Postoperative Atrial Fibrillation Following Cardiac Surgery: From Pathogenesis to Potential Therapies

Empagliflozin to prevent post-operative atrial fibrillation in patients undergoing coronary artery bypass graft surgery: Rationale and design of the EMPOAF trial

BACKGROUND

Postoperative atrial fibrillation (POAF) is one of the most common types of acute AF and can complicate the treatment course of approximately one third of patients undergoing cardiac surgery. Sodium-glucose cotransporter-2 (SGLT2) inhibitors are among the newest antidiabetic drugs which can be therapeutic options for preventing POAF by different mechanisms.

METHODS

Empagliflozin to Prevent POAF (EMPOAF) is an interventional, investigator-initiated, double-blind, placebo-controlled, multicenter, randomized controlled trial which will be conducted in two referral teaching cardiology hospitals in Tehran. Four-hundred ninety-two adult patients who are scheduled for elective isolated coronary artery bypass graft (CABG) surgery will be randomly assigned to one of the groups of intervention (empagliflozin 10 mg daily) or placebo starting at least 3 days before surgery until discharge. Key exclusion criteria are a history of diabetes mellitus, AF, ketoacidosis, or recurrent urinary tract infections along with severe renal or hepatic impairment, unstable hemodynamics, and patients receiving SGLT2 inhibitors for another indication. The primary outcome will be the incidence of POAF. Key secondary endpoints will be the composite rate of life-threatening arrhythmias, postoperative acute kidney injury, hospitalization length, in-hospital mortality, stroke, and systemic embolization. Key safety endpoints will be the rate of life-threatening and/or genitourinary tract infections, hypoglycemia, and ketoacidosis.

CONCLUSIONS

EMPOAF will prospectively evaluate whether empagliflozin 10 mg daily can reduce the rate of POAF in patients undergoing elective CABG. Enrolment into this study has started by November 2023 and is expected to be ended before the end of 2025.

Postoperative QRS duration to left ventricular end-diastolic diameter ratio as a predictor for the risk of postoperative atrial fibrillation in cardiac surgery: A single-center prospective study

Background and aims

Postoperative atrial fibrillation (POAF) is a frequent complication following cardiac surgery and is associated with adverse clinical outcomes. Our study aimed at determining the clinical and echocardiographic predictors of POAF in patients with cardiac surgery and management of this group of patients may improve their outcome.

Methods

We prospectively enrolled patients from the department of cardiovascular surgery in the Second Hospital of Tianjin Medical University from October 23, 2020 to October 30, 2022, without a history of atrial fibrillation. Cox regression was used to identify significant predictors of POAF.

Results

A total of 217 patients (79 [36.41 %] were female, 63.96 ± 12.32 years) were included. 88 (40.55 %) patients met the criteria for POAF. Cox regression showed that preoperative left atrial diameter (LAD) (HR: 1.040, 95 % CI 1.008-1.073, p = 0.013) and postoperative QRS/LVEDD (HR: 0.398, 95 % CI 0.193-0.824, p = 0.013) and E/e' (HR: 1.029, 95 % CI 1.002-1.057，p = 0.033) were predictors of POAF.

Conclusion

Preoperative LAD and postoperative QRS/LVEDD and E/e' were predictors of POAF in patients undergoing cardiac surgery.

Trial registration site

http://www.chictr.org.cn.

Registration number

ChiCTR2200063344.

Development of a Nomogram That Predicts the Risk of Atrial Fibrillation in Patients with Coronary Heart Disease

Objective

To explore the risk factors of atrial fibrillation (AF) in patients with coronary heart disease (CHD), and to construct a risk prediction model.

Methods

The participants in this case-control study were from the cardiovascular Department of Changzhou Affiliated Hospital of Nanjing University of Chinese Medicine from June 2016 to June 2023, and they were divided into AF group and non-AF group according to whether AF occurred during hospitalization. The clinical data of the two groups were compared by retrospective analysis. Multivariate Logistic regression analysis was used to investigate the risk factors of AF occurrence in CHD patients. The nomogram model was constructed with R 4.2.6 language "rms" package, and the model's differentiation, calibration and effectiveness were evaluated by drawing ROC curve, calibration curve and decision curve.

Results

A total of 1258 patients with CHD were included, and they were divided into AF group (n=92) and non-AF group (n=1166) according to whether AF was complicated. Logistic regression analysis showed that age, coronary multiple branch lesion, history of heart failure, history of drinking, pulmonary hypertension, left atrial diameter, left ventricular end-diastolic diameter and diabetes mellitus were independent risk factors for the occurrence of AF in CHD patients (P < 0.05). The ROC curve showed that the AUC of this model was 0.956 (95% CI (0.916, 0.995)) and the consistency index was 0.966. The calibration curve of the model is close to the ideal curve. The analysis of decision curve shows that the prediction value of the model is better when the probability threshold of the model is 0.042~0.963.

Conclusion

The nomogram model established in this study for predicting the risk of AF in patients with CHD has better predictive performance and has certain reference value for clinical identification of high-risk groups prone to AF in patients with CHD.

