Practical regimen for amiodarone use in preventing postoperative atrial fibrillation

Navigating the Incidence of Postoperative Arrhythmia and Hospitalization Length: The Role of Amiodarone and Other Antiarrhythmics in Prophylaxis

Antiarrhythmic drugs play a pivotal role in managing and preventing arrhythmias. Amiodarone, classified as a class III antiarrhythmic, has been used prophylactically to effectively prevent atrial fibrillation postoperatively in cardiac surgeries. However, there is a lack of consensus on the use of amiodarone and other antiarrhythmic drugs as prophylaxis to reduce the occurrence of all types of postoperative arrhythmias in cardiac and non-cardiac surgeries. A comprehensive PubMed query yielded 614 relevant papers, of which 52 clinical trials were analyzed. The data collection included the class of antiarrhythmics, timing or method of drug administration, surgery type, type of arrhythmia and its incidence, and hospitalization length. Statistical analyses focused on prophylactic antiarrhythmics and their respective reductions in postoperative arrhythmias and hospitalization length. Prophylactic amiodarone alone compared to placebo demonstrated a significant reduction in postoperative arrhythmia incidence in cardiac and non-cardiac surgeries (24.01%, p<0.0001), and it was the only treatment group to significantly reduce hospitalization length versus placebo (p = 0.0441). Prophylactic use of class 4 antiarrhythmics versus placebo also demonstrated a significant reduction in postoperative arrhythmia incidence (28.01%, p<0.0001), and while there was no significant statistical reduction compared to amiodarone (4%, p=0.9941), a lack of abundant data provides a case for further research on the prophylactic use of class 4 antiarrhythmics for this indication. Amiodarone prophylaxis remains a prime cornerstone of therapy in reducing postoperative arrhythmia incidence and hospitalization length. Emerging data suggests a need for a broader exploration of alternative antiarrhythmic agents and combination therapies, particularly class 4 antiarrhythmics, in both cardiac and non-cardiac surgeries. This meta-analysis depicts the effectiveness of amiodarone, among other antiarrhythmics, in postoperative arrhythmia incidence and hospitalization length reduction in cardiac and non-cardiac surgeries.

Prevention of postoperative atrial fibrillation in cardiac surgery: a quality improvement project

PURPOSE

Postoperative atrial fibrillation (POAF) has an incidence of 20-60% in cardiac surgery. The Society of Cardiovascular Anesthesiologists and the European Association of Cardiothoracic Anaesthesiology Practice Advisory have recommended postoperative beta blockers and amiodarone for the prevention of POAF. By employing quality improvement (QI) strategies, we sought to increase the use of these agents and to reduce the incidence of POAF among our patients undergoing cardiac surgery.

METHODS

This single-centre QI initiative followed the traditional Plan, Do, Study, Act (PDSA) cycle scientific methodology. A POAF risk score was developed to categorize all patients undergoing cardiac surgery as either normal or elevated risk. Risk stratification was incorporated into a preprinted prescribing guide, which recommended postoperative beta blockade for all patients and a postoperative amiodarone protocol for patients with elevated risk starting on postoperative day one (POD1). A longitudinal audit of all patients undergoing cardiac surgery was conducted over 11 months to track the use of prophylactic medications and the incidence of POAF.

RESULTS

Five hundred and sixty patients undergoing surgery were included in the QI initiative from 1 December 2020 to 1 November 2021. The baseline rate of POAF across all surgical subtypes was 39% (198/560). The use of prophylactic amiodarone in high-risk patients increased from 13% (1/8) at the start of the project to 41% (48/116) at the end of the audit period. The percentage of patients receiving a beta blocker on POD1 did fluctuate, but remained essentially unchanged throughout the audit (34.8% in December 2020 vs 46.7% in October 2021). After 11 months, the overall incidence of POAF was 29% (24.9% relative reduction). Notable reductions in the incidence of POAF were observed in more complex surgical subtypes by the end of the audit, including multiple valve replacement (89% vs 56%), aortic repair (50% vs 33%), and mitral valve surgery (45% vs 33%).

