Postoperative Atrial Fibrillation Patients Research Articles

Early anti-coagulation therapy in new-onset atrial fibrillation after coronary artery bypass grafting: a randomized trial pilot study

BackgroundNew-onset postoperative atrial fibrillation (POAF) is a common complication after coronary artery bypass grafting (CABG) surgery, increasing the risk of embolism and stroke. There is a lack of information on the use of anticoagulants in this context. The choice between Warfarin and Direct oral anticoagulants (DOACs) also is not well-established. This randomized study aimed to compare the feasibility and safety of Warfarin and Rivaroxaban in preventing thrombotic events in POAF patients after isolated CABG.MethodsA total of 66 patients were randomized parallelly with 1:1 allocation to receive either Rivaroxaban (n = 34) or Warfarin (n = 32). Major bleeding events within 30 days after discharge were the primary outcome. Secondary outcomes included minor bleeding events and thrombotic episodes. Clinical characteristics, medication regimens, and left atrial diameter were assessed. Statistical analyses were performed using appropriate tests.ResultsNo thrombotic episodes were observed in either treatment arm. No major bleeding events occurred in either group. Four minor bleeding events were reported, with no significant difference between the treatment groups (P = 0.6). Patients with atrial fibrillation had significantly larger left atrial diameters compared to those with normal sinus rhythm (40.5 vs. 37.8 mm, P = 0.01).ConclusionsThis pilot study suggests that Warfarin and Rivaroxaban are both safe and effective for preventing thrombotic episodes in POAF patients after isolated CABG. No significant differences in major bleeding events were observed between the two anticoagulants. These findings may support the preference for DOACs like Rivaroxaban due to their convenience and easier maintenance.Trial registrationNumber IRCT20200304046696N1, Date 18/03/2020 https//irct.behdasht.gov.ir/.

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

BackgroundThis 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.MethodsAll 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.ResultsAmong 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.ConclusionPreoperative 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.

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

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. 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. 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.

Gut microbiota metabolism disturbance is associated with postoperative atrial fibrillation after coronary artery bypass grafting

Postoperative atrial fibrillation (POAF) is a common complication after coronary artery bypass grafting (CABG) surgery. Gut microbiota and its metabolites have been implicated in the development of AF. However, whether the gut–host metabolic interaction contributes to POAF is still unknown. This study aimed to investigate the POAF-associated gut microbiota metabolism biomarkers and related risk model. The POAF (N = 30) patients and non-POAF (N = 60) patients from the discovery cohort exhibited significantly different microbiome and metabolome profiles. The differentiated features were mainly implicated in the bile acids (BAs) and short-chain fatty acids metabolism, inflammation, and oxidative stress. Random forest analysis identified the combination of five secondary BAs showed a powerful performance on predicting POAF in the discovery cohort, highlighting significant values of area under the curve (AUC = 0.954) and correct classification rate (CCR, 93.3%). In addition, the five secondary BAs-based risk model also exhibited good performance in differentiating the POAF (N = 114) and non-POAF individuals (N = 253) in an independent validation cohort (AUC = 0.872; CCR = 90.4%). This work revealed perturbed microbial and metabolic traits in POAF, providing potential avenues for the prediction and prevention of POAF after CABG.

Anticoagulation for post-operative atrial fibrillation after isolated coronary artery bypass grafting: a meta-analysis.