Association of CYP2C19 genotypes with postoperative atrial fibrillation after coronary artery bypass surgery

This cohort study aims to assess the connection between cytochrome P450 family 2 subfamily C member 19 (CYP2C19) genotyping, platelet aggregability following oral clopidogrel administration, and the occurrence of postoperative atrial fibrillation (POAF) after off-pump coronary artery bypass graft (CABG) surgery. From May 2017 to November 2022, a total of 258 patients undergoing elective first-time CABG surgery, receiving 100 mg/day oral aspirin and 75 mg/day oral clopidogrel postoperatively, was included for analysis. These patients were categorized based on CYP2C19 genotyping. Platelet aggregability was assessed serially using multiple-electrode aggregometry before CABG, 1 and 5 days after the procedure, and before discharge. The incidences of POAF were compared using the log-rank test for cumulative risk. CYP2C19 genotyping led to categorization into CYP2C19*1*1 (WT group, n = 123) and CYP2C19*2 or *3 (LOF group, n = 135). Baseline characteristics and operative data showed no significant differences between the two groups. The incidence of POAF after CABG was 42.2% in the LOF group, contrasting with 22.8% in the WT group (hazard risk [HR]: 2.061; 95% confidence interval [CI]: 1.347, 3.153; p = 0.0013). Adenosine diphosphate-stimulated platelet aggregation was notably higher in the LOF group compared to the WT group 5 days after CABG (30.4% ± 6.5% vs. 17.9% ± 4.1%, p < 0.001), remaining a similar higher level at hospital discharge (25.6% ± 6.1% vs. 12.2% ± 3.5%, p < 0.001). The presence of CYP2C19 LOF was linked to a higher incidence of POAF and relatively elevated platelet aggregation after CABG surgery under the same oral clopidogrel regimen.

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.

Systemic immune-inflammation index for predicting postoperative atrial fibrillation following cardiac surgery: a meta-analysis

Background

Postoperative atrial fibrillation (POAF) is a frequent complication that may increase morbidity and mortality risk following cardiac surgery. The systemic immune-inflammation index (SII) is an emerging biomarker that provides an integrated measure of inflammation by incorporating neutrophil, lymphocyte, and platelet counts. Recent studies have reported associations between elevated SII and increased POAF risk; however, significant heterogeneity exists regarding its predictive efficacy. This meta-analysis aimed to assess SII's diagnostic efficacy for predicting POAF risk.

Methods

To synthesize existing evidence on the ability of perioperative SII for predicting POAF in patients undergoing cardiac surgery, a systematic review and meta-analysis was conducted. In August 2023, a comprehensive literature search was performed to identify relevant studies reporting SII cutoff values with corresponding sensitivity and specificity. The primary aim was to evaluate SII's diagnostic utility for predicting POAF, whereas secondary outcomes included the pooled incidence of POAF and the relationship between the SII and POAF.

Results

Eight studies published between 2021 and 2023 with 3,245 patients were included. Six studies involved coronary artery bypass grafting (CABG) surgery; one encompassed various cardiac procedures, and another focused solely on mitral valve surgery. The pooled incidence of POAF was 23.6% [95% confidence interval (CI), 18.7%-29.2%]. Elevated SII significantly increased the odds of POAF by 3.24-fold (odds ratio, 3.24; 95% CI, 1.6-6.55; p = 0.001). SII's pooled sensitivity and specificity for predicting POAF were 0.80 (95% CI, 0.68-0.89) and 0.53 (95% CI, 0.23-0.8), respectively. The SII had moderate predictive accuracy based on a hierarchical summary receiver operating characteristic (HSROC) area under the curve of 0.78 (95% CI, 0.74-0.81). Subgroup analyses, whether focusing on CABG alone or CABG with cardiopulmonary bypass (CPB), both indicated an area under the HSROC curve of 0.78 (95% CI, 0.74-0.81).

Conclusion

Elevated SII is significantly correlated with an increased POAF risk following cardiac surgery, highlighting its utility as a predictive biomarker. Considering its moderate diagnostic accuracy, further research is essential for clarifying SII's clinical effectiveness, either as an independent predictor or combined with other risk factors, for stratifying patients at high POAF risk.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier [CRD42023456128].

Effect of Clinical and Genetic Factors on the Development of Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting (CABG) in Egyptian Patients Receiving Beta-Blockers

PURPOSE

Prophylactic beta-blockers are recommended to prevent postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG). Polymorphisms in the beta-1 adrenergic receptor (ADRB1) and G protein-coupled receptor kinase 5 (GRK5) genes are associated with variable responses to beta-blockers. The aim of this study was to determine the clinical and genetic factors that influence the response to beta-blockers for POAF prophylaxis after CABG.

METHODS

Patients undergoing isolated CABG and receiving prophylactic beta-blockers (n = 249) were prospectively recruited and followed up for 6 postoperative days. Genotyping of ADRB1 rs1801253, and 3 GRK5 SNPs (rs3740563, rs10787959, and rs17098707) was performed.

RESULTS

Of the 249 patients, 52 patients (20.8%) experienced POAF. Age, hypertension, vasopressor use, calculated POAF risk score, GRK5 rs2230345 T-allele, and GRK5 rs3740563 A-allele were associated with POAF despite beta-blocker prophylaxis. The multivariate analysis revealed that age [odds ratio (OR) 1.06, 95% CI 1.02-1.11, p = 0.003] and GRK5 rs2230345 T-allele [OR 2.81, 95% CI 1.39-5.67, p = 0.004] were independent predictors of POAF after CABG despite beta-blocker prophylaxis.

CONCLUSION

GRK5 rs2230345 T-allele carriers were less responsive than AA genotype carriers to prophylactic beta-blockers for the prevention of POAF after CABG. The study was registered on http://clinicaltrials.gov in March 2019, with trial registration number (TRN): NCT03871647.

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.

Investigate the relationship between obstructive sleep apnea and cardiac arrhythmia after CABG surgery

BACKGROUND AND OBJECTIVE

Heart rhythm disorder is one of the most common problems after coronary artery bypass graft surgery. Various factors, such as the history of sleep apnoea before the operation, may aggravate the occurrence of this disorder. The present study was conducted to determine the relationship between sleep apnoea before surgery and heart rhythm disorder after surgery in patients undergoing coronary Artery Bypass Grafting in 2019.

