Magnesium supplementation reduces postoperative arrhythmias after cardiopulmonary bypass in pediatrics: a metaanalysis of randomized controlled trials

Dexmedetomidine and magnesium sulfate in preventing junctional ectopic tachycardia after pediatric cardiac surgery

BACKGROUND

Junctional ectopic tachycardia (JET) is a serious tachyarrhythmia following pediatric cardiac surgery. It isn't easy to treat and better to be prevented. This study aimed to examine the prophylactic effects of dexmedetomidine, MgSO4, or their combination in reducing JET following pediatric open cardiac surgery.

METHODS

Hundred and twenty children under 5 years, weighing more than 5 kg, who were scheduled for corrective acyanotic cardiac surgeries were randomized into three groups. Group MD (Dexmedetomidine-MgSO4 group): received dexmedetomidine 0.5 μg/kg IV over 20 min after induction, then infusion 0.5 μg/kg/h for 72 h, and 50 mg/kg bolus of MgSO4 with aortic cross-clamp release, then continued administration for 72 h postoperatively at a dose of 30 mg/kg/day. Group D (the dexmedetomidine group) received the same dexmedetomidine as the MD group in addition to normal saline instead of MgSO4. Group C (control group): received normal saline instead of dexmedetomidine and MgSO4. The primary outcome was the detection of JET incidence; the secondary outcomes were hemodynamic parameters, ionized Mg, vasoactive-inotropic score, extubation time, PCCU and hospital stay, and perioperative complications.

RESULTS

The incidence of JET was significantly reduced in Group MD and Group D (p = .007) compared to Group C. Ionized Mg was significantly higher in Group MD than in Groups D and C during rewarming and in the ICU (p < .001). Better hemodynamic profile in Group MD compared to Group D and Group C throughout surgery and in the ICU, the predictive indexes were significantly better in Group MD than in Groups D and C (p < .001). Including the extubation time, PCCU, and hospital stay.

CONCLUSION

Dexmedetomidine alone or combined with MgSO4 had a therapeutic role in the prevention of JET in children after congenital heart surgery.

The Link between Magnesium Supplements and Statin Medication in Dyslipidemic Patients

Many investigations have discovered a connection between statins and magnesium supplements. On one hand, increasing research suggests that chronic hypomagnesemia may be an important factor in the etiology of some metabolic illnesses, including obesity and overweight, insulin resistance and type 2 diabetes mellitus, hypertension, alterations in lipid metabolism, and low-grade inflammation. Chronic metabolic problems seem to be prevented by a high Mg intake combined with diet and/or supplements. On the other hand, it is known that statins lower the frequency of cardiac events, stroke, and mortality, not by lowering LDL-C, but by the capacity to reduce mevalonate formation. That will enhance endothelial function, inhibit vascular smooth muscle cell proliferation and migration and encourage macrophages to promote plaque stability and regression while reducing inflammation. Taking these factors into consideration, we did an extensive analysis of the relevant literature, comparing the effects of Mg² and statin medications on lipoproteins and, implicitly, on the key enzymes involved in cholesterol metabolism.

Early and Late Postoperative Tachyarrhythmias in Children and Young Adults Undergoing Congenital Heart Disease Surgery

The population of patients with congenital heart disease is constantly growing with an increasing number of individuals reaching adulthood. A significant proportion of these children and young adults will suffer from tachyarrhythmias due to the abnormal anatomy, the hemodynamic burden, or as a sequela of surgical treatment. Depending on the underlying mechanism, arrhythmias may arise in the early postoperative period (hours to days after surgery) or in the late postoperative period (usually years after surgery). A good understanding of the electrophysiological characteristics and pathophysiological mechanisms is therefore crucial to guide the therapeutic approach. Here, we synthesize the current state of knowledge on epidemiological features, risk factors, pathophysiological insights, electrophysiological features, and therapy regarding tachyarrhythmias in children and young adults undergoing reparative surgery for congenital heart disease. The evolution and latest data on treatment options, including pharmacological therapy, ablation procedures, device therapy decision, and thromboprophylaxis, are summarized. Finally, throughout this comprehensive review, knowledge gaps and areas for future research are also identified.

