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

The Effect of Beta-Blocker Post-Myocardial Infarction With Ejection Fraction >40% Pooled Analysis From Seven Arabian Gulf Acute Coronary Syndrome Registries

The use of beta-blockers (BB) in reduced left ventricular ejection fraction (LVEF) post-myocardial infarction (MI) is associated with reduced 1-year mortality, while their role in patients with mid-range and preserved LVEF post-MI remains controversial. We studied 31,620 patients who presented with acute coronary syndrome (ACS) enrolled in seven Arabian Gulf registries between 2005 and 2017. Patients with LVEF ≤40% were excluded. The remaining cohort was divided into two groups: BB group (n = 15,541) and non-BB group (n = 2,798), based on discharge medications. Patients in the non-BB group were relatively younger (55.3 vs. 57.4, P = .004) but higher risk at presentation; with higher Global Registry of Acute Coronary Events (GRACE) score (119.2 vs 109.2, P < .001), higher percentage of cardiogenic shock (3.5 vs 1.4%, P < .001), despite lower prevalence of comorbidities, such as hypertension and hyperlipidemia. BB use was associated with lower 1-year mortality in a multivariate logistic regression analysis, adjusting for major confounders [adjusted odds ratio (OR): 0.71 (95% CI 0.51-0.99)]. This remained the case in a sensitivity analysis using propensity score matching [adjusted OR: 0.34 (95% CI 0.16-0.73)]. In this study, using Arabian Gulf countries registries, the use of BB after ACS with LVEF >40% was independently associated with lower 1-year mortality.

Beta-blocker therapy in patients with acute myocardial infarction: not all patients need it

Most of the evidences for beneficial effects of beta-blockers in patients with acute myocardial infarction (AMI) were from the clinical studies published in the pre-reperfusion era when anti-platelet drugs, statins or inhibitors of renin-angiotensin-aldosterone system which are known to reduce cardiovascular mortality of patients with AMI were not introduced. In the reperfusion era, beta-blockers' benefit has not been clearly shown except in patients with reduced ejection fraction (EF; ≤40%). In the era of the early reperfusion therapy for AMI, a number of patients with mildly reduced EF (>40%, <50%) or preserved EF (≥50%) become increasing. However, because no randomized clinical trials are available until now, the benefit and the optimal duration of oral treatment with beta-blockers in patients with mildly reduced or preserved EF are questionable. Registry data have not showed the association of oral beta-blocker therapy with decreased mortality in survivors without heart failure or left ventricular systolic dysfunction after AMI. In the Korea Acute Myocardial Infarction Registry-National Institute of Health of in-hospital survivors after AMI, the benefit of beta-blocker therapy at discharge was shown in patients with reduced or mildly reduced EF, but not in those with preserved EF, which provides new information about beta-blocker therapy in patients without reduced EF. However, clinical practice can be changed when the results of appropriate randomized clinical trials are available. Ongoing clinical trials may help to answer the unresolved issues of beta-blocker therapy in patients with AMI.

Long-term mortality after acute coronary syndromes among patients with normal, mildly reduced, or reduced ejection fraction

AIMS

Left ventricular ejection fraction (LVEF) ≤ 40% is a well-established risk factor for mortality after acute coronary syndromes (ACS). However, the long-term prognostic impact of mildly reduced ejection fraction (EF) (LVEF 41-49%) after ACS remains less clear.

METHODS AND RESULTS

This was a retrospective study enrolling patients admitted with ACS included in a single-centre databank. LVEF was assessed by echocardiography during index hospitalization. Patients were divided in the following categories according to LVEF: normal (LVEF ≥ 50%), mildly reduced (LVEF 41-49%), and reduced (LVEF ≤ 40%). The endpoint of interest was all-cause death after hospital discharge. A multivariable Cox model was used to adjust for confounders. A total of 3200 patients were included (1952 with normal EF, 375 with mildly reduced EF, and 873 with reduced EF). The estimated cumulative incidence rates of mortality at 10 years for patients with normal, mildly reduced, and reduced EF were 24.8%, 33.5%, and 41.3%, respectively. After adjustments, the presence of reduced EF was associated with higher mortality compared with normal EF [adjusted hazard ratio (HR) 1.64; 95% confidence interval (CI) 1.36-1.96; P < 0.001], as was mildly reduced EF compared with normal EF (adjusted HR 1.33; 95% CI 1.05-1.68; P = 0.019). The presence of reduced EF was not associated with a statistically significantly higher mortality compared with mildly reduced EF (adjusted HR 1.23; 95% CI 0.96-1.57; P = 0.095).

CONCLUSIONS

In patients with ACS, mildly reduced EF measured in the acute phase was associated with higher long-term mortality compared with patients with normal EF. These data emphasize the importance of anti-remodelling therapies for ACS patients who have LVEF in the mildly reduced range.

Analysis of Serum Interleukin-37 Level and Prognosis in Patients with ACS

Objective

To explore the level of serum interleukin-37 in patients with acute coronary syndrome (ACS) and its prognostic value.

