Postoperative Atrial Fibrillation Research Articles

Postoperative atrial fibrillation burden and progression patterns after cardiac surgery during 2.5 years of continuous rhythm monitoring

Abstract Background Early postoperative atrial fibrillation (POAF) is a frequent complication after cardiac surgery, with an incidence of up to 50%.(1, 2) The clinical presentation of early-POAF, however, might be highly diverse, showing great individual differences in symptoms, as well as POAF-specific characteristics such as the number of episodes, duration of episodes, and the percentage of time spent in POAF (POAF-burden). It is currently unknown how these early-POAF characteristics, particularly POAF-burden, are related to the risk of developing late-POAF recurrences. Purpose To establish the association between early-POAF characteristics, in particular POAF-burden, and late-POAF occurrence and burden. Methods Patients with and without a history of AF undergoing cardiac surgery were included. Preoperatively, all patients underwent echocardiography, electrocardiography, and blood biomarker analysis. Intraoperatively, all patients received an implantable loop recorder for a period of 2.5 years. POAF was defined as an AF episode lasting at least 2 minutes, detected by the ILR algorithm, and all episodes were manually checked by the investigators. POAF-burden was calculated as the percentage of time in AF for different time intervals (early: 0-3 months, late: 3-30 months). Classification of burden was performed based on cut-off values for tertiles. Also, associations between early-POAF characteristics, such as episode duration, and the incidence of late-POAF were analyzed. Results The study population consisted of 98 patients undergoing cardiac surgery (71 without preoperative AF history and 27 with preoperative AF history), out of which 53 developed POAF. Early-POAF occurred in 46 patients, and late-POAF in 36 patients. Early-POAF was associated with an increased occurrence of late POAF after adjusting for age, sex, PAF-history, and persistent AF-history (adjusted hazard ratio [aHR] = 4.62, 95% CI: 1.93-11.05, p<0.001) (Figure 1A). Multiple regression analysis, adjusted for age, sex, PAF-history, and persistent AF-history, revealed a gradual increase in late-POAF hazard between the early-POAF burden tertiles compared to patients without early-POAF (p<0.001) (Figure 1B). Similarly, the longest individual early-POAF episode and the number of early-POAF episodes were both associated with an increased late-POAF hazard (p<0.001 and p<0.001, respectively) (Figure 1C-D). The highest POAF-burden was observed in the early postoperative phase, with a significant reduction in the late phase (p=0.007) (Figure 2A). Overall, 84 patients had no late-POAF or a reduction in POAF burden, while 14 patients showed an increase in POAF-burden compared to the early postoperative phase (Figure 2B). Conclusion Early-POAF characteristics, such as POAF-burden, are strongly associated with an increased occurrence of late-POAF. The highest POAF-burden is present in the early postoperative phase, and only a minority of patients experience an increase in late-POAF burden.Figure 1Figure 2

Postoperative atrial fibrillation is associated with late mortality independently of patient comorbidities: a systematic review and reconstructed individual patient data meta-analysis

Abstract Background Early postoperative atrial fibrillation (POAF) is the most common complication within the first days after cardiac surgery. It is hypothesized to result from perioperative stressors such as inflammation, oxidative stress, and increased adrenergic tone, along with an advanced arrhythmogenic substrate resulting from advanced age and cardiovascular comorbidities including hypertension, heart failure, or chronic obstructive pulmonary disease (COPD).[1, 2] Although prior studies have demonstrated an association between in-hospital POAF and late mortality or stroke, it is questionable whether these long-term adverse events result from the occurrence of early-POAF or, rather, from the advanced cardiovascular risk profile that partly underlies the development of early-POAF.[3] Purpose To investigate the association of early-POAF with late mortality (primary outcome) and stroke (secondary outcome) in patients undergoing cardiac surgery after adjustment for age and the cardiovascular risk profile. Methods A systematic search, covering PubMed, EMBASE, and the Cochrane Library, was conducted to identify studies reporting on late mortality after cardiac surgery in patients with and without new-onset POAF during hospitalization. Articles meeting the criteria, which included Kaplan-Meier (KM) curves along with risk tables, were included for a pooled analysis of late mortality and stroke. Individual time-to-event data were reconstructed from the KM curves and incorporated into a multivariable frailty Cox model. The model included adjustments for age, sex, preoperative cardiovascular comorbidity profile (hypertension, diabetes mellitus [DM], peripheral artery disease [PAD], history of stroke, heart failure, and COPD), type of surgery, and a frailty term (study variable). Results In total, 28 studies were included in the analysis for late mortality (N=112931), and 9 studies in the analysis for late stroke (N=35004). Overall, 31039 patients had early-POAF with a pooled incidence of 29.7% (95% CI: 25.7-34.1%). Patients developing POAF were older (68.5 vs. 64.1 years old, p<0.001), had a more frequent history of PAD (9.5% vs. 7.8%, p=0.026), a history of stroke (9.3% vs. 7.6%, p<0.001), heart failure (17.2% vs. 15.1%, p<0.001), and COPD (12.5% vs. 9.7%, p<0.001). Unadjusted analysis showed that POAF was strongly associated with increased late mortality (Hazard Ratio [HR]=1.64, 95% CI: 1.59 to 1.69, p<0.001) and late stroke (HR=1.46, 95% CI: 1.36 to 1.58, p<0.001) (Figure 1). POAF was an independent predictor for late mortality (HR=1.46, 95% CI: 1.36 to 1.58, p<0.001) but not for late stroke (HR=1.10, 95% CI: 0.85 to 1.43, p=0.48) after adjustment for age, cardiovascular comorbidity profile, type of surgery, and frailty (study term). Conclusion Early-POAF after cardiac surgery is an independent predictor of mortality in the years following discharge after cardiac surgery, regardless of age, cardiovascular comorbidity profile, and type of surgery.Figure 1

