long-term health status.

Misconceptions and Facts About Beta-Blockers

Beta-blockers are commonly used medications, and they have been traditionally considered "cardioprotective." Their clinical use appears to be more widespread than the available evidence base supporting their role in cardioprotection. Beta-blockers counteract neurohumoral activation in heart failure with reduced ejection fraction and offer both symptomatic improvement and reduction in adverse events. On the other hand, the use of beta-blockers in uncomplicated hypertension results in suboptimal outcomes compared to the established first-line antihypertensive agents. Providers at all levels should be familiar with common misconceptions regarding beta-blocker use in routine clinical practice.

Stable Angina Medical Therapy Management Guidelines: A Critical Review of Guidelines from the European Society of Cardiology and National Institute for Health and Care Excellence

Most patients with stable angina can be managed with lifestyle changes, especially smoking cessation and regular exercise, along with taking antianginal drugs. Randomised controlled trials show that antianginal drugs are equally effective and none of them reduced mortality or the risk of MI, yet guidelines prefer the use of beta-blockers and calcium channel blockers as a first-line treatment. The European Society of Cardiology guidelines for the management of stable coronary artery disease provide classes of recommendation with levels of evidence that are well defined. The National Institute for Health and Care Excellence (NICE) guidelines for the management of stable angina provide guidelines based on cost and effectiveness using the terms first-line and second-line therapy. Both guidelines recommend using low-dose aspirin and statins as disease-modifying agents. The aim of this article is to critically appraise the guidelines’ pharmacological recommendations for managing patients with stable angina.

Admission Heart Rate Is a Determinant of Effectiveness of Beta-Blockers in Acute Myocardial Infarction Patients

BACKGROUND

Beta-blockers are standard therapy for acute myocardial infarction (AMI). However, despite current advances in the management of AMI, it remains unclear whether all AMI patients benefit from β-blockers. We investigated whether admission heart rate (HR) is a determinant of the effectiveness of β-blockers for AMI patients.

METHODS AND RESULTS

We enrolled 3,283 consecutive AMI patients who were admitted to 28 participating institutions in the Japanese Registry of Acute Myocardial Infarction Diagnosed by Universal Definition (J-MINUET) study. According to admission HR, we divided patients into 3 groups: bradycardia (HR <60 beats/min, n=444), normocardia (HR 60 to ≤100 beats/min, n=2,013), and tachycardia (HR >100 beats/min, n=342). The primary endpoint was major adverse cardiac events (MACE), including all-cause death, non-fatal MI, non-fatal stroke, heart failure (HF), and urgent revascularization for unstable angina, at 3-year follow-up. Beta-blocker at discharge was significantly associated with a lower risk of MACE in the tachycardia group (23.6% vs. 33.0%; P=0.033), but it did not affect rates of MACE in the normocardia group (17.8% vs. 18.4%; P=0.681). In the bradycardia group, β-blocker use at discharge was significantly associated with a higher risk of MACE (21.6% vs. 12.7%; P=0.026). Results were consistent for multivariable regression and stepwise multivariable regression.

CONCLUSIONS

Admission HR might determine the efficacy of β-blockers for current AMI patients.

Angina and left ventricular dysfunction: can we 'reduce' it?

Despite the evolution in pharmacology and devices, recurrent and persistent angina still represent a frequent issue in clinical practice. A 69-year-old Caucasian female patient has history of surgical aortic valve replacement with a bioprosthesis for severe aortic stenosis with subsequent transcatheter valve-in-valve implantation for bioprosthesis degeneration and single coronary artery bypass graft with left internal mammary artery on left anterior descending (LAD). After transcatheter aortic valve implantation, she started to complain angina [Canadian Cardiovascular Society (CCS) Class III], effectively treated with bisoprolol uptitration and ivabradine 5 b.i.d. addition. After 6 months, she had a non-ST segment elevated myocardial infarction with evidence of left main occlusion and good functioning aortic bioprosthesis. A retrograde drug-eluting balloon percutaneous coronary intervention (PCI) on LAD (in-stent restenosis) was performed. However, the patient continued to complain angina (CCS Class II-III), even after further ivabradine increase to 7.5 mg b.i.d. After 4 months, the patient underwent Reducer implantation. After 2 months, angina started to improve and the patient is currently angina free. In the last decades, PCI materials and stents greatly improved. Medical therapy (such as β-blockers) has been shown not only to improve symptoms but also to add a prognostic benefit in patients with reduced ejection fraction (EF). Ivabradine showed additional benefits in patients with angina and reduced EF. However, still a relevant portion of patients complain refractory angina. The COSIRA trial showed that a coronary sinus Reducer was associated with greater angina relief than the sham procedure and could be a further step in angina treatment.

Effect of oral β-blocker treatment on mortality in contemporary post-myocardial infarction patients: a systematic review and meta-analysis

Aims

Guidelines concerning β-blocker treatment following acute myocardial infarction (AMI) are based on studies undertaken before the implementation of reperfusion and secondary prevention therapies. We aimed to estimate the effect of oral β-blockers on mortality in contemporary post-AMI patients with low prevalence of heart failure and/or reduced left ventricular ejection fraction.

Methods and results

A random effects model was used to synthetize results of 16 observational studies published between 1 January 2000 and 30 October 2017. Publication bias was evaluated, and heterogeneity between studies examined by subgroup and random effects meta-regression analyses considering patient-related and study-level variables. The pooled estimate showed that β-blocker treatment [among 164 408 (86.8%) patients, with median follow-up time of 2.7 years] was associated with a 26% reduction in all-cause mortality [rate ratio (RR) 0.74, 95% confidence interval (CI) 0.64–0.85] with moderate heterogeneity (I² = 67.4%). The patient-level variable mean age of the cohort explained 31.5% of between study heterogeneity. There was presence of publication bias, or small study effect, and when controlling for bias by the trim and fill simulation method, the effect disappeared (adjusted RR 0.90, 95% CI 0.77–1.04). Also, small study effect was demonstrated by a cumulative meta-analysis starting with the largest study showing no effect, with increasing effect as the smaller studies were accumulated.

Conclusion

Evidence from this study suggests that there is no association between β-blockers and all-cause mortality. A possible beneficial effect in AMI survivors needs to be tested by large randomized clinical trials.

Beta-blockers for post-acute coronary syndrome mid-range ejection fraction: a nationwide retrospective study

BACKGROUND

Patients with mid-range ejection fraction (40-49%) are in focus due to the newly defined entity of heart failure with mid-range ejection fraction. Acute coronary syndromes are a major aetiology for heart failure with mid-range ejection fraction. We aim to evaluate which therapeutic decisions are associated with inhospital survival benefit in post-acute coronary syndrome patients categorised according to the ejection fraction.

METHODS AND RESULTS

The authors analysed a cohort of a multicentre national registry enrolling acute coronary syndrome patients between 2010 and 2016, classified according to their ejection fraction before hospital discharge. Patients with previously known heart failure or with no ejection fraction evaluation were excluded. A total of 9429 patients were included and categorised in three groups: (a) ejection fraction of 50% or greater (n=6113, 65%); (b) ejection fraction of 40-49% (n=1926, 20%); and (c) ejection fraction less than 40% (n=1390, 15%). The primary endpoint was inhospital mortality. To eliminate confounding factors, a multivariate logistic regression analysis was conducted, including acute coronary syndrome type, baseline characteristics, pharmacological treatment, clinical data, laboratory data and coronary anatomy when known. The overall inhospital mortality was 2.8% (n=263): 0.9% (n=53) in group 1, 2.4% (n=37) in group 2 and 11.4% (n=159) in group 3. After multivariate analysis, an invasive strategy had a positive impact in all groups, inhospital beta-blocker administration had a positive impact for groups 2 and 3, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker and spironolactone had a positive impact on group 3.

CONCLUSION

Post-acute coronary syndrome mid-range ejection fraction patients represent an intermediate risk group in which beta-blocker administration was associated with inhospital survival benefit. An invasive strategy was a survival predictor for all groups, regardless of ejection fraction category.

BEtablocker Treatment After acute Myocardial Infarction in revascularized patients without reduced left ventricular ejection fraction (BETAMI): Rationale and design of a prospective, randomized, open, blinded end point study

BACKGROUND

Current guidelines on the use of β-blockers in post-acute myocardial infarction (MI) patients without reduced left ventricular ejection fraction (LVEF) are based on studies before the implementation of modern reperfusion and secondary prevention therapies. It remains unknown whether β-blockers will reduce mortality and recurrent MI in contemporary revascularized post-MI patients without reduced LVEF.

DESIGN

BETAMI is a prospective, randomized, open, blinded end point multicenter study in 10,000 MI patients designed to test the superiority of oral β-blocker therapy compared to no β-blocker therapy. Patients with LVEF ≥40% following treatment with percutaneous coronary intervention or thrombolysis and/or no clinical signs of heart failure are eligible to participate. The primary end point is a composite of all-cause mortality or recurrent MI obtained from national registries over a mean follow-up period of 3 years. Safety end points include rates of nonfatal MI, all-cause mortality, ventricular arrhythmias, and hospitalizations for heart failure obtained from hospital medical records 30 days after randomization, and from national registries after 6 and 18 months. Key secondary end points include recurrent MI, heart failure, cardiovascular and all-cause mortality, and clinical outcomes linked to β-blocker therapy including drug adherence, adverse effects, cardiovascular risk factors, psychosocial factors, and health economy. Statistical analyses will be conducted according to the intention-to-treat principle. A prespecified per-protocol analysis (patients truly on β-blockers or not) will also be conducted.

CONCLUSIONS

The results from the BETAMI trial may have the potential of changing current clinical practice for treatment with β-blockers following MI in patients without reduced LVEF. EudraCT number 2018-000590-75.

Prognostic Impact of β-Blocker Dose After Acute Myocardial Infarction

BACKGROUND

The differential prognostic impact of β-blocker dose after acute myocardial infarction (AMI) has been under debate. The current study sought to compare clinical outcome after AMI according to β-blocker dose using the Korea Acute Myocardial Infarction Registry-National Institutes of Health (KAMIR-NIH).

METHODS AND RESULTS

Of the total population of 13,104 consecutive AMI patients enrolled in the KAMIR-NIH, the current study analyzed 11,909 patients. These patients were classified into 3 groups (no β-blocker; low-dose [<25% of target dose]; and high-dose [≥25% of target dose]). The primary outcome was cardiac death at 1 year. Compared with the no β-blocker group, both the low-dose and high-dose groups had significantly lower risk of cardiac death (HR, 0.435; 95% CI: 0.363-0.521, P<0.001; HR, 0.519; 95% CI: 0.350-0.772, P=0.001, respectively). The risk of cardiac death, however, was similar between the high- and low-dose groups (HR, 1.194; 95% CI: 0.789-1.808, P=0.402). On multivariable adjustment and inverse probability weighted analysis, the result was the same.

CONCLUSIONS

The use of β-blockers in post-AMI patients had significant survival benefit compared with no use of β-blockers. There was no significant additional benefit of high-dose β-blockers compared with low-dose β-blockers, however, in terms of 1-year risk of cardiac death.

Preoperative Management of Medications

Increasingly complex medication regimens for many comorbidities in patients for planned surgical and procedural interventions necessitate detailed preoperative evaluation of the pharmacologic therapy, including the indications, the specific drugs, and dosing amount and interval. The implications of continuing or withholding these agents in the perioperative period need to be elucidated, as well as the risks of interactions and side effects. A comprehensive plan of the management of the therapeutic agents should be devised during the preoperative visit, with input from all relevant specialists, and clearly communicated to the patients in a format that ensures their comprehension and consistent compliance.

Sympathetic overactivity in dialysis patients-Underappreciated and clinically consequential

Cardiovascular morbidity and mortality remain frustratingly common in dialysis patients. A dearth of established evidence-based treatment calls for alternative therapeutic avenues to be embraced. Sympathetic hyperactivity, predominantly due to afferent nerve signaling from the diseased native kidneys, has been established to be prognostic in the dialysis population for over 15 years. Despite this, tangible therapeutic interventions have, to date, been unsuccessful and the outlook for patients remains poor. This narrative review summarizes established experimental and clinical data, highlighting recent developments, and proposes why interventions to ameliorate sympathetic hyperactivity may well be beneficial for this high-risk population.

Through the Decades: β-Blocker Use and Outcomes in Acute Coronary Syndromes

Beta-adrenergic receptor antagonists, or β-blockers, have been a cornerstone of treatment in patients with acute coronary syndromes (ACS) for more than 4 decades. First studied in the 1960s, β-blockers in ACS have been shown to decrease the risk of death, recurrent ischemic events, and arrhythmias by reducing catecholamine-mediated effects and reducing myocardial oxygen demand. Through the decades, the β-blocker of choice, timing of initiation, duration of therapy, and dosing have evolved considerably. Despite having clear benefits in certain patient populations (eg, patients with systolic dysfunction who are hemodynamically stable), the benefit of β-blockers in other populations (ie, in patients at low risk for complications receiving modern revascularization therapies and optimal medical management) remains unclear. This article provides a review of the landmark clinical trials of β-blockers in ACS and highlights the chronology and evolution of guideline recommendations through the decades.

Rationale for administering beta-blocker therapy to patients undergoing coronary artery bypass surgery: a systematic review

INTRODUCTION

Secondary preventative therapies are essential for patients undergoing coronary artery bypass graft (CABG) surgery to optimize perioperative and long-term outcomes. Beta-blockers are commonly used to treat patients with coronary artery disease and congestive heart failure (CHF), but their role for CABG patients remains unclear. The goal of this systematic review was to evaluate the rationale for administering beta-blockers to the CABG population and to assess their efficacy before and after coronary surgical revascularization.

AREAS COVERED

A systematic literature review was performed to retrieve relevant articles from the PubMed database published between 1985 and 2017.

EXPERT OPINION

Outside of the surgical field, strong evidence supports the use of beta-blockers for patients with a history of previous myocardial infarction (MI) or CHF. For the CABG population, studies have suggested that perioperative beta-blocker therapy is beneficial, with an associated reduction in mortality, particularly among those with a history of previous MI or CHF. Beta-blocker administration has also clearly been shown to lower the rate of new-onset postoperative atrial fibrillation after CABG. Among the different types of beta-blockers, perioperative carvedilol appears to be the most beneficial. In the absence of contraindications, nearly all CABG patients are candidates for perioperative beta-blocker therapy.

Pharmacological heart rate lowering in patients with a preserved ejection fraction-review of a failing concept

Epidemiological studies have demonstrated that high resting heart rates are associated with increased mortality. Clinical studies in patients with heart failure and reduced ejection fraction have shown that heart rate lowering with beta-blockers and ivabradine improves survival. It is therefore often assumed that heart rate lowering is beneficial in other patients as well. Here, we critically appraise the effects of pharmacological heart rate lowering in patients with both normal and reduced ejection fraction with an emphasis on the effects of pharmacological heart rate lowering in hypertension and heart failure. Emerging evidence from recent clinical trials and meta-analyses suggest that pharmacological heart rate lowering is not beneficial in patients with a normal or preserved ejection fraction. This has just begun to be reflected in some but not all guideline recommendations. The detrimental effects of pharmacological heart rate lowering are due to an increase in central blood pressures, higher left ventricular systolic and diastolic pressures, and increased ventricular wall stress. Therefore, we propose that heart rate lowering per se reproduces the hemodynamic effects of diastolic dysfunction and imposes an increased arterial load on the left ventricle, which combine to increase the risk of heart failure and atrial fibrillation. Pharmacologic heart rate lowering is clearly beneficial in patients with a dilated cardiomyopathy but not in patients with normal chamber dimensions and normal systolic function. These conflicting effects can be explained based on a model that considers the hemodynamic and ventricular structural effects of heart rate changes.

Treatment of Angina: Where Are We?

Ischaemic heart disease is a major cause of death and disability worldwide, while angina represents its most common symptom. It is estimated that approximately 9 million patients in the USA suffer from angina and its treatment is challenging, thus the strategy to improve the management of chronic stable angina is a priority. Angina might be the result of different pathologies, ranging from the “classical” obstruction of a large coronary artery to alteration of the microcirculation or coronary artery spasm. Current clinical guidelines recommend antianginal therapy to control symptoms, before considering coronary artery revascularization. In the current guidelines, drugs are classified as being first-choice (beta-blockers, calcium channel blockers, and short-acting nitrates) or second-choice (ivabradine, nicorandil, ranolazine, trimetazidine) treatment, with the recommendation to reserve second-line modifications for patients who have contraindications to first-choice agents, do not tolerate them, or remain symptomatic. However, such a categorical approach is currently questioned. In addition, current guidelines provide few suggestions to guide the choice of drugs more suitable according to the underlying pathology or the patient comorbidities. Several other questions have recently emerged, such as: is there evidence-based data between first- and second-line treatments in terms of prognosis or symptom relief? Actually, it seems that newer antianginal drugs, which are classified as second choice, have more evidence-based clinical data that are more contemporary to support their use than what is available for the first-choice drugs. It follows that actual guidelines are based more on tradition than on evidence and there is a need for new algorithms that are more individualized to patients, their comorbidities, and pathophysiological mechanism of chronic stable angina.

Registry-based randomised clinical trial: efficient evaluation of generic pharmacotherapies in the contemporary era

Randomised clinical trials are the gold standard for testing the effectiveness of clinical interventions. However, increasing complexity and associated costs may limit their application in the investigation of key cardiovascular knowledge gaps such as the re-evaluation of generic pharmacotherapies. The registry-based randomised clinical trial (RRCT) leverages data sampling from nationwide quality registries to facilitate high participant inclusion rates at comparably low costs and, therefore, may offer a mechanism by which such clinical questions may be answered. To date, a number of studies have been conducted using such trial designs, but uncritical use of the RRCT design may lead to erroneous conclusions. The current review provides insights into the strengths and weaknesses of the RRCT, as well as provides an exploratory example of how a trial may be designed to test the long-term effectiveness of beta blockers in patients with myocardial infarction who have preserved left ventricular systolic function.

Risk of All-Cause Mortality in Diabetic Patients Taking β-Blockers

OBJECTIVE

To assess the relationship between use of β-blockers and all-cause mortality in patients with and without diabetes.

PATIENTS AND METHODS

Using data from the US National Health and Nutrition Examination Survey 1999-2010, we conducted a prospective cohort study. The study participants were followed-up from the survey participation date until December 31, 2011. We used a Cox proportional hazards model for all-cause mortality analysis. The multivariate-adjusted hazard ratios (HRs) of the participants taking β-blockers were compared with those of the participants not taking β-blockers.

RESULTS

This study included 2840 diabetic participants and 14,684 nondiabetic participants. Compared with diabetic participants not taking a β-blocker, all-cause mortality was significantly higher in diabetic participants taking any β-blocker (HR, 1.49; 95% CI, 1.09-2.04; P=.01), taking a β₁-selective β-blocker (HR, 1.60; 95% CI, 1.13-2.24; P=.007), or taking a specific β-blocker (bisoprolol, metoprolol, and carvedilol) (HR, 1.55; 95% CI, 1.09-2.21; P=.01). In addition, all-cause mortality in diabetic participants with coronary heart disease (CHD) was significantly higher in those taking beta-blockers, compared with those not taking beta-blockers (HR, 1.64; 95% CI, 1.08-2.48; P=.02), whereas that in non-diabetic participants with CHD was significantly lower in those taking beta-blockers (HR, 0.68; 95% CI, 0.50-0.94; P=.02). A propensity score-matched Cox proportional hazards model yielded similar results.

CONCLUSION

Use of β-blockers may be associated with an increased risk of mortality for patients with diabetes and among the subset who have CHD.

Clinical Events After Discontinuation of β‐Blockers in Patients Without Heart Failure Optimally Treated After Acute Myocardial Infarction

Background:

β-blockers have been among the first medications shown to improve outcomes after acute myocardial infarction (AMI). With the advent of reperfusion therapy and other secondary-prevention medications, their role has become uncertain, and large-scale experience after AMI in the contemporary era is lacking. In particular, the effect of stopping β-blockers in patients initially treated after AMI is unknown.

Methods and Results:

Using the French healthcare databases, 73 450 patients (<80 years of age), admitted for AMI in 2007 to 2012, without acute coronary syndrome (ACS) in the previous 2 years and no evidence of heart failure, having received optimal treatment with myocardial revascularization and all recommended medications in the 4 months after index admission, and not having discontinued β-blockers before 1 year, were followed for 3.8 years on average. β-Blocker discontinuation was defined as 4 consecutive months without exposure. If β-blocker treatment was resumed later on, follow-up was stopped. Both the risk of the composite outcome of death or admission for ACS and the risk of all-cause mortality were assessed in relation with β-blocker discontinuation during follow-up. Adjusted hazard ratios were estimated using marginal structural models accounting for time-varying confounders affected by previous exposure. A similar analysis was performed with statins. Of 204 592 patient-years, 12 002 (5.9%) corresponded to discontinued β-blocker treatment. For β-blocker discontinuation, the adjusted hazard ratio for death or ACS was 1.17 (95% confidence interval, 1.01–1.35); for all-cause death, the adjusted hazard ratio was 1.13 (95% confidence interval, 0.94–1.36). In contrast, for statin discontinuation, the adjusted hazard ratios for death or ACS and for all-cause death were 2.31 (95% confidence interval, 2.01–2.65) and 2.57 (95% confidence interval, 2.19–3.02), respectively.

Conclusions:

In routine care of patients without heart failure, revascularized and optimally treated after AMI, discontinuation of β-blockers beyond 1 year after AMI was associated with an increased risk of death or readmission for ACS, while statistical significance was not reached for the association with all-cause mortality. A contemporary randomized clinical trial is needed to precise the role of β-blockers in the long-term treatment after AMI.

Current use of beta-blockers in patients with coronary artery disease

Beta-blockers have long comprised a cornerstone in the symptomatic treatment of ischemic heart disease and in the secondary prevention of myocardial infarction and heart failure. The majority of studies underlying the evidence of a beneficial effect of beta-blockers on outcomes were conducted more than 25 years ago. In a contemporary era where treatment strategies and secondary prophylactic therapy have undergone several changes, the continued role of beta-blockers in ischemic heart disease has been questioned, especially in the absence of heart failure or a recent myocardial infarction. In summary, few randomized clinical trials are available on the effect of beta-blockers in the reperfusion era, especially on hard endpoints. Likewise, the results of numerous observational studies and meta-analysis are conflicting, emphasizing the need for additional large-scale randomized clinical trials to evaluate the role of beta-blocker therapy in current clinical practice.

β-Blocker Therapy Prior to Admission for Acute Coronary Syndrome in Patients Without Heart Failure or Left Ventricular Dysfunction Improves In-Hospital and 12-Month Outcome: Results From the GULF-RACE 2 (Gulf Registry of Acute Coronary Events-2)

BACKGROUND

The prognostic impact of β-blockers (BB) in acute coronary syndrome (ACS) patients without heart failure (HF) or left ventricular dysfunction is controversial, especially in the postreperfusion era. We sought to determine whether a BB therapy before admission for ACS has a favorable in-hospital outcome in patients without HF, and whether they also reduce 12-month mortality if still prescribed on discharge.

METHODS AND RESULTS

The GULF-RACE 2 (Gulf Registry of Acute Coronary Events-2) is a prospective multicenter study of ACS in 6 Middle Eastern countries. We studied in-hospital cardiovascular events in patients hospitalized for ACS without HF in relation to BB on admission, and 1-year mortality in relation to BB on discharge. Among the 7903 participants, 7407 did not have HF, of whom 5937 (80.15%) patients were on BB. Patients on BB tended to be older and have more comorbidities. However, they had a lower risk of in-hospital mortality, mitral regurgitation, HF, cardiogenic shock, and ventricular tachycardia/ventricular fibrillation. Furthermore, 4208 patients were discharged alive and had an ejection fraction ≥40%. Among those, 84.1% had a BB prescription. At 12 months, they also had a reduced risk of mortality as compared with the non-BB group. Even after correcting for confounding factors in 2 different models, in-hospital and 12-month mortality risk was still lower in the BB group.

CONCLUSIONS

In this cohort of ACS, BB therapy before admission for ACS is associated with decreased in-hospital mortality and major cardiovascular events, and 1-year mortality in patients without HF or left ventricular dysfunction if still prescribed on discharge.

Heart rate recovery of individuals undergoing cardiac rehabilitation after acute coronary syndrome

BACKGROUND

An efficient cardiac rehabilitation programme (CRP) can improve the functional ability of patients after acute coronary syndrome (ACS).

OBJECTIVE

To examine the effect of a CRP on parasympathetic reactivation and heart rate recovery (HRR) measured after a 6-min walk test (6MWT), and correlation with 6MWT distance and well-being after ACS.

METHODS

Eleven normoweight patients after ACS (BMI<25kg/m²; 10 males; mean [SD] age 61 [9] years) underwent an 8-week CRP. Before (pre-) and at weeks 4 (W4) and 8 (W8) during the CRP, they performed a 6MWT on a treadmill, followed by 10-min of seated passive recovery, with HRR and HR variability (HRV) recordings. HRR was measured at 1, 3, 5 and 10min after the 6MWT (HRR1, HRR3, HRR5, HRR10), then modelized by a mono-exponential function. Time-domain (square root of the mean of the sum of the squares of differences between adjacent normal R-R intervals [RMSSD]) and frequency-domain (with high- and low-frequency band powers) were used to analyse HRV. Participants completed a mental and physical well-being questionnaire at pre- and W8. Exhaustion after tests was assessed by the Borg scale. Pearson correlation was used to assess correlations.

RESULTS

HRR3, HRR5 and HRR10 increased by 37%, 36% and 28%, respectively, between pre- and W8 (P<0.05), and were positively correlated with change in 6MWT distance (r=0.58, 0.66 and 0.76; P<0.05). Percentage change in HRR3 was positively correlated with change in well-being (r=0.70; P=0.01). Parasympathic reactivation (RMSSD) was improved only during the first 30sec of recovery (P=0.04).

CONCLUSION

Among patients undergoing a CRP after ACS, increased HRR after a 6MWT, especially at 3min, was positively correlated with 6MWT distance and improved well-being. HRR raw data seem more sensitive than post-exercise HRV analysis for monitoring functional and autonomic improvement after ACS.

Meta-Analysis Comparing Metoprolol and Carvedilol on Mortality Benefits in Patients With Acute Myocardial Infarction

Although carvedilol, a nonselective beta-blocker with alpha-adrenergic blocking and multiple ancillary activities, has been demonstrated to be superior to metoprolol in chronic heart failure, it remains unclear whether the superiority of carvedilol still exists in myocardial infarction (MI). Therefore, we performed a network meta-analysis of randomized controlled trials (RCTs) to compare the 2 drugs in patients with MI. All RCTs that compared either 2 of the following interventions, carvedilol, metoprolol, and placebo, for the treatment of MI were included. The Cochrane Collaboration Central Register of Controlled Trials, Embase, and PubMed were searched thoroughly for potential eligible studies. Finally, 12 RCTs involving 61,081 patients were included. Pooled results showed that compared with placebo, carvedilol and metoprolol significantly reduced composite cardiovascular events (risk ratio [RR] 0.63; 95% credible interval [CrI] 0.41, 0.85 for carvedilol; RR 0.78; 95% CrI 0.65, 0.93 for metoprolol) and re-infarction (RR 0.57; 95% CrI 0.37, 0.84 for carvedilol; RR 0.77; 95% CrI 0.62, 0.91 for metoprolol) in patients with MI. However, neither carvedilol nor metoprolol showed significant benefits on all-cause death, cardiovascular death, revascularization, and rehospitalization. Also, no obvious difference was found when comparing carvedilol and metoprolol on primary or secondary outcomes. In conclusion, there is insufficient evidence supporting the superiority of carvedilol over metoprolol for the treatment of MI. Further studies are needed to confirm our findings.

Benefit of Vasodilating β-Blockers in Patients With Acute Myocardial Infarction After Percutaneous Coronary Intervention: Nationwide Multicenter Cohort Study

BACKGROUND

Although current guidelines recommend β-blocker after acute myocardial infarction (MI), the role of β-blocker has not been well investigated in the modern reperfusion era. In particular, the benefit of vasodilating β-blocker over conventional β-blocker is still unexplored.

METHODS AND RESULTS

Using nation-wide multicenter Korean Acute Myocardial Infarction Registry data, we analyzed clinical outcomes of 7127 patients with acute MI who underwent successful percutaneous coronary intervention with stents and took β-blockers: vasodilating β-blocker (n=3482), and conventional β-blocker (n=3645). In the whole population, incidence of cardiac death at 1 year was significantly lower in the vasodilating β-blocker group (vasodilating β-blockers versus conventional β-blockers, 1.0% versus 1.9%; P=0.003). In 2882 pairs of propensity score-matched population, the incidence of cardiac death was significantly lower in the vasodilating β-blocker group (1.1% versus 1.8%; P=0.028). Although incidences of MI (1.1% versus 1.5%; P=0.277), any revascularization (2.8% versus 3.0%; P=0.791), and hospitalization for heart failure (1.4% versus 1.9%; P=0.210) were not different between the 2 groups, incidences of cardiac death or MI (2.0% versus 3.1%; P=0.010), cardiac death, MI, or hospitalization for heart failure (3.0% versus 4.5%; P=0.003), cardiac death, MI, or any revascularization (3.9% versus 5.3%; P=0.026), and cardiac death, MI, any revascularization, or hospitalization for heart failure (4.8% versus 6.5%; P=0.011) were significantly lower in the vasodilating β-blocker group.

CONCLUSIONS

Vasodilating β-blocker therapy resulted in better clinical outcomes than conventional β-blocker therapy did in patients with acute MI in the modern reperfusion era. Vasodilating β-blockers could be recommended preferentially to conventional ones for acute MI patients.