METHODS

This analytical cross-sectional study was conducted on 192 patients who were selected by sequential sampling. The research tool included demographic information, a checklist of heart rhythm disorders, and the Berlin sleep apnoea questionnaire. Descriptive statistics and the Chi-square test, Fisher's exact test, Mann-Whitney's U-test, and logistic regression were used to analyze the data.

RESULTS

A total of 71.35% of the samples were male, and the mean age of the participants was 57.8 ± 7.5 years. Also, 46.0% of the samples had sleep pane and 21.35% had rhythm disorder. The most frequent heart rhythm disorder in patients with obstructive sleep apnoea was atrial fibrillation. There was a significant relationship between the occurrence of rhythm disorder and a history of smoking (P = 0.021), and the regression model showed that a history of smoking is the only variable related to the occurrence of rhythm disorder after coronary Artery Bypass Grafting (P = 0.005, CI 95%: 6.566-1.386, OR = 3.017).

CONCLUSIONS

The results showed that there is no statistically significant relationship between sleep apnea and rhythm disorder after coronary artery bypass surgery.

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.

Machine Learning for Predicting Postoperative Atrial Fibrillation After Cardiac Surgery: A Scoping Review of Current Literature

Postoperative atrial fibrillation (POAF) occurs in up to 20% to 55% of patients who underwent cardiac surgery. Machine learning (ML) has been increasingly employed in monitoring, screening, and identifying different cardiovascular clinical conditions. It was proposed that ML may be a useful tool for predicting POAF after cardiac surgery. An electronic database search was conducted on Medline, EMBASE, Cochrane, Google Scholar, and ClinicalTrials.gov to identify primary studies that investigated the role of ML in predicting POAF after cardiac surgery. A total of 5,955 citations were subjected to title and abstract screening, and ultimately 5 studies were included. The reported incidence of POAF ranged from 21.5% to 37.1%. The studied ML models included: deep learning, decision trees, logistic regression, support vector machines, gradient boosting decision tree, gradient-boosted machine, K-nearest neighbors, neural network, and random forest models. The sensitivity of the reported ML models ranged from 0.22 to 0.91, the specificity from 0.64 to 0.84, and the area under the receiver operating characteristic curve from 0.67 to 0.94. Age, gender, left atrial diameter, glomerular filtration rate, and duration of mechanical ventilation were significant clinical risk factors for POAF. Limited evidence suggest that machine learning models may play a role in predicting atrial fibrillation after cardiac surgery because of their ability to detect different patterns of correlations and the incorporation of several demographic and clinical variables. However, the heterogeneity of the included studies and the lack of external validation are the most important limitations against the routine incorporation of these models in routine practice. Artificial intelligence, cardiac surgery, decision tree, deep learning, gradient-boosted machine, gradient boosting decision tree, k-nearest neighbors, logistic regression, machine learning, neural network, postoperative atrial fibrillation, postoperative complications, random forest, risk scores, scoping review, support vector machine.

Predictors of Developing Postoperative Atrial Fibrillation in Patients Undergoing Coronary Artery Bypass Graft: A Systematic Review and Meta-Analysis

The objective of this study was to determine predictors of postoperative atrial fibrillation (POAF) among coronary artery bypass graft (CABG) patients. This meta-analysis was conducted as per the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). Two authors performed searches independently using electronic databases, including Embase, PubMed, and Web of Science, from January 1, 2015, to November 30, 2023. A total of 16 studies were included in this meta-analysis. All included studies reported POAF in patients undergoing CABG, resulting in 1462 cases of POAF among 6200 patients undergoing CABG. The cases of POAF varied among studies, ranging from 7.80% to 47.37%. The pooled incidence of POAF was 26% (95% CI: 20% to 31%). The results indicated that older patients had a higher risk of developing atrial fibrillation (AF) after CABG (mean difference [MD]): 5.63, 95% confidence interval (CI): 4.08 to 7.17, p-value < 0.001). The findings revealed a significantly lower left ventricular ejection fraction (LVEF) in patients developing AF than their counterparts (MD: -0.30, 95% CI: -0.58 to -0.03, p-value: 0.03). Regarding the history of myocardial infarction (MI), the odds of MI were significantly higher in patients developing AF compared to those who did not develop AF (odds ratio [OR]: 1.37, 95% CI: 1.12 to 1.68, p-value: 0.002). In relation to intra-aortic balloon pump (IABP), the odds of IABP were significantly higher in patients developing AF compared to those who did not develop AF (OR: 2.27, 95% CI: 1.39 to 3.72, p-value: 0.001). Identified risk factors for post-CABG AF included advanced age, a lower preoperative ejection fraction, a history of myocardial infarction, the requirement for an IABP, and prolonged cardiopulmonary bypass (CPB) time. The study underscores the significance of proactive screening and comprehensive management for elderly CABG patients, particularly those with myocardial infarction histories.

Colchicine in atrial fibrillation: are old trees in bloom?

Colchicine is a widely used drug that was originally used to treat gout and rheumatic diseases. In recent years, colchicine has shown high potential in the cardiovascular field. Atrial fibrillation (AF) is a cardiovascular disease with a high incidence. One of the most frequent complications following cardiovascular surgery is postoperative atrial fibrillation (POAF), which affects patient health and disease burden. This article reviews the research status of colchicine in AF and summarizes the relevant progress.

Long-Term Effects of Postoperative Atrial Fibrillation following Mitral Valve Surgery

BACKGROUND

New-onset postoperative atrial fibrillation (PoAF) is one of the most frequent yet serious complications following cardiac surgery. Long-term consequences have not been thoroughly investigated, and studies have included different cardiac operations. The objectives were to report the incidence and short- and long-term outcomes in patients with PoAF after mitral valve surgery.