Post-operative atrial fibrillation after noncardiac surgery: diagnostic role of ambulatory rhythm monitoring for recurrent arrhythmia after hospital discharge

Abstract Introduction Postoperative atrial fibrillation (POAF) after noncardiac surgery constitutes 10-15% of all cases of incident atrial fibrillation (AF) in the community and has been associated with an increased risk of stroke. The risk of subsequent AF among patients with POAF is not well defined. Purpose To evaluate the role of systematic 30-day electrocardiographic (ECG) monitoring in the detection of AF recurrence after POAF. Methods In a prospective interventional study, patients who underwent major noncardiac surgeries and had new AF documented by ECG in the post-operative period between May 2022 and April 2023 were identified. For these patients, a 30-day ambulatory ECG monitor was recommended upon discharge, with final ordering deferred to the primary inpatient teams. Rates of recurrent AF of any duration detected by 30-day monitoring plus routine care versus routine care alone after the surgery were compared. Results Eighty-five patients with new-onset POAF were included (mean age 72 years, male 67%). Of these, 35 (41%) patients underwent up to 30 days [median 23 (IQR 6-27) days] of continuous ECG monitoring after hospital discharge. There were no significant differences in baseline characteristics between patients who did or did not undergo monitoring (Table 1). During median 281 (IQR 197-385) days of follow-up, recurrent AF was documented in 14/35 (40%) patients in the monitoring group as opposed to 7/50 (14%) patients in the usual care group (log-rank p=0.003, Figure 1). The median time from day of surgery until documented AF recurrence was 25 (IQR 6-53) days in the monitoring group and 66 (IQR 25-145) in the usual care group. Overall, 81% of recurrent AF events in both groups were detected in the first 3 months after surgery. The median burden of AF in the cardiac monitoring group was 7% (IQR 1-15), with the longest AF event lasting a median of 6 (IQR 2-18) hours. Anticoagulation for AF was prescribed in 24/64 (37%) patients with POAF without recurrence and in 16/21 (76%) patients with recurrent AF. Conclusion Recurrent AF following POAF is common and detected most frequently in the first 3 months after noncardiac surgery. Systematic ambulatory rhythm monitoring is associated with a higher rate of AF detection following hospital discharge and may identify a patient subgroup who might benefit from anticoagulation therapy.Table 1Figure 1

Predicting post-operative atrial fibrillation after cardiac surgery using an artificial intelligence-enabled electrocardiogram algorithm

Abstract Introduction Postoperative atrial fibrillation (POAF) is common after cardiac surgery and is associated with adverse outcomes. Systematic monitoring of POAF is cumbersome, specifically beyond discharge. Therefore, risk stratification may aid to identify patients at high risk of POAF and guide monitoring strategies alongside preventive measures. However, the performance of bedside risk stratification models reliant on clinical risk factors remained underwhelming, necessitating the exploration of more sophisticated models that maintain clinical applicability. Hence, artificial intelligence algorithms (AI) have been suggested to reinforce or replace clinical risk scores. As such, a deep neural network (DNN) algorithm was developed to identify patients with AF based on a 12-lead electrocardiogram (ECG) in sinus rhythm. Whether this algorithm can identify patients at high risk of POAF remains unknown. Purpose To evaluate the usability of an AI-enabled ECG algorithm, that was trained to predict AF in non-surgical conditions, for the prediction of POAF. Methods This study retrospectively analyzed data from the SURGICAL-AF trial that monitored patients after cardiac surgery. The inclusion criteria for this subanalysis comprised: (1) patients without a history of AF prior to cardiac surgery; (2) availability of the raw data of a pre-operative 12-lead ECG in sinus rhythm; and (3) patients with POAF (during hospitalization or up to 91 days after discharge) or patients having completed PPG-based rhythm monitoring per protocol. The AF-risk score was calculated by the DNN described elsewere.1 Results In total, 127 patients (mean [SD] age, 63.4 [8.4] years; 30 women [23.6%];, median [interquartile range] CHA2DS2-VASc score, 2 [1-3]) complied with the inclusion criteria, out of the 450 patients randomized in the SURGICAL-AF trial. Testing the DNN on the last ECG before cardiac surgery resulted in an area under the receiver operating curve (AUC) of 0.66 (95% CI, 0.56 - 0.77) and an area under the precision-recall curve of 0.57 (95% CI, 0.42 -0.72). The optimal cut of score resulted in a sensitivity of 64.3% (95% CI, 48.0%-78.4%), specificity of 64.7% (95% CI, 53.6%-74.8%), accuracy of 0.65 (95% CI, 0.56 - 0.73), F1-score of 54.5% (95% CI, 42.9% - 66.8%), positive predictive value of 47.4% (95% CI, 34.0%-61.0%), and negative predictive value of 78.6% (95% CI, 67.1%-87.5%). POAF occurred within three months after cardiac surgery in 23 patients out of 57 patients classified in the high-risk group (40.4%) versus 15 patients (21.4%) out of 70 patients classified in the low-risk group (hazard ratio, 2.2; 95% CI, 1.2 – 4.3; P-value = 0.020). Conclusions The AI-enabled ECG algorithm, trained to predict AF on a pre-operative sinus rhythm ECG, was able to identify POAF with an accuracy comparable to existing clinical risk scores. Further studies are needed to determine whether the DNN score can be used as an independent predictor and improve existing risk scores.

