Role of β-blocker therapy in pediatric heart failure

Beta-Blockers and Their Current Role in Maternal and Neonatal Health: A Narrative Review of the Literature

Beta-blockers are a class of medications that act on beta-adrenergic receptors and are categorized as cardio-selective and non-selective. They are principally used to treat cardiovascular conditions such as hypertension and arrhythmias. Beta-blockers have also been used to treat non-cardiogenic indications in non-pregnant individuals and the pediatric population. In pregnancy, labetalol is the mainstay treatment for hypertension and other cardiovascular indications. However, contraindications to certain sub-types of beta-blockers include bradycardia, heart failure, obstructive lung diseases, and hemodynamic instability. There is conflicting evidence of the adverse effects on fetal and neonatal health due to a scarce safety and efficacy profile, and further studies are necessary to understand the pharmacokinetics of the different classes of beta-blockers in pregnancy and fetal health. Understanding the hemodynamic changes during the stages of pregnancy is important to target a more beneficial therapy for both mother and fetus as well as better neonatal outcomes. Beta-blocker use in the pediatric population is less documented in studies but does have the potential to treat various cardiogenic and non-cardiogenic conditions. Future comprehensive studies would further benefit the direction of beta-blocker treatment during pregnancy in neonates and pediatrics.

Patient-friendly extemporaneous formulation of bisoprolol: application to stability and bioavailability studies

Community and hospital pharmacists always face the challenge to prepare oral liquid extemporaneous formulations to fit the needs of a specific patient population when commercial forms or the required strength is unavailable. This study was performed to prepare a stable patient-friendly oral liquid extemporaneous formulation of bisoprolol. Eight different extemporaneous formulations were prepared using various suspending agent(s). The in vitro dissolution of all extemporaneous formulations was examined. A comprehensive accelerated stability study was carried out to evaluate the adequate beyond-use date of the most optimized extemporaneous formulation. A validated ultra-performance liquid chromatography method was used for the analysis and quantification of bisoprolol in the accelerated stability and bioavailability studies. A group of eight healthy volunteers was enrolled in a two-way cross-over experimental design to study the bioavailability of the most optimized extemporaneous formulation. The pharmacokinetic parameters of bisoprolol were estimated. Extemporaneous suspension containing 0.5% w/v xanthan gum was easily prepared with a simple, natural, safe, sugar-free excipients. It achieved the best dissolution behavior among other extemporaneous suspensions. It was an easily pourable viscous suspension with no sedimentation. At least 98% of the initial concentration of bisoprolol remained throughout the 6-month study period in the selected suspension regardless of the storage conditions. There was no perceptible change in color, odor, or taste, and no noticeable microbial growth was observed in any sample. The selected formulation was bioequivalent to the commercial tablet in terms of the rate and extent of absorption. This research may be of great help during development of appropriate extemporaneous formulation of bisoprolol fumarate. The simple preparation method could be utilized to draw up a standard operating procedure (SOP) easy to use by different types of pharmacy settings.

Serum and glucocorticoid inducible kinase 1 modulates mitochondrial dysfunction and oxidative stress in doxorubicin-induced cardiomyocytes by regulating Hippo pathway via Neural precursor cell-expressed developmentally down-regulated 4 type 2

Doxorubicin (Dox) was reported to cause mitochondrial dysfunction and oxidative stress in cardiomyocytes, leading to cardiomyocyte apoptosis and ultimately heart failure. Serum and glucocorticoid inducible kinase 1 (SGK1) participates in the progression of various cardiovascular diseases. Thus, we aimed to explore the role and regulatory mechanism of SGK1 in Dox-induced cardiomyocyte injury. The expression of SGK1 was evaluated in blood samples of heart failure children, and in myocardial tissues and blood samples of Dox-induced rats. Subsequently, we treated cardiomyocytes with Dox in vitro. A gain-of-function assay was performed to assess the effects of SGK1 on mitochondrial dysfunction and oxidative stress in Dox-induced cardiomyocytes. Furthermore, the modulation of SGK1 on Neural precursor cell-expressed developmentally down-regulated 4 type 2 (NEDD4-2) expression and the subsequent Hippo pathway was validated. In our study, we found that SGK1 was downregulated in blood samples of heart failure children, as well as myocardial tissues and blood samples of Dox-induced rats. SGK1 overexpression alleviated the decreases of mitochondrial complex activity, mitochondrial membrane potential, adenosine triphosphate (ATP) content and ATP synthetase activity stimulated by Dox. Besides, SGK1 overexpression reversed the promoting effects of Dox on oxidative stress and apoptosis. Mechanistically, SGK1 overexpression inhibited the expression of NEDD4-2 and blocked the subsequent activation of Hippo pathway. NEDD4-2 overexpression or activation of Hippo reversed the protective effects of SGK1 overexpression on Dox-induced cardiomyocyte injury. In conclusion, our results revealed that SGK1 modulated mitochondrial dysfunction and oxidative stress in Dox-induced cardiomyocytes by regulating Hippo pathway via NEDD4-2.

New Strategies in The Treatment of Advanced Heart Failure in Children and the current consensus of Cairo University Children Hospital heart failure working group

The long-term treatment of congestive heart failure (CHF) in children includes digoxin, diuretics and afterload reduction with angiotensin-converting enzyme (ACE) inhibitors. In spite of the wide use of these drugs being the standard, yet, pediatric heart failure (PHF) continued to be an important cause of morbidity and mortality in childhood. Introduction of new drugs has elevated the level of tolerance of these patients and played a role in delaying their urgent need to have heart transplant or Mechanical circulatory support (MCS). Together with a patient by patient tailored combination of different diuretics. We aim to present and discuss these new drugs and the combinations of regular drugs to reach the best outcome, as well as the consensus of our pediatric heart failure working group in Egypt.

Inhibition of β1-AR/Gαs signaling promotes cardiomyocyte proliferation in juvenile mice through activation of RhoA-YAP axis

The regeneration potential of the mammalian heart is incredibly limited, as cardiomyocyte proliferation ceases shortly after birth. β-adrenergic receptor (β-AR) blockade has been shown to improve heart functions in response to injury; however, the underlying mechanisms remain poorly understood. Here, we inhibited β-AR signaling in the heart using metoprolol, a cardio-selective β blocker for β1-adrenergic receptor (β1-AR) to examine its role in heart maturation and regeneration in postnatal mice. We found that metoprolol enhanced cardiomyocyte proliferation and promoted cardiac regeneration post myocardial infarction, resulting in reduced scar formation and improved cardiac function. Moreover, the increased cardiomyocyte proliferation was also induced by the genetic deletion of Gnas, the gene encoding G protein alpha subunit (Gαs), a downstream effector of β-AR. Genome wide transcriptome analysis revealed that the Hippo-effector YAP, which is associated with immature cardiomyocyte proliferation, was upregulated in the cardiomyocytes of β-blocker treated and Gnas cKO hearts. Moreover, the increased YAP activity is modulated by RhoA signaling. Our pharmacological and genetic studies reveal that β1-AR-Gαs-YAP signaling axis is involved in regulating postnatal cardiomyocyte proliferation. These results suggest that inhibiting β-AR-Gαs signaling promotes the regenerative capacity and extends the cardiac regenerative window in juvenile mice by activating YAP-mediated transcriptional programs.

Efficacy and safety of propranolol in infants with heart failure due to moderate-to-large ventricular septal defect (VSD-PHF study) - A prospective randomized trial

AIMS

The utility of beta-blocker therapy in infants with heart failure (HF) due to significant left-to-right shunt lesions is not known. The study aimed to assess the efficacy and safety of propranolol in infants with HF due to moderate-to-large ventricular septal defect (VSD).

METHODS

The prospective randomized trial included 80 infants with HF and moderate-to-large VSD, randomly allocated to receive either conventional therapy alone (n = 40) or propranolol plus conventional therapy (n = 40). The primary endpoint was a composite of all-cause mortality, hospitalization for HF and/or chest infection, and referral for surgery. The secondary clinical outcomes were the individual components of the composite endpoint. In addition, the patients were followed up to detect safety outcomes, for example, bronchospasm, bradyarrhythmia, and worsening HF symptoms.