METHODS

This is a retrospective cohort study of 1401 patients who underwent mitral valve surgery from 2009 to 2020. Patients were grouped according to the occurrence of PoAF (n = 236) and the nonoccurrence of PoAF (n = 1165). Long-term outcomes included mortality, heart failure rehospitalization, stroke, and mitral valve reinterventions.

RESULTS

The overall incidence of PoAF was 16.8%. PoAF was associated with higher rates of operative mortality (8.9% vs. 3.3%, p < 0.001), stroke (6.9% vs. 1.5%, p < 0.001), and dialysis (13.6% vs. 3.5%, p < 0.001). ICU and hospital stays were significantly longer in patients with PoAF (p < 0.001 for both). PoAF was significantly associated with an increased risk of mortality [HR: 1.613 (95% CI: 1.048-2.483); p = 0.03], heart failure rehospitalization [HR: 2.156 (95% CI: 1.276-3.642); p = 0.004], and stroke [HR: 2.722 (95% CI: 1.321-5.607); p = 0.007]. However, PoAF was not associated with increased mitral valve reinterventions [HR: 0.938 (95% CI: 0.422-2.087); p = 0.875].

CONCLUSIONS

Atrial fibrillation after mitral valve surgery is a common complication, with an increased risk of operative mortality. PoAF was associated with lower long-term survival, increased heart failure rehospitalization, and stroke risk. Future studies are needed to evaluate strategies that can be implemented to improve the outcomes of these patients.

Predictive value of CHA2DS2VASC score for contrast-induced nephropathy after primary percutaneous coronary intervention for patients presenting with acute ST-segment elevation myocardial infarction

BACKGROUND

ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI) are at increased risk for contrast-induced nephropathy (CIN) than elective PCI procedures. Routine calculation of Mehran's score is limited by its complexity and difficulty to memorize. This study evaluated CHA₂DS₂-VASc score predictive utility for CIN in STEMI patients before pPCI.

RESULTS

Consecutive 500 acute STEMI patients presenting to two Egyptian pPCI centers were recruited. Exclusion criteria included cardiogenic shock or known severe renal impairment (baseline serum creatinine ≥ 3 mg/dL) or current or previous indication of hemodialysis. CHA₂DS₂VAS_C score_, Mehran's score, baseline estimated glomerular filtration rate (eGFR), contrast media volume (CMV) and CMV/eGFR ratio were collected for all patients. Post-pPCI CIN (defined as 0.5 mg/dL absolute increase or 25% relative increase of serum creatinine from baseline) and predictive accuracy of CHA₂DS₂VAS_C and Mehran's scores were evaluated. CIN occurred in 35 (7%) of the study group. Values of CHA₂DS₂VAS_C score_, Mehran's score, baseline eGFR, CMV and CMV/eGFR ratio were significantly higher in those who developed CIN compared to those who did not. CHA₂DS₂VAS_C score_, Mehran's score and CMV/eGFR were found to be independent predictors for CIN (P < 0.001 for all). ROC curve analysis revealed that CHA₂DS₂VAS_C ≥ 4 had a superb predictive ability, comparable to Mehran's score, for post-pPCI CIN.

CONCLUSIONS

Being practical, easily memorizable and applicable before proceeding to pPCI, routine CHA₂DS₂VAS_C score calculation in STEMI patients can effectively predict CIN risk and guide preventive and/or therapeutic interventions.

Prediction of new onset postoperative atrial fibrillation using a simple Nomogram

BACKGROUND

New onset postoperative atrial fibrillation (POAF) is the most common complication of cardiac surgery, with an incidence ranging from 15 to 50%. This study aimed to develop a new nomogram to predict POAF using preoperative and intraoperative risk factors.

METHODS

We retrospectively analyzed the data of 2108 consecutive adult patients (> 18 years old) who underwent cardiac surgery at our medical institution. The types of surgery included isolated coronary artery bypass grafting, valve surgery, combined valve and coronary artery bypass grafting (CABG), or aortic surgery. Logistic regression or machine learning methods were applied to predict POAF incidence from a subset of 123 parameters. We also developed a simple nomogram based on the strength of the results and compared its predictive ability with that of the CHA2DS2-VASc and POAF scores currently used in clinical practice.

RESULTS

POAF was observed in 414 hospitalized patients. Logistic regression provided the highest area under the receiver operating characteristic curve (ROC) in the validation cohort. A simple bedside tool comprising three variables (age, left atrial diameter, and surgery type) was established, which had a discriminative ability with a ROC of 0.726 (95% CI 0.693-0.759) and 0.727 (95% CI 0.676-0.778) in derivation and validation subsets respectively. The calibration curve of the new model was relatively well-fit (p = 0.502).

CONCLUSIONS

Logistic regression performed better than machine learning in predicting POAF. We developed a nomogram that may assist clinicians in identifying individuals who are prone to POAF.

The role of Del Nido Cardioplegia in reducing postoperative atrial fibrillation after cardiac surgery in patients with impaired cardiac function

BACKGROUND

Postoperative atrial fibrillation (POAF) occurs in 20% to 40% of patients who underwent cardiac surgery and can compromise the postoperative course, especially in those with reduced left ventricular ejection fraction. The most common causes are related to surgical trauma and the high variations in volemic and electrolyte balance in the postoperative period.

OBJECTIVES

As cardioplegic solutions can significantly impact both these factors, the study aimed to assess the role of Del Nido (DN) cardioplegia on the onset of POAF.

METHODS

A retrospective single-center analysis was carried out on 93 patients undergoing coronary artery bypass graft surgery where cardioplegia was used. The patients were divided into two groups according to the cardioplegic solution (Cold Blood vs Del Nido), and perioperative outcomes were compared.