PET-MRI Imaging to assess severity and distribution of atrial fibrosis in atrial fibrillation

Abstract Background Atrial fibrosis is a major determinant of atrial fibrillation (AF) susceptibility and ablation targeting fibrotic areas to suppress AF revealed by magnetic resonance imaging (MRI) was considered a promising approach to treat persistent AF; however, its outcome has been disappointing. We sought to develop a new imaging modality to detect the severity and distribution of atrial fibrosis. Methods This study enrolled 19 healthy volunteers and 85 patients with various cardiovascular (CV) diseases of whom 22 had persistent AF. Each patient underwent 18F-labeled aluminum fluoride targeting fibroblast activation protein inhibitor (18F-AlF-FAPI)-positron emission tomography - magnetic resonance imaging (PET-MRI). Left atrial appendage tissue biopsied at 18F-FAPI-uptake positive and negative sites was stained with Masson trichome to detect fibrosis (N=10). We compared cardiac atrial 18F-AlF-FAPI-PET-MRI imaging among healthy individuals, patients without AF and patients with persistent AF as well as patients developing and not developing postoperative AF (POAF). Results Degree of fibrosis based on Masson staining was consistent with 18F-FAPI-uptake (P<0.05). Whereas 18F-FAPI uptake was essentially undetectable in healthy volunteers, in patients with CV diseases, 18F-FAPI uptake was present in all atrial chambers. Patients with persistent AF had the greatest and most widespread uptake (P<0.001), including left atrium (P=0.001), right atrium (P<0.001), left atrial appendage (P=0.007), right atrial appendage (P<0.001), and left atrial posterior wall (P=0.004). 18F-FAPI-uptake did not differ between those with versus without POAF. Conclusions 18F-AlF-FAPI-PET-MRI imaging detected atrial fibrosis in patients with various CV diseases; patients with persistent AF exhibit severe and widespread fibrosis, while POAF is not associated with increased 18F-FAPI uptake.

Association of the pattern of new-onset post-operative atrial fibrillation with adverse clinical events over 1 year follow-up: insights from the VISION Cardiac Surgery Cohort

Abstract Background New-onset post-operative atrial fibrillation (AF) affects approximately 1 in 3 patients after cardiac surgery and is associated with adverse outcomes. Whether the amount of time spent in AF is associated with outcomes is unknown. Methods VISION Cardiac Surgery was an international, prospective cohort of patients who underwent cardiac surgery in 12 countries. We divided participants according to their pattern of AF: no new-onset AF, duration <24 h, duration 24-48 h, duration 48-72 h, duration >72 h and discharged in AF. We created a separate category for those who received electrical cardioversion. We excluded participants with a history of AF before surgery and participants with unknown duration of AF. We assessed the association of different patterns of AF, as compared to no AF, with clinical events occurring between 30 days post-operatively and 1 year of follow up. For each outcome, we created a Cox proportional hazards model adjusted for CHA2DS2-VASc score, smoking, hemodialysis, prior cardiac surgery, surgery type and antithrombotic use at hospital discharge (oral anticoagulation alone, oral anticoagulation plus antiplatelet, antiplatelet alone, or none). Results Among 12,234 eligible participants, 3,887 (30.3%) had new-onset post-operative AF and 3,711 had a known duration of AF. The proportion of patients with new-onset AF who were discharged from hospital on oral anticoagulation was 39%. Table 1 displays event rates by AF pattern. Compared to participants without AF, we observed a higher risk of a composite of stroke or vascular death at one year in participants with estimated AF duration >72 h (3.9%, adjusted hazard ratio (aHR) 1.72; 95% CI 1.03-2.87) and in those who underwent electrical cardioversion (3.7%, aHR 2.18; 95%CI 1.16-4.11). Only AF duration >72 h was associated with an increased risk of stroke (2.1%; aHR 2.42; 95%CI 1.15-5.09). We observed a higher risk of all-cause mortality in participants who were in AF at hospital discharge (4.1%, aHR 1.83; 95%CI 1.10-3.05) and in participants who received electrical cardioversion (5.8%, aHR 2.81; 95%CI 1.67-4.73). Only being in AF at discharge was associated with an increased risk of heart failure (3.8%; aHR 2.63; 95% CI 1.49-4.63). All patterns of AF were associated with AF detection in follow-up, with the strongest associations observed in participants who were in AF at hospital discharge (31.8%, aHR 73.4; 95%CI 51.4- 105.0) and in those who received electrical cardioversion (12.5%, aHR 17.9; 95%CI 11.1-28.8). Conclusions Among patients with new-onset post-operative AF following cardiac surgery, duration of AF >72 h, electrical cardioversion and being in AF at discharge are all markers of adverse events in the year following surgery. All patterns of AF confer a higher risk of AF detection in follow-up. Duration and treatment of early post-operative AF may have implications regarding the longer-term risk of adverse outcomes and recurrent AF.

