Ten-Year Trend of Oral Anticoagulation Use in Postoperative and Nonpostoperative Atrial Fibrillation in Routine Clinical Practice.

BACKGROUND: The study aimed to describe the patterns and trends of initiation, discontinuation, and adherence of oral anticoagulation (OAC) in patients with new-onset postoperative atrial fibrillation (POAF), and compare with patients newly diagnosed with non-POAF. METHODS AND RESULTS: This retrospective cohort study identified patients newly diagnosed with atrial fibrillation or flutter between 2012 and 2021 using administrative claims data from OptumLabs Data Warehouse. The POAF cohort included 118 366 patients newly diagnosed with atrial fibrillation or flutter within 30 days after surgery. The non-POAF cohort included the remaining 315 832 patients who were newly diagnosed with atrial fibrillation or flutter but not within 30 days after a surgery. OAC initiation increased from 28.9% to 44.0% from 2012 to 2021 in POAF, and 37.8% to 59.9% in non-POAF; 12-month medication adherence increased from 47.0% to 61.8% in POAF, and 59.7% to 70.4% in non-POAF. The median time to OAC discontinuation was 177 days for POAF, and 242 days for non-POAF. Patients who saw a cardiologist within 90 days of the first atrial fibrillation or flutter diagnosis, regardless of POAF or non-POAF, were more likely to initiate OAC (odds ratio, 2.92 [95% CI, 2.87-2.98]; P <0.0001), adhere to OAC (odds ratio, 1.08 [95% CI, 1.04-1.13]; P <0.0001), and less likely to discontinue (odds ratio, 0.83 [95% CI, 0.82-0.85]; P <0.0001) than patients who saw a surgeon or other specialties. CONCLUSIONS: The use of and adherence to OAC were higher in non-POAF patients than in POAF patients, but they increased over time in both groups. Patients managed by cardiologists were more likely to use and adhere to OAC, regardless of POAF or non-POAF.

Soluble ST2 is associated with postoperative atrial fibrillation after cardiac surgery in postmenopausal women.

BACKGROUND: Postoperative atrial fibrillation (POAF) represents the most common complication following cardiac surgery. Approximately one-third of patients experiencing POAF transition to atrial fibrillation within a year, challenging the notion of POAF as merely a transient event. Soluble ST2 (sST2) is an established biomarker regarding fibrosis and myocardial stretch, however, its role in predicting the onset of POAF remains unclear. METHODS: Preoperative sST2 levels have been assessed in 496 individuals with no prior history of AF who underwent elective cardiac surgery, including valve, coronary artery bypass graft surgery, or a combined procedure. RESULTS: The average age was 70 years, and 29.4 % were female. Overall, 42.3 % developed POAF. sST2 levels were found to be significantly higher in patients with POAF. Interestingly, sST2 was only predictive of POAF in females with an adjusted OR of 1.894 (95 %CI:1.103-3.253; p = 0.021) and not males (OR:1.091; 95 %CI:0.849-1.402; p = 0.495). Furthermore, within a linear regression model it was observed that for every 1 ng/mL increase in sST2 levels, the average POAF duration extended by 39.5 min (95 %CI:15.8-63.4 min; p = 0.001). CONCLUSION: sST2 predicts the onset of POAF in women but not men undergoing cardiac surgery. Furthermore, sST2 levels were associated with the subsequent burden of POAF. Thus, assessment of sST2 in addition to clinical risk factors could improve risk stratification for development of POAF following elective cardiac surgery.

Left atrial volume index and interleukin-6 as predictors for postoperative atrial fibrillation.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery. However, the predictive value of single indictor still remains controversial. This study aimed to assess the predictive value of combining preoperative left atrial volume index (LAVI) and postoperative interleukin-6 (IL-6) for POAF in the patients receiving cardiac surgery. METHODS: Patients who admitted to Nanjing First Hospital during the study period between December 2022 and June 2023, and underwent open-heart surgery without a history of atrial fibrillation (AF) were enrolled. The relationships between predictors and POAF were investigated using logistic regression analysis. We determined the combined predictive value of LAVI and IL-6 for POAF by measuring the changes in the area under the receiver operating characteristic curve (AUC) and calculating the net reclassification improvements (NRIs) and integrated discrimination improvement (IDIs). RESULTS: 102 patients were enrolled in this study, and 50 participants developed POAF (49.0%). Patients who experienced POAF had higher levels of preoperative LAVI and postoperative IL-6 than those who did not. Regression analysis revealed that larger LAVI and higher level of IL-6 were independently associated with increased risk of POAF. The combined addition of LAVI and IL-6 to the predictive model resulted in an evident increase in the AUC. Incorporating both LAVI and IL-6 increased IDIs in all models. CONCLUSION: Our results demonstrated that combined LAVI and IL-6 achieved a higher prediction performance for POAF.

