Does prophylactic sotalol and magnesium decrease the incidence of atrial fibrillation following coronary artery bypass surgery: a propensity-matched analysis

Clinical practices for defining, detecting, and diagnosing postoperative atrial fibrillation after coronary revascularization surgery - A scoping review

OBJECTIVES

This scoping review was undertaken to understand the degree of variation in clinical practices associated with postoperative atrial fibrillation (POAF), following coronary revascularization surgery by collating and synthesising key concepts from current published literature.

REVIEW METHODS AND DATA SOURCES

This scoping review was conducted following the framework outlined by Askey and O'Malley. Reporting of this scoping review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. Initial searches were completed in September 2020 and updated in January 2023. Comprehensive searches to identify relevant published literature were carried out within CINAHL, MEDLINE, and ProQuest databases. All searches were limited to full-text papers published in English with human adult participants. Deductive content analysis using NVivo software was performed to synthesise the data.

RESULTS

A total of 692 studies were identified during the database searches. After the deletion of duplicates and the application of the inclusion and exclusion criteria, 73 studies were included in the scoping review. The included studies were published between 2001 and 2022 and included a total of 24,833 participants. Forty-six studies included a definition of POAF, with four of these citing a peak-body definition. A total of 24 included studies reported on electrocardiogram diagnostic criteria for POAF, with 13/24 [54%] describing these characteristics within their definition. The time-based diagnostic criteria ranged from a minimum duration of greater than 30 seconds to greater than 1 hour. The most frequently reported minimum-time thresholds were ≥30 seconds, reported in 12 of 51 (24%) studies and ≥5 min, reported in 13 of 51 (25%) studies.

CONCLUSIONS

There is a lack of consistency in clinical practice for defining, detecting, and diagnosing POAF, following coronary revascularization surgery. Consensus and standardisation of clinical practices are urgently needed.

Utility of magnesium sulfate in the treatment of rapid atrial fibrillation in the emergency department: a systematic review and meta-analysis

Atrial fibrillation with rapid ventricular response (Afib/RVR) is a frequent reason for emergency department (ED) visits and can be treated with a variety of pharmacological agents. Magnesium sulfate has been used to prevent and treat postoperative Afib/RVR. We performed a systematic review and meta-analysis to assess the effectiveness of magnesium for treatment of Afib/RVR in the ED. PubMed and Scopus databases were searched up to June 2021 to identify any relevant randomized trials or observational studies. We used Cochrane's Risk-of-Bias tools to assess study qualities and random-effects meta-analysis for the difference of heart rate (HR) before and after treatment. Our search identified 395 studies; after reviewing 11 full texts, we included five randomized trials in our analysis. There were 815 patients with Afib/RVR; 487 patients (60%) received magnesium treatment, whereas 328 (40%) patients received control treatment. Magnesium treatment was associated with significant reduction in HR [standardized mean difference (SMD), 0.34; 95% CI, 0.21-0.47; P < 0.001; I2 = 4%), but not associated with higher rates of sinus conversion (OR, 1.46; 95% CI, 0.726-2.94; P = 0.29), nor higher rates of hypotension and bradycardia (OR, 2.2; 95% CI, 0.62-8.09; P = 0.22). Meta-regressions demonstrated that higher maintenance dose (corr. coeff, 0.17; P = 0.01) was positively correlated with HR reductions, respectively. We observed that magnesium infusion can be an effective rate control treatment for patients who presented to the ED with Afib/RVR. Further studies with more standardized forms of control and magnesium dosages are necessary to assess the benefit/risk ratio of magnesium treatment, besides to confirm our observations.

Sotalol

Sotalol is effective for treating atrial fibrillation (AF), ventricular tachycardia, premature ventricular contractions, and supraventricular tachycardia. Racemic (DL) sotalol inhibits the rapid component of the delayed rectifier potassium current. There is a near linear relationship between sotalol dosage and QT interval prolongation. However, in dose ranging trials in patients with AF, low-dose sotalol was not more effective than placebo. Orally administered sotalol has a bioavailability of nearly 100%. The only significant drug interactions are the need to avoid or limit use of concomitant drugs that cause QT prolongation, bradycardia, and/or hypotension.

Levosimendan Use Decreases Atrial Fibrillation in Patients after Coronary Artery Bypass Grafting: A Pilot Study

Background: Atrial fibrillation (AF) often occurs after coronary artery bypass grafting (CABG) and can result in increased morbidity and mortality due to complications. In the present study, our goal was to investigate whether the use of levosimendan can reduce the frequency of AF after coronary artery bypass grafting in patients with poor left ventricle function. Material and Methods: To investigate the effectiveness of levosimendan in the prophylaxis of AF, we conducted a prospective, randomized, placebo-controlled clinical study on 200 consecutive patients in whom we performed elective CABG operations. Baseline characteristics were similar in both groups. A control group of 100 patients were treated with placebo (500 mL saline solution), whereas the levosimendan group (n = 100 patients) was treated with levosimendan. High-sensitivity C-reactive protein, cardiac troponin, and creatine kinase–MB levels were measured before surgery and 5 days postoperatively. Results: AF occurred in 12% of the levosimendan group and 36% of the control group. The occurrence of AF was significantly lower in the levosimendan group (P < 0.05). The duration of AF in the levosimendan group was significantly shorter than that in the control group (4.83 ± 1.12 and 6.50 ± 1.55 hours, respectively; P = 0.028). Our research showed that C-reactive protein was higher postoperatively in the control group than in the levosimendan group (P < 0.05). Conclusions: The incidence of postoperative AF in the levosimendan group was reduced significantly in patients with poor left ventricle function after CABG operations.

Magnesium adjunctive therapy in atrial arrhythmias

Magnesium (Mg) is an important intracellular ion with cardiac metabolism and electrophysiologic properties. A large percentage of patients with arrhythmias have an intracellular Mg deficiency, which is out of line with serum Mg concentrations, and this may explain the rationale for Mg's benefits as an atrial antiarrhythmic agent. A current limitation of antiarrhythmic therapy is that the potential for cardiac risk offsets some of the benefits of therapy. Mg enhances the balance of benefits to harms by enhancing atrial antiarrhythmic efficacy and reducing antiarrhythmic proarrhythmia potential as well as providing direct antiarrhythmic efficacy when used as monotherapy in patients undergoing cardiothoracic surgery.

Intravenous magnesium prevents atrial fibrillation after coronary artery bypass grafting: a meta-analysis of 7 double-blind, placebo-controlled, randomized clinical trials

Background

Postoperative atrial fibrillation (POAF) is the most common complication after coronary artery bypass grafting (CABG). The preventive effect of magnesium on POAF is not well known. This meta-analysis was undertaken to assess the efficacy of intravenous magnesium on the prevention of POAF after CABG.

Methods

Eligible studies were identified from electronic databases (Medline, Embase, and the Cochrane Library). The primary outcome measure was the incidence of POAF. The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity.

Results

Seven double-blind, placebo-controlled, randomized clinical trials met the inclusion criteria including 1,028 participants. The pooled results showed that intravenous magnesium reduced the incidence of POAF by 36% (RR 0.64; 95% confidence interval (CI) 0.50-0.83; P = 0.001; with no heterogeneity between trials (heterogeneity P = 0.8, I² = 0%)).

Conclusions

This meta-analysis indicates that intravenous magnesium significantly reduces the incidence of POAF after CABG. This finding encourages the use of intravenous magnesium as an alternative to prevent POAF after CABG. But more high quality randomized clinical trials are still need to confirm the safety.