Increased circulating BMP10 levels are associated with late postoperative atrial fibrillation after cardiac surgery and left atrial endomysial fibrosis

Abstract Background Serum bone morphogenetic protein 10 (BMP10) levels are a marker for history of atrial fibrillation (AF) and for major adverse cardiovascular events in AF-patients, including stroke, recurrence after catheter ablation, and mortality. The predictive value of BMP10 in patients undergoing cardiac surgery and association with morphological properties of atrial tissue are unknown. Objective To study the correlation between BMP10 levels and pre-operative 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). Pre-operative blood biomarkers were analyzed, left (n=114) and right (n=125) atrial appendage biopsies were histologically assessed following WGA-staining, and post-operative rhythm was monitored continuously with implantable loop recorders (n=134, 2.5yrs). Results Multiple logistic regression indicated that BMP10 accurately predicts a history of persistent AF (OR=1.24, 95%CI: 1.10-1.40, p=4.32e-4), similar to NT-pro-BNP. BMP10 levels were associated with increased late-POAF90 occurrence after adjusting for age, sex, AF history, and early-POAF occurrence (HR=1.07 [per 0.1ng/ml increase], 95%CI: 1.00-1.14, p=0.04). Left atrial endomysial fibrosis (St.β=0.22, p=0.04), but not overall fibrosis (St. β= , p=), was associated with circulating BMP10, after adjusting for age, sex, AF history, reduced LVF, and valvular surgery indication. Conclusion Increased BMP10 levels were associated with persistent AF-history, increased late-POAF incidence, and LAA endomysial fibrosis in a diverse population of patients undergoing cardiac surgery.

Direct oral anticoagulants versus vitamin K antagonists as stroke prevention in atrial fibrillation after cardiac surgery: a systematic review and meta-analysis

Abstract Background Cardiothoracic surgery guidelines advocate the use of vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) in the first days to months after major cardiac surgery. No recommendations on choice of anticoagulant in the first months after cardiac surgery have been issued since 2008, before the use of direct oral anticoagulants (DOACs). The basis for this is a lack of data on the safety and efficacy of DOACs after cardiac surgery. Purpose To systematically assess and meta-analyze the existing evidence on the effect of DOACs compared with VKAs on efficacy and safety after cardic surgery. We hypothesized that DOACs are non-inferior to VKAs in the setting of AF after cardiac surgery. Methods We searched Ovid MEDLINE, Ovid EMBASE, the Cochrane Central Register of Controlled trials and Clinicaltrials.gov from inception till 20 June 2023 and screened references in relevant reviews as grey literature search. Observational studies and randomized controlled trials comparing DOACs with VKAs for stroke prevention in patients with (postoperative) atrial fibrillation after cardiac surgery were included, focusing on procedures through thoracoscopy or thoracotomy. Outcomes of interest included thromboembolic events, all-cause stroke, major bleeding and mortality up to 6 months after cardiac surgery and admission duration. A random effects model was used to determine pooled treatment effects. The level of evidence was rated following the GRADE recommendations. Results We identified 4,146 records of which ten were included, together reporting on > 30,000 patients. There were no significant differences in thromboembolic events (OR 0.98; 95% CI 0.61-1.58; I^2 0%; GRADE: very low), all-cause stroke (OR 1.14; 95% CI 0.51-2.54; I^2 0%; GRADE: very low), major bleeding (OR 0.91; 95% CI 0.51-1.62; I^2 53%; GRADE: very low), all-cause mortality (OR 1.00; 95% CI 0.73-1.37; I^2 0%; GRADE: low), admission duration (MD -0.33; 95% CI -1.16 – 0.49; I^2 0%; GRADE: very low) between DOACs and VKAs in the first 6 months after cardiac surgery. Conclusion Efficacy and safety of DOACs as stroke prevention in AF following cardiac surgery were similar to that of VKAs in ten studies comprising more than 30,000 patients. Based on the existing literature, there is insufficient evidence to recommend one class of oral anticoagulants over another in the first months after cardiac surgery.Forest plot of primary outcomes

Perioperative administrations of omega three unsaturated fatty acids for reduction of postoperative atrial fibrillation in coronary artery bypass surgeries.