Prophylactic Left Atrial Appendage Ligation During Coronary Artery Bypass Graft Surgery Allows Safe Avoidance of Anticoagulation Regardless of Postoperative Atrial Fibrillation.

Background New-onset postoperative atrial fibrillation (POAF) is the most common arrhythmia following cardiac surgery. POAF increases the risk of thromboembolism and stroke, as well as morbidity and mortality more generally. Despite evidence from the landmark PROTECT-AF and PREVAIL trials, left atrial appendage ligation (LAAL) is not routinely performed for thromboembolism prophylaxis in POAF, and anticoagulation remains the standard of care along with dual antiplatelet therapy. This study evaluated the efficacy of concomitant LAAL in eliminating the need for postoperative anticoagulation, regardless of POAF development, in patients undergoing coronary artery bypass grafting (CABG). Methods Between 2019 and 2021, 130 patients were selected to undergo concomitant LAAL while undergoing CABG surgery. Patients were then monitored for the incidence of new-onset POAF, and anticoagulation was strictly avoided for this indication. Demographic and outcome data were collected, with endpoints including transient ischemic attack (TIA) or stroke, death, and readmission within one year, as well as the length of hospital and intensive care unit (ICU) admissions. Results POAF occurred in 37 patients (28.5%), consistent with previous reports. However, none of the POAF patients experienced TIA or stroke during the one-year follow-up period, compared to 2 (2.15%) in the non-POAF group, a typical rate of postoperative stroke in such a patient population. No significant differences were observed between POAF and non-POAF cohorts in one-year stroke, all-cause mortality, readmission rates, or total hospital stay. Interestingly, the POAF cohort had a significantly longer mean ICU stay (4.24 vs 3.37 days, p = 0.0219), possibly due to the time required for arrhythmia control before discharge. The study population had a high mean CHA2DS2-VASc score (2.81), indicating an increased risk of thromboembolism, and a high mean HAS-BLED score, suggesting an elevated bleeding risk with anticoagulation. Conclusions LAAL appears to be an effective adjunct to CABG for thromboembolism prophylaxis in POAF. Formal anticoagulation was avoided in this study, with no significant differences in adverse events between POAF and non-POAF groups, suggesting that LAAL may be a suitable alternative to anticoagulation, especially in high-risk patients (e.g., those with elevated CHA2DS2-VASc or HAS-BLED scores). The safety and efficacy of this approach should be corroborated by larger randomized studies, such as the ongoing LeAAPS trial. LAAL during CABG may help reduce the risk of bleeding complications associated with anticoagulation while maintaining protection against thromboembolic events in patients who develop POAF.

New-onset postoperative atrial fibrillation after pulmonary endarterectomy is associated with adverse outcomes.

Background: New-onset postoperative atrial fibrillation (POAF) is a common complication after pulmonary thromboendarterectomy (PEA), yet the risk factors and their impact on prognosis remain poorly understood. This study aims to investigate the risk factors associated with new-onset POAF after PEA and elucidate its underlying connection with adverse postoperative outcomes. Methods: A retrospective analysis included 129 consecutive chronic thromboembolic pulmonary hypertension (CTEPH) patients and 16 sarcoma patients undergoing PEA. Univariate and multivariate analyses were conducted to examine the potential effects of preoperative and intraoperative variables on new-onset POAF following PEA. Propensity score matching (PSM) was then employed to adjust for confounding factors. Results: Binary logistic regression revealed that age (odds ratio [OR] = 1.041, 95% confidence interval [CI] = 1.008-1.075, p = 0.014) and left atrial diameter[LAD] (OR = 1.105, 95% CI = 1.025-1.191, p = 0.009) were independent risk factors for new-onset POAF after PEA. The receiver operating characteristic (ROC) curve indicated that the predictive abilities of age and LAD for new-onset POAF were 0.652 and 0.684, respectively. Patients with new-onset POAF, compared with those without, exhibited a higher incidence of adverse outcomes (in-hospital mortality, acute heart failure, acute kidney insufficiency, reperfusion pulmonary edema). Propensity score matching (PSM) analyses confirmed the results. Conclusion: Advanced age and LAD independently contribute to the risk of new-onset POAF after PEA. Patients with new-onset POAF are more prone to adverse outcomes. Therefore, heightened vigilance and careful monitoring of POAF after PEA are warranted.

