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.

Central venus cannulation during cardiac surgery as a possible new additional risk factor for late post-operative atrial fibrillation insurgence.

BACKGROUND: Postoperative atrial fibrillation (POAF) is the most frequent cardiac arrhythmia following cardiac operations. It has been associated with an increased risk of postoperative cerebrovascular complications, morbidity and mortality. The aim of this study is to evaluate if the type of venous cannulation to institute the cardiopulmonary bypass (CPB) during major cardiac surgery procedures can influence the rate of POAF and late FA onset. METHODS: We collected data from 2087 consecutive patients who have been operated at our Institution from January 2016 to December 2018. To obtain two homogenous groups we performed a propensity match analyzes: Group 1 for whom the blood drain of the CPB has been granted via peripheral cannulation (PC) through the right common femoral vein and Group 2 with patients who underwent central cannulation (CC) with insertion of a drainage cannula in the right atrium or in the superior and inferior vein cava. RESULTS: POAF has been observed as statistically similar between the two groups. At 1250-day follow-up, While the incidence of POAF was 2.9% and 8.7% in the PC and CC groups, respectively (p = .04). CONCLUSIONS: our data seems to show that the two groups do not differ in terms of POAF, while the CC group may have a significantly higher rate of atrial fibrillation in the follow-up period.

Increased IL-12p70 Levels in Intraoperative Pericardial Fluid Are Predictive of Postoperative Atrial Fibrillation Onset after Coronary Artery Bypass Surgery.

Background: Postoperative atrial fibrillation (POAF) is a frequent complication of heart surgery, prolonging hospital stays, as well as increasing morbidity and mortality rates. While previous studies have investigated the determinants influencing atrial fibrillation (AF) following heart surgery, the specific risk factors contributing to POAF occurrence after coronary artery bypass graft surgery (CABG) are not well understood. Here we used the human magnetic Luminex assay to assess whether biomarkers, particularly cytokines, within intraoperative pericardial fluid could serve as predictive markers for POAF onset among CABG individuals. Methods: In this study we identified 180 patients who underwent CABG with no atrial arrhythmia history. The human magnetic Luminex assay was used to quantify the levels of 36 cytokines in pericardial fluid samples collected during the surgery. The occurrence of POAF was continuously monitored, using both postoperative electrocardiograms and telemetry strips, until the time of discharge. Results: In our cohort of 124 patients, POAF was observed in 30 patients, accounting for 24.19% of the study population. These patients exhibited significantly higher levels of interleukin (IL)-12p70 in their intraoperative pericardial fluids compared to those with normal sinus rhythms (SR, p < 0.001). Subsequently, IL-12p70 was found to be an independent risk factor for POAF, and receiver operating characteristic (ROC) analysis established a cut-off threshold for predicting POAF onset of 116.435 pg/mL, based on the maximum Youden index (area under the curve: 0.816). Conclusions: this study establishes a significant association between elevated IL-12p70 levels in intraoperative pericardial fluid and the risk of POAF, particularly when IL-12p70 concentrations exceed the identified cut-off value of 116.435 pg/mL. These findings suggest that IL-12p70 levels could potentially be utilized as a predictive biomarker for the onset of POAF in patients undergoing CABG. This marker may aid in the early identification and management of patients at heightened risk for this complication.

Association of Postoperative Atrial Fibrillation Duration after Coronary Artery Bypass Grafting with Poor Postoperative Outcomes.