Perioperative administrations of omega three unsaturated fatty acids for reduction of postoperative atrial fibrillation in coronary artery bypass surgeries.

Circadian occurence patterns of atrial fibrillation after cardiac surgery during 2.5 years of continuous rhythm monitoring

Abstract Background Atrial fibrillation (AF) is a common complication after cardiac surgery, and current theories suggest that the autonomic nervous system plays a major role in the development of early postoperative AF (early-POAF).(1) However, its role in late recurrences is still unknown. Previous studies in non-surgical patients have revealed distinct preferential patterns of AF occurrence, such as adrenergic/daytime AF or nocturnal AF.(2, 3) Nevertheless, circadian onset patterns for POAF have never been studied before. Purpose To establish the circadian occurrence patterns of POAF after cardiac surgery during 2.5 years of continuous rhythm monitoring. Methods Patients with and without a history of AF undergoing cardiac surgery were included. Continuous rhythm monitoring was performed over a period of 2.5 years. POAF was defined as an AF episode lasting 2 minutes or longer, detected by the ILR algorithm, and all episodes were manually checked by the investigators. Circadian distribution of AF episode onset was presented in circadian plots for the early postoperative phase (first 90 days) and late postoperative phase (after the first 90 days). Additionally, comparisons for circadian occurrence patterns were made between early and late POAF, after dividing the daytime period into four equal time intervals (night = 12 a.m. to 5.59 a.m., morning = 6 a.m. to 11.59 a.m., afternoon = 12 p.m. to 5.59 p.m., evening = 6 p.m. to 11.59 p.m.), both in patients with and without a preoperative AF history. Results The study population consisted of 98 patients (71 without a preoperative AF history and 27 with a preoperative AF history), of which 53 developed POAF (29 without a preoperative AF history and 24 with a preoperative AF history), resulting in a total of 3607 confirmed AF episodes (Figure 1). Early-POAF occurred in 46 patients, while late-POAF occurred in 36 patients. In both patients with and without AF history, the majority of early-POAF episodes occurred between 12 a.m. and 12 p.m. (59.2% and 55.9%, respectively) (Figure 2). In patients without AF history, late-POAF occurred predominantly in the evening (26.7%), particularly episodes lasting between 10 and 360 minutes, and in the afternoon (32.3%), with a greater number of episodes lasting <10 minutes (Figure 2). Patients with AF history experienced most late-POAF episodes at night (26.4%) and during the morning (33.1%), with a peak of short episodes (<10 minutes) in the morning (Figure 2). The circadian distribution was significantly different between early- and late-POAF for both patients with and without AF history (p<0.001 and p<0.001, respectively). Conclusion In patients without a preoperative AF history, early-POAF showed a more heterogeneous circadian occurrence pattern compared to late-POAF, which occurred mostly in the evening and afternoon. In patients with a preoperative AF history, POAF initiated mostly during the night and in the morning.Figure 1Figure 2

Right atrial endomysial fibrosis is associated with higher POAF-burden

Abstract Background Atrial endomysial fibrosis, rather than overall connective tissue content, determines the complexity of conduction in human atrial fibrillation (AF). Moreover, the AF-specific blood biomarker BMP10 is associated with atrial endomysial fibrosis, but not overall connective tissue content. It is unclear whether pre-operative atrial endomysial fibrosis predicts post-operative AF (POAF) incidence and burden. Objective To determine the predictive value of atrial fibrosis for early and late POAF burden. Methods Patients with and without AF history were included in the RACE V tissue bank study (n=134). Post-operative rhythm was monitored continuously for 2.5 years with implantable loop recorders. Late POAF-burden was investigated following a 90-day blanking period. Left (n=89) and/or right (n=92) atrial appendage biopsies (LAA/RAA) were snap-frozen and histologically investigated following WGA-staining. Results Logistic regression, corrected for age, sex and AF history, showed that left (st.β = 0.54 [0.23-0.85], p=0.001) and right (st.β=0.35 [0.07-0.64], p=0.017) atrial endomysial fibrosis were associated with early POAF burden in the blanking period. Only right atrial endomysial fibrosis, however, predicted late POAF-burden (st.β=0.44 [-], p=0.009). Adjusted Cox proportional hazards analyses indicated that patients in the highest tertile of right atrial endomysial fibrosis, in particular, are at risk for late POAF (HR T3 vs T1: 2.47 [1.18-5.17], p=0.016, Fig 1). Overall connective tissue content in both atria was not associated with POAF-burden. Conclusion Patients with higher levels of right atrial endomysial fibrosis are at risk for developing late POAF with a higher POAF-burden.Figure 1