RESULTS

POAF occurred in 21.5% of patients; the patients treated with cold blood cardioplegia (CBC) showed a 3-times higher rate of POAF compared to the DN group (OR: 3.44; 95% CI: 1.1 to 10.5; p = 0.029). The CBC group showed higher serum potassium levels both after the cross-clamp removal (p<0.001), at the ICU admission (p = 0.007), and during the first 3 postoperative days (p = 0.009). The defibrillation rate at cross-clamp removal (p = 0.003), the dose of postoperative epinephrine (p<0.001), and the peak of serum troponin (p = 0.01), were lower in the DN Group.

CONCLUSION

DN cardioplegia showed significantly reduced POAF rates after cardiac surgery by acting on the electrolyte balance, myocardial protection and on the need for postoperative inotropic support.

The occurrence of early atrial fibrillation after cardiac valve operation and the establishment of a nomogram model

Background

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery, which is associated with age and massive bleeding. However, whether thyroid hormone (TH) level can affect POAF remains controversial.

Aim

To investigate the occurrence and risk factors of POAF, in particular, the preoperative TH level of patients was introduced into this study as a variable for analysis, and a column graph prediction model of POAF was constructed.

Methods

Patients who underwent valve surgery in Fujian Cardiac Medical Center from January 2019 to May 2022 were retrospectively analyzed and divided into POAF group and NO-POAF group. Baseline characteristics and relevant clinical data were collected from the two groups of patients. Independent risk factors for POAF were screened using univariate analysis and binary logistic regression analysis, and a column line graph prediction model was established based on the regression analysis results, and the diagnostic efficacy and calibration of the model were evaluated using the Receiver Operating Characteristic Curve (ROC) and calibration curve.

Results

A total of 2,340 patients underwent valve surgery, excluding 1,751 patients, a total of 589 patients were included, including 89 patients in POAF group and 500 patients in NO-POAF group. The total incidence of POAF was 15.1%. The results of the Logistics regression analysis showed that gender, age, leukocytes and TSH were risk factors of POAF. The area under the ROC curve of the nomogram prediction model for POAF was 0.747 (95% CI: 0.688-0.806, P < 0.001), with a sensitivity of 74.2% and specificity of 68%. Hosmer-Lemeshow test showed χ ²= 11.141, P = 0.194 > 0.05, the calibration curve was well fitted.

Conclusion

The results of this study show that gender, age, leukocyte and TSH are risk factors of POAF, and the nomogram prediction model has a good prediction effect. Due to the limited sample size and included population, more studies are needed to validate this result.

Circulating Levels of Ferritin, RDW, PTLs as Predictive Biomarkers of Postoperative Atrial Fibrillation Risk after Cardiac Surgery in Extracorporeal Circulation

Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery in conventional extracorporeal circulation (CECC), with an incidence of 15-50%. The POAF pathophysiology is not known, and no blood biomarkers exist. However, an association between increased ferritin levels and increased AF risk, has been demonstrated. Based on such evidence, here, we evaluated the effectiveness of ferritin and other haematological parameters as POAF risk biomarkers in patients subjected to cardiac surgery. We enrolled 105 patients (mean age = 70.1 ± 7.1 years; 70 men and 35 females) with diverse heart pathologies and who were subjected to cardiothoracic surgery. Their blood samples were collected and used to determine hematological parameters. Electrocardiographic and echocardiographic parameters were also evaluated. The data obtained demonstrated significantly higher levels of serum ferritin, red cell distribution width (RDW), and platelets (PLTs) in POAF patients. However, the serum ferritin resulted to be the independent factor associated with the onset POAF risk. Thus, we detected the ferritin cut-off value, which, when ≥148.5 ng/mL, identifies the subjects at the highest POAF risk, and with abnormal ECG atrial parameters, such as PW indices, and altered structural heart disease variables. Serum ferritin, RDW, and PTLs represent predictive biomarkers of POAF after cardiothoracic surgery in CECC; particularly, serum ferritin combined with anormal PW indices and structural heart disease variables can represent an optimal tool for predicting not only POAF, but also the eventual stroke onset.

A novel predictive model for new-onset atrial fibrillation in patients after isolated cardiac valve surgery

Background

Postoperative atrial fibrillation (POAF) is a severe complication after cardiac surgery and is associated with an increased risk of ischemic stroke and mortality. The main aim of this study was to identify the independent predictors associated with POAF after isolated valve operation and to develop a risk prediction model.

Methods

This retrospective observational study involved patients without previous AF who underwent isolated valve surgery from November 2018 to October 2021. Patients were stratified into two groups according to the development of new-onset POAF. Baseline characteristics and perioperative data were collected from the two groups of patients. Univariate and multivariate logistic regression analyses were applied to identify independent risk factors for the occurrence of POAF, and the results of the multivariate analysis were used to create a predictive nomogram.

Results

A total of 422 patients were included in the study, of which 163 (38.6%) developed POAF. The Multivariate logistic regression analysis indicated that cardiac function (odds ratio [OR] = 2.881, 95% confidence interval [CI] = 1.595–5.206; P &lt; 0.001), Left atrial diameter index (OR = 1.071, 95%CI = 1.028–1.117; P = 0.001), Operative time (OR = 1.532, 95%CI = 1.095–2.141; P = 0.013), Neutrophil count (OR = 1.042, 95%CI = 1.006–1.08; P = 0.021) and the magnitude of fever (OR = 3.414, 95%CI = 2.454–4.751; P &lt; 0.001) were independent predictors of POAF. The above Variables were incorporated, and a nomogram was successfully constructed with a C-index of 0.810. The area under the receiver operating characteristic curve was 0.817.

Conclusion

Cardiac function, left atrial diameter index, operative time, neutrophil count, and fever were independent predictors of POAF in patients with isolated valve surgery. Establishing a nomogram model based on the above predictors helps predict the risk of POAF and may have potential clinical utility in preventive interventions.