RESULTS

The addition of propranolol therapy to the conventional medications did not result in significant improvement in the primary composite endpoint (32.50% vs. 52.50%; P = 0.07). There was a trend toward improvement, but the study is underpowered for this important question. However, propranolol therapy significantly decreased the risk of hospitalization (12.50% vs. 32.50%; P = 0.03) and worsening of Ross HF class (5.41% vs. 28.21%; P = 0.01) as compared to conventional therapy (estimated number needed to treat = 5). Propranolol did not result in any significant safety concerns in these infants except bronchospasm in an infant.

CONCLUSIONS

Propranolol therapy in infants with significant left-to-right shunt may prevent worsening in HF symptoms and hospitalization and is well tolerated. However, it does not reduce mortality or need for surgery.

Fundamental Investigations into Metoprolol Tartrate Deposition on Orodispersible Films by Inkjet Printing for Individualised Drug Dosing

Individualised medicine is continuously gaining attention in pharmaceutical research. New concepts and manufacturing technologies are required to realise this therapeutic approach. Off-label drugs used in paediatrics, such as metoprolol tartrate (MPT), are potential candidates for innovations in this context. Orodispersible films (ODFs) have been shown as an accepted alternative dosage form during the last years and inkjet printing is traded as seminal technology of precise deposition of active pharmaceutical ingredients (APIs). The objective of this study was to combine both technologies by developing imprinted ODFs based on hypromellose with therapeutically reasonable MPT single doses of 0.35 to 3.5 mg for paediatric use. After preselection, suitable ink compositions were analysed by confocal Raman microscopy regarding MPT distribution within the imprinted ODFs. Adjusted print settings, speed, print direction and angle, characterised the final ODF surface structure. The present investigations show that uniform dosages with acceptance values between 1 and 6 can be achieved. Nevertheless, changes in calibrated printed quantity due to nozzle aging have a significant effect on the final applied dose. At the lowest investigated quantity, the RSD was ±28% and at the highest, ±9%. This has to be considered for implementation of inkjet printing as a pharmaceutical production tool in the future.

Echocardiographic assessment of left ventricular dyssynchrony in Egyptian children with congestive heart failure due to dilated cardiomyopathy

OBJECTIVE

To evaluate the presence of cardiac dyssynchrony in Egyptian children with congestive heart failure due to dilated cardiomyopathy.

MATERIALS AND METHODS

A total of 30 children with congestive cardiac failure due to dilated cardiomyopathy and 30 healthy age-matched controls were examined with conventional echocardiography, tissue Doppler, and speckle tracking imaging.

RESULTS

Conventional Doppler echocardiography demonstrated significant left ventricular systolic and diastolic dysfunction in the patient group. Tissue Doppler showed significant decrease in S-wave velocity and E'/A' ratio, and prolonged isovolumic contraction and relaxation times of mitral annulus as well as significant prolongation in mean difference between time-to-peak systolic strain of the basal septal and basal lateral segments in the patient group compared with the control group (p<0.005). Speckle tracking imaging demonstrated significant prolongation in mean difference between time-to-peak systolic strain of anteroseptal and posterior segments in both circumferential and radial strain analysis in the patient group than in the control group (p<0.005). It also demonstrated significant prolongation in the mean difference between time-to-peak systolic strain of the basal septal and basal lateral segments in longitudinal strain analysis in the patient group than in the control group (p<0.005). A significant increase in the standard deviation of time-to-peak strain, as a marker of increased intra-ventricular dyssynchrony, was present in the patient group compared with the control group (p=0.008).

CONCLUSION

Children with congestive heart failure due to dilated cardiomyopathy usually suffer from significant intra-ventricular dyssynchrony. Tissue Doppler imaging and speckle tracking imaging strain analysis are helpful tools to detect the presence of cardiac dyssynchrony.