Maintenance of beta-blockers and cardiac surgery-related outcomes: a prospective propensity-matched multicentre analysis

BackgroundWe investigated the effects of maintaining beta-blockers on the day of surgery on the incidence of atrial fibrillation and postoperative acute kidney injury (AKI) in patients undergoing cardiac surgery. MethodsWe conducted a multicentre prospective observational study with propensity matching on patients treated with beta-blockers. We collected their baseline patient characteristics, comorbidities, and operative and postoperative outcomes. The endpoints were postoperative atrial fibrillation and AKI after cardiac surgery. ResultsOf the 1789 included patients, propensity matching led to 583 patients in each group. Maintenance of beta-blockers was not associated with a reduced risk of atrial fibrillation (odds ratio: 0.86 [95% confidence interval 0.66–1.14], P=0.335; 141 patients [24.2%] vs 126 patients [21.6%]). Sensitivity analysis did not demonstrate association between beta-blocker maintenance and atrial fibrillation after cardiac surgery (odds ratio: 0.93 [95% confidence interval: 0.72–1.22], P=0.625). Maintenance of beta-blockers was associated with a higher rate of norepinephrine use (415 [71.2%] vs 465 [79.8%], P=0.0001) and postoperative AKI (124 [21.3%] vs 159 [27.3%], P=0.0127). No statistically significant difference was observed in ICU length of stay. ConclusionsMaintenance of beta-blockers on the day of surgery was not associated with a reduced incidence of postoperative atrial fibrillation. However, maintenance of beta-blockers was associated with increased usage of vasopressors, potentially contributing to adverse postoperative renal events. Clinical trial registrationNCT04769752.

Incidence and predictors of post-surgery atrial fibrillation occurrence: A cohort study in 53,387 patients.

Atrial fibrillation (AF) represents the most common arrhythmia in the postoperative setting. We aimed to investigate the incidence of postoperative AF (POAF) and determine its predictors, with a specific focus on inflammation markers. We performed a retrospective single tertiary center cohort study including consecutive adult patients who underwent a major surgical procedure between January 2016 and January 2020. Patients were divided into four subgroups according to the type of surgery. Among 53,387 included patients (79.4% male, age 64.5 ± 9.5 years), POAF occurred in 570 (1.1%) with a mean latency after surgery of 3.4 ± 2.6 days. Ninety patients died (0.17%) after a mean of 13.7 ± 8.4 days. The 28-day arrhythmia-free survival was lower in patients undergoing lung and cardiovascular surgery (p < .001). Patients who developed POAF had higher levels of C-reactive protein (CRP) (0.70 ± 0.03 vs. 0.40 ± 0.01 log10 mg/dl; p < .001). In the multivariable Cox regression analysis, adjusting for confounding factors, CRP was an independent predictor of POAF [HR per 1 mg/dL increase in log-scale = 1.81 (95% CI 1.18-2.79); p = .007]. Moreover, independent predictors of POAF were also age (HR/1 year increase = 1.06 (95% CI 1.04-1.08); I < .001), lung and cardiovascular surgery (HR 23.62; (95% CI 5.65-98.73); p < .001), and abdominal and esophageal surgery (HR 6.26; 95% CI 1.48-26.49; p = .013). Lung and cardiovascular surgery had the highest risk of POAF in the presented cohort. CRP was an independent predictor of POAF and postsurgery inflammation may represent a major driver in the pathophysiology of the arrhythmia.

Model for predicting the recurrence of atrial fibrillation after monopolar or bipolar radiofrequency ablation in patients with AF and mitral valve disease

ObjectivesThis study aimed to identify the risk factors for postoperative atrial fibrillation in patients with valvular atrial fibrillation, and establish predictive models of atrial fibrillation recurrence.MethodsOverall, 224 patients who underwent radiofrequency ablation of atrial fibrillation from November 2014 to November 2020 were included. The statistical package for social sciences, X-tile, and R-studio were used for statistical analysis.ResultsPatients were divided into training and validation sets according to a ratio of 3:1. The training set was analysed using univariate and multivariate Cox regression analysis and showed that preoperative uric acid > 401 μmol/L (P = 0.006), B-type natriuretic peptide > 202 ng/L (P = 0.042), hypersensitivity C-reactive protein > 6.1 mg/L (P = 0.026), erythrocyte sedimentation rate > 7.0 mm/h (P = 0.016), preoperative left atrial diameter > 48 mm (P = 0.031) were significantly correlated with the recurrence of atrial fibrillation after radiofrequency ablation in patients with valvular atrial fibrillation. In the training set, a Cox regression model of the five related factors was established using the R language. The C-index of the model was 0.82, and the area under the receiver operating characteristic curve was 0.831 (P < 0.001). Internal and external verification was performed in the training and validation sets, respectively, and both showed that the fit of the verification curve was relatively good at 3 months, 6 months, 1 year, and 3 years postoperatively. After calculating the weight of each related factor using the nomogram, a new risk predictive model (BLUCE) for postoperative atrial fibrillation was established.ConclusionsIn patients with atrial fibrillation, preoperative uric acid, B-type natriuretic peptide, hypersensitivity C-reactive protein, erythrocyte sedimentation rate, and left atrial diameter are risk factors for atrial fibrillation or atrial flutter recurrence after radiofrequency ablation. The BLUCE predictive model can distinguish high-risk groups of postoperative atrial fibrillation. High-risk patients in the BLUCE model were more likely to experience recurrence of atrial fibrillation after radiofrequency ablation and a low possibility of maintaining sinus rhythm.