Background: Postoperative atrial fibrillation (POAF) has long been associated with poor perioperative outcomes after coronary artery bypass grafting (CABG). In this study, we aimed to investigate the effect of prolonged POAF durations on perioperative outcomes of CABG. Methods: This retrospective cohort study examined CABG patients enrolled at Beijing Anzhen Hospital from January 2018 to September 2021. We compared patients with POAF durations ≥ 48 hours to patients with POAF durations < 48 hours. Primary outcomes were in-hospital mortality, stroke, acute respiratory failure (ARF), acute kidney injury (AKI), and significant gastrointestinal bleeding (GIB); secondary outcomes were postoperative length of stay (LOS) and intensive care unit (ICU) duration. Associations between primary outcomes and POAF duration were determined using logistic regression and restricted cubic spline analyses. Differences in baseline characteristics were controlled using propensity score matching (PSM) and inverse probability of treatment weighting (IPTW). Results: Out of 11,848 CABG patients, 3604 (30.4%) had POAF, while 1131 (31.4%) had it for a duration of ≥ 48 hours. ARF (adjusted odds ratio [OR]: 2.96, 95% confidence interval [CI]: 1.47-6.09), AKI (adjusted OR: 2.37, 95% CI: 1.42-3.99), and significant GIB (adjusted OR: 2.60, 95% CI: 1.38-5.03) were associated with POAF durations ≥ 48 hours; however, neither in-hospital mortality (adjusted OR: 1.60, 95% CI: 0.97-2.65) nor stroke (adjusted OR: 1.28, 95% CI: 0.71-2.34) was. These results remained even following PSM and IPTW analyses. Conclusions: POAF durations longer than 48 hours were independently associated with poorer perioperative recovery from CABG, with respect to the occurrence of ARF, AKI, and GIB, as well as a longer postoperative LOS and ICU duration. However, it was not associated with greater in-hospital mortality or stroke occurrence. All these findings suggest that postoperative monitoring of POAF and positive intervention after detection may be more helpful in optimizing post-CABG patient outcomes.

Prospective Study of Risk Factors for Postoperative Atrial Fibrillation After Cardiac Surgery.

INTRODUCTION: To examine risk factors for new-onset postoperative atrial fibrillation (POAF) after cardiac surgery. METHODS: Patients enrolled in the Cardiothoracic Surgical Trials Network multicenter, randomized trial of rate control versus rhythm control for POAF were included. Predictors of POAF were determined using multivariable logistic regression. RESULTS: Among the 2104 patients who were enrolled preoperatively, 695 developed POAF (33.0%). Rates of POAF were 28.1% after isolated coronary artery bypass grafting (CABG), 33.7% after isolated valve repair or replacement, and 47.3% after CABG plus valve repair or replacement. Baseline characteristics associated with an increased risk of POAF identified on multivariable analysis included older age (odds ratio [OR] 1.57; 95% confidence interval [CI] 1.42-1.73, per 10 y), White race or non-Hispanic ethnicity (OR 1.52; CI: 1.11-2.07), history of heart failure (OR 1.55; CI: 1.16-2.08), and history of hypothyroidism (OR 1.42; CI 1.04-1.94). The type of cardiac procedure was associated with an increased risk of POAF with both isolated valve repair or replacement (OR 1.33, CI 1.08-1.64) and combined CABG plus valve repair or replacement (OR 1.64, CI 1.24-2.17) having increased risk of POAF compared to isolated CABG. No preoperative cardiac medication was associated with POAF. CONCLUSIONS: In this prospective cohort of patients, older age, a history of hypothyroidism, a history of heart failure, and valve repair or replacement, with or without CABG, and White non-Hispanic race were associated with an increased risk of POAF.

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.

Impact of preoperative inflammatory indices and postoperative pneumonia on postoperative atrial fibrillation in patients with non-small cell lung cancer: a retrospective study.

