Nebivolol versus Carvedilol or Metoprolol in Patients Presenting with Acute Myocardial Infarction Complicated by Left Ventricular Dysfunction

The role of β-adrenergic receptors in the regulation of cardiac tolerance to ischemia/reperfusion. Why do β-adrenergic receptor agonists and antagonists protect the heart?

BACKGROUND

Catecholamines and β-adrenergic receptors (β-ARs) play an important role in the regulation of cardiac tolerance to the impact of ischemia and reperfusion. This systematic review analyzed the molecular mechanisms of the cardioprotective activity of β-AR ligands.

METHODS

We performed an electronic search of topical articles using PubMed databases from 1966 to 2023. We cited original in vitro and in vivo studies and review articles that documented the cardioprotective properties of β-AR agonists and antagonists.

RESULTS

The infarct-reducing effect of β-AR antagonists did not depend on a decrease in the heart rate. The target for β-blockers is not only cardiomyocytes but also neutrophils. β1-blockers (metoprolol, propranolol, timolol) and the selective β2-AR agonist arformoterol have an infarct-reducing effect in coronary artery occlusion (CAO) in animals. Antagonists of β1- and β2-АR (metoprolol, propranolol, nadolol, carvedilol, bisoprolol, esmolol) are able to prevent reperfusion cardiac injury. All β-AR ligands that reduced infarct size are the selective or nonselective β1-blockers. It was hypothesized that β1-AR blocking promotes an increase in cardiac tolerance to I/R. The activation of β1-AR, β2-AR, and β3-AR can increase cardiac tolerance to I/R. The cardioprotective effect of β-AR agonists is mediated via the activation of kinases and reactive oxygen species production.

CONCLUSIONS

It is unclear why β-blockers with the similar receptor selectivity have the infarct-sparing effect while other β-blockers with the same selectivity do not affect infarct size. What is the molecular mechanism of the infarct-reducing effect of β-blockers in reperfusion? Why did in early studies β-blockers decrease the mortality rate in patients with acute myocardial infarction (AMI) and without reperfusion and in more recent studies β-blockers had no effect on the mortality rate in patients with AMI and reperfusion? The creation of more effective β-AR ligands depends on the answers to these questions.

Nebivolol in oral subacute treatment prevents cardiac post-ischemic dysfunction in rats, but hyperthyroidism reduces this protection: mechanisms involved

Nebivolol could prevent dysfunction in patients suffering myocardial ischemia. However, influence of hyperthyroidism is not known. Consequences and mechanisms of nebivolol treatment were investigated in isolated hearts from euthyroid (EuT) and hyperthyroid (HpT) rats. Rats were orally treated during 1 week with 20 mg/kg/day nebivolol (O-Neb), 30 mg/kg/day atenolol (O-Ate), or not treated (C). Isolated perfused hearts were exposed to global ischemia and reperfusion (I/R) inside a flow calorimeter. Left diastolic ventricular pressure, developed contractile pressure (P), and total heat rate (Ht) were continuously measured, while infarct size was measured after 2-h R. EuT-C and HpT-C hearts developed similarly low post-ischemic contractile recovery and economy (P/Ht). Nebivolol totally prevented dysfunction and reduced infarction size in EuT hearts, but partially improved recovery in HpT rat hearts. Contrarily, oral atenolol totally prevented dysfunction in HpT hearts but partially in EuT hearts. Nebivolol effects were reversed by perfusing L-NAME in both conditions, but partially reduced by aminoguanidine in HpT. However, L-NAME increased P and P/Ht recoveries in EuT-C and HpT-C rat hearts, as well as melatonin. Oral nebivolol prevented post-ischemic dysfunction and infarction in EuT hearts due to adrenergic β1 blockade and activation of iNOS and/or eNOS, but the effect was attenuated in HpT hearts by excessive iNOS-dependent nitrosative pathways.

Synthesis and biological evaluation of [131I]iodocarvedilol as a potential radiopharmaceutical for heart imaging

The optimization of the radiolabeling yield of carvedilol with iodine-131 was described. Dependence of the labeling yield of [131I]iodocarvedilol on the concentration of carvedilol, chloramine-T content, pH of the reaction mixture and reaction time was studied in details. Carvedilol was labeled with iodine-131 at pH 6 with a labeling yield of 92.6 ± 2.77% by using 100 µg carvedilol, 200 µg chloramin-T (CAT) and 30 min reaction time. The formed [131I]iodocarvedilol was nearly stable for a time up to one day. Biodistribution of [131I]iodocarvedilol was investigated in experimental animals. [131/123I]iodocarvedilol was located in the heart with a concentration of 19.6 ± 0.41% of the injected dose at 60 min post injection. It has a high heart uptake and heart to liver ratio, both of which are beneficial for high-quality SPECT (single-photon emission computerized tomography) myocardial imaging. [131/123I]iodocarvedilol solve most the drawbacks of the FDA (Food and Drug Administration) approved 99mTc-sestamibi.

Metoprolol combined with nicorandil on unstable angina pectoris can reduce incidence of cardiovascular events and inflammatory reactions

OBJECTIVE

This research was designed to investigate the efficacy of metoprolol combined with nicorandil on unstable angina pectoris (UAP).

METHODS

Totally 174 UAP patients treated in the Laixi City People's Hospital from May 2017 to December 2019 were taken as the research objects. They were divided into the control (n=79, CG) and joint (n=95) groups (JG). Patients in the CG were treated with metoprolol, while those in the JG were treated with nicorandil. The clinical efficacy, adverse events and inflammatory reactions were observed.

RESULTS

The effective rate of the JG was better than that of the CG after treatment. There were no additional adverse reactions, and the incidence of cardiovascular events reduced. The changes of cardiac function manifested that the left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD) in the JG were lower than those in the CG, while the left ventricular ejection fraction (LVEF) was higher. In addition, the serum levels of total cholesterol (TC), triglyceride (TG), high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) in the JG were lower than those in the CG.

CONCLUSION

Metoprolol combined with nicorandil is effective for UAP patients, which reduces the incidence of cardiovascular adverse events and inhibits inflammatory reactions.

Therapeutic Properties of Highly Selective β-blockers With or Without Additional Vasodilator Properties: Focus on Bisoprolol and Nebivolol in Patients With Cardiovascular Disease

Bisoprolol and nebivolol are highly selective β₁-adrenoceptor antagonists, with clinical indications in many countries within the management of heart failure with reduced left ventricular ejection fraction (HFrEF), ischaemic heart disease (IHD), and hypertension. Nebivolol has additional vasodilator actions, related to enhanced release of NO in the vascular wall. In principle, this additional mechanism compared with bisoprolol might lead to more potent vasodilatation, which in turn might influence the effectiveness of nebivolol in the management of HFrEF, IHD and hypertension. In this article, we review the therapeutic properties of bisoprolol and nebivolol, as representatives of “second generation” and “third generation” β-blockers, respectively. Although head-to-head trials are largely lacking, there is no clear indication from published studies of an additional effect of nebivolol on clinical outcomes in patients with HFrEF or the magnitude of reductions of BP in patients with hypertension.

Comparison of carvedilol versus metoprolol in patients with acute myocardial infarction: A protocol for systematic review and meta-analysis

BACKGROUND

The existing meta-analyses and randomized studies on comparing the effects of carvedilol and metoprolol are of poor quality, with small sample sizes, and involve a homogeneous population. Therefore, to provide new evidence-based medical evidence for clinical treatment, we undertook a systematic review and meta-analysis to compare the mortality benefits of carvedilol with metoprolol head to head and determine the better beta-blocker in acute myocardial infarction (AMI) setting.

METHODS

Seven electronic databases including Web of Science, Embase, PubMed, Wanfang Data, Scopus, Science Direct, Cochrane Library will be searched in May 2021 by 2 independent reviewers. The protocol was written following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) statement guidelines. The primary outcome is all-cause mortality; secondary outcomes include complex cardiovascular events, sudden death, cardiovascular death, reinfarction, revascularization, readmission, ventricular arrhythmias, and drug withdrawal for all causes except death. All outcomes are pooled on random-effect model. A P value of <.05 is considered to be statistically significant.

RESULTS

The review will add to the existing literature by showing compelling evidence and improved guidance in clinic settings.

OSF REGISTRATION NUMBER

10.17605/OSF.IO/VSTJC.

Comparison of Metoprolol Versus Carvedilol After Acute Myocardial Infarction

Beta-blockers are typically prescribed following myocardial infarction (MI), but no specific beta-blocker is recommended. Of 7,057 patients enrolled in the OBTAIN multi-center registry of patients with acute MI, 4142 were discharged on metoprolol and 1487 on carvedilol. Beta-blocker dose was indexed to the target daily dose used in randomized clinical trials (metoprolol-200 mg; carvedilol-50 mg), reported as %. Beta-blocker dosage groups were >0% to12.5% (n = 1,428), >12.5% to 25% (n = 2113), >25% to 50% (n = 1,392), and >50% (n = 696). The Kaplan-Meier method was used to calculate 3-year survival. Correction for baseline differences was achieved by multivariable adjustment. Patients treated with carvedilol were older (64.4 vs 63.3 years) and had more comorbidities: hypertension, diabetes, prior MI, congestive heart failure, reduced left ventricular ejection fraction, and a longer length of stay. Mean doses for metoprolol and carvedilol did not significantly differ (37.2 ± 27.8% and 35.8 ± 31.0%, respectively). The 3-year survival estimates were 88.2% and 83.5% for metoprolol and carvedilol, respectively, with an unadjusted HR = 0.72 (p <0.0001), but after multivariable adjustment HR = 1.073 (p = 0.43). Patients in the >12.5% to 25% dose category had improved survival compared with other dose categories. Subgroup analysis of patients with left ventricular ejection fraction ≤40%, showed worse survival with metoprolol versus carvedilol (adjusted HR = 1.281; 95% CI: 1.024 to 1.602, p = 0.03). In patients with left ventricular ejection fraction >40%, there were no differences in survival with carvedilol versus metoprolol. In conclusion, overall survival after acute MI was similar for patients treated with metoprolol or carvedilol, but may be superior for carvedilol in patients with left ventricular ejection fraction ≤40%.

Biased agonism at β-adrenergic receptors

The β-adrenergic receptors (βARs) include three subtypes, β₁, β₂ and β₃. These receptors are widely expressed and regulate numerous physiological processes including cardiovascular and metabolic functions and airway tone. The βARs are also important targets in the treatment of many diseases including hypertension, heart failure and asthma. In some cases, the use of current βAR ligands to treat a disease is suboptimal and can lead to severe side effects. One strategy to potentially improve such treatments is the development of biased agonists that selectively regulate a subset of βAR signaling pathways and responses. Here we discuss the compounds identified to date that preferentially activate a G_s- or β-arrestin-mediated signaling pathway through βARs. Mechanistic insight on how these compounds bias signaling sheds light on the potential development of even more selective compounds that should have increased utility in treating disease.

A Soluplus/Poloxamer 407-based self-nanoemulsifying drug delivery system for the weakly basic drug carvedilol to improve its bioavailability

Carvedilol (CAR), a β-adrenoceptor and α1-receptor blocker, has pH-dependent solubility, which greatly limits its oral bioavailability. In this work, a precipitation inhibitor-based self-nanoemulsifying drug delivery system (PI-SNEDDS) was developed by employing Soluplus and Poloxamer 407 to improve drug dissolution and to inhibit drug precipitation in the gastrointestinal tract. In vitro phase distribution and in vivo dissolution studies indicated that PI-SNEDDS significantly increased drug content in the oil phase of the nanoemulsions in the stomach and greatly inhibited the subsequent precipitation of CAR in the intestine compared with the carvedilol self-nanoemulsifying drug delivery system (CAR SNEDDS) and the carvedilol tablets. Moreover, a 1.56-fold increase in the relative bioavailability of CAR was observed for the CAR PI-SNEDDS (397.41%) compared to a CAR SNEDDS (254.09%) with commercial capsules as a reference. Therefore, our developed PI-SNEDDS is a promising vehicle for improving the dissolution and bioavailability of poorly soluble drugs with pH-dependent solubility.

Role of Metoprolol Succinate in the Treatment of Heart Failure and Atrial Fibrillation: A Systematic Review

BACKGROUND

Beta-blockers are one of the most important classes of cardiovascular agents and have been considered a cornerstone therapy in heart diseases, such as heart failure (HF) and atrial fibrillation (AF). Among different beta-blockers, metoprolol is a selective beta1-adrenergic antagonist, which has been extensively used since the 1970s.

AREAS OF UNCERTAINTY

Although current guidelines include recommendations for the use of controlled-release metoprolol succinate in specific HF and AF indications, and despite extensive clinical experience with metoprolol, comparative evidence on the use of metoprolol succinate compared with other beta-blockers in these indications is limited.

DATA SOURCES

We systematically reviewed the data from head-to-head studies directly comparing this compound with other beta-blockers in the treatment of HF or AF. Only clinical trials and observational studies were considered; no other limits were applied. The quality and relevance of retrieved articles were reviewed.

RESULTS

A total of 18 articles of the 353 articles identified were selected for inclusion; 12 HF articles and 6 for AF. Additional references were identified from the bibliographies of retrieved articles. The studies show that oral prophylaxis with an appropriate dose of metoprolol may reduce new incidents of AF in high-risk patients. Furthermore, metoprolol succinate is associated with significant mortality and morbidity benefits in the treatment of HF.

CONCLUSIONS

Despite the introduction of newer beta-blockers with differing clinical characteristics since its introduction, metoprolol succinate remains a useful drug in both HF and AF.

A Critical Review of Nebivolol and its Fixed-Dose Combinations in the Treatment of Hypertension

β-Adrenergic receptor blockers (β-blockers) are well-known useful and cost-effective drugs for managing hypertensive patients with coronary heart disease, stroke, and heart failure. However, it is often difficult to use β-blockers for patients with asthma or chronic obstructive pulmonary disease (COPD). Moreover, most β-blockers negatively influence glucose or lipid metabolism. Nebivolol is a third-generation lipophilic β-1 receptor-selective blocker with nitric oxide-mediated vasodilatory effects, metabolically neutral and usually well tolerated by patients with asthma or COPD. Nebivolol has significant effects of reduction in central blood pressure and improvements in endothelial dysfunction and arterial stiffness. To summarize the merits and demerits of nebivolol in different clinical situations, we conducted a review using the word 'nebivolol' on Pubmed and Embase, limiting the search to hypertension, clinical trials, and meta-analyses. This review summarizes the clinical studies on nebivolol itself and on the combination of nebivolol with other antihypertensive drugs, such as hydrochlorothiazide, angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers, and amlodipine. Most studies showed the safety and well-tolerated profile of nebivolol and the combination of nebivolol with other antihypertensive drugs, which suggests that new fixed combinations of nebivolol with other antihypertensive drugs would be useful for patients who are unable to tolerate traditional β-blockers.

Assessing Prognosis of Acute Coronary Syndrome in Recent Clinical Trials: A Systematic Review

There is no recent comprehensive overview of contemporary clinical trials assessing short and long-term outcomes in patients with acute coronary syndrome (ACS). This paper reviews factors from recent clinical trials that influenced prognosis in patients with ACS. Cochrane and PubMed databases were screened systematically for clinical trials published in the English literature reporting on ACS prognosis. Two authors independently screened titles, abstracts, and full text. Studies meeting inclusion criteria evaluated the impact of modern practice on prognosis. In vitro and animal models studies, conference abstracts, imaging studies, and review articles were excluded. Disagreement in inclusion criteria was resolved by consensus. A large study of 8,859 patients showed no difference in all-cause mortality between 31 days and 2 years in patients with ST segment elevation myocardial infarction (STEMI) compared to those with non-ST segment elevation myocardial infarction (NSTEMI) or stable ischemic heart disease (SIHD). Other studies showed a significant increase in all-cause mortality in patients with STEMI within the first 30 days, with NSTEMI patients exhibiting a higher mortality rate compared to those with SIHD during the 2-year follow-up period. Our review found that women have a poorer short-term prognosis compared to men. Additionally, reports from patients receiving comprehensive and coordinated care showed longer survival rates. In view of the improved prognosis demonstrated for patients suffering from ACS, assessing prognosis in patients represents a formidable task in modern practice. Our review highlights the need for further evidence-based studies evaluating long-term outcomes on diagnostic and treatment strategies.

Nebivolol attenuates oxidative stress and inflammation in a guinea pig model of ovalbumin-induced asthma: a possible mechanism for its favorable respiratory effects

An experimental model of ovalbumin (OVA) induced asthma was used to assess the effects of nebivolol, the third-generation selective β₁-adrenergic receptor blocker, on airway reactivity, lung inflammation, and oxidative stress markers. The asthma induction protocol was done by OVA sensitization and challenge. Guinea pigs were classified into control, asthmatic, or asthmatic receiving nebivolol either 7.5 or 15 mg·kg^-1·day^-1 orally. At the end of the study respiratory, the anti-inflammatory and antioxidative effects of nebivolol were assessed. The asthmatic group exhibited a significant increase in early and late airway resistance, airway hyperreactivity to histamine, total and absolute leucocytic count, tumor necrosis factor-α, and interleukin-6 in bronchoalveolar lavage fluid and lung lipid peroxidation and a significant decrease in superoxide dismutase and glutathione compared to the control group. Additionally, there was a significant decrease in lung endothelial nitric oxide synthase (eNOS) and a significant increase in inducible nitric oxide synthase (iNOS) mRNA expression compared to the control group. The high dose of nebivolol counteracted the increased airway resistance induced by OVA, whereas it had no effect on airway hyperresponsiveness. Moreover, nebivolol exhibited significant anti-inflammatory and antioxidant effects and restored the altered levels of eNOS and iNOS compared to the asthmatic group. Collectively, these results suggest a beneficial effect of nebivolol in asthma.