Atrial fibrillation incidence after coronary artery bypass graft surgery and percutaneous coronary intervention: the prospective AFAF cohort study.

Objectives. Atrial fibrillation is a common arrhythmia in patients with ischemic heart disease. This study aimed to determine the cumulative incidence of new-onset atrial fibrillation after percutaneous coronary intervention or coronary artery bypass grafting surgery during 30 days of follow-up. Design. This was a prospective multi-center cohort study on atrial fibrillation incidence following percutaneous coronary intervention or coronary artery bypass grafting for stable angina or non-ST-elevation acute coronary syndrome. Heart rhythm was monitored for 30 days postoperatively by in-hospital telemetry and handheld thumb ECG recordings after discharge were performed. The primary endpoint was the cumulative incidence of atrial fibrillation 30 days after the index procedure. Results. In-hospital atrial fibrillation occurred in 60/123 (49%) coronary artery bypass graft and 0/123 percutaneous coronary intervention patients (p < .001). The cumulative incidence of atrial fibrillation after 30 days was 56% (69/123) of patients undergoing coronary artery bypass grafting and 2% (3/123) of patients undergoing percutaneous coronary intervention (p < .001). CABG was a strong predictor for atrial fibrillation compared to PCI (OR 80.2, 95% CI 18.1-354.9, p < .001). Thromboembolic stroke occurred in-hospital in one coronary artery bypass graft patient unrelated to atrial fibrillation, and at 30 days in two additional patients, one in each group. There was no mortality. Conclusion. New-onset atrial fibrillation during 30 days of follow-up was rare after percutaneous coronary intervention but common after coronary artery bypass grafting. A prolonged uninterrupted heart rhythm monitoring strategy identified additional patients in both groups with new-onset atrial fibrillation after discharge.

Enhanced Recovery After Surgery Cardiac Society turnkey order set for prevention and management of postoperative atrial fibrillation after cardiac surgery: Proceedings from the American Association for Thoracic Surgery ERAS Conclave 2023.

Background: Postoperative atrial fibrillation (POAF) is a prevalent complication following cardiac surgery that is associated with increased adverse events. Several guidelines and expert consensus documents have been published addressing the prevention and management of POAF. We aimed to develop an order set to facilitate widespread implementation and adoption of evidence-based practices for POAF following cardiac surgery. Methods: Subject matter experts were consulted to translate existing guidelines and literature into a sample turnkey order set (TKO) for POAF. Orders derived from consistent class I or IIA or equivalent recommendations across referenced guidelines and consensus manuscripts appear in the TKO in bold type. Selected orders that were inconsistently class I or IIA, class IIB, or supported by published evidence appear in italic type. Results: Preoperatively, the recommendation is to screen patients for paroxysmal or chronic atrial fibrillation and initiate appropriate treatment based on individual risk stratification for the development of POAF. This may include the administration of beta-blockers or amiodarone, tailored to the patient's specific risk profile. Intraoperatively, surgical interventions such as posterior pericardiotomy should be considered in selected patients. Postoperatively, it is crucial to focus on electrolyte normalization, implementation strategies for rate or rhythm control, and anticoagulation management. These comprehensive measures aim to optimize patient outcomes and reduce the occurrence of POAF following cardiac surgery. Conclusions: Despite the well-established benefits of implementing a multidisciplinary care pathway for POAF in cardiac surgery, its adoption and implementation remain inconsistent. We have developed a readily applicable order set that incorporates recommendations from existing guidelines.

Landiolol for Treatment of New-Onset Atrial Fibrillation in Critical Care: A Systematic Review.