BACKGROUND: This study aimed to evaluate the impact of preoperative inflammatory indices and postoperative pneumonia (POP) on postoperative atrial fibrillation (POAF) in non-small cell lung cancer (NSCLC) patients. METHODS: All consecutive patients who underwent pulmonary resection at our hospital (January 2016-October 2019) were enrolled. Preoperative inflammatory indices, demographic data, surgical details, and postoperative conditions were analyzed. Univariate and multivariate analyses of risk factors associated with POAF were also conducted. RESULTS: Among the 382 patients included in the study, 32 (8.38%) developed POAF. Compared to non-POAF patients, POAF patients had greater incidence of POP (P = 0.09). Approximately 31 patients (96.9%) developed atrial fibrillation within three days after surgery. The POAF group had a significantly greater mean age (68.94 years) than did the non-POAF group (63 years) (P = 0.002). Additionally, compared to non-POAF patients, POAF patients exhibited an increased number of resected mediastinal lymph nodes (P < 0.001) and mediastinal lymph node stations (P < 0.001).The POAF group also had a greater intraoperative blood volume (P = 0.006), longer surgical duration (P = 0.022), and greater drainage volume (P = 0.003). IA/B stage (P < 0.001) and IIIA/B stage(P < 0.001), and lobectomy resection (P = 0.008) and wedge resection (P = 0.023) were also associated with POAF. Compared to those in the non-POAF group, the POAF group had longer postoperative hospital stays (10.54 days vs. 9 days; P = 0.001) and longer drainage times (7 days vs. 5 days; P = 0.004). Multivariate analysis revealed age, POP, and stage IIIA/B as independent influencing factors of POAF in NSCLC patients. CONCLUSION: Preoperative inflammatory indices were not significantly associated with POAF, but age, POP, and stage IIIA/B were identified as independent influencing factors. Advanced-stage NSCLC patients may have a greater susceptibility to POAF than early-stage patients, although further validation is needed. Additionally, POAF was linked to a longer postoperative hospital stay.

Impact of Limited Enhanced Recovery Pathway for Cardiac Surgery: A Single-Institution Experience.

OBJECTIVES: Enhanced recovery pathway (ERP) refers to extensive multidisciplinary, evidence-based pathways used to facilitate recovery after surgery. The authors assessed the impact that limited ERP protocols had on outcomes in patients undergoing cardiac surgery at their institution. DESIGN: A retrospective cohort study. SETTING: This study was a single-institution study conducted at a university hospital. PARTICIPANTS: Patients undergoing open adult cardiac surgery. INTERVENTIONS: Enhanced recovery pathways limited to preoperative, intraoperative, and postoperative management of pain, atrial fibrillation prevention, and nutrition optimization were implemented. MEASUREMENTS AND MAIN RESULTS: A total of 1,058 patients were included in this study. There were 374 patients in each pre- and post-ERP cohort after propensity matching, with no significant baseline differences between the 2 cohorts. Compared to the matched patients in the pre-ERP group, patients in the post-ERP group had decreased total ventilation hours (6.8 v 7.8, p = 0.006), less use of postoperative opioid analgesics as determined by total morphine milligram equivalent (32.5 v 47.5, p < 0.001), and a decreased rate of postoperative atrial fibrillation (23.3% v 30.5%, p = 0.032). Post-ERP patients also experienced less subjective pain and postoperative nausea and drowsiness as compared to their matched pre-ERP cohorts. CONCLUSIONS: Limited ERP implementation resulted in significantly improved perioperative outcomes. Patients additionally experienced less postoperative pain despite decreased opioid use. Implementation of ERP, even in a limited format, is a promising approach to improving outcomes in patients undergoing cardiac surgery.

Prolonged Systemic Inflammatory Response Syndrome After Cardiac Surgery.

OBJECTIVES: Cardiac surgery induces systemic inflammatory response syndrome (SIRS), leading to higher morbidity and mortality. There are no individualized predictors for worse outcomes or biomarkers for the multifactorial, excessive inflammatory response. The interest of this study was to evaluate whether a systematic use of the SIRS criteria could be used to predict postoperative outcomes beyond infection and sepsis, and if the development of an exaggerated inflammation response could be observed preoperatively. DESIGN: The study was observational, with prospectively enrolled patients. SETTING: This was a single institution study in a hospital setting combined with laboratory findings. PARTICIPANTS: The study included a cohort of 261 volunteer patients. INTERVENTIONS: Patients underwent cardiac surgery with cardiopulmonary bypass, and were followed up to 90 days. Biomarker profiling was run preoperatively. MEASUREMENTS AND MAIN RESULTS: Altogether, 17 of 261 (6.4%) patients had prolonged SIRS, defined as fulfilling at least 2 criteria on 4 consecutive postoperative days. During hospitalization, postoperative atrial fibrillation (POAF) was found in 42.2% of patients, and stroke and transient ischemic attack in 3.8% of patients. Prolonged SIRS was a significant predictor of POAF (odds ratio [OR] 4.5, 95% CI 1.2-17.3), 90-day stroke (OR 4.5, 95% CI 1.1-18.0), and mortality (OR 10.7, 95% CI 1.7-68.8). Biomarker assays showed that preoperative nerve growth factor and interleukin 5 levels were associated with prolonged SIRS (OR 5.6, 95%, CI 1.4-23.2 and OR 0.7, 95%, CI 0.4-1.0, respectively). CONCLUSIONS: Nerve growth factor and interleukin 5 can be used to predict prolonged systemic inflammatory response, which is associated with POAF, stroke, and mortality.

Left Atrial Strain to Predict Postoperative Atrial Fibrillation in Patients Undergoing Off-pump Coronary Artery Bypass Graft.

OBJECTIVE: Postoperative atrial fibrillation (POAF) is associated with increased morbidity, mortality, and length of hospital stay. The objective of this study was to assess the utility of left atrial strain (LAS) to predict POAF in patients undergoing off-pump coronary artery bypass grafting (OPCABG). DESIGN: Retrospective observational study. SETTING: Tertiary care hospital. PARTICIPANTS: 103 patients undergoing OPCABG. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: In addition to comprehensive transthoracic echocardiography, LAS was measured for reservoir (R), conduction (CD), and contraction (CT) components. POAF was defined as new electrocardiographic evidence of AF requiring treatment. Logistic regression was done to assess factors associated with POAF. The diagnostic accuracy of variables in predicting POAF was assessed by receiver operating characteristic analysis. POAF was documented in 24 (23.3%) patients. There was no difference in ejection fraction, average global longitudinal strain, or proportion of left ventricular diastolic dysfunction grades between patients with POAF and patients without POAF. All three components of LAS: LAS R (19.2 ± 4.7 v 23.5 ± 4.8, p < 0.001), LAS CD (8.9 ± 3.7 v 12.3 ± 4.8, p = 0.1), and LAS CT (10.3 ± 3.9 v 12.1 ± 4.1, p = 0.04), were significantly lower among patients with POAF compared with patients without POAF, respectively. According to univariate analysis, all components of LAS were statistically significant predictors of POAF. In multivariate analysis, only age (odds ratio = 1.08, p = 0.025) and LAS R (odds ratio = 0.84, p = 0.004) were independently associated with POAF. LAS R was a better predictor of POAF, with an area under the curve (AUC) of 0.758, than LAS CD (AUC = 0.67) and LAS CT (AUC = 0.62). LAS R had an optimal cutoff of 23% with sensitivity of 95.8% (confidence interval: 78.9-99.9%) and specificity of 49.4% (37.9-60.9%) to predict POAF. CONCLUSIONS: LAS R is a significant predictor of POAF, and its use can be recommended for screening of OPCABG patients at high risk of POAF.

Incidence of atrial fibrillation after esophageal cancer surgery with L-carnitine use: a preliminary single-group interventional study.

PURPOSE: We aimed to investigate the POAF rate and blood FABP4 levels after perioperative L-carnitine administration in patients with esophageal cancer. METHODS: L-carnitine (3 g in three divided doses) was administered to 15 patients 2 days before and 3 days after surgery. POAF during the study period and blood FABP4 levels (ELISA) before and after L-carnitine administration were evaluated. Accurate 95% confidence intervals (CI) for POAF incidence and changes in blood FABP4 levels were calculated. The preoperative predicted POAF rate was calculated using an application for esophageal cancer. The correlation between FABP4 levels and the predicted POAF rate was analyzed using Pearson's coefficient (r). RESULTS: Thirteen patients completed this study. The predicted POAF rate was 24% (17%, 34%) (median; interquartile range). The actual incidence of POAF was 7.7% (95% CI: 0.2-36%). Blood FABP4 levels changed from 10.3 to 7.0 ng/mL; the average change was - 3.3 (95% CI: - 6.6 to - 0.1). A positive correlation was found between preoperative FABP4 levels and the predicted POAF rates (r = 0.564). CONCLUSIONS: The POAF rate after esophageal surgery was 7.7% for L-carnitine. L-carnitine may reduce blood FABP4 levels. This preliminary study will contribute to the planning of sample sizes in future randomized trials.

Postoperative atrial fibrillation: from mechanisms to treatment.

Postoperative atrial fibrillation (POAF) is the most common type of secondary atrial fibrillation (AF) and despite progress in prevention and treatment, remains an important clinical problem for patients undergoing a variety of surgical procedures, and in particular cardiac surgery. POAF significantly increases the duration of postoperative hospital stay, hospital costs, and the risk of recurrent AF in the years after surgery; moreover, POAF has been associated with a variety of adverse cardiovascular events (including stroke, heart failure, and mortality), although it is still unclear if this is due to causal relation or simple association. New data have recently emerged on the pathophysiology of POAF, and new preventive and therapeutic strategies have been proposed and tested in randomized trials. This review summarizes the current evidence on the pathogenesis, incidence, prevention, and treatment of POAF and highlights future directions for clinical research.

Development and validation a nomogram for predicting new-onset postoperative atrial fibrillation following pulmonary resection.

BACKGROUND: The new-onset postoperative atrial fibrillation (NOPAF) following pulmonary resection is a common clinical concern. The aim of this study was to construct a nomogram to intuitively predict the risk of NOPAF and offered protective treatments. METHODS: Patients who underwent pulmonary resection between January 2018 and December 2020 were consecutively enrolled. Forward stepwise multivariable logistic regression analyses were used to screen independent predictors, and a derived nomogram model was built. The model performance was evaluated in terms of calibration, discrimination and clinical utility and validated with bootstrap resampling. RESULTS: A total of 3583 patients who met the research criteria were recruited for this study. The incidence of NOPAF was 1.507% (54/3583). A nomogram, composed of five independent predictors, namely age, admission heart rate, extent of resection, laterality, percent maximum ventilation volume per minute (%MVV), was constructed. The concordance index (C-index) was 0.811. The nomogram showed substantial discriminative ability, with an area under the receiver operating characteristic curve of 0.811 (95% CI 0.758-0.864). Moreover, the model shows prominent calibration performance and higher net clinical benefits. CONCLUSION: We developed a novel nomogram that can predict the risk of NOPAF following pulmonary resection, which may assist clinicians predict the individual probability of NOPAF and perform available prophylaxis. By using bootstrap resampling for validation, the optimal discrimination and calibration were demonstrated, indicating that the nomogram may have clinical practicality.

[New-onset postoperative atrial fibrillation following coronary artery bypass grafting: Incidence, clinical course and short-term outcomes].

INTRODUCTION: The aims of this retrospective study were to investigate the incidence, clinical course and short term outcomes of new-onset postoperative atrial fibrillation (POAF) following coronary artery bypass surgery (CABG). MATERIALS AND METHODS: A nation-wide study on 1622 patients who underwent CABG from 2006-2020 at Landspitali University Hospital. Clinical data were extracted from registries and 121 patients with pre-existing AF excluded, leaving 1501 patients for further analysis. Patient charts and postoperative ECGs were manually reviewed for determining details of POAF, which was defined as a postoperative episode of AF before discharge lasting at least 5 minutes. Patients with POAF (n=483) were compared to non-POAF patients (n=1018). RESULTS: Altogether 483 (32.2%) patients developed POAF; the annual incidence decreasing over time (tau= -0,45, p=0.023). Most patients were diagnosed on the second day postoperatively (43.5%) and over 90% were diagnosed within 4 days. The median number of POAF episodes was 3 (IQR: 1-5), the first episode lasting 1-6 hours in half of the cases and the total POAF-duration being 12 hours median (IQR: 5-30). Over 94% of cases converted to sinus rythm before discharge, with 25 (5.3%) patients being discharged in AF. Most patients were treated with beta-blockers (98.8%), amiodarone (95%) and 14.9% with electric cardioversion. POAF-patients were older, had higher EuroSCORE II and a longer hospital stay, however, they had similar rates of early postoperative stroke and 30 day mortality. CONCLUSION: The incidence of POAF remains high and was associated with prolonged hospital stay, but not significantly higher 30 day mortality or early postoperative stroke compared to patients in sinus rhythm. POAF-episodes were predominantly transient and almost 95% of patients were discharged in sinus rythm.

Evaluation of Perioperative Beta-Blockers and Factors Associated with Postoperative Atrial Fibrillation in Cardiac Surgery: A Single Center Experience.

Background: Postoperative atrial fibrillation (AF) has a complex etiology, and beta-blockers are commonly recommended for its pharmacological prevention. This study aims to assess the impact of beta-blocker therapy on postoperative AF occurrence in patients undergoing aortic valve replacement, mitral valve replacement, surgical revascularization of the myocardium, or a combination of these procedures. Methods: The study encompassed 472 patients who received aortic valve replacement, mitral valve replacement, surgical revascularization, or their combination. We evaluated the efficacy of preoperative and one-month postoperative beta-blocker administration in preventing postoperative AF, and the associated risk factors involved in the development of postoperative AF. Results: Of the total patient population, 36% experienced postoperative AF. Our study demonstrated a significant reduction in postoperative AF incidence among patients receiving beta-blocker treatment (all p-values < 0.05). Additionally, one-month post-surgery, beta-blocker treatment exerted a protective effect by maintaining the sinus rhythm (p = 0.0001). Regarding the risk factors involved in the development of postoperative AF, both age and left atrium (LA) sizeassessed pre-and postoperatively-were positively correlated with the occurrence of postoperative AF (p = 0.006). No relationship was found between leukocyte counts and AF incidence. Notably, C-reactive protein (CRP) levels were significantly elevated on the fifth postoperative day in patients with AF (p < 0.007). The duration of ischemia was significantly longer in patients with AF (p = 0.009). Conclusions: This study establishes the efficacy of perioperative beta-blocker treatment in mitigating postoperative AF. One month post-surgery, most patients under beta-blocker therapy maintained sinus rhythm, suggesting a potential long-term protective effect of beta-blockers against late-onset AF.

Postoperative Atrial Fibrillation After Surgical Aortic Valve Replacement: Amiodarone and Warfarin Use.

INTRODUCTION: The association between amiodarone treatment for postoperative atrial fibrillation (POAF) after surgical aortic valve replacement (SAVR) and both the return to normal sinus rhythm (NSR) and anticoagulation use at discharge has not been extensively studied. METHODS: We retrospectively identified all patients who underwent biological SAVR with or without concomitant coronary artery bypass grafting (CABG) at a Veterans Affairs Medical Center (2005-2015). We reviewed new-onset POAF, amiodarone use, return to NSR, and anticoagulation use with warfarin. Discharge rhythm and warfarin administration were compared among patients with POAF who were treated with amiodarone and patients who did not receive amiodarone. RESULTS: Of the 395 patients (186 AVR/coronary artery bypass grafting; 209 AVR) studied, POAF developed in 191 patients (48.0%); 80.1% (153/191) of these patients received amiodarone. Among patients treated with amiodarone, 70.6% (108/153) were in SR at the time of discharge versus 65.8% (25/38) of POAF patients who were not treated with amiodarone (P = 0.57). Among amiodarone-treated patients, 30.7% (47/153) were discharged with warfarin; among patients not treated with amiodarone, 31.6% (12/38) were discharged with warfarin (P = 0.92). Among amiodarone-treated patients discharged in NSR, 89.9% (97/108 patients) were not discharged with warfarin; among patients not treated with amiodarone who were discharged in NSR, 92% (23/25) were not discharged with warfarin (P = 0.74). CONCLUSIONS: POAF after SAVR appears common. Although amiodarone is often used for POAF patients, its use does not appear to be associated with surgeons' decision to anticoagulate patients. Surgeons' preferences for using rhythm control and antithrombotic therapy for POAF after SAVR warrant further exploration.

Mobile health vs. standard care after cardiac surgery: results of The Box 2.0 study.

AIMS: Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery, yet difficult to detect in ambulatory patients. The primary aim of this study is to investigate the effect of a mobile health (mHealth) intervention on POAF detection after cardiac surgery. METHODS AND RESULTS: We performed an observational cohort study among 730 adult patients who underwent cardiac surgery at a tertiary care hospital in The Netherlands. Of these patients, 365 patients received standard care and were included as a historical control group, undergoing surgery between December 2017 and September 2018, and 365 patients were prospectively included from November 2018 and November 2020, undergoing an mHealth intervention which consisted of blood pressure, temperature, weight, and electrocardiogram (ECG) monitoring. One physical outpatient follow-up moment was replaced by an electronic visit. All patients were requested to fill out a satisfaction and quality of life questionnaire. Mean age in the intervention group was 62 years, 275 (70.4%) patients were males. A total of 4136 12-lead ECGs were registered. In the intervention group, 61 (16.7%) patients were diagnosed with POAF vs. 25 (6.8%) patients in the control group [adjusted risk ratio (RR) of POAF detection: 2.15; 95% confidence interval (CI): 1.55-3.97]. De novo atrial fibrillation was found in 13 patients using mHealth (6.5%) vs. 4 control group patients (1.8%; adjusted RR 3.94, 95% CI: 1.50-11.27). CONCLUSION: Scheduled self-measurements with mHealth devices could increase the probability of detecting POAF within 3 months after cardiac surgery. The effect of an increase in POAF detection on clinical outcomes needs to be addressed in future research.

Effects of different doses of glucocorticoids on postoperative atrial fibrillation: a meta-analysis.

BACKGROUND: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery, and its occurrence is closely related to inflammation. This paper intends to apply meta-analysis to investigate the effect of glucocorticoids on POAF. METHODS: PubMed, Embase, Web of Science, and Cochrane Library were searched using the internationally recognized systematic evaluation and retrieval strategy. Two review authors independently selected relevant studies and extracted data based on the Cochrane handbook for systematic reviews of interventions approach. Stata 17 was used for data analysis. In the subgroup analysis, we grouped the participant data according to differences in glucocorticoids dose and type of surgery. At the same time, we also conducted a meta-analysis on the possible infection and gastrointestinal injury caused by glucocorticoids use. RESULTS: 27 studies and 14,442 patients were finally included. Results from the random-effects model indicated that the incidence of POAF was lower in glucocorticoid group (RR 0.80, 95% CI 0.71-0.92, P = 0.001). According to the subgroup analysis result, low doses of glucocorticoids reduced the incidence of POAF (RR 0.81, 95% CI 0.71-0.92, P = 0.001). The effect of high doses glucocorticoids on the POAF was not statistically significant (RR 0.81, 95% CI 0.56-1.19, P = 0.286). In the coronary artery bypass grafting (CABG) subgroup, the glucocorticoids reduced the incidence of POAF (RR 0.71, 95% CI 0.58-0.87, P = 0.001). In the CABG OR Valvular Surgery group, the effect of glucocorticoids on POAF was not statistically significant (RR 0.88, 95% CI 0.75-1.03, P = 0.108). 15 studies documented postoperative complications of infection, two studies were excluded from the system because the end point event was 0, and meta-analysis showed no increased risk of infection from glucocorticoid use (RR 0.85, 95% CI 0.68-1.06, P = 0.158). Eight studies documented the effects of glucocorticoids on gastrointestinal diseases, and meta-analysis showed no differences between the two groups (RR 1.12, 95% CI 0.83-1.50, P = 0.450). CONCLUSION: The use of glucocorticoids can reduce the incidence of POAF. The subgroup analysis result showed that low-dose glucocorticoids were more effective than high-dose glucocorticoids in inhibiting POAF. The use of glucocorticoids in CABG alone can better inhibit the occurrence of POAF. The effects of glucocorticoids on infection and gastrointestinal injury were not statistically significant. REVIEW REGISTRATION: PROSPERO, CRD42022304521.

Validation of a new species for studying postoperative atrial fibrillation: Swine sterile pericarditis model.

BACKGROUND: The canine sterile pericarditis model associated with atrial inflammation is an experimental counterpart of postoperative atrial fibrillation (POAF). However, the use of canines for research is restricted by ethics committees in many countries, and social acceptance is declining. OBJECTIVE: To validate the feasibility of the swine sterile pericarditis model as an experimental counterpart to study POAF. METHODS: Seven domestic pigs (35-60 kg) underwent initial pericarditis surgery. On two or more postoperative days in the closed-chest state, we performed electrophysiological measurements of pacing threshold and atrial effective refractory period (AERP) while pacing from the right atrial appendage (RAA) and the posterior left atrium (PLA). The inducibility of POAF (>5 min) by burst pacing was determined in both the conscious and anesthetized closed-chest state. These data were compared to previously published canine sterile pericarditis data for validation. RESULTS: The pacing threshold increased from day 1 to day 3 (2 ± 0.1 to 3.3 ± 0.6 mA in the RAA, 2.5 ± 0.1 to 4.8 ± 0.2 mA in the PLA). Also, the AERP increased from day 1 to day 3 (118 ± 8 to 157 ± 16 ms in the RAA; 98 ± 4 to 124 ± 2 ms in the PLA, both p < .05). Induction of sustained POAF occurred in 43% (POAF CL range 74-124 ms). All electrophysiologic data from the swine model were consistent with the canine model with respect to (1) the range of both pacing threshold and AERP; (2) the progressive increase in threshold and AERP over time; (3) a 40%-50% incidence of POAF. CONCLUSION: A newly developed swine sterile pericarditis model demonstrated electrophysiologic properties consistent with the canine model and patients after open heart surgery.

Evaluation of the usefulness of determining the level of selected inflammatory biomarkers and resistin concentration in perivascular adipose tissue and plasma for predicting postoperative atrial fibrillation in patients who underwent myocardial revascularisation.

BACKGROUND: The development of coronary artery disease (CAD) is related to the impaired quantity and composition of inflammatory proteins found in plasma and tissue, such as interleukin 6 (IL-6), adipokines, and resistin. Therefore, the level of plasma resistin in patients with advanced CAD could be indicative of the condition of epicardial adipose tissue and thus have an impact on the frequency and severity of postoperative complications in the form of paroxysmal atrial fibrillation. METHODS: The study included 108 patients who qualified for elective coronary artery bypass grafting (CABG) surgery from 2017 to 2020 and were categorized into two groups. The first group consisted of patients who developed atrial fibrillation in the postoperative period - the AF group, and the second group included patients who did not have arrhythmia - the non-AF group. The analysis incorporates the history, course of treatment, anthropometric characteristics of the test subjects, biochemical laboratory tests, and echocardiography. Perivascular adipose tissue (PVAT) sections were surgically harvested from the area of the left coronary trunk. RESULTS: The resistin levels in the PVAT were significantly higher in the AF group than in the non-AF group (P = 0.000015). Similarly, plasma resistin levels increased significantly in the AF group compared to the non-AF group (P = 0.044). The values of other analyzed variables were not significantly different (analysis performed using the Mann-Whitney U test). Spearman's rank-order correlation technique found a correlation between resistin in PVAT and plasma (r = 0.5933; P < 0.0001) in the whole study group, as well as in the AF group (r = 0.4782; P = 0.021) and the non-AF group (r = 0.4938; P < 0.0001). A correlation arose between the level of resistin in PVAT and the level of hsCRP (r = 0.3463; P = 0.005) in the whole study group and the non-AF group (r = 0.4448; P = 0.0011); however, no such correlation appeared in the AF group (r = 0.3076; P = 0.306). CONCLUSIONS: Elevated levels of plasma resistin, which reflect PVAT resistin levels in patients qualified for myocardial revascularisation, may be associated with postoperative atrial fibrillation complications.