Causal Effect of Serum Magnesium on Osteoporosis and Cardiometabolic Diseases

Serum magnesium is associated with osteoporosis and cardiometabolic diseases, but their causal associations remain elusive. We used the two-sample Mendelian randomization (MR) study to explore the causal roles of serum magnesium on osteoporosis and cardiometabolic diseases by using the aggregated genome-wide association studies (GWASs). Six single-nucleotide polymorphisms (SNPs, p < 5 × 10^-8) associated with serum magnesium concentrations were all used as instrumental variables. A genetic predisposition to higher serum magnesium concentrations was inversely associated with lower lumbar spine bone mineral density (BMD, beta-estimate: -1.982, 95% CI: -3.328 to -0.635, SE: 0.687, p = 0.004), which was further confirmed by multiple sensitivity analyses. There was limited evidence of associations between serum magnesium and type 2 diabetes, coronary artery disease, heart failure, and atrial fibrillation. This work provided strong evidence that genetically increased serum magnesium concentrations were causally associated with low lumbar spine BMD and suggested that serum magnesium concentrations may be crucial to prevent osteoporosis.

A 15-Year-Old Male With Wide Complex Tachyarrhythmia

A 15-year-old male presented with exertional syncope and was found to be in an unstable regular wide complex tachyarrhythmia (WCT). After a trial of antiarrhythmic medication, his clinical condition declined, necessitating synchronized cardioversion. Although he noted symptomatic improvement after cardioversion, he was found to be in third-degree heart block. The patient was transported by rotor wing aircraft to a pediatric cardiac intensive care unit where he was ultimately diagnosed with Lyme disease. He was treated with a course of intravenous antibiotics, his heart block resolved, and he was discharged home with a good neurologic outcome.

Serum magnesium levels and risk of coronary artery disease: Mendelian randomisation study

BACKGROUND

Observational studies have shown that serum magnesium levels are inversely associated with risk of cardiovascular disease, but whether this association is causal is unknown. We conducted a Mendelian randomisation study to investigate whether serum magnesium levels may be causally associated with coronary artery disease (CAD).

METHODS

This Mendelian randomisation analysis is based on summary-level data from the CARDIoGRAMplusC4D consortium's 1000 Genomes-based genome-wide association meta-analysis of 48 studies with a total of 60,801 CAD cases and 123,504 non-cases. Six single-nucleotide polymorphisms associated with serum magnesium levels at genome-wide significance were used as instrumental variables.

RESULTS

A genetic predisposition to higher serum magnesium levels was inversely associated with CAD. In conventional Mendelian randomisation analysis, the odds ratio of CAD was 0.88 (95% confidence interval [CI] 0.78 to 0.99; P = 0.03) per 0.1-mmol/L (about 1 standard deviation) increase in genetically predicted serum magnesium levels. Results were consistent in sensitivity analyses using the weighted median and heterogeneity-penalised model averaging methods, with odds ratios of 0.84 (95% CI 0.72 to 0.98; P = 0.03) and 0.83 (95% CI 0.71 to 0.96; P = 0.02), respectively.

CONCLUSIONS

This study based on genetics provides evidence that serum magnesium levels are inversely associated with risk of CAD. Randomised controlled trials elucidating whether magnesium supplementation lowers the risk of CAD, preferably in a setting at higher risk of hypomagnesaemia, are warranted.

Magnesium sulfate in pediatric anesthesia: the Super Adjuvant

Magnesium is an essential chemical element in all organisms, intervening in most cellular enzymatic reactions; thus, its importance in homeostasis and as a therapeutic tool in highly challenging patients such as pediatrics. The primary purpose of this paper was to review the role of magnesium sulfate as an adjuvant drug in pediatric anesthesia. This compound already has the scientific backing in certain aspects such as analgesia or muscle relaxation, but only theoretical or empirical backing in others such as organ protection or inflammation, where it seems to be promising. The multitude of potential applications in pediatric anesthesia, its high safety, and low cost make magnesium sulfate could be considered a Super Adjuvant.

Neutralizing IL-6 reduces heart injury by decreasing nerve growth factor precursor in the heart and hypothalamus during rat cardiopulmonary bypass

AIMS

To investigate whether the expression of nerve growth factor precursor (proNGF) changes during cardiopulmonary bypass (CPB) and whether neutralizing interleukin-6 (IL-6) during CPB has cardiac benefits.

MAIN METHODS

Thirty patients undergoing CPB were recruited and their serum proNGF and troponin-I (TNI) were detected. In addition, rats were divided into three groups: CPB group, CPB with cardiac ischemia-reperfusion (IR) group, and a control group. The pre-CPB standard deviation of N-N intervals (SDNN) and post-CPB SDNN were compared. At the end of CPB, nerve peptide Y (NPY), acetylcholinesterase, cell apoptosis, and proNGF protein expression were measured in the heart and hypothalamus. Another rat cohort undergoing CPB was divided into two groups: an anti-IL-6 group with IL-6 antibody and a control group with phosphate buffer solution. At the end of CPB, serum hs-troponin-T and cardiac caspases 3 and 9 were detected. NPY and proNGF in the heart and hypothalamus were detected.

KEY FINDINGS

In patients, serum proNGF increased during CPB, and the concentration was positively correlated with TNI. In rats, cardiac autonomic nervous function was disturbed during CPB. More apoptotic cells and higher levels of proNGF were found in the heart and hypothalamus in the CPB groups than in the control groups. Neutralizing IL-6 was beneficial to lower cardiac injury by decreasing proNGF and apoptosis.

SIGNIFICANCE

CPB induced changes in proNGF in the heart and hypothalamus. Suppressing inflammation attenuated myocardial apoptosis and autonomic nerve function disturbance in CPB rats, likely due in part to regulation of proNGF in the heart and hypothalamus.

Magnesium Lowers the Incidence of Postoperative Junctional Ectopic Tachycardia in Congenital Heart Surgical Patients: Is There a Relationship to Surgical Procedure Complexity?

Magnesium sulfate was given to pediatric cardiac surgical patients during cardiopulmonary bypass period in an attempt to reduce the occurrence of postoperative junctional ectopic tachycardia (PO JET). We reviewed our data to evaluate the effect of magnesium on the occurrence of JET and assess a possible relationship between PO JET and procedure complexity. A total of 1088 congenital heart surgeries (CHS), performed from 2005 to 2010, were reviewed. A total of 750 cases did not receive magnesium, and 338 cases received magnesium (25 mg/kg). All procedures were classified according to Aristotle score from 1 to 4. Overall, there was a statistically significant decrease in PO JET occurrence between the two groups regardless of the Aristotle score, 15.3 % (115/750) in non-magnesium group versus 7.1 % (24/338) in magnesium group, P < 0.001. In the absence of magnesium, the risk of JET increased with increasing Aristotle score, P = 0.01. Following magnesium administration and controlling for body weight, surgical and aortic cross-clamp times in the analyses, reduction in adjusted risk of JET was significantly greater with increasing Aristotle level of complexity (JET in non-magnesium vs. magnesium group, Aristotle level 1: 9.8 vs. 14.3 %, level 4: 11.5 vs. 3.2 %; odds ratio 0.54, 95 % CI 0.31-0.94, P = 0.028). Our data confirmed that intra-operative usage of magnesium reduced the occurrence of PO JET in a larger number and more diverse group of CHS patients than has previously been reported. Further, our data suggest that magnesium's effect on PO JET occurrence seemed more effective in CHS with higher levels of Aristotle complexity.