Comprehensive characterization of the postoperative pericardial inflammatory response: Potential implications for clinical outcomes

Objective

There is a paucity of data on the inflammatory response that takes place in the pericardial space after cardiac surgery. This study provides a comprehensive assessment of the local postoperative inflammatory response.

Methods

Forty-three patients underwent cardiotomy, where native pericardial fluid was aspirated and compared with postoperative pericardial effluent collected at 4, 24, and 48 hours' postcardiopulmonary bypass. Flow cytometry was used to define the levels and proportions of specific immune cells. Samples were also probed for concentrations of inflammatory cytokines, matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs).

Results

Preoperatively, the pericardial space mainly contains macrophages and T cells. However, the postsurgical pericardial space was populated predominately by neutrophils, which constituted almost 80% of immune cells present, and peaked at 24 hours. When surgical approaches were compared, minimally invasive surgery was associated with fewer neutrophils in the pericardial space at 4 hours' postsurgery. Analysis of the intrapericardial concentrations of inflammatory mediators showed interleukin-6, MMP-9, and TIMP-1 to be highest postsurgery. Over time, MMP-9 concentrations decreased significantly, whereas TIMP-1 levels increased, resulting in a significant reduction of the ratio of MMP:TIMP after surgery, suggesting that active inflammatory processes may influence extracellular matrix remodeling.

Conclusions

These results show that cardiac surgery elicits profound alterations in the immune cell profile in the pericardial space. Defining the cellular and molecular mediators that drive pericardial-specific postoperative inflammatory processes may allow for targeted therapies to reduce immune-mediated complications.

Systemic immune-inflammation index as a novel predictor of atrial fibrillation after off-pump coronary artery bypass grafting

OBJECTIVE

This study aims to examine the predictive role of systemic immune-inflammation index on postoperative new-onset atrial fibrillation in patients undergoing off-pump coronary artery bypass grafting.

METHODS

A total of 722 patients undergoing elective off-pump coronary artery bypass grafting between January 2017 and September 2021 were included in this study and divided into two groups as the atrial fibrillation group (n=172) and the non-atrial fibrillation group (n=550). Both groups were compared in terms of patients' baseline clinical features, operative and postoperative variables, and preoperative hematological indices derived from the complete blood count analysis. Multivariate logistic regression and receiver-operating characteristic curve analyses were performed to detect the independent predictors of postoperative new-onset atrial fibrillation.

RESULTS

The median age and length of hospital stay in the atrial fibrillation group were significantly higher than those in the non-atrial fibrillation group. The median values of white blood cell, platelet, neutrophil, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, and systemic immune-inflammation in the atrial fibrillation group were significantly greater than in those in the non- atrial fibrillation group. Logistic regression analysis demonstrated that age, platelet, platelet/lymphocyte ratio, and systemic immune-inflammation were independent predictors of postoperative new-onset atrial fibrillation. receiver-operating characteristic curve analysis revealed that systemic immune-inflammation of 706.7×103/mm3 constituted cut-off value to predict the occurrence of new-onset atrial fibrillation with 86.6% sensitivity and 29.3% specificity.

CONCLUSION

Our study revealed for the first time that systemic immune-inflammation predicted new-onset atrial fibrillation after off-pump coronary artery bypass grafting.

Nomogram predicts atrial fibrillation after coronary artery bypass grafting

Objective

Using the nomogram to intuitively predict atrial fibrillation after coronary artery bypass grafting. Identify high-risk patients with atrial fibrillation and provide preoperative protective therapy.

Methods

A total of 397 patients that underwent coronary artery bypass grafting were consecutively enrolled. Independent predictors of patients were analyzed by multivariate logistic regression. Two nomograms were constructed to predict postoperative atrial fibrillation.

Results

The incidence of postoperative atrial fibrillation in this study was 29% (115/397). Multivariate Logistic showed that Age, Operative Time > 4 h, Left Atrial Diameter > 40 mm, Mean Arterial Pressure, Body Mass Index > 23 kg/m², Insulins, and Statins were independently associated with atrial fibrillation after isolated coronary artery bypass grafting. The nomogram of postoperative atrial fibrillation in patients was constructed using total predictor variables (AUC = 0.727, 95% CI 0.673–0.781). The model was internally validated (AUC = 0.701) by K-fold Cross-validation resampling (K = 5, Times = 400). To make an early intervention, the intraoperative information of the patients was excluded. Only 6 variables before surgery were used to establish the brief nomogram to predict postoperative atrial fibrillation (AUC = 0.707, 95% CI 0.651–0.764). The brief model was internally validated (AUC = 0.683) by resampling with K-fold Cross-validation resampling.

Conclusions

These two nomograms could be used to predict patients at high risk for atrial fibrillation after isolated coronary artery bypass grafting.

Pericardial Effusion Provoking Atrial Fibrillation After Cardiac Surgery: JACC Review Topic of the Week

Postoperative atrial fibrillation (POAF) is the most common complication after cardiac surgery. Patients who develop POAF are more likely to experience adverse outcomes, including increased rates of death, stroke, heart failure, and hospitalizations, and higher hospital costs. Understanding the mechanisms underlying POAF is important to improve patients' outcome and optimize health systems' efficiency. Beyond classic pathogenic hypotheses, emerging evidence suggests that postoperative pericardial effusion and localized pericardial inflammation may trigger POAF. This hypothesis is supported by data from nonhuman animal models and a growing body of evidence showing that reducing postoperative pericardial effusion might reduce POAF incidence. In this review, we summarize the classic pathophysiology theories of POAF following cardiac surgery and discuss new etiologic mechanisms with a specific focus on the role of pericardial effusion and inflammation.