This study aimed to evaluate clinical outcomes in patients developing post-operative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) and characterize variations in oral anticoagulation (OAC) use, benefits, and complications. A systematic search identified studies on new-onset POAF after CABG and OAC initiation. Outcomes included risks of thromboembolic events, bleeding, and mortality. Furthermore, a meta-analysis was conducted on these outcomes, stratified by the use or non-use of OAC. The identified studies were all non-randomized. Among 1 698 307 CABG patients, POAF incidence ranged from 7.9% to 37.6%. Of all POAF patients, 15.5% received OAC. Within 30 days, thromboembolic events occurred at rates of 1.0% (POAF: 0.3%; non-POAF: 0.8%) with 2.0% mortality (POAF: 1.0%; non-POAF: 0.5%). Bleeding rates were 1.1% for POAF patients and 2.7% for non-POAF patients. Over a median of 4.6 years, POAF patients had 1.73 thromboembolic events, 3.39 mortality, and 2.00 bleeding events per 100 person-years; non-POAF patients had 1.14, 2.19, and 1.60, respectively. No significant differences in thromboembolic risks [effect size -0.11 (-0.36 to 0.13)] and mortality [effect size -0.07 (-0.21 to 0.07)] were observed between OAC users and non-users. However, OAC use was associated with higher bleeding risk [effect size 0.32 (0.06-0.58)]. In multiple timeframes following CABG, the incidence of complications in patients who develop POAF is low. The use of OAC in patients with POAF after CABG is associated with increased bleeding risk.

Atrial fibrillation post CABG and the risk of arrhythmia recurrence: the AFRODITE study

BackgroundNew-onset postoperative atrial fibrillation (POAF) after coronary artery bypass surgery (CABG) occurs with an incidence of 20–40%. The clinical relevance of POAF remains a concern, and the need for further studies regarding the clinical management of POAF is necessary. AimThe AFRODITE study, a prospective multicenter cohort study, had as its primary endpoint the evaluation of AF recurrence in patients post CABG over a one-year period. MethodsTwo hundred twenty-eight patients aged >50 years who underwent isolated CABG were included in the study. Patients were stratified into two groups, POAF and non-POAF, and followed for 12 months for AF recurrence, hospitalizations, and death. ResultsTwo hundred twenty-eight patients (mean age 67 years, 88.6% male) were included in the study. 28.5% of patients experienced at least one episode of POAF during index hospitalization (POAF group) and were compared with the non-POAF group (n = 163). Multivariate stepwise logistic regression analysis showed that the strongest prognostic parameter for POAF was the CHA2DS2-VASc score (odds ratio = 1.61, p < 0.001). POAF patients had a worse in-hospital outcome, but the incidence of long-term AF recurrence was not statistically different (3.6% vs. 4.8%, p = 0.9). ConclusionInterestingly, a one-year prospective follow-up of patients in the study did not reveal significant differences between POAF and non-POAF patients. A notable finding was that patients with a higher CHA2DS2-VASc score were more likely to develop POAF.

Predictors and mortality of new onset postoperative atrial fibrillation after STAAD surgery: a retrospective cohort study.

Data on new onset postoperative atrial fibrillation (POAF) after Stanford type A dissection (STAAD) surgery was limited. This study aimed to detect the risk factors for developing POAF after STAAD procedures and the association between POAF and in-hospital mortality. A total of 1354 patients who underwent surgical treatment for STAAD in Beijing Anzhen hospital were enrolled in this single-center retrospective study from January 2015 to October 2020. POAF were defined as atrial fibrillation/flutter requiring treatment after surgery procedure. Logistic model was conducted to detect the predictors of POAF, and inverse probability of treatment weighting (IPTW) and subgroup analysis were used to compare the mortality of POAF and non-POAF groups. There were 176 patients (13.0%) diagnosed with POAF according to the definition. Multivariate logistics analyses revealed that advanced age [odds ratio (OR), 1.07; 95% CI: 1.05-1.08; P <0.001)], creatinine (OR, 1.00; 95% CI: 1.00-1.01; P =0.001) and cross-clamp time (OR, 1.00; 95% CI: 1.00-1.01; P =0.021) were independent risk factors of developing POAF in STAAD patients. POAF patients were associated with significantly higher in-hospital mortality compared with non-POAF patients (6.5 vs. 19.9%, OR, 3.60; 95% CI: 2.30-5.54; P <0.001), IPTW and subgroup analysis had reached consistent conclusions. The incidence of POAF was 13.0% after STAAD surgery, advanced age, creatinine, and cross-clamp time were independent risk factors of developing POAF in STAAD patients. POAF is associated with increased mortality after STAAD procedures.

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.

Effects of Short-Term Episodes of Atrial Fibrillation after Coronary Artery Bypass Grafting on the Long-term Incidence of Atrial Fibrillation and Ischemic Stroke.

To explore whether postoperative atrial fibrillation (POAF) has an impact on the incidence of late atrial fibrillation (AF) and late ischemic stroke after isolated coronary artery bypass grafting (CABG) compared to non-POAF patients. A total of 243 eligible patients were followed for five years, and divided into a POAF group (n = 69) and a non-POAF group (n = 174). The primary end point was the incidence of late AF, and late ischemic stroke. Kaplan-Meier analyses and Cox proportional hazards models were used to examine whether POAF is an independent risk factor for the occurrence of late AF and late ischemic stroke. POAF patients were older than non-POAF patients. During the 5-year follow-up, the late occurrence of AF was significantly higher in POAF patients than in non-POAF (15.9% vs. 7.9% p = 0.006). There was no significant difference in the incidence of late ischemic stroke between POAF and non-POAF groups (p = 0.406). COX proportional regression analysis showed that POAF was independently associated with the late occurrence of AF (hazard ratio (HR) 3.27; 95% confidence interval (CI): 1.33-8.03, p = 0.01). POAF is an independent risk factor for the occurrence of late AF but not stroke after isolated CABG.

Impact of Oral Anticoagulation on Clinical Outcomes in Postoperative Atrial Fibrillation

IntroductionThe impact of postoperative oral anticoagulation (OAC) with warfarin on postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) was the focus of this examination of patients from the randomized endo-vein graft prospective (REGROUP) Trial. Material and methodsREGROUP was a prospective randomized Veterans Affairs cooperative study comparing endoscopic versus open vein harvest in elective CABG patients (March 2014-April 2017) at 16 Veterans Affairs facilities. This study compared new-onset POAF patients who were treated with warfarin versus no-warfarin. Outcomes included stroke during active follow-up and a major adverse cardiac event composite of mortality, acute myocardial infarction, and repeat revascularization during active and passive follow-up. ResultsOf the 316/1103 (28.6%) of REGROUP patients who developed new-onset POAF, 45 patients were excluded - mainly for preoperative warfarin use. Of the remaining 269 patients, 85 received OAC with warfarin (OAC group); 184 did not (no-OAC group). Stroke rates during active follow-up (32 [IQR 24-38] mo) were 3.5% OAC group versus 5.4% no-OAC group (P = 0.76); major adverse cardiac eventrates were 20% OAC versus 11.4% no-OAC (P = 0.06). On longer follow-up of (median 4.61 [IQR 3.9-5.1] y), discharge OAC use was associated with all-cause mortality after adjusting for Society of Thoracic Surgeons mortality risk (20.0% versus 11.4% no-OAC use; HR = 2.00, 95% CI: 1.05-3.81, P = 0.035). ConclusionsREGROUP patients with POAF treated with OAC had similar stroke and higher mortality rates versus no-OAC patients. Further investigation of the risk-benefit ratio of OAC in post-CABG patients and which POAF patient subgroups might derive the most benefit with anticoagulation appears warranted.

Abstract 12010: Duration of Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Surgery is Associated With Poor Perioperative Outcomes