Methods

Altogether, 121 continuous ACS cases from September 2017 to June 2020 were selected as the research group (RG), and 107 healthy individuals during the same period were obtained as the control group (CG). ELISA was applied to test IL-37 in the serum of the CG and the RG. Chemiluminescence immunoassay was applied to test NT-pro BNP and hs-cTnI in each group and immune scattering turbidimetry to test hs-CRP. The correlation of IL-37 with serum NT-pro BNP, hs-cTnI, and CRP was analyzed, and the value of IL-37 in diagnosis and prognosis prediction of patients with ACS was tested. Logistic regression was applied to test the independent risk factors affecting poor prognosis of patients with ACS.

Results

IL-37 was poorly expressed in patients with ACS, which had a high diagnostic value for ACS (sensitivity: 94.39%, specificity: 74.38%, and area under curve: 0.945). There was a negative correlation of IL-37 with serum NT-pro BNP, hs-cTnI, and CRP. IL-37 in patients with poor prognosis was markedly declined compared with that of patients with good prognosis, and the predicted AUC was 0.965. Logistic regression revealed that low IL-37, diabetes, high CRP, NT-pro BNP, and hs-cTnI in the blood were independent risk factors for poor prognosis in patients with ACS.

Conclusion

IL-37 is low expressed in patients with ACS, which has a good diagnostic and prognostic value for ACS, and may be applied as an important marker for the prediction of patients with ACS.

Similarities and Differences Between HFmrEF and HFpEF

The new guidelines classify heart failure (HF) into three subgroups based on the ejection fraction (EF): HF with reduced EF (HFrEF), HF with mid-range EF (HFmrEF), and HF with preserved EF (HFpEF). The new guidelines regarding the declaration of HFmrEF as a unique phenotype have achieved the goal of stimulating research on the basic characteristics, pathophysiology, and treatment of HF patients with a left ventricular EF of 40-49%. Patients with HFmrEF have more often been described as an intermediate population between HFrEF and HFpEF patients; however, with regard to etiology and clinical indicators, they are more similar to the HFrEF population. Concerning clinical prognosis, they are closer to HFpEF because both populations have a good prognosis and quality of life. Meanwhile, growing evidence indicates that HFmrEF and HFpEF show heterogeneity in presentation and pathophysiology, and the emergence of this heterogeneity often plays a crucial role in the prognosis and treatment of the disease. To date, the exact mechanisms and effective treatment strategies of HFmrEF and HFpEF are still poorly understood, but some of the current evidence, from observational studies and post-hoc analyses of randomized controlled trials, have shown that patients with HFmrEF may benefit more from HFrEF treatment strategies, such as beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists, and sacubitril/valsartan. This review summarizes available data from current clinical practice and mechanistic studies in terms of epidemiology, etiology, clinical indicators, mechanisms, and treatments to discuss the potential association between HFmrEF and HFpEF patients.

Heart Failure With Mid-range Ejection Fraction: A Distinctive Subtype or a Transitional Stage?

Heart failure with mid-range ejection fraction (HFmrEF) was first proposed by Lam and Solomon in 2014, and was listed as a new subtype of heart failure (HF) in 2016 European Society of Cardiology guidelines. Since then, HFmrEF has attracted an increasing amount of attention, and the number of related studies on this topic has grown rapidly. The diagnostic criteria on the basis of left ventricular ejection fraction (LVEF) are straightforward; however, LVEF is not a static parameter, and it changes dynamically during the course of HF. Thus, HFmrEF may not be an independent disease with a uniform pathophysiological process, but rather a collection of patients with different characteristics. HFmrEF is often associated with various cardiovascular and non-cardiovascular diseases. Thus, the pathophysiological mechanisms of HFmrEF are particularly complex, and its clinical phenotypes are diverse. The complexity and heterogeneity of HFmrEF may be one reason for inconsistent results between clinical studies. In fact, whether HFmrEF is a distinctive subtype or a transitional stage between HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF) is controversial. In this review, we discuss the clinical characteristics, treatment and prognosis of patients with HFmrEF, as well as the differences among HFmrEF, HFrEF, and HFpEF.

Treatment of Heart Failure with Mid-Range Ejection Fraction: What Is the Evidence

In this review, we briefly outline our current knowledge on the epidemiology, outcomes, and pathophysiology of heart failure (HF) with mid-range ejection fraction (HFmrEF), and discuss in more depth the evidence on current treatment options for this group of patients. In most studies, the clinical background of patients with HFmrEF is intermediate between that of patients with HF and reduced ejection fraction (HFrEF) and patients with HF and preserved ejection fraction (HFpEF) in terms of demographics and comorbid conditions. However, the current evidence, stemming from observational studies and post hoc analyses of randomized controlled trials, suggests that patients with HFmrEF benefit from medications that target the neurohormonal axes, a pathophysiological behavior that resembles that of HFrEF. Use of β-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists, and sacubitril/valsartan is reasonable in patients with HFmrEF, whereas evidence is currently scarce for other therapies. In clinical practice, patients with HFmrEF are treated more like HFrEF patients, potentially because of history of systolic dysfunction that has partially recovered. Assessment of left ventricular systolic function with contemporary noninvasive modalities, e.g., echocardiographic strain imaging, is promising for the selection of patients with HFmrEF who will benefit from neurohormonal antagonists and other HFrEF-targeted therapies.