[Elevation of C-reactive protein early after cardiopulmonary bypass surgery is associated with occurrence of postoperative atrial fibrillation]

OBJECTIVE

To explore the association between postoperative C-reactive protein (CRP) levels and the occurrence of postoperative atrial fibrillation in patients undergoing cardiopulmonary bypass surgery.

METHODS

We retrospectively analyzed the data of 550 patients undergoing cardiopulmonary bypass surgery in our hospital from September, 2018 to May, 2021, and after screening against the exclusion criteria, 363 patients were selected for further analysis. Univariate analysis was used to analyze the correlation of age and early postoperative CRP level with the occurrence of postoperative atrial fibrillation, and Chi-square test was used to explore the correlation of gender, disease type, and comorbidity with postoperative atrial fibrillation followed by multivariate analysis of the data using a binary logistic regression model.

RESULTS

The 363 patients enrolled in this study included 247 with valvular disease, 42 with aortic dissection, 37 with coronary heart disease, and 37 with congenital heart disease, with a median postoperative CRP level of 88.65 mg/L and a median age of 57 years (range 5-77 years). Postoperative atrial fibrillation occurred in 101 (27.82%) of the patients, who were subsequently divided into atrial fibrillation group and sinus group. Univariate and multivariate correlation analyses showed that early postoperative elevation of CRP level was an important factor contributing to the occurrence of postoperative atrial fibrillation.

CONCLUSION

Early postoperative elevation of CRP level is associated with the occurrence of atrial fibrillation following cardiopulmonary bypass surgery.

Colchicine for Prevention of Atrial Fibrillation after Cardiac Surgery in the Early Postoperative Period

Background. Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery. It has been proven to be associated with an increase in the incidence of early complications and mortality, an increase in the rate of hospital stay duration, and economic costs of their treatment. One of the pharmaceutical drugs recommended by the American College of Cardiology (ACC)/American Heart Association (AHA) for preventing POAF is colchicine (class IIB). However, the results of research on the efficacy and safety of colchicine are ambiguous and, consequently, require further study. Objective. Evaluating the efficacy of short-term colchicine administration in the prevention of POAF in patients after open-heart surgery. Materials and methods. Double-blind, randomized, placebo-controlled clinical trial. The subjects were randomly assigned to two groups: treatment group (n = 50) with subjects receiving 1 mg of colchicine 24 h before the surgery, as well as on days 2, 3, 4, and 5 in the postoperative period; and the control group (n = 51), receiving placebo on the same schedule. The primary endpoint was the frequency of POAF in both groups within 7 days after surgery. Results. The study included 101 patients (82 men, 19 women). Baseline clinical, laboratory, instrumental, and intraoperative data did not differ statistically significantly between the groups. POAF was detected in 9 patients (18%) of the treatment group and 15 subjects (29.4%) of the control group, which had no statistical significance (odds ratio, OR 0.527; 95% Cl 0.206–1.349; p = 0.178). No statistically significant differences were revealed for most secondary endpoints, as well as between the groups for all laboratory parameters. There were statistically significant differences between the groups solely in the frequency of diarrhea: 16 (32%) patients in the treatment group and 6 (11.8%) subjects in the control group (OR 3.529; 95% Cl 1.249–9.972; p = 0.010). Conclusions. We did not detect any statistical differences between the groups in terms of primary endpoints, which could be due to the insufficient volume of the sample of the study. However, we detected some trends of statistical differences among the groups in terms of some parameters. Clinical Trials Registration. ClinicalTrials. Unique identifier: NCT04224545.

Effects of dexmedetomidine on surgery for type A acute aortic dissection outcome

No study has evaluated the effect of dexmedetomidine in patients who received surgery for type A aortic dissection. This is the first study to evaluate the effect of dexmedetomidine in aortic dissection patients. This study was executed using data from the Chang Gung Research Database in Taiwan. The CGRD contains the multi‐institutional standardized electronic medical records from seven Chang Gung Memorial hospitals, the largest medical system in Taiwan. We retrospectively evaluate patients who received surgery for acute type A aortic dissection between January 2014 and December 2018. Overall, 511 patients were included, of whom 104 has received dexmedetomidine infusion in the postoperative period. One-to-two propensity score-matching yielded 86 cases in the dexmedetomidine group and 158 cases in the non-dexmedetomidine group. The in-hospital mortality and composite outcome including all-cause mortality, acute kidney injury, delirium, postoperative atrial fibrillation, and respiratory failure, were considered primary outcomes. The in-hospital mortality and composite outcome were similar between groups. The risk of Acute Kidney Injury Network stage 3 acute kidney injury was significantly lower in the dexmedetomidine group than in the non-dexmedetomidine group (8.1% vs 19.0%; OR, 0.38; 95% CI, 0.17–0.86; p = 0.020. The risk of newly-onset dialysis was also significantly lower in the dexmedetomidine group than in the non-dexmedetomidine group (4.7% vs 13.3%; OR, 0.32; 95% CI, 0.11–0.90; p = 0.031). Post-operative dexmedetomidine infusion significantly reduced the rate of severe acute kidney injury and newly-onset dialysis in patients who received surgery for acute type A aortic dissection.

Post-operative Atrial Fibrillation Impacts on Outcomes in Transcatheter and Surgical Aortic Valve Replacement

Background: Atrial fibrillation (AF) in severe aortic stenosis (AS) has poor outcomes after transcatheter and surgical aortic valve replacement (TAVR and SAVR, respectively). We compared the incidence of AF after aortic valve replacement (AVR) according to the treatment method and the impact of AF on outcomes.

Methods: We investigated the incidence of AF and clinical outcomes of AVR according to whether AF occurred after TAVR and SAVR after propensity score (PS)-matching for 1 year follow-up. Clinical outcomes were defined as death, stroke, and admission due to heart failure. The composite outcome comprised death, stroke, and admission due to heart failure.