Background: new-onset atrial fibrillation remains a common complication in critical care settings, often necessitating treatment when the correction of triggers is insufficient to restore hemodynamics. The treatment strategy includes electric cardioversion in cases of hemodynamic instability and either rhythm control or rate control in the absence of instability. Landiolol, an ultrashort beta-blocker, effectively controls heart rate with the potential to regulate rhythm. Objectives This review aims to compare the efficacy of landiolol in controlling heart rate and converting to sinus rhythm in the critical care setting. Methods: We conducted a comprehensive review of the published literature from 2000 to 2022 describing the use of landiolol to treat atrial fibrillation in critical care settings, excluding both cardiac surgery and medical cardiac care settings. The primary outcome assessed was sinus conversion following landiolol treatment. Results: Our analysis identified 17 publications detailing the use of landiolol for the treatment of 324 critical care patients. While the quality of the data was generally low, primarily comprising non-comparative studies, landiolol consistently demonstrated similar efficacy in controlling heart rate and facilitating conversion to sinus rhythm in both non-surgical (75.7%) and surgical (70.1%) settings. The incidence of hypotension associated with landiolol use was 13%. Conclusions: The use of landiolol in critical care patients with new-onset atrial fibrillation exhibited comparable efficacy and tolerance in both non-surgical and surgical settings. Despite these promising results, further validation through randomized controlled trials is necessary.

Atrial Arrhythmias Following Pulmonary Thromboendarterectomy: A Comprehensive Review Of Current Literature.

Chronic thromboembolic pulmonary hypertension (CTEPH) presents as a progressive vascular condition arising from previous episodes of acute pulmonary embolism, contributing to the development of pulmonary hypertension (PH). Pulmonary thromboendarterectomy (PTE) is the gold-standard surgical treatment for CTEPH; however, it may be associated with postoperative sequelae, including atrial arrhythmias (AAs). This comprehensive literature review explores the potential mechanisms for PTE-induced AAs with emphasis on the role of PH-related atrial remodelling and the predisposing factors. The identified preoperative predictors for AAs include advanced age, male gender, elevated resting heart rate, previous AAs, and baseline elevated right atrial pressure. Furthermore, we explore the available data on the association between post-PTE pericardial effusions and the development of AAs. Lastly, we briefly discuss the emerging role of radiomic analysis of epicardial adipose tissue as an imaging biomarker for predicting AAs.

Circulating BMP10 Levels Associate With Late Postoperative Atrial Fibrillation and Left Atrial Endomysial Fibrosis.

BACKGROUND: Serum bone morphogenetic protein 10 (BMP10) blood levels are a marker for history of atrial fibrillation (AF) and for major adverse cardiovascular events in patients with AF, including stroke, AF recurrences after catheter ablations, and mortality. The predictive value of BMP10 in patients undergoing cardiac surgery and association with morphologic properties of atrial tissues are unknown. OBJECTIVES: This study sought to study the correlation between BMP10 levels and preoperative clinical traits, occurrence of early and late postoperative atrial fibrillation (POAF), and atrial fibrosis in patients undergoing cardiac surgery. METHODS: Patients with and without preoperative AF history undergoing first cardiac surgery were included (RACE V, n = 147). Preoperative blood biomarkers were analyzed, left (n = 114) and right (n = 125) atrial appendage biopsy specimens were histologically investigated after WGA staining, and postoperative rhythm was monitored continuously with implantable loop recorders (n = 133, 2.5 years). RESULTS: Adjusted multinomial logistic regression indicated that BMP10 accurately reflected a history of persistent AF (OR: 1.24, 95% CI: 1.10-1.40, P = 0.001), similar to NT-pro-BNP. BMP10 levels were associated with increased late POAF90 occurrence after adjustment for age, sex, AF history, and early POAF occurrence (HR: 1.07 [per 0.1 ng/mL increase], 95% CI: 1.00-1.14, P = 0.041). Left atrial endomysial fibrosis (standardized ß = 0.22, P = 0.041) but not overall fibrosis (standardized Β = 0.12, P = 0.261) correlated with circulating BMP10 after adjustment for age, sex, AF history, reduced LVF, and valvular surgery indication. CONCLUSIONS: Increased BMP10 levels were associated with persistent AF history, increased late POAF incidence, and LAA endomysial fibrosis in a diverse sample of patients undergoing cardiac surgery.

The association between low serum calcium level and new-onset atrial fibrillation after coronary artery bypass grafting.