Pharmacologic prophylaxis for atrial fibrillation following cardiac surgery: a systematic review

Atrial Fibrillation (AF) is the most common arrhythmia occurring after cardiac surgery. Its incidence varies depending on type of surgery. Postoperative AF may cause hemodynamic deterioration, predispose to stroke and increase mortality. Effective treatment for prophylaxis of postoperative AF is vital as reduces hospitalization and overall morbidity. Beta-blockers, have been proved to prevent effectively atrial fibrillation following cardiac surgery and should be routinely used if there are no contraindications. Sotalol may be more effective than standard b-blockers for the prevention of AF without causing an excess of side effects. Amiodarone is useful when beta-blocker therapy is not possible or as additional prophylaxis in high risk patients. Other agents such as magnesium, calcium channels blocker or non-antiarrhythmic drugs as glycose-insulin--potassium, non-steroidal anti-inflammatory drugs, corticosteroids, N-acetylcysteine and statins have been studied as alternative treatment for postoperative AF prophylaxis.

Does Sodium Nitroprusside Decrease the Incidence of Atrial Fibrillation After Myocardial Revascularization?

Background— Atrial fibrillation (AF) often occurs after coronary artery bypass grafting and can result in increased morbidity and mortality. In the present pilot study, our aim was to investigate whether sodium nitroprusside (SNP), as a nitric oxide donor, can reduce the frequency of post–coronary artery bypass grafting AF.

Methods and Results— To investigate the effectiveness of SNP in the prophylaxis of AF, we conducted a prospective, randomized, placebo-controlled clinical study on 100 consecutive patients in whom we performed elective and initial CABG operations. A control group of 50 patients were treated with placebo (dextrose 5% in water), whereas the SNP group (n=50 patients) was treated with SNP (0.5 μg · kg −1 · min −1 ) during the rewarming period. High-sensitivity C-reactive protein levels were measured before surgery and 5 days postoperatively. All patients were monitored postoperatively with telemetry. Baseline characteristics were similar in both treatment groups. AF occurred in 12% of the SNP group and 27% of the control group. The occurrence of AF was significantly lower in the SNP group ( P =0.005). The duration of AF in the SNP group was significantly shorter than that in the control group (5.33±1.86 and 7.55±1.94 hours, respectively; P =0.023). C-reactive protein levels were higher postoperatively in the control group than in the SNP group ( P <0.05). Postoperative AF significantly prolonged postoperative hospital stay ( P <0.05).

Conclusions— The incidence of postoperative AF in the SNP group was reduced significantly. Further studies are needed to better delineate the anti-AF profile of SNP.

Surgical feasibility of the injection of fibrin sealant in cardiac fat pads to reduce the incidence of postoperative atrial fibrillation after coronary artery bypass grafting or valve surgery: a pilot study

OBJECTIVE

: Atrial fibrillation (AF) is the most common complication following coronary artery bypass grafting or valve surgery.The autonomic nervous system is an important determinant in the development of AF. We have assessed the role of injection of fibrin sealant (FS) as a method to modify conduction in the fad pads, to mimic temporary denervation and to reduce the incidence of postoperative AF in patients undergoing coronary artery bypass grafting or valve surgery.

PATIENTS AND METHODS

: Twenty eligible patients who underwent coronary bypass grafting or aortic valve surgery in our Institution were included in this pilot - study.Detection of AF after surgical intervention was based on patient symptomatology and on daily electrocardiograms obtained on all patients. Telemetry was used in all patients for the entire hospitalization period.

RESULTS

: 20% of the studied population (n = 4) developed postoperative AF. At the time of discharge one patient (5%) had persistent AF.Postoperative mortality was 5% (n = 1) and not cardiac related. None of the patients required permanent pacemaker implantation.

CONCLUSIONS

: This first human study of FS injected into the anterior fad pads following low to moderate risk open heart surgery shows, that this procedure is safe and feasible. Moreover, CM -1 injection appears to reduce the need for postoperative intervention and/or treatment of AF by diminishing its incidence.