Atrial Fibrillation After Coronary Artery Bypass Grafting and Its Relationship with Hospital Complications in São Paulo State.

Atrial fibrillation is the main complication in the postoperative period of cardiovascular surgery. Its genesis is multifactorial, so its rapid identification to mitigate the associated risks is essential. To evaluate the incidence of atrial fibrillation in patients undergoing coronary artery bypass grafting (CABG) and its relationship with other complications in our setting. This is a multicenter, observational study involving patients undergoing isolated CABG between 2017 and 2019 with data from the Registro Paulista de Cirurgia Cardiovascular (or REPLICCAR II). Variables were prospectively collected in REDCap following the definitions given by version 2.73 of the Society of Thoracic Surgeons Adult Cardiac Surgery Database. Data were collected with prior authorization from the local ethics committee and analyses performed in R software. A total of 3,803 patients were included, of these 605 had postoperative atrial fibrillation (POAF). In order to adjust the groups, propensity score matching was used. Such analyses resulted in 605 patients in each group (without POAF vs. with POAF). Among patients with POAF, the mean age was 67.56 years, with a prevalence of males (73.6%, 445 patients). Patients belonging to the group with POAF had a mortality rate of 9.26% (P=0.007), longer ventilation time (P<0.001), pneumonia (P<0.001), and sepsis (P<0.001). In multiple analysis, acute renal dysfunction (P=0.032) and longer intensive care unit stay (P<0,001) were associated with the presence of POAF. POAF in CABG is associated with longer intensive care unit and hospital stay, as well as renal dysfunction, pneumonia, and in-hospital mortality.

Effects of Preoperative Nutritional Status and Lymphocyte Count on the Development of Early-term Atrial Fibrillation After Coronary Artery Bypass Grafting: A Retrospective Study.

Although there are publications in the literature stating that parameters related to the nutritional status of patients are associated with the clinical outcomes of those with coronary artery disease, it is also stated that there is insufficient data on the relationship between nutritional indices and long-term outcomes and major adverse cardiovascular events in patients undergoing isolated coronary artery bypass grafting. This retrospective study was conducted with patients who underwent isolated elective on-pump coronary artery bypass grafting in our hospital. Patients who underwent emergency coronary artery bypass grafting or those with known atrial fibrillation in the preoperative period were excluded. Patients were analyzed and compared in two groups according to the development of postoperative atrial fibrillation. The data of 93 coronary artery bypass grafting patients (71 [76%] males) with a mean age of 62.86 ± 9.53 years included in the study were evaluated. Both groups had similar preoperative ejection fraction value, hemoglobin level, age, number of distal bypasses, and postoperative mortality rates. Although the mean cardiopulmonary bypass and aortic cross-clamping times were higher in Group 1, they were not statistically significant. In our study, the mean prognostic nutrition index value was 51.76 ± 3002. According to our study results, there was no statistically significant difference between prognostic nutrition index values and the development of atrial fibrillation after coronary artery bypass grafting, which is similar to some publications in the literature. We think that it would be beneficial to conduct randomized studies involving more patients on this subject.

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

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. 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. 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). 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.

New-Onset Atrial Fibrillation Is a Red Flag to Microvascular Free Tissue Transfer Failure in Head and Neck Cancer Patients.

Postoperative new-onset atrial fibrillation (AF) has been shown to be associated with increased surgical morbidity and mortality following cancer ablation surgery. However, evidence of new-onset AF's impact on surgical outcomes in head and neck cancer patients undergoing tumor ablation and microvascular free tissue transfer remains scarce. This study aims to evaluate the association between AF and surgical outcomes in these patients. We enrolled head and neck cancer patients who underwent tumor ablation reconstructed with microvascular free tissue transfer from the National Health Insurance Research Database (NHIRD). Patients were grouped into the following: (1) without AF, (2) new-onset AF, and (3) preexisting AF. The groups were matched by propensity score based on age, gender, cancer stage, and comorbidities. The primary outcome was postoperative complications, whereas all-cause mortality was the secondary outcome. In total, 26,817 patients were included in this study. After matching, we identified 2,176 (79.24%) patients without AF, 285 (10.37%) with preexisting AF, and 285 (10.37%) with new-onset AF. Our results demonstrated that the free flap failure rate was twofold escalated in patients with new-onset AF (9.8%) compared to those without AF (5.4%) or preexisting AF (5.3%; p = 0.01). However, we did not identify significant differences among other postoperative complications across groups. Additionally, we found that the risk of all-cause mortality was significantly elevated in patients with preexisting AF (p < 0.001) compared to those without AF or new-onset AF. Our study demonstrated that new-onset AF is associated with an increased risk of flap failure and could serve as a predictor. On the other hand, all-cause mortality in patients with preexisting AF was significantly elevated. Close postoperative monitoring in patients with new-onset and preexisting AF is crucial to identify any potential adverse effects.

Improved Early Outcomes With Off-Pump Coronary Artery Bypass Grafting in Patients With Left Ventricular Dysfunction: A Systematic Review and Meta-Analysis.

The ongoing debate surrounding coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass persists, particularly in individuals with left ventricular dysfunction. The objective of this study was to evaluate the safety and efficacy of these 2 strategies through a comprehensive meta-analysis of existing studies. A systematic search of PubMed, EMBASE, Web of Science, and the Cochrane Central Registry was conducted from inception to July 2023. The primary focus was on studies comparing on-pump versus off-pump CABG as the primary treatment for multivessel coronary artery disease in patients with left ventricular dysfunction (ejection fraction ≤40%), with mortality as the primary outcome. The meta-analysis included 26 studies with a total of 35,863 patients. The results revealed a significant reduction in mortality risk [risk ratio (RR), 0.75; 95% confidence interval (CI), 0.60-0.93; P = 0.009] and other perioperative morbidities associated with off-pump CABG. These included stroke (RR, 0.67; 95% CI, 0.54-0.82; P = 0.0002), myocardial infarction (RR, 0.74; 95% CI, 0.56-0.97; P = 0.03), pulmonary complications (RR, 0.71; 95% CI, 0.55-0.92; P = 0.010), postoperative transfusion (RR, 0.70; 95% CI, 0.55-0.88; P = 0.002), neurological dysfunction (RR, 0.80; 95% CI, 0.64-1.00; P = 0.05), infection (RR, 0.74; 95% CI, 0.56-0.97; P = 0.03), renal failure (RR, 0.79; 95% CI, 0.67-0.95; P = 0.010), and reoperation for bleeding (RR, 0.66; 95% CI, 0.52-0.84; P = 0.0006). However, no significant difference was observed between the 2 groups regarding postoperative atrial fibrillation (RR, 0.97; 95% CI, 0.84-1.12; P = 0.69). In conclusion, off-pump CABG demonstrates a lower perioperative mortality risk and improved overall early outcomes compared with on-pump techniques in individuals with reduced left ventricular function.

Sleep-Disordered Breathing, Advanced Age, and Diabetes Mellitus Are Associated with De Novo Atrial Fibrillation after Cardiac Surgery.

Background: Postoperative de novo atrial fibrillation (POAF) is one of the most frequently encountered complications following cardiac surgery. Despite the identification of several risk factors, the link between sleep-disordered breathing (SDB) and POAF has barely been examined. The objective of this prospective observational study was to determine whether severe SDB is associated with POAF in patients after elective coronary artery bypass grafting (CABG) surgery. Study design and methods: The incidence and preoperative predictors of in-hospital POAF were assessed in 272 patients undergoing CABG surgery at the University Medical Center Regensburg (Germany). In-hospital POAF was detected by continuous telemetry-ECG monitoring and 12-lead resting ECGs within the first seven postoperative days. POAF that occurred after hospital discharge within 60 days post CABG surgery was classified as post-hospital POAF and was ascertained by standardized phone interviews together with the patients' medical files, including routinely performed Holter-ECG monitoring at 60 days post CABG surgery. The night before surgery, portable SDB monitoring was used to assess the presence and type of severe SDB, defined by an apnea-hypopnea index ≥ 30/h. Results: The incidence of in-hospital POAF was significantly higher in patients with severe SDB compared to those without severe SDB (30% vs. 15%, p = 0.009). Patients with severe SDB suffered significantly more often from POAF at 60 days post CABG surgery compared to patients without severe SDB (14% vs. 5%, p = 0.042). Multivariable logistic regression analysis showed that severe SDB (odds ratio, OR [95% confidence interval, CI]: 2.23 [1.08; 4.61], p = 0.030), age ≥ 65 years (2.17 [1.04; 4.53], p = 0.038), and diabetes mellitus (2.27 [1.15; 4.48], p = 0.018) were significantly associated with in-hospital POAF. After additional adjustment for heart failure, the association between sleep apnea and postoperative atrial fibrillation was attenuated (1.99 [0.92; 4.31], p = 0.081). Conclusions: Amongst established risk factors, severe SDB was significantly associated with in-hospital POAF in patients undergoing CABG surgery. Whether SDB contributes to POAF independently of heart failure and whether risk for POAF may be alleviated by proper treatment of SDB merits further investigation.