OBJECTIVES: This study aims to investigate the relationship between serum calcium (SC) levels and the incidence of postoperative atrial fibrillation (POAF) in patients undergoing coronary artery bypass graft surgery. METHODS: This retrospective, observational cohort study consecutively enrolled patients undergoing isolated coronary artery bypass grafting in Beijing Anzhen Hospital from January 2018 to December 2021. Patients with a previous history of atrial fibrillation or atrial flutter or requiring concomitant cardiac surgery were excluded. A logistic regression model was used to determine predictors of POAF. Multivariable adjustment, inverse probability of treatment weighting and propensity score matching were used to adjust for confounders. Moreover, we conducted univariable and multivariable logistic regression analyses on preoperative and postoperative SC and ionized SC levels. RESULTS: The analysis encompassed 12 293 patients. The POAF rate was significantly higher in patients with low SC level than those without (1379 [33.9%] vs 2375 [28.9%], P < 0.001). Low SC level was associated with an increased odds ratio of POAF (odds ratio [95% confidence interval]: 1.27 [1.18-1.37], P < 0.001). Inverse probability of treatment weighting and propensity score matching analyses confirmed the results. The increased POAF rate in low SC level group still existed among subgroup analysis based on different age, sex, body mass index, hypertension, hyperlipidaemia, CHA2DS2-VASc and magnesium. CONCLUSIONS: Low SC level indicates elevated POAF risk in patients undergoing isolated coronary artery bypass graft surgery even after the adjustment for age, sex, cardiovascular risk factors, echocardiographic parameters and laboratory markers.

Partial CArdiac Denervation to Prevent Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting (pCAD-POAF): Study Protocol for a Randomized Controlled Trial.

Postoperative atrial fibrillation (POAF) is commonly seen in patients who underwent coronary artery bypass grafting (CABG), increasing the risk of morbidity, mortality, and hospital expenses. This study aimed to evaluate the effect of partial cardiac denervation, which is achieved by cutting off the ligament of Marshall and resecting the fat pad along the Waterston groove, on the prevention of POAF after CABG. Patients planned for CABG at our center were screened for eligibility in this study. A total of 430 patients were randomized into the intervention (partial cardiac denervation) group and control group. Intraoperative high-frequency electrical stimulation and further histologic analysis were performed in a certain number of patients to confirm the existence of ganglia. All patients were continuously monitored for the incidence of POAF through an electrophysiologic device until the sixth day postoperatively, and required to complete a 30-day follow-up (12-lead electrocardiogram and echocardiogram assessment) after discharge. The primary end point is the incidence of POAF, whereas the secondary end points are the cost-effectiveness and safety outcomes. In conclusion, this trial will evaluate whether partial cardiac denervation through cutting off the ligament of Marshall and resecting the fat pad along the Waterston groove can reduce the incidence of POAF after CABG. If this procedure is revealed to be effective and safe, it may provide a potential therapeutic approach to prevent POAF in this group of patients.

Efficacy and Safety of Botulinum Toxin Type A for the Prevention of Postoperative Atrial Fibrillation.

BACKGROUND: Postoperative atrial fibrillation (POAF) is associated with increased morbidity and mortality. Epicardial injection of botulinum toxin may suppress POAF. OBJECTIVES: This study sought to assess the safety and efficacy of AGN-151607 for the prevention of POAF after cardiac surgery. METHODS: This phase 2, randomized, placebo-controlled trial assessed the safety and efficacy of AGN-151607, 125 U and 250 U vs placebo (1:1:1), for the prevention of POAF after cardiac surgery. Randomization was stratified by age (<65, ≥65 years) and type of surgery (nonvalvular/valve surgery). The primary endpoint was the occurrence of continuous AF ≥30 seconds. RESULTS: Among 312 modified intention-to-treat participants (placebo, n = 102; 125 U, n = 104; and 250 U, n = 106), the mean age was 66.9 ± 6.8 years; 17% were female; and 64% had coronary artery bypass graft (CABG) only, 12% had CABG + valve, and 24% had valve surgery. The primary endpoint occurred in 46.1% of the placebo group, 36.5% of the 125-U group (relative risk [RR] vs placebo: 0.80; 95% CI: 0.58-1.10; P = 0.16), and 47.2% of the 250-U group (RR vs placebo: 1.04; 95% CI: 0.79-1.37; P = 0.78). The primary endpoint was reduced in the 125-U group in those ≥65 years of age (RR: 0.64; 95% CI: 0.43-0.94; P = 0.02) with a greater reduction in CABG-only participants ≥65 years of age (RR: 0.49; 95% CI: 0.27-0.87; P = 0.01). Rehospitalization and rates of adverse events were similar across the 3 groups. CONCLUSIONS: There were no significant differences in the rate of POAF with either dose compared with placebo; however, there was a lower rate of POAF in participants ≥65 years undergoing CABG only and receiving 125 U of AGN-151607. These hypothesis-generating findings require investigation in a larger, adequately powered randomized clinical trial. (Botulinum Toxin Type A [AGN-151607] for the Prevention of Post-operative Atrial Fibrillation in Adult Participants Undergoing Open-chest Cardiac Surgery [NOVA]; NCT03779841); A Phase 2, Multi-Center, Randomized, Double-Blind, Placebo-Controlled, Dose Ranging Study to Evaluate the Efficacy and Safety of Botulinum Toxin Type A [AGN 151607] Injections into the Epicardial Fat Pads to Prevent Post-Operative Atrial Fibrillation in Patients Undergoing Open-Chest Cardiac Surgery; 2017-004399-68).

