Atrial Fibrillation

[Perioperative atrial fibrillation : Diagnosis with underestimated relevance]

Atrial fibrillation (AF) is the most common cardiac arrhythmia in adults, both in general and perioperatively and is associated with significant morbidity and mortality. The age of the patients is a major risk factor. The prevalence of AF in noncardiac surgery (NCS) varies widely from 0.4% to 30% and for cardiac surgery, especially major combined procedures, up to approximately 50%. Ectopic excitation centers and reentry mechanisms at the atrial level are favored as the main process of uncoordinated electrical atrial activity. The loss of atrial contraction can lead to a reduction in cardiac output of up to 20-25%. The increased risk of thromboembolism due to AF extends beyond the perioperative period. Medication-based prevention strategies have not yet gained widespread acceptance. Treatment strategies include frequency and rhythm control as well as the avoidance of thromboembolisms through anticoagulation.

Diagnosis and Treatment of New-Onset Perioperative Atrial Fibrillation

This article reviews medical and surgical risk factors for developing atrial fibrillation (AF), the most common sustained dysrhythmia in the United States. Evidence for assessment and management of patients with AF, including AF newly identified in the preoperative clinic, immediately preoperatively, intraoperatively, and unstable AF, is presented. A stepwise approach to guide anesthetic decision-making in the assessment of newly identified preoperative AF is proposed. Anesthetic considerations, including the potential impacts of anesthetic and vasopressor selection, and current evidence related to rate control and rhythm control via pharmacologic or electrical cardioversion as well as anticoagulation strategies are discussed.

A descriptive cross-sectional study of self-management in patients with nonvalvular atrial fibrillation

Self-management of non-valvular atrial fibrillation (NVAF) is characterized by complexity and diversity of content. Inadequate self-management exposes patients to the risk for complications such as stroke and bleeding. To assess the status and predictors of self-management in NVAF patients, a descriptive cross-sectional study was conducted. The self-management scales for atrial fibrillation were used to assess the status of self-management of patients who received Warfarin, NOAC, Aspirin, or No anticoagulant therapy. The general situation questionnaire was used to collect socio-demographic and clinical data from patients. A total of 555 participants completed the survey, with self-management score of 71.21 ± 12.33, 69.59 ± 13.37, 69.03 ± 12.20 and 66.12 ± 11.36 in Warfarin group, NOAC group, Aspirin group and No anticoagulant group, respectively. In Warfarin group lower educational status was associated with poor self-management; in Aspirin group, comorbidities and age < 65 years (P = .001) were associated with poor self-management; in No anticoagulant group, age < 65 years, single, poor sleep quality, and permanent AF were associated with poor self-management. Self-management was inadequate in patients with NVAF. Poor self-management might be related with the occurrence of cerebral embolism. For NVAF patients receiving anti-thrombotic therapy, relatively young age, comorbidities, and age can have a substantial impact on self-management performance; while age, type of AF, quality of sleep, married status are associated with self-management in patients with no anticoagulants.

Preoperative Atrial Fibrillation and Cardiovascular Outcomes After Noncardiac Surgery

BACKGROUND

The impact of pre-existing atrial fibrillation (AF) on outcomes after noncardiac surgery is not clear.

OBJECTIVES

We aimed to study the impact of AF on the risk of adverse outcomes after noncardiac surgery in a nationwide cohort.

METHODS

We identified Medicare beneficiaries admitted for noncardiac surgery from 2015 to 2019 and divided the study cohort into 2 groups: with and without AF. Noncardiac surgery was classified into vascular, thoracic, general, genitourinary, gynecological, orthopedics and neurosurgery, breast, head and neck, and transplant. We used propensity score matching on exact age, sex, race, urgency and type of surgery, revised cardiac risk index (RCRI) and CHA₂DS₂-VASc score, and tight caliper on other comorbidities. The study outcomes were 30-day mortality, stroke, myocardial infarction, and heart failure. We examined the incremental utility of AF in addition to RCRI to predict adverse events after noncardiac surgery.

RESULTS

The study cohort included 8,635,758 patients who underwent noncardiac surgery (16.4% with AF). Patients with AF were older, more likely to be men, and had higher prevalence of comorbidities. After propensity score matching, AF was associated with higher risk of mortality (OR: 1.31; 95% CI: 1.30-1.32), heart failure (OR: 1.31; 95% CI: 1.30-1.33), and stroke (OR: 1.40; 95% CI: 1.37-1.43) and lower risk of myocardial infarction (OR: 0.81; 95% CI: 0.79-0.82). Results were consistent in subgroup analysis by sex, race, type of surgery, and all strata of RCRI and CHA₂DS₂-VASc score. AF improved the discriminative ability of RCRI (C-statistic 0.73 to 0.76).

CONCLUSION

Pre-existing AF is independently associated with postoperative adverse outcomes after NCS.

A Genotype-Phenotype Analysis of Glutathione Peroxidase 4 in Human Atrial Myocardium and Its Association with Postoperative Atrial Fibrillation

Heterogeneity in the incidence of postoperative atrial fibrillation (POAF) following heart surgery implies that underlying genetic and/or physiological factors impart a higher risk of this complication to certain patients. Glutathione peroxidase-4 (GPx4) is a vital selenoenzyme responsible for neutralizing lipid peroxides, mediators of oxidative stress known to contribute to postoperative arrhythmogenesis. Here, we sought to determine whether GPX4 single nucleotide variants are associated with POAF, and whether any of these variants are linked with altered GPX4 enzyme content or activity in myocardial tissue. Sequencing analysis was performed across the GPX4 coding region within chromosome 19 from a cohort of patients (N = 189) undergoing elective coronary artery bypass graft (−/+ valve) surgery. GPx4 enzyme content and activity were also analyzed in matching samples of atrial myocardium from these patients. Incidence of POAF was 25% in this cohort. Five GPX4 variants were associated with POAF risk (permutated p ≤ 0.05), and eight variants associated with altered myocardial GPx4 content and activity (p < 0.05). One of these variants (rs713041) is a well-known modifier of cardiovascular disease risk. Collectively, these findings suggest GPX4 variants are potential risk modifiers and/or predictors of POAF. Moreover, they illustrate a genotype−phenotype link with this selenoenzyme, which will inform future mechanistic studies.

Early Thromboembolic Stroke Risk of Postoperative Atrial Fibrillation Following Cardiac Surgery

OBJECTIVE

The authors aimed to study the association between postoperative atrial fibrillation (POAF) and thromboembolic stroke and to determine risk factors for thromboembolic stroke after cardiac surgery.

DESIGN

The authors performed a secondary analysis from a randomized controlled trial (GRIP-COMPASS). The patients with thromboembolic stroke were compared with those without thromboembolic stroke, and the difference in the incidence of POAF between these groups was assessed. Odds ratios (OR) were calculated using logistic regression analyses. Brain imaging was studied for the occurrence of thromboembolic stroke during hospital admission, and POAF was monitored for seven days. To assess which characteristics were associated with occurrence of thromboembolic stroke, stepwise backward regression analysis was performed.

PARTICIPANTS

All adult consecutive cardiac surgery patients admitted postoperatively to the intensive care unit.

SETTING

Academic tertiary care medical center.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 910 patients included in this study, 26 patients (2.9%) had a thromboembolic stroke during hospital admission. The incidence of POAF during the first seven days after cardiac surgery in those with thromboembolic stroke was 65%, compared with 39% in those without thromboembolic stroke: adjusted OR 3.01 (95% confidence interval, 1.13-8.00). POAF, a history of peripheral vascular disease, a higher EuroSCORE, and a longer duration of surgery were associated with thromboembolic stroke.

CONCLUSIONS

POAF within seven days after cardiac surgery was associated with a three-fold increased risk for a thromboembolic stroke during hospital admission. Expeditious treatment of POAF may, therefore, reduce early stroke risk after cardiac surgery.

Perioperative Implications of the 2020 American Heart Association Scientific Statement on Drug-Induced Arrhythmias-A Focused Review

The recently released American Heart Association (AHA) scientific statement on drug-induced arrhythmias discussed medications commonly associated with bradycardia, supraventricular tachycardias, and ventricular arrhythmias. The foundational data for this statement were collected from general outpatient and inpatient populations. Patients undergoing surgical and minimally invasive treatments are a unique subgroup, because they may experience hemodynamic changes associated with anesthesia and their procedure, receive multiple drug combinations not given in either inpatient or outpatient settings, or experience postprocedural inflammatory syndromes. Accordingly, the generalizability of the AHA scientific statement to this perioperative population is unclear. This focused review highlights important aspects of the new AHA scientific statement and their application to the perioperative setting. The authors review medications frequently encountered and given by anesthesiologists and their risk of drug-induced arrhythmias and discuss common anesthetic and adjunctive medications and their associated risks of bradycardia, atrial fibrillation, torsades de pointes, and drug-induced Brugada syndrome. In many instances, the risk of arrhythmia reported by the AHA scientific statement in the general population appeared to be higher than found in perioperative arenas. Furthermore, the authors discuss the arrhythmia risk of additional medications commonly ordered or administered by anesthesiologists that are not included in the AHA scientific statement. As patient and procedural complexity increases and novel anesthetic combinations propagate, further research and observational studies will be required to delineate further perioperative risks for drug-induced arrhythmia.

Postoperative Atrial Fibrillation: Features, Mechanisms, and Clinical Management

Advances in atrial fibrillation (AF) management, perioperative medicine, and surgical techniques have reignited an interest in postoperative AF (POAF). POAF results from the interaction among subclinical atrial substrate, surgery-induced substrate, and transient postoperative factors. Prophylaxis for POAF after cardiac surgery is well established but the indications for preoperative treatment in noncardiac surgery need further investigation. A rate-control strategy is adequate for most asymptomatic patients with POAF and anticoagulation should be initiated for POAF more than 48 to 72 hours postsurgery. Research is needed to improve evidence-based management of POAF and guide long-term management in view of the substantial late recurrence-rate.

Perioperative pharmacotherapy to prevent cardiac complications in patients undergoing noncardiac surgery

Introduction: Despite advances in surgical and anesthetic techniques, perioperative cardiovascular complications are a major cause of 30-day perioperative mortality. Major cardiovascular complications after noncardiac surgery include myocardial ischemia, congestive heart failure, arrhythmias, and cardiac arrest. Along with surgical risk assessment, perioperative medical optimization can reduce the rates and clinical impact of these complications.Areas Covered: In this review, the authors discuss the pharmacological basis, existing evidence, and professional society recommendations for drug management in preventing cardiovascular complications in patients undergoing noncardiac surgery.Expert opinion: Perioperative management of cardiovascular disease is an increasingly important and growing area of clinical practice. Societal guidelines regarding the use of most routine cardiovascular medications are based on a number of large clinical studies and provide a basic foundation to guide management. However, the heterogeneous nature of patients, as well as surgeries, makes it practically impossible to devise a 'one size fits all' recommendation in this setting. Thus, the importance of a more individualized approach to perioperative risk stratification and management is being increasingly recognized. The underlying comorbidities and cardiac profile as well as the risk of cardiac complications associated with the planned surgery must be factored in to understand the nuance of the management strategies.