CONCLUSIONS

This single-centre QI intervention increased the use of prophylactic amiodarone by 28% for patients at elevated risk of POAF, with no change in the early postoperative initiation of beta blockers (46.7% of patients by POD1). There was a notable reduction in the incidence of POAF in patients at elevated risk undergoing surgery.

Atorvastatin and the influence on postoperative atrial fibrillation after surgical aortic valve replacement (STARC) in adults at Odense University Hospital, Denmark: study protocol for a randomised controlled trial

INTRODUCTION

Atrial fibrillation (AF) is the most common postoperative complication after surgical aortic valve replacement (SAVR) and occurs in up to 50% of the patients. Development of postoperative AF (POAF) is associated with a 2-3 fold increased risk of adverse events, including stroke, myocardial infarction and death.Several studies have implied that prophylactic Atorvastatin therapy could prevent POAF in patients undergoing coronary artery bypass graft. These studies suggest that Atorvastatin has rapid and significant pleiotropic actions that reduce the risk of POAF. However, prophylactic treatment with statins has yet to be understood in SAVR. The aim of this study is to investigate whether prophylactic administration of torvastatin reduces POAF in patients undergoing SAVR.

METHODS AND ANALYSIS

In this investigator-initiated, prospective, parallel-group, randomised, double-blind, placebo-controlled single-centre trial, 266 patients undergoing elective solitary SAVR with bioprosthetic valve, with no prior history of AF, and statin-naïve will be randomised (1:1) to treatment with Atorvastatin (80 mg once daily) or matching placebo for 1-2 weeks prior to and 30 days after surgery. The primary endpoint is POAF defined as an episode of irregular RR-intervals without a traceable p-wave of at least 30 s duration. After discharge and until day 30 after surgery, POAF will be documented by either rhythm strip or 12-lead ECG.

ETHICS AND DISSEMINATION

Protocol approval has been obtained from the Regional Scientific Ethical Committee for Southern Denmark (S-20210159), The Danish Medicines Agency (2021103821) and the Data Protection Agency (21/65621).The trial is conducted in accordance with the Declaration of Helsinki, the ICH-GCP (International Conference on Harmonisation Good Clinical Practice) guidelines and the legal regulations of Denmark. Study findings will be shared via peer-reviewed journal publication and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05076019.

Risk factors for new-onset atrial fibrillation during critical illness: A Delphi study

Background

New-onset atrial fibrillation (NOAF) is common during critical illness and is associated with poor outcomes. Many risk factors for NOAF during critical illness have been identified, overlapping with risk factors for atrial fibrillation in patients in community settings. To develop interventions to prevent NOAF during critical illness, modifiable risk factors must be identified. These have not been studied in detail and it is not clear which variables warrant further study.

Methods

We undertook an international three-round Delphi process using an expert panel to identify important predictors of NOAF risk during critical illness.

Results

Of 22 experts invited, 12 agreed to participate. Participants were located in Europe, North America and South America and shared 110 publications on the subject of atrial fibrillation. All 12 completed the three Delphi rounds. Potentially modifiable risk factors identified include 15 intervention-related variables.

Conclusions

We present the results of the first Delphi process to identify important predictors of NOAF risk during critical illness. These results support further research into modifiable risk factors including optimal plasma electrolyte concentrations, rates of change of these electrolytes, fluid balance, choice of vasoactive medications and the use of preventative medications in high-risk patients. We also hope our findings will aid the development of predictive models for NOAF.

Long-term survival after Carpentier-Edwards Perimount aortic valve replacement in Western Denmark: a multi-centre observational study

Background

This study describes the long-term survival, risk of reoperation and clinical outcomes of patients undergoing solitary surgical aortic valve replacement (SAVR) with a Carpentier-Edwards Perimount (CE-P) bioprosthetic in Western Denmark. The renewed interest in SAVR is based on the questioning regarding the long-term survival since new aortic replacement technique such as transcatheter aortic-valve replacement (TAVR) probably have shorter durability, why assessment of long-term survival could be a key issue for patients.

Methods

From November 1999 to November 2013 a cohort of a total of 1604 patients with a median age of 73 years (IQR: 69–78) undergoing solitary SAVR with CE-P in Western Denmark was obtained November 2018 from the Western Danish Heart Registry (WDHR). The primary endpoint was long-term survival from all-cause mortality. Secondary endpoints were survival free from major adverse cardiovascular and cerebral events (MACCE), risk of reoperation, cause of late death, patient-prothesis mismatch, risk of AMI, stroke, pacemaker or ICD implantation and postoperative atrial fibrillation (POAF). Time-to-event analysis was performed with Kaplan-Meier curve, cumulative incidence function was performed with Nelson-Aalen cumulative hazard estimates. Cox regression was applied to detect risk factors for death and reoperation.

Results

In-hospital mortality was 2.7% and 30-day mortality at 3.4%. The 5-, 10- and 15-year survival from all-cause mortality was 77, 52 and 24%, respectively. Survival without MACCE was 80% after 10 years. Significant risk factors of mortality were small valves, smoking and EuroSCORE II ≥4%. The risk of reoperation was < 5% after 7.5 years and significant risk factors were valve prosthesis-patient mismatch and EuroSCORE II ≥4%.

Conclusions

Patients undergoing aortic valve replacement with a Carpentier-Edwards Perimount valve shows a very satisfying long-term survival. Future research should aim to investigate biological valves long-term durability for comparison of different SAVR to different TAVR in long perspective.

New-onset postoperative atrial fibrillation after heart surgery

BACKGROUND

New-onset postoperative atrial fibrillation (poAF) complicates approximately 20-60% of all cardiac surgical procedures and is associated with an increased periprocedural mortality and morbitity, prolonged hospital stay, increased costs, and worse long-term survival. Unfortunately multiple advances in surgery and perioperative care over the last two decades have not led to a reduction in the incidence of poAF or associated complications in the daily clinical practice.

METHODS

A narrative review of the available literature was performed.

RESULTS

An extensive review of the pathophysiology of poAF following cardiac surgery, clinical, and procedural risk-factors is provided, as well as prophylactic measures and treatment.

CONCLUSION

Multiple strategies to prevent and manage poAF following heart surgery already exist. Our hope is that this review will facilitate more rigorous testing of prevention strategies, implementation of prophylaxis regimens as well as optimal treatment of this common and serious complication.

Atrial Fibrillation Post Coronary Artery Graft Surgery: A Review Of Literature

Atrial fibrillation (AF) is a failure that is observed in heart disease and is also known to be the most common heart rhythm disturbance post coronary artery bypass surgery. Although AF is considered a transient problem, it is usually accompanied with a variety of complications and morbidity for patients and may result in death. In the present study, pre- and post-operative considerable factors which may increase the risk and mortality of AF, and possible treatments have been concisely reviewed.

Comedication with interacting drugs predisposes amiodarone users in cardiac and surgical intensive care units to acute liver injury: A retrospective analysis

Risk factors and underlying mechanisms for liver injury associated with amiodarone remain elusive. This study aimed to investigate the drug-related covariates for acute liver injury by amiodarone-an intriguing compound of high lipophilicity, with a long half-life and notable efficacy.The medical, pharmacy, and laboratory records of new amiodarone users admitted to the cardiac or surgical intensive care units of a medical center were examined retrospectively. A Cox regression model with time-varying dose-related variables of amiodarone was utilized to estimate the hazard ratio (HR) of amiodarone-associated liver injury while adjusting for concomitant therapy and relevant covariates.Of the 131 eligible patients among 6,572 amiodarone users (46,402 prescriptions), 6 were identified as amiodarone-associated liver injury cases. In comparison to controls (n = 125), this liver injury cohort (n = 6) had significantly higher numbers of amiodarone-interacting (2.7 ± 2.0 vs 0.9 ± 0.9 drugs, P = .02) and hepatotoxic (3.8 ± 0.8 vs 2.5 ± 1.7 drugs, P = .03) comedications. The number of comedications with amiodarone-interacting potential (HR 2.07, 95% confidence interval [CI] 1.02-4.22, P = .04) and amiodarone cumulative doses standardized by body surface area (HR 6.82, 95% CI 1.72-27.04, P = .01) were independent risk factors for liver injury associated with amiodarone.Drug-related (amiodarone cumulative dose, interacting drugs) factors were significant predictors of amiodarone-associated acute liver injury. A prudent evaluation of each medication profile is warranted to attain precision medicine at the level of patient care, especially for those treated by medications with complex physicochemical and pharmacokinetic properties, such as amiodarone.

Amiodarone Protocol Provides Cost-Effective Reduction in Postoperative Atrial Fibrillation

BACKGROUND

Postoperative atrial fibrillation (POAF) after cardiac operations results in a significant increase in morbidity, mortality, and health care costs. Prophylactic amiodarone has been shown to reduce the incidence of POAF; however, the cost-effectiveness of a protocol-driven approach remains unknown.

METHODS

All patients with a Society of Thoracic Surgeons risk score enrolled in a prophylactic amiodarone protocol (n = 153) were propensity score matched 1:3 with patients before protocol implementation (n = 3,574). Multivariate logistic and linear regressions assessed the relative risks (POAF reduction and adverse medication effects) in the matched cohort of amiodarone therapy and costs, respectively. TreeAge cost-effectiveness software (TreeAge Software, Inc, Williamstown, MA) modeled the effects of prophylactic amiodarone costs, complication rates, and quality of life.

RESULTS

Of patients eligible for the prophylactic amiodarone protocol, 94.3% (281 of 298) were enrolled. Prophylactic amiodarone significantly reduced the rate of POAF (25.7% vs 16.8%, p < 0.0001). A total of 600 matched patients demonstrate no baseline differences in demographics, comorbidities, disease state, or operative factors, with a significant reduction in POAF without an increase in other associated complications. With the use these adjusted estimates, the prophylactic amiodarone protocol demonstrated a cost savings of $458 per patient. Sensitivity analysis confirmed the protocol is cost-effective for all protocol-related POAF risk reductions below an odds ratio of 0.726.

CONCLUSIONS

Implementation of a prophylactic amiodarone protocol significantly reduced risk-adjusted rates of POAF, with a cost savings of $458 per patient. This analysis demonstrates how rigorous quantitative analysis can evaluate the benefits of quality improvement projects.

Amiodaron in atrial fibrillation: post coronary artery bypass graft

BACKGROUND

Atrial fibrilation (AF) is the most common complication following heart surgeries; it often occurs in patients after coronary artery bypass graft (CABG). The purpose of this review is to categorize prophylaxes or treatment by administration of Amiodaron in patients with CABG.

DATA RESOURCES

We searched google scholar, pubmed, and Cochrane Library databases (the period 1970-2010) for articles on Amiodaron in CABG and cardiac surgery. A total of 1 561 articles were identified, and 30 articles met the criteria and were enrolled in this review.

RESULTS

Most studies supported Amiodarone for prophylaxi purpose in patients who were performed with CABG; few papers supported Amiodaron as a drug for treating CABG. The prophylaxis can decrease the incidence rate of AF in CABG, but if it uses as a treatment, the side effect of Amiodaron will decrease because all of the patients will not get Amiodarone. In the other hand use of Amiodarone as a treatment does not influence the length of hospital stay significantly but these kinds of study are so few.

CONCLUSION

No appropriate therapeutic method has been defined for AF. At present, the common way of treating AF following cardiac surgery is mainly based on prophylaxis in medical books and references.

Amiodarone Versus Propafenone to Treat Atrial Fibrillation after Coronary Artery Bypass Grafting: A Randomized Double Blind Controlled Trial

Background

Atrial fibrillation (AF) is one of the most common complications after cardiac surgery. Several therapeutic and preventive strategies have been introduced for postoperative AF, but the treatment and prophylaxis of AF remain controversial. We aimed to compare the efficacy of intravenous amiodarone and oral propafenone in the treatment of AF after coronary artery bypass grafting (CABG).

Methods

This was a randomized controlled trial performed in two hospitals in Shiraz, Iran from 2009 to 2012. We included all patients who underwent elective CABG and developed AF postoperatively. The patients were randomly assigned to receive propafenone or amiodarone. The duration of AF, the success rate of the treatment, the need for cardioversion, the frequency of repeated AF, and the need for repeating the treatment were compared.

Results

The duration of the first (p=0.361), second (p=0.832), and third (p=0.298) episodes of AF, the need for cardioversion (p=0.998), and the need to repeat the first and second doses of drugs (p=0.557, 0.699) were comparable between the study groups. Repeated AF was observed in 17 patients (30.9%) in the propafenone group and 23 patients (34.3%) in the amiodarone group (p=0.704).

Conclusion

Oral propafenone and intravenous amiodarone are equally effective in the treatment and conversion of recent-onset AF after CABG.

Interventions for preventing post-operative atrial fibrillation in patients undergoing heart surgery

BACKGROUND

Atrial fibrillation is a common post-operative complication of cardiac surgery and is associated with an increased risk of post-operative stroke, increased length of intensive care unit and hospital stays, healthcare costs and mortality. Numerous trials have evaluated various pharmacological and non-pharmacological prophylactic interventions for their efficacy in preventing post-operative atrial fibrillation. We conducted an update to a 2004 Cochrane systematic review and meta-analysis of the literature to gain a better understanding of the effectiveness of these interventions.

OBJECTIVES

The primary objective was to assess the effects of pharmacological and non-pharmacological interventions for preventing post-operative atrial fibrillation or supraventricular tachycardia after cardiac surgery. Secondary objectives were to determine the effects on post-operative stroke or cerebrovascular accident, mortality, cardiovascular mortality, length of hospital stay and cost of treatment during the hospital stay.

SEARCH METHODS

We searched the Cochrane Central Register of ControlLed Trials (CENTRAL) (Issue 8, 2011), MEDLINE (from 1946 to July 2011), EMBASE (from 1974 to July 2011) and CINAHL (from 1981 to July 2011).

SELECTION CRITERIA

We selected randomized controlled trials (RCTs) that included adult patients undergoing cardiac surgery who were allocated to pharmacological or non-pharmacological interventions for the prevention of post-operative atrial fibrillation or supraventricular tachycardia, except digoxin, potassium (K(+)), or steroids.

DATA COLLECTION AND ANALYSIS

Two review authors independently abstracted study data and assessed trial quality.

MAIN RESULTS

One hundred and eighteen studies with 138 treatment groups and 17,364 participants were included in this review. Fifty-seven of these studies were included in the original version of this review while 61 were added, including 27 on interventions that were not considered in the original version. Interventions included amiodarone, beta-blockers, sotalol, magnesium, atrial pacing and posterior pericardiotomy. Each of the studied interventions significantly reduced the rate of post-operative atrial fibrillation after cardiac surgery compared with a control. Beta-blockers (odds ratio (OR) 0.33; 95% confidence interval) CI 0.26 to 0.43; I(2) = 55%) and sotalol (OR 0.34; 95% CI 0.26 to 0.43; I(2) = 3%) appear to have similar efficacy while magnesium's efficacy (OR 0.55; 95% CI 0.41 to 0.73; I(2) = 51%) may be slightly less. Amiodarone (OR 0.43; 95% CI 0.34 to 0.54; I(2) = 63%), atrial pacing (OR 0.47; 95% CI 0.36 to 0.61; I(2) = 50%) and posterior pericardiotomy (OR 0.35; 95% CI 0.18 to 0.67; I(2) = 66%) were all found to be effective. Prophylactic intervention decreased the hospital length of stay by approximately two-thirds of a day and decreased the cost of hospital treatment by roughly $1250 US. Intervention was also found to reduce the odds of post-operative stroke, though this reduction did not reach statistical significance (OR 0.69; 95% CI 0.47 to 1.01; I(2) = 0%). No significant effect on all-cause or cardiovascular mortality was demonstrated.

AUTHORS' CONCLUSIONS

Prophylaxis to prevent atrial fibrillation after cardiac surgery with any of the studied pharmacological or non-pharmacological interventions may be favored because of its reduction in the rate of atrial fibrillation, decrease in the length of stay and cost of hospital treatment and a possible decrease in the rate of stroke. However, this review is limited by the quality of the available data and heterogeneity between the included studies. Selection of appropriate interventions may depend on the individual patient situation and should take into consideration adverse effects and the cost associated with each approach.

Evaluation of an evidence-based practice implementation: prophylactic amiodarone following coronary artery revascularization

Postoperative atrial fibrillation is the most frequent dysrhythmia following coronary artery bypass grafting and is associated with complications, additional therapy, and longer hospital stays. Prophylactic amiodarone protocols have been validated as safe and beneficial in the prevention of atrial fibrillation following cardiac surgery. This study evaluates the use of our current treatment protocol, given prophylactically, as feasible and effective in producing similar outcomes in postoperative atrial fibrillation reduction as well as identifies any perioperative risk factors associated with this arrhythmia.

Effect of Statins in Preventing Postoperative Atrial Fibrillation Following Cardiac Surgery

Background: Postoperative occurrence of AF has been associated with less favorable outcomes in patients undergoing cardiac surgery and may result in increased postoperative morbidity and mortality. Objectives: A focused clinical question was designed and a Meta-analysis of published studies was performed to identify the effect of preoperative use of statins on the occurrence of AF after cardiac surgery. Methods: Using the Medline database, the Cochrane clinical trials database and online clinical trial databases, we reviewed all RCTs and observational studies examining the effect of statins on AF occurrence following cardiac surgery. We searched for literature published before April 2009 and earlier. Results: This analysis identified 6 studies (observational studies) which examined the effect of preoperative use of statins on AF occurrence following cardiac surgery, involving 10165 patients. Contradictory to most of previous studies, the overall outcomes suggested that the statins group did not have a significant decrease in AF occurrence following cardiac surgery comparing to control group (P = 0.19). Conclusions: The preoperative medication of statins showed no significant decrease in AF occurrence following cardiac surgery in this Meta-analysis result. More prospective studies and researches are needed to explore and demonstrate the accurate mechanism and effect of statins on postoperative AF.

Amiodarone protects diabetics and non-diabetics undergoing coronary artery bypass grafting equally

OBJECTIVE

To evaluate amiodarone prophylaxis in diabetics and non-diabetics. Further to clarify whether the risk of developing atrial fibrillation is higher for diabetics than non-diabetic patients, and to evaluate whether the diabetic status has any influence on the length of in-hospital stay.

DESIGN

Subgroup analysis within a randomized, controlled, double-blinded trial.

RESULTS

At 30 days of follow-up atrial fibrillation was equally frequent among diabetics (22%) and non-diabetics (17%) (p =0.41). The length of in-hospital stay for diabetics was prolonged with 25% (9%; 45%). The prophylactic amiodarone was found equally efficient in diabetics and non-diabetics, as the relative risk ratios were 1.2 (0.4-5.4) and 2.0 (0.3-12.5), respectively.

CONCLUSIONS

Diabetics and non-diabetics had the same effect of the amiodarone prophylaxis regime. Atrial fibrillation developed equally among diabetics and non-diabetics, but the length of stay was prolonged for diabetics.