Postoperative atrial fibrillation (POAF) after cardiac surgery: clinical practice review.

Postoperative atrial fibrillation (POAF) after cardiac surgery is associated with elevated morbidity and mortality. Although current prediction models have limited efficacy, several perioperative interventions can reduce patients' risk of POAF. These begin with preoperative medications, including beta-blockers and amiodarone. Moreover, patients should be screened for preexisting atrial fibrillation (AF) so that concomitant surgical ablation and left atrial appendage occlusion can be performed in appropriate candidates. Intraoperative interventions such as posterior pericardiectomy can reduce mediastinal fluid accumulation, which is a trigger for POAF. Furthermore, many preventive strategies for POAF are implemented in the immediate postoperative period. Initiating beta-blockers, amiodarone, or both is reasonable for most patients. Overdrive atrial pacing, colchicine, and steroids have been used by some, although the evidence base is less robust. For patients with POAF, rate-control and rhythm-control strategies have comparable outcomes. Decision-making regarding anticoagulation should recognize that the stroke risk associated with POAF appears to be lower than that for general nonvalvular AF. The evidence that oral anticoagulation reduces stroke risk is less clear for POAF patients than for patients with general nonvalvular AF. Given that POAF tends to be shorter-lived and is associated with greater bleeding risks in the perioperative period, decisions regarding anticoagulation should be individualized. Finally, wearable technology and machine learning algorithms for better predicting and managing POAF appear to be coming soon. These technologies and a comprehensive clinical program could meaningfully reduce the incidence of this common complication.

Effect of preoperative vitamin D on postoperative atrial fibrillation incidence after coronary artery bypass grafting.

BACKGROUND: Post-operative atrial fibrillation (POAF) is associated with adverse long-term cardiovascular events. OBJECTIVES: This study investigated the effects of a high-dose vitamin D administered preoperatively on the postoperative atrial fibrillation (POAF) incidence in patients with vitamin D deficiency following coronary artery bypass grafting (CABG) surgery. METHODS: This randomized controlled clinical trial was conducted on 246 CABG patients with vitamin D deficiency. All patients were randomly divided into intervention and control groups including 123 cases for each group. In the intervention group, from 3 days before surgery, they received a daily dose of 150,000 units of vitamin D orally (50,000 units of Vit D tablet three times a day) and the patients in the control group received placebo tablets before surgery. All patients in the intervention group were assessed continuously for the occurrence of POAF during the recovery period. RESULTS: In terms of gender, age, and BMI there were no significant differences between intervention and control groups. Our findings showed that the use of vitamin D supplements did not cause a significant change in the duration of intubation and hospitalization. The ratio of POAF following CABG surgery in the control and treatment groups was 26% and 11.4%, respectively (odds ratio = 0.36; 95% CI = 0.18-0.72; P = 0.003). CONCLUSIONS: Our findings revealed that high-dose vitamin D supplementation before CABG surgery significantly reduced the incidence of POAF. Further multicenter randomized trials with larger sample sizes are certainly warranted to confirm our results.

Clinical Predictors of Device-Detected Atrial Fibrillation During 2.5 Years After Cardiac Surgery: Prospective RACE V Cohort.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a frequent complication after cardiac surgery that is associated with late atrial fibrillation (AF) recurrences (late-POAF) and increased morbidity and long-term mortality. OBJECTIVES: This study sought to determine device-detected POAF incidence and to identify clinical variables associated with POAF, both in patients with and without preoperative AF history. METHODS: A total of 133 consecutive patients undergoing cardiac surgery were prospectively enrolled and continuously monitored with an implantable loop recorder for 2.5 years after surgery. Preoperative transthoracic echocardiography, 12-lead electrocardiogram, blood biomarkers, and clinical data were analyzed to develop prediction models for early- and late-POAF. RESULTS: In patients without preoperative AF history, early-POAF within the first 90 postoperative days occurred in 41 (47.1%) of 87 patients. Late-POAF after the first 90 postoperative days occurred in 22 (25%) of 87 patients, and 20 of these patients also had early-POAF during the first 90 days (20 of 22 [91%]). Increased right atrial minimum volume indexed for body surface area (RAVImin) and early-POAF were independently associated with late-POAF. A prediction model for late-POAF, which included RAVImin >11 mL/m2, age >65 years, and early-POAF, achieved an area under the curve of 0.82 (95% CI: 0.72-0.92). For patients with preoperative AF-history, late-POAF recurrences were frequent (22 of 33 [67%]). Increased RAVImin was independently associated with a higher incidence of late-POAF. CONCLUSIONS: In patients with and without AF history, late-POAF recurrences are frequent, including in patients undergoing surgical AF ablation. In patients with no history of AF, late-POAF might be predicted with excellent accuracy by using a combination of preoperative variables. In patients with a history of AF, signs of advanced AF substrate (eg, increased right atrial volumes) were associated with long-term AF recurrences. [Reappraisal of Atrial Fibrillation: Interaction Between Hypercoagulability, Electrical Remodeling, and Vascular Destabilisation in the Progression of AF; NCT03124576].

Nonpharmacologic rate control of postoperative atrial fibrillation in the canine sterile pericarditis model.

INTRODUCTION: Postoperative atrial fibrillation (POAF) is common following open heart surgery, and is associated with significant morbidity. Medications used for ventricular rate control of POAF may not be effective in controlling rapid ventricular rates during the postoperative period because of increased sympathetic tone. The purpose of this study was to develop nonpharmacologic rate control of POAF by atrioventricular node (AVN) fat pad stimulation using clinically available temporary pacing wires in the canine sterile pericarditis model. METHODS: We studied 10 sterile pericarditis dogs in the closed-chest state on postoperative days 1-3. The AVN fat pad stimulation (amplitude 2-15 mA; frequency 20 Hz; pulse width 0.03-0.2 ms) was performed during sustained POAF (>5 min). We measured ventricular rate and inefficient ventricular contractions during sustained POAF and compared it with and without AVN fat pad stimulation. Also, the parameters of AVN fat pad stimulation to achieve a rate control of POAF were measured over the postoperative days. RESULTS: Eleven episodes of sustained POAF were induced in 5/10 sterile pericarditis dogs in the closed-chest state on postoperative days 1-2. During POAF, the AVN fat pad stimulation decreased the ventricular rate from 178 ± 52 bpm to 100 ± 8 bpm in nine episodes. Nonpharmacologic rate control therapy successfully controlled the ventricular rate and eliminated inefficient ventricular contractions during POAF for the duration of the AVN fat pad stimulation. The AVN fat pad stimulation output remained relatively stable over the postoperative days. CONCLUSION: During sustained POAF, nonpharmacologic rate control by AVN fat pad stimulation effectively and safely controlled rapid ventricular rates throughout the postoperative period.

Influence of epicardial adipose tissue inflammation and adipocyte size on postoperative atrial fibrillation in patients after cardiovascular surgery.

Epicardial adipose tissue (EAT) is an active endocrine organ that is closely associated with occurrence of atrial fibrillation (AF). However, the role of EAT in the development of postoperative AF (POAF) remains unclear. We aimed to investigate the association between EAT profile and POAF occurrence in patients who underwent cardiovascular surgery. We obtained EAT samples from 53 patients to evaluate gene expression, histological changes, mitochondrial oxidative phosphorylation (OXPHOS) capacity in the EAT, and protein secretion in EAT-conditioned medium. EAT volume was measured using computed tomography scan. Eighteen patients (34%) experienced POAF within 7 days after surgery. Although no significant difference was observed in EAT profile between patients with and without POAF, logistic regression analysis identified that the mRNA expression levels of tumor necrosis factor-alpha (TNF-α) were positively correlated and adipocyte size in the EAT was inversely correlated with onset of POAF, respectively. Mitochondrial OXPHOS capacity in the EAT was not associated with POAF occurrence; however, it showed an inverse correlation with adipocyte size and a positive correlation with adiponectin secretion. In conclusion, changes in the secretory profile and adipocyte morphology of the EAT, which represent qualitative aspects of the adipose tissue, were present before the onset of AF.