Results: A total of 221 patients with severe AS were enrolled consecutively, 100 of whom underwent TAVR and 121 underwent SAVR. The incidence of newly detected AF was significantly higher in the SAVR group before PS-matching (6.0 vs. 40.5%, P < 0.001) and after PS-matching (7.5 vs. 35.6%, P = 0.001). TAVR and SAVR showed no significant differences in outcomes except in terms of stroke. In the TAVR group, AF history did not affect the outcomes; however, in the SAVR group, AF history affected death (log rank P = 0.038). Post-AVR AF had a worse impact on admission due to heart failure (log rank P = 0.049) and composite outcomes in the SAVR group. Post-AVR AF had a worse impact on admission due to heart failure (log rank P = 0.008) and composite outcome in the TAVR group.

Conclusion: Post-AVR AF could be considered as a predictor of the outcomes of AVR. TAVR might be a favorable treatment option for patients with severe symptomatic AS who are at high-risk for AF development or who have a history of AF because the occurrence of AF was more frequent in the SAVR group.

Influence of Dexmedetomidine on Post-operative Atrial Fibrillation After Cardiac Surgery: A Meta-Analysis of Randomized Controlled Trials

Background: Previous clinical studies and meta-analysis evaluating the influence of dexmedetomidine on postoperative atrial fibrillation showed inconsistent results. We performed an updated meta-analysis to evaluate the influence of dexmedetomidine on incidence of postoperative atrial fibrillation after cardiac surgery.

Methods: Randomized controlled trials that evaluated the potential influence of dexmedetomidine on the incidence of atrial fibrillation after cardiac surgery were obtained by search of PubMed, Embase, and Cochrane's Library databases from inception to April 12, 2021. A random-effects model incorporating the potential publication bias was used to pool the results. Influences of patient or study characteristics on the efficacy of dexmedetomidine on atrial fibrillation after cardiac surgery were evaluated by meta-regression and subgroup analyses.

Results: Fifteen studies with 2,733 patients were included. Pooled results showed that dexmedetomidine significantly reduced the incidence of atrial fibrillation compared to control (OR: 0.72, 95% CI: 0.55–0.94, p = 0.02) with mild heterogeneity (I² = 26%). Subgroup analysis showed that dexmedetomidine significantly reduced the incidence of atrial fibrillation in studies from Asian countries (OR: 0.41, 95% CI: 0.26–0.66, p < 0.001), but not in those from non-Asian countries (OR: 0.89, 95% CI: 0.71–1.10, p = 0.27; p for subgroup difference = 0.004). Meta-regression analysis showed that the mean age and proportion of male patients may modify the influence of dexmedetomidine on POAF (coefficient = 0.028 and 0.021, respectively, both p < 0.05). Subgroup analysis further showed that Dex was associated with reduced risk of atrial fibrillation after cardiac surgery in studies with younger patients (mean age ≤ 61 years, OR = 0.44, 95% CI: 0.28–0.69, p = 0.004) and smaller proportion of males (≤74%, OR = 0.55, 95% CI: 0.36–0.83, p = 0.005), but not in studies with older patients or larger proportion of males (p for subgroup difference = 0.02 and 0.04).

Conclusions: Current evidence supports that perioperative administration of dexmedetomidine may reduce the risk of incidental atrial fibrillation after cardiac surgery, particularly in Asians.

Research Progress on Molecular Markers Related to Unexplained Sudden Cardiac Death and Its Forensic Application

Routine pathological examination of unexplained sudden cardiac death (USCD) lacks significant morphological characteristics. In the field of forensic medicine, molecular biology methods have been used to find the cause of death by detecting genes and research related to the mechanism of sudden cardiac death has been carried out. From the molecular pathology point of view, the application of multiple levels of biomarkers to resolve the causes of USCD has already shown potential and provides an important path for forensic identification of USCD. This article reviews the latest research progress on USCD-related genes, RNA, proteins and USCD, and summarizes forensic application.

Early Thromboembolic Stroke Risk of Postoperative Atrial Fibrillation Following Cardiac Surgery

OBJECTIVE

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

DESIGN

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

PARTICIPANTS

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

SETTING

Academic tertiary care medical center.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

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

CONCLUSIONS

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

Optimising risk factors for atrial fibrillation post-cardiac surgery

Postoperative atrial fibrillation (POAF) is an ongoing complication following cardiac surgery, with an incidence of 15%-60%. It is associated with substantial mortality and morbidity, as well increased hospital stays and healthcare costs. The pathogenesis is not fully understood, but the literature suggests that POAF occurs when transient, postoperative triggers act on vulnerable atrial tissue produced by preoperative, procedure-induced and postoperative processes such as inflammation, oxidative stress, autonomic dysfunction and electrophysiological remodelling of the atrial tissues. This sets the stage for arrhythmogenic mechanisms, such as ectopic firing secondary to triggered activity and re-entry mechanisms generating POAF. Preoperative factors include advanced age, sex, ethnicity, cardiovascular risk factors, preoperative drugs, electrocardiogram and echocardiogram abnormalities. Procedural factors include: the use of cardiopulmonary bypass and aortic cross clamp, type of cardiac surgery, use of hypothermia, left ventricular venting, bicaval cannulation and exclusion of the left atrial appendage. Postoperative factors include postoperative drugs, electrolyte and fluid balance and infection. This review explores the pathogenesis of POAF and the contribution of these perioperative factors in the development of POAF. Patients can be risk stratified for targeted treatment and prophylaxis, and how these factors can be attenuated to improve POAF outcomes following cardiac surgery.

Local Use of Hydrogel with Amiