β-Blockers in myocardial infarction and coronary artery disease with a preserved ejection fraction: recommendations, mechanisms, and concerns

Do Clinical Outcomes and Quality of Life Differ by the Number of Antianginals for Stable Ischemic Heart Disease? Insights from the BARI 2D Trial

Medical therapy, including antianginal treatment, is the cornerstone in the management of stable ischemic heart disease (SIHD). However, it remains unclear whether combining antianginal agents provides benefits beyond monotherapy in terms of quality of life (QoL) and cardiovascular outcomes. We used data from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial, which compared cardiovascular and QoL outcomes in patients with SIHD and diabetes mellitus randomized to revascularization with intensive medical therapy or intensive medical therapy alone. We categorized patients into 3 groups: ≥2 versus 1 versus 0 antianginals. We compared patient characteristics, QoL metrics, and cardiovascular end points at baseline and at 5 years, creating a multivariable model to adjust for key clinical confounders. Of 2,368 patients, 348 patients (14.7%) were on 0 antianginals, 1,020 patients (43.1%) were on 1 antianginal, and 1,000 patients (42.2%) were on ≥2 antianginals at baseline. The most common antianginal class was β blockers. At baseline, patients on 0 antianginals had better QoL metrics (self-health score, Duke activity status index, and energy rating) than patients on ≥2 antianginals. However, at the 1-year follow-up, patients taking only 1 antianginal showed greater QoL improvement than those taking 0 antianginal, without any incremental benefit in QoL metrics seen in patients taking ≥2 antianginal agents, even after adjusting for multiple covariates such as age, heart failure, diabetes control, and myocardial jeopardy index. Lastly, at the 5-year follow-up, after adjustment, there were no differences in all-cause mortality, major adverse cardiovascular events, or myocardial infarction between patients taking different numbers of antianginals. Adults on a single antianginal for SIHD and diabetes mellitus had similar or better improvements in QoL than those on 2 or more antianginal agents at 1 year of follow-up. These findings merit further research to better understand the impact of medical therapy intensity on QoL in patients with SIHD and associated co-morbidities.

Medications for specific phenotypes of heart failure with preserved ejection fraction classified by a machine learning-based clustering model

OBJECTIVE

Our previously established machine learning-based clustering model classified heart failure with preserved ejection fraction (HFpEF) into four distinct phenotypes. Given the heterogeneous pathophysiology of HFpEF, specific medications may have favourable effects in specific phenotypes of HFpEF. We aimed to assess effectiveness of medications on clinical outcomes of the four phenotypes using a real-world HFpEF registry dataset.

METHODS

This study is a posthoc analysis of the PURSUIT-HFpEF registry, a prospective, multicentre, observational study. We evaluated the clinical effectiveness of the following four types of postdischarge medication in the four different phenotypes: angiotensin-converting enzyme inhibitors (ACEi) or angiotensin-receptor blockers (ARB), beta blockers, mineralocorticoid-receptor antagonists (MRA) and statins. The primary endpoint of this study was a composite of all-cause death and heart failure hospitalisation.

RESULTS

Of 1231 patients, 1100 (83 (IQR 77, 87) years, 604 females) were eligible for analysis. Median follow-up duration was 734 (398, 1108) days. The primary endpoint occurred in 528 patients (48.0%). Cox proportional hazard models with inverse-probability-of-treatment weighting showed the following significant effectiveness of medication on the primary endpoint: MRA for phenotype 2 (weighted HR (wHR) 0.40, 95% CI 0.21 to 0.75, p=0.005); ACEi or ARB for phenotype 3 (wHR 0.66 0.48 to 0.92, p=0.014) and statin therapy for phenotype 3 (wHR 0.43 (0.21 to 0.88), p=0.020). No other medications had significant treatment effects in the four phenotypes.

CONCLUSIONS

Machine learning-based clustering may have the potential to identify populations in which specific medications may be effective. This study suggests the effectiveness of MRA, ACEi or ARB and statin for specific phenotypes of HFpEF.

TRIAL REGISTRATION NUMBER

UMIN000021831.

Physician Perspectives on the Use of Beta Blockers in Heart Failure With Preserved Ejection Fraction

β-blockers are commonly used in heart failure with preserved ejection fraction (HFpEF), even in the absence of a compelling indication and despite the potential to cause harm. Identifying reasons for β-blocker prescription in HFpEF could permit the development of strategies to reduce unnecessary use and potentially improve medication prescribing patterns in this vulnerable population. We administered an online survey regarding β-blocker prescribing behavior to physicians trained in internal medicine or geriatrics (noncardiology physicians) and to cardiologists at 2 large academic medical centers. The survey assessed the reasons for β-blocker initiation, agreement regarding initiation and/or continuation of β-blockers by another clinician, and deprescribing behavior. The response rate was 28.2% (n = 231). Among respondents, 68.2% reported initiating β-blockers in patients with HFpEF. The most common reason for initiating a β-blocker was for treatment of an atrial arrhythmia. Notably, 23.7% of physicians reported initiating a β-blocker without an evidence-based indication. When a β-blocker was considered not necessary, 40.1% of physicians reported they were rarely or never willing to deprescribe. The most common reason for not deprescribing a β-blocker when the physician felt that a β-blocker was unnecessary was the concern about interfering with another physicians' treatment plan (76.6%). In conclusion, a significant proportion of noncardiology physicians and cardiologists report prescribing β-blockers to patients with HFpEF, even when evidence-based indications are absent, and rarely deprescribe β-blockers in these scenarios.

Increased Risk of Heart Failure in Elderly Patients Treated with Beta-Blockers After AV Node Ablation

INTRODUCTION

Controversy exists regarding the indication of beta-blockers (BB) in different scenarios in patients with cardiovascular disease. We sought to evaluate the effect of BB on survival and heart failure (HF) hospitalizations in a sample of pacemaker-dependent patients after AV node ablation to control ventricular rate for atrial tachyarrhythmias.

METHODS

A retrospective study including consecutive patients that underwent AV node ablation was conducted in a single center between 2011 and 2019. The study's primary endpoints were the incidence of all-cause mortality, first HF hospitalization and the cumulative incidence of subsequent hospitalizations for HF. Competing risk analyses were employed.

RESULTS

A total of 111 patients with a mean age of 73.9 years were included in the study. After a median follow-up of 45.5 months, 43 patients had died (38.7%) and 31 had been hospitalized for HF (27.9%). The recurrent HF hospitalization rate was 74/1000 patients/year. Patients treated with BB had a non-significant trend to higher mortality rates and a higher risk of recurrent HF hospitalizations (incidence rate ratio 2.23, 95% confidence interval 1.12-4.44; p = 0.023).

CONCLUSION

After an AV node ablation, the use of BB is associated with an increased risk of HF hospitalizations in a cohort of elderly patients.

Effect of beta-blocker therapy on the response to mavacamten in patients with symptomatic obstructive hypertrophic cardiomyopathy

AIMS

In the EXPLORER-HCM trial, mavacamten improved exercise capacity and symptoms in patients with obstructive hypertrophic cardiomyopathy (oHCM). Mavacamten effects on the primary endpoint, a composite of peak oxygen consumption (VO₂ ) and New York Heart Association (NYHA) class, were greater in patients not receiving background beta-blockers than in those receiving beta-blockers. We sought to determine if the effect of background treatment was consistent across other clinically meaningful parameters.

METHODS AND RESULTS

Subgroup analyses by beta-blocker use were performed in patients with oHCM from the EXPLORER-HCM and mavacamten long-term extension (MAVA-LTE) studies. In EXPLORER-HCM, 189 patients (75.3%) were receiving beta-blockers, and 62 (24.7%) were receiving non-dihydropyridine calcium channel blockers or no background HCM medication; 170 patients (90.4%) receiving beta-blockers had chronotropic incompetence. Improvements in peak VO₂ at week 30 with mavacamten versus placebo were lower with beta-blockers (mean difference [95% confidence interval (CI)]: 1.04 [0.12, 1.95] ml/kg/min) than without beta-blockers (mean difference [95% CI]: 2.69 [1.29, 4.09] ml/kg/min); improvements in non-heart rate-dependent parameters (V_E /VCO₂ slope) appeared unaffected by beta-blockers. Improvements in functional capacity parameters at week 30 with mavacamten versus placebo were independent of beta-blockade for post-exercise left ventricular outflow tract gradient (mean difference [95% CI]: -37.9 [-48.0, -27.9] mmHg with beta-blockers; -33.5 [-53.6, -13.3] mmHg without beta-blockers), proportion of patients with reduction of ≥1 NYHA class, Kansas City Cardiomyopathy Questionnaire clinical summary scores and N-terminal pro-B-type natriuretic peptide. Mavacamten benefits were reproduced and maintained in MAVA-LTE regardless of beta-blockade.

CONCLUSION

Mavacamten improved measures of functional capacity, left ventricular outflow tract obstruction, symptom burden and biomarkers in patients with HCM regardless of beta-blocker use. Beta-blocker use was often associated with chronotropic incompetence, affecting peak VO₂ and other heart rate-dependent measures, but had minimal impact on heart rate-independent measures.

Beta-Blocker Use in Hypertension and Heart Failure (A Secondary Analysis of the Systolic Blood Pressure Intervention Trial)

Given the concern that beta-blocker use may be associated with an increased risk for heart failure (HF) in populations with normal left ventricular systolic function, we evaluated the association between beta-blocker use and incident HF events, as well as loop diuretic initiation in the Systolic Blood Pressure Intervention Trial (SPRINT). SPRINT demonstrated that a blood pressure target of <120 mm Hg reduced cardiovascular outcomes compared with <140 mm Hg in adults with at least one cardiovascular risk factor and without HF. The lower rate of the composite primary outcome in the 120 mm Hg group was primarily driven by a reduction in HF events. Subjects on a beta blocker for the entire trial duration were compared with subjects who never received a beta blocker after 1:1 propensity score matching. A competing risk survival analysis by beta-blocker status was performed to estimate the effect of the drug on incident HF and was then repeated for a secondary end point of cardiovascular disease death. Among the 3,284 propensity score-matched subjects, beta-blocker exposure was associated with an increased HF risk (hazard ratio 5.86; 95% confidence interval 2.73 to 13.04; p <0.001). A sensitivity analysis of propensity score-matched cohorts with a history of coronary artery disease or atrial fibrillation revealed the same association (hazard ratio 3.49; 95% confidence interval 1.15 to 10.06; p = 0.028). In conclusion, beta-blocker exposure in this secondary analysis was associated with increased incident HF in subjects with hypertension without HF at baseline.

Effect of beta-blocker therapy in patients with or without left ventricular systolic dysfunction after acute myocardial infarction

Aims

This observational study aimed to investigate the association between beta-blocker therapy and clinical outcomes in patients with acute myocardial infarction (AMI), especially with mid-range or preserved left ventricular systolic function.

Methods and results

Among 13 624 patients enrolled in the Korea Acute Myocardial Infarction Registry-National Institute of Health (KAMIR-NIH), 12 200 in-hospital survivors were selected. Patients with beta-blockers showed significantly lower 1-year major adverse cardiac events (MACE), which was a composite of cardiac death, MI, revascularization, and readmission due to heart failure [9.7 vs. 14.3/100 patient-year; hazard ratio (HR) 0.84, 95% confidence interval (CI) 0.72–0.97; P = 0.022). However, this association had a significant interaction with left ventricular ejection fraction (LVEF). Beta-blocker therapy at discharge was associated with lower 1-year MACE in patients with LVEF ≤40% (HR 0.63, 95% CI 0.48–0.81; P &lt; 0.001), and 40% &lt;LVEF &lt; 50% (HR 0.69, 95% CI 0.51–0.94; P = 0.020), but not in patients with LVEF ≥50% (HR 1.16, 95% CI 0.91–1.48; P = 0.234).

Conclusions

Beta-blocker therapy at discharge was associated with better 1-year clinical outcomes in patients with reduced or mid-range LVEF after AMI, but not in patients with preserved LVEF. These data suggested that the long-term beta-blocker therapy may be guided by LVEF.

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.

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.