Background: Postoperative atrial fibrillation (POAF) is one of the most common complications after coronary artery bypass graft surgery (CABG). It has long been associated with poor perioperative outcomes, but few studies have been carried out regarding the effect of POAF duration on those outcomes. Research Questions: Does prolonged duration of POAF have an adverse effect 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 POAF duration ≥48 hours patients with POAF duration &lt;48 hours patients. Primary outcomes examined were in-hospital mortality, stroke, acute respiratory failure (ARF), acute kidney injury (AKI), as well as significant gastrointestinal bleeding (GIB); secondary outcomes were postoperative length of stay (LOS), intensive care unit (ICU) stay. Associations between primary outcomes and POAF duration were determined using logistic regression and restricted cubic spline analyses. Results: Out of 11 848 CABG patients, 3604 (30.4%) had POAF; 1131 (31.4%) of POAF patients had it for duration ≥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), but not in-hospital mortality (adjusted OR: 1.56, 95% CI: 0.92 - 2.65) or stroke (adjusted OR: 1.29, 95% CI: 0.70 - 2.33) was associated with POAF duration ≥48 hours. These findings were still applicable, even after conducting propensity score matching and inverse probability of treatment weighting analyses. Conclusions: POAF duration longer than 48 hours was independently associated with poorer perioperative recovery from CABG, with respect to the occurance of AFR, AKI and GIB, as well as longer postoperative LOS and ICU stay. 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 could optimize post-CABG patient outcomes.

Healthcare resource utilization and costs for patients with postoperative atrial fibrillation in the United States

BackgroundPostoperative atrial fibrillation (POAF) is one of the most common complications following cardiac surgery. POAF is associated with increased hospitalization costs, but its long-term economic burden is not well defined.ObjectiveTo assess 30-day and 1-year incremental healthcare resource utilization (HRU) and costs associated with POAF in the United States (US).MethodsThis retrospective cohort study used claims data from the IBM Watson MarketScan database. A cohort of US adults aged 55--90 years who underwent open-heart surgery between 1 January 2017 and 31 December 2018 was used to compare patients who experienced POAF versus patients who did not (controls). The outcomes of interest were incremental HRU and costs, which were assessed during the index hospitalization and 30-day and 1-year postdischarge time periods. Inverse probability weighting was used to adjust for differences in baseline characteristics.ResultsA total of 8,020 patients met the study inclusion criteria with 5,765 patients in the control cohort (mean age, 63.4 years) and 2,255 patients in the POAF cohort (mean age, 65.8 years). After adjustment, patients with POAF had an index hospitalization that was 1.9 days longer (99% CI, 1.3-2.4 days; p < 0.001) and cost $13,919 more (99% CI, $2,828-$25,011; p < 0.001) than for patients without POAF. POAF patients also had significantly higher HRU at 30 days and 1-year postdischarge with incremental costs of $4,649 (99% CI, $1,479-$7,819; p < 0.001) and $10,671 (99% CI, $2,407-$18,935; p < 0.001), respectively.ConclusionPOAF following open-heart surgery poses a significant economic burden up to 1 year postdischarge.

Abstract P103: Higher Preoperative Plasma Aldosterone Concentrations Are Associated With Elevated Risk Of Atrial Fibrillation After Chronic Total Occlusion Percutaneous Coronary Intervention

Background: Postoperative atrial fibrillation (POAF) is associated with poor outcomes in patients with coronary chronic total occlusions (CTO). Aldosterone is a steroid hormone that regulates fluid and electrolyte homeostasis and is known to increase the risk of proarrhythmia. This study aimed to explore the additional value of preoperative plasma aldosterone levels for predicting POAF after CTO percutaneous coronary intervention (PCI). Methods: We conducted a prospective cohort study involving consecutive patients with a left ventricular ejection fraction (LVEF) greater than 50% requiring CTO-PCI in the First Affiliated Hospital of Chengdu Medical College. Patients were excluded if they had a history of AF, preoperative endocarditis and/or a ventricular assist device. Plasma aldosterone levels, echocardiography and transforming growth factor beta1 (TGF-β1) examination were assessed before percutaneous recanalization. The primary endpoint was the occurrence of POAF within 30 days after percutaneous recanalization. New-onset POAF after CTO-PCI was defined as any episode detected via continuous in-hospital electrocardiogram/telemetry monitoring and documented by a physician in the chart, regardless of duration or need for treatment. Results: Thirty-eight of 268 (14.2%) patients had POAF. Compared with controls, patients experiencing POAF were significantly older, had a higher body mass index, had diabetes and hypertension, and had higher preoperative plasma aldosterone levels. In logistic regression analysis, higher plasma aldosterone levels exhibited 1.75-fold higher odds (95% confidence interval [CI], 1.15-2.32, P=0.004) for the presence of POAF, which was significant in the adjusted model (odds ratio [OR], 1.82 [95% CI, 1.21-2.45], P=0.007). Reverse transcriptase PCR analysis performed on the left atrial appendage and plasma examination revealed that TGF-β1 was activated in POAF patients. Conclusion: Higher plasma aldosterone levels are associated with increased odds for POAF in patients with CTO-PCI, even in the absence of primary aldosteronism, implying that plasma aldosterone levels might be a target for POAF risk stratification after CTO-PCI.

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

IntroductionThe 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. MethodsWe 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. ResultsOf 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). ConclusionsPOAF 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.

Association between preoperative arterial stiffness and postoperative atrial fibrillation

Postoperative atrial fibrillation (POAF) is the most frequent cardiac surgery complication, associated with poor morbid-mortality. POAF pathophysiology remains unclear. Aortic stiffness has been demonstrated to increase after aortic valve replacement (AVR). Moreover, atrial fibrillation incidence has been demonstrated to be correlated with aortic stiffness in the context of AF ablation and in the general population. Our goal was to test the association between preoperative aortic stiffness indexes and postoperative atrial fibrillation onset after cardiac surgery. We explored consecutive patients referred for surgical aortic valve replacement for symptomatic, severe aortic stenosis with or without coronary bypass at the University Hospital CHU Lille. Aortic tree properties were characterized non-invasively thanks to the Sphygmocor® at the preoperative time. Postoperative atrial fibrillation was assessed by EKG monitoring from the end of surgery to hospital discharge. POAF occurred in 40 (31.2%) patients among the 128 included from January 2019 to June 2022. Preoperative aortic stiffness indexes were different between POAF and sinus rhythm (SR) patients regarding pulse wave velocity 12.3 ± 1.3 m/s vs. 10.8 ± 0.9 m/s P = 0.0002, and reflection magnitude (respectively 76 ± 7% vs. 75 ± 8%; P = 0.56). Preoperative aortic compliance was also different between SR and POAF patients (1.7 ± 0.6 mL/mmHg vs. 1.3 ± 0.7 mL/mmHg respectively; P = 0.017). Peripheral vascular resistances were 1570 ± 430 dyn.s.cm−5 in SR vs. 1640 ± 450 dyn.s.cm-5 in POAF (P = 0.0.04). There is a higher aortic stiffness in preoperative period for patient who underwent POAF after aortic valve replacement.

CE-452780-3 PREDICTORS OF ATRIAL FIBRILLATION RECURRENCE IN CARDIAC AND NON-CARDIAC PATIENTS WITH POST-OPERATIVE ATRIAL FIBRILLATION

Post-operative atrial fibrillation (POAF) is new onset atrial fibrillation (AF) that occurs within 90 days of surgical procedure. Its underlying mechanism is believed to be related to factors such as inflammation, adrenergic surplus, infections and hypoxia. The predictors of AF recurrence in POAF population are not well defined. Establishing potential predictors of AF recurrence in POAF patients could help clinicians identify patients who are at increased risk of stroke and other complications. The aim of this study is to identify the incidence and predictors of AF recurrence after 90 days in POAF patients who have undergone cardiac surgery (CS) and non-cardiac surgery (NCS). We retrospectively reviewed the medical records of patients who underwent cardiac and non cardiac surgery at Hartford Healthcare System from January 2017 to September 2021. Surgical patients with POAF during their index surgical hospitalization were identified. Of this population patients with recurrence of atrial fibrillation after 90 days were examined. We used multivariate logistic regression to identify predictors of atrial fibrillation recurrence in these patients. Out of 81,244 surgical patients, 6,138 were CS and 75,106 were NCS. Comparing CS to NCS, prevalence of POAF was 10% vs 0.3%, average age was 71 vs 73 years, male (66% vs 53%), Caucasian (92% vs 87%). The rate of AF recurrence after 90 days in CS was 105/606 (17%) and NCS was 63/231 (27%). Predictors of AF recurrence in CS were history of heart failure (OR 2.88; 95% CI 1.53 -5.34, p<0.001) and chronic obstructive pulmonary disease (COPD, OR 5.58, 95% CI 2.77-11.3, p<0.001). In the NCS group, there was a trend towards obstructive sleep apnea and hypertension being predictive of AF recurrence, but it did not meet statistical significance. At the time of admission with recurrent AF, 66% of CS and 63% of NCS patients were on anticoagulation. Our study revealed fewer patients with POAF compared to previous reports. Furthermore, the rate of recurrence is higher in NCS compared to CS patients. Additionally, COPD and heart failure were found to be independent predictors of AF recurrence in CS patients.

Molecular mechanisms of postoperative atrial fibrillation in patients with obstructive sleep apnea.

Obstructive sleep apnea (OSA) promotes atrial remodeling and fibrosis, providing a substrate for atrial fibrillation (AF). Herein, we investigate the pathophysiological mechanisms of AF in association with OSA in a cohort of cardiac surgery patients. A prospective study including patients undergoing cardiac surgery. Biomarkers reflective of AF pathophysiology (interleukin [IL-6], C-reactive protein [CRP], von Willebrand factor [vWF], N-terminal pro-brain natriuretic peptide [NT-proBNP], high-sensitivity Troponin T [hs-TnT], and Galectin-3 [Gal-3]) was assessed by functional or immunological assays. miRNAs involved in AF were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Using atrial tissue samples, fibrosis was assessed by Masson's trichrome. Connexin 40 and 43 (Cx40; Cx43) were evaluated by immunolabeling. Fifty-six patients (15 with OSA and 41 non-OSA) were included in this hypothesis-generating pilot study. OSA group had a higher incidence of postoperative AF (POAF) (46.7% vs. 19.5%; p = .042), presented an increased risk of POAF (OR 3.61, 95% CI 1.01-12.92), and had significantly higher baseline levels of NT-proBNP (p = .044), vWF (p = .049), Gal-3 (p = .009), IL-6 (p = .002), and CRP (p = .003). This group presented lower levels of miR-21 and miR-208 (both p < .05). Also, lower Cx40 levels in POAF and/or OSA patients (50.0% vs. 81.8%, p = .033) were found. The presence of interstitial fibrosis (according to myocardial collagen by Masson's trichrome) was raised in OSA patients (86.7% vs. 53.7%, p = .024). Several biomarkers and miRNAs involved in inflammation and fibrosis were dysregulated in OSA patients, which together with a higher degree of interstitial fibrosis, altered miRNA, and Cxs expression predisposes to the development of a substrate that increases the AF risk.

Gut Microbiota in Patients with Postoperative Atrial Fibrillation Undergoing Off-Pump Coronary Bypass Graft Surgery.

Post-operative atrial fibrillation (POAF) is one of the most common complications of cardiac surgery. However, the underlying mechanism is not well understood. Alterations in the gut microbiota are associated with the development of atrial fibrillation (AF). The aim of this study was to explore the relationship between gut microbiota and POAF. Fecal samples were collected before surgery from 45 patients who underwent coronary artery bypass grafting with POAF and 90 matched patients without POAF (1:2). 16S rRNA sequencing was used to detect the microbiome profiles of 45 POAF patients and 89 matched patients (one sample in the no-POAF group was deleted owing to low quality after sequencing). Plasma 25-hydroxy vitamin D level was measured by ELISA. Compared to the patients without POAF, gut microbiota composition was remarkably changed in the patients with POAF, with an increase in Lachnospira, Acinetobacter, Veillonella and Aeromonas, and a decrease in Escherichia-Shigella, Klebsiella, Streptococcus, Brevundimonas and Citrobacter. Furthermore, plasma 25-hydroxy vitamin D levels were decreased in POAF patients and negatively correlated with an abundance of Lachnospira. The gut microbiota composition between patients with and without POAF is significantly different, implying that gut microbiota may play a role in the pathogenesis of POAF. Further studies are needed to fully clarify the role of gut microbiota in the initiation of AF.

New-Onset Post-Operative Atrial Fibrillation in Patients Undergoing Coronary Artery Bypass Grafting Surgery - A Retrospective Case-Control Study.

New-onset postoperative atrial fibrillation (POAF) is a common complication following coronary artery bypass grafting (CABG) surgery. To explore predictive factors and potential mechanisms of new-onset POAF in isolated off-pump CABG patients. Retrospective observational case-control study of 233 patients undergoing isolated off-pump CABG surgery between August 2018 and July 2020 at the Department of Thoracic and Cardiovascular Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School. Associations between predictor variables and new-onset POAF were identified. The main outcome was new-onset POAF after CABG surgery. A total of 75 (32.19%) patients developed new-onset POAF after CABG surgery. The new-onset POAF patients had advanced age, higher baseline systolic blood pressure, more preoperative use of diuretic drug, more transfusion of blood products, atrial dilation and postoperative positive inotropic drug treatment. Nineteen variates entered the multivariable logistic regression model with a Hosmer-Lemeshow test score of 7.565 (P=0.477). Postoperative left atrial enlargement, postoperative drainage in the first 24 hours and total length of hospital stay were statistically significant, while postoperative right atrial enlargement (OR and 95% CI, 7.797 [0.200, 304.294], P=0.272) and left atrial enlargement (3.524 [1.141, 10.886], P=0.029) assessed by echocardiography had the largest OR value. Atrial enlargement is strongly associated with new-onset POAF in patients with isolated off-pump CABG, thus it highlights the advantage of echocardiography as a useful tool for predicting new-onset POAF. Careful monitoring and timely intervention should be considered for these patients.

Colchicine attenuates the electrical remodeling of post-operative atrial fibrillation through inhibited expression of immune-related hub genes and stabilization of microtubules.

Rationale: Acute inflammation is a major risk factor for post-operative atrial fibrillation (POAF), and epicardial adipose tissue (EAT) is considered as a source of inflammatory mediators. However, underlying mechanisms and pharmacological targets of POAF are poorly understood. Methods: Integrative analysis of array data from EAT and right atrial appendage (RAA) samples was conducted to identify potential hub genes. Lipopolysaccharide (LPS)-stimulated inflammatory models in mice and in induced pluripotent stem cell-derived atrial cardiomyocytes (iPSC-aCMs) were used to examine the exact mechanism underlying POAF. Electrophysiological analysis, multi-electrode array, and Ca2+ imaging was employed to explore the alterations of electrophysiology and Ca2+ homeostasis under inflammation. Flow cytometry analysis, histology and immunochemistry were performed to investigate immunological alterations. Results: We observed electrical remodeling, enhanced atrial fibrillation (AF) susceptibility, immune cell activation, inflammatory infiltration, and fibrosis in LPS-stimulated mice. LPS-stimulated iPSC-aCMs showed arrhythmias, abnormal Ca2+ signaling, reduced cell viability, disrupted microtubule network and increased α-tubulin degradation. VEGFA, EGFR, MMP9 and CCL2 were identified as hub genes simultaneously targeted in the EAT and RAA of POAF patients. Notably, treatment of colchicine in LPS-stimulated mice resulted in a U-shape dose-response curve, where greatly improved survival rates were observed only at doses between 0.10-0.40 mg/kg. At this therapeutic dose level, colchicine inhibited the expression of all the identified hub genes and effectively rescued the pathogenic phenotypes observed in LPS-stimulated mice and iPSC-aCM models. Conclusions: Acute inflammation promotes α-tubulin degradation, induces electrical remodeling, and both recruits and facilitates the infiltration of circulating myeloid cells. A certain dose of colchicine attenuates electrical remodeling and decreases the recurrence of AF.