Heart Failure Guidelines on Pharmacotherapy

Riboflavin ameliorates pathological cardiac hypertrophy and fibrosis through the activation of short-chain acyl-CoA dehydrogenase

Short-chain acyl-CoA dehydrogenase (SCAD), the rate-limiting enzyme for fatty acid β-oxidation, has a negative regulatory effect on pathological cardiac hypertrophy and fibrosis. FAD, a coenzyme of SCAD, participates in the electron transfer of SCAD-catalyzed fatty acid β-oxidation, which plays a crucial role in maintaining the balance of myocardial energy metabolism. Insufficient riboflavin intake can lead to symptoms similar to short-chain acyl-CoA dehydrogenase (SCAD) deficiency or flavin adenine dinucleotide (FAD) gene abnormality, which can be alleviated by riboflavin supplementation. However, whether riboflavin can inhibit pathological cardiac hypertrophy and fibrosis remains unclear. Therefore, we observed the effect of riboflavin on pathological cardiac hypertrophy and fibrosis. In vitro experiments, riboflavin increased SCAD expression and the content of ATP, decreased the free fatty acids content and improved PE-induced cardiomyocytes hypertrophy and AngⅡ-induced cardiac fibroblasts proliferation by increasing the content of FAD, which were attenuated by knocking down the expression of SCAD using small interfering RNA. In vivo experiments, riboflavin significantly increased the expression of SCAD and the energy metabolism of the heart to improve TAC induced pathological myocardial hypertrophy and fibrosis in mice. The results demonstrate that riboflavin improves pathological cardiac hypertrophy and fibrosis by increasing the content of FAD to activate SCAD, which may be a new strategy for treating pathological cardiac hypertrophy and fibrosis.

Parkia speciosa Hassk. Empty Pod Extract Prevents Cardiomyocyte Hypertrophy by Inhibiting MAPK and Calcineurin-NFATC3 Signaling Pathways

Cardiac hypertrophy is an early hallmark during the clinical course of heart failure. Therapeutic strategies aiming to alleviate cardiac hypertrophy via the mitogen-activated protein kinase (MAPK)/calcineurin-nuclear factor of activated T-cells (NFAT) signaling pathway may help prevent cardiac dysfunction. Previously, empty pod ethanol crude extract of Parkia speciosa Hassk was shown to demonstrate protective effects against cardiomyocyte hypertrophy. Therefore, the current study aimed to investigate the effects of various fractions of the plant ethanol extract on the MAPK/NFAT signaling pathway in angiotensin II (Ang II)-induced cardiomyocyte hypertrophy. Simultaneous treatment with ethyl acetate (EA) fraction produced the most potent antihypertrophic effect evidenced by the reduced release of B-type natriuretic peptide (BNP). Subsequently, treatment with the EA fraction (6.25, 12.5, and 25 μg/mL) prevented an Ang II-induced increase in cell surface area, hypertrophic factors (atrial natriuretic peptide and BNP), reactive oxygen species, protein content, and NADPH oxidase 4 expression in the cells. Furthermore, EA treatment attenuated the activation of the MAPK pathway and calcineurin-related pathway (GATA-binding protein 4 and NFATC3), which was similar to the effects of valsartan (positive control). Our findings indicate that the EA fraction prevents Ang II-induced cardiac hypertrophy by regulating the MAPK/calcineurin-NFAT signaling pathway.

Pharmacology of Ivabradine and the Effect on Chronic Heart Failure

Chronic Heart Failure (CHF) is a complex clinical syndrome with a high incidence worldwide. Although various types of pharmacological and device therapies are available for CHF, the prognosis is not ideal, for which, the control of increased Heart Rate (HR) is critical. Recently, a bradycardic agent, ivabradine, is found to reduce HR by inhibiting the funny current (If). The underlying mechanism states that ivabradine can enter the Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels and bind to the intracellular side, subsequently inhibiting the If. This phenomenon can prolong the slow spontaneous phase in the diastolic depolarization, and thus, reduce HR. The clinical trials demonstrated the significant effects of the drug on reducing HR and improving the symptoms of CHF with fewer adverse effects. This review primarily introduces the chemical features and pharmacological characteristics of ivabradine and the mechanism of treating CHF. Also, some expected therapeutic effects on different diseases were also concluded. However, ivabradine, as a typical If channel inhibitor, necessitates additional research to verify its pharmacological functions.

Photobiomodulation therapy combined with carvedilol attenuates post-infarction heart failure by suppressing excessive inflammation and oxidative stress in rats

The post-myocardial infarction heart failure (HF) still carries a huge burden since current therapy is unsuccessful to abrogate poor prognosis. Thus, new approaches are needed, and photobiomodulation therapy (PBMt) may be a way. However, it is not known whether PBMt added to a standard HF therapy provides additional improvement in cardiac remodeling in infarcted rats. This study sought to determine the combined carvedilol-drug and PBMt with low-level laser therapy value in HF. Rats with large infarcts were treated for 30 days. The functional fitness was evaluated using a motorized treadmill. Echocardiography and hemodynamic measurements were used for functional evaluations of left ventricular (LV). ELISA, Western blot and biochemical assays were used to evaluate inflammation and oxidative stress in the myocardium. Carvedilol and PBMt had a similar action in normalizing pulmonary congestion and LV end-diastolic pressure, attenuating LV dilation, and improving LV systolic function. Moreover, the application of PBMt to carvedilol-treated rats inhibited myocardial hypertrophy and improved +dP/dt of LV. PBMt alone prevented inflammation with a superior effect than carvedilol. Carvedilol and PBMt normalized 4-hydroxynonenal (a lipoperoxidation marker) levels in the myocardium. However, importantly, the addition of PBMt to carvedilol attenuated oxidized protein content and triggered a high activity of the anti-oxidant catalase enzyme. In conclusion, these data show that the use of PBMt plus carvedilol therapy results in a significant additional improvement in HF in a rat model of myocardial infarction. These beneficial effects were observed to be due, at least in part, to decreased myocardial inflammation and oxidative stress.

Relationship between pulmonary hypertension and outcomes among patients with heart failure with reduced ejection fraction

Objectives: To identify predictors of pulmonary hypertension (PHT) and the predictive value of PHT for rehospitalization among patients with heart failure with reduced ejection fraction (HFrEF). Methods: A retrospective study of 351 hospitalized patients with heart failure (HF). Patients 18 years and above with HFrEF secondary to non-ischemic cardiomyopathy were reviewed. Patients with coronary artery disease, preserved ejection fraction and other secondary causes of PHT apart from HF were excluded. PHT as a predictor of 30-day and six-month re-admission was assessed as well as important possible predictors of PHT. Cox regression analysis, multiple linear regression as well as other statistical tools were employed as deemed appropriate. Results: Thirty-seven (37) and 99 patients were re-hospitalized within 30 days and 6 months after discharge for decompensated HF, respectively. After Cox regression analysis, higher hemoglobin reduced the odds of rehospitalization for decompensated HF (p = 0.015) within 30 days after discharge while higher pulmonary artery systolic pressure (PASP) (p = 0.002) and blood urea nitrogen (BUN) (p = 0.041) increased the odds of rehospitalization within 6 months of discharge. The predictors of the PHT among patients with HFrEF after multiple linear regression were low BMI (p = 0.027), increasing age (p = 0.006) and increased left atrial diameter (LAD) on echocardiography (p = 0.0001). Conclusion: Patients with HFrEF have a high predisposition to developing PHT if at admission, they have low BMI, dilated left atrium or are older. Patients with one or more of these attributes may need more intensive therapy to reduce the risk of developing PHT and in turn reduce readmission rates.

Therapeutic efficacy and safety of Shexiang Baoxin Pill combined with trimetazidine in elderly patients with heart failure secondary to ischaemic cardiomyopathy: A systematic review and meta-analysis

BACKGROUND

Shexiang Baoxin Pill (SBP) is one of the most commonly used traditional Chinese patent medicines for cardiovascular diseases. This systematic review was designed to provide rigorous therapeutic efficacy and safety evidence on the use of SBP combined with trimetazidine in elderly patients with heart failure (HF) secondary to ischaemic cardiomyopathy (ICM).

METHODS

Relevant randomized controlled trials (RCTs) investigating the clinical efficacy of SBP combined with trimetazidine in treating ICM-associated HF were widely searched in electronic databases, including PubMed, Cochrane library, EMBASE, CBM, CNKI, VMIS, and Wanfang up to January 1, 2018. The methodological quality of each trial was assessed according to the Cochrane Reviewers' Handbook 5.0. Meta-analysis was performed by using Review Manager 5.3.

RESULTS

Eighteen RCTs (N = 1532) that met the criteria were included in the review for the assessment of methodological quality. Meta-analysis showed that, when compared with conventional therapy, SBP combined with trimetazidine significantly improved the clinical efficacy and indices of cardiac function (including increasing left ventricular ejection fraction [LVEF] and 6-minute walk distance [6-MWD], decreasing left ventricular end-diastolic diameter [LVEDD] and left ventricular end-systolic diameter [LVESD]) without serious adverse reactions.

CONCLUSION

This work provides evidence of the benefit of SBP combined with trimetazidine for the treatment of HF secondary to ICM. More high quality and well-designed RCTs are needed to confirm these findings.

Exercise training normalizes elevated firing rate of hypothalamic presympathetic neurons in heart failure rats

Exercise training (ExT) normalizes elevated sympathetic nerve activity in heart failure (HF), but the underlying mechanisms are not well understood. In this study, we examined the effects of 3 wk of ExT on the electrical activity of the hypothalamic presympathetic neurons in the brain slice of HF rats. HF rats were prepared by ligating the left descending coronary artery. The electrophysiological properties of paraventricular nucleus neurons projecting to the rostral ventrolateral medulla (PVN-RVLM) were examined using the slice patch-clamp technique. The neuronal firing rate was elevated in HF rats, and ExT induced a reduction in the firing rate ( P < 0.01). This ExT-induced decrease in the firing rate was associated with an increased frequency of spontaneous and miniature inhibitory postsynaptic current (IPSCs; P < 0.05). There was no significant change in excitatory postsynaptic current. Replacing Ca²⁺ with Mg²⁺ in the recording solution reduced the elevated IPSC frequency in HF rats with ExT ( P < 0.01) but not in those without ExT, indicating an increase in the probability of GABA release. In contrast, ExT did not restore the reduced GABA_A receptor-mediated tonic inhibitory current in HF rats. A GABA_A receptor blocker (bicuculline, 20 μM) increased the firing rate in HF rats with ExT ( P < 0.01) but not in those without ExT. Collectively, these results show that ExT normalized the elevated firing activity by increasing synaptic GABA release in PVN-RVLM neurons in HF rats. Our findings provide a brain mechanism underlying the beneficial effects of ExT in HF, which may shed light on the pathophysiology of other diseases accompanied by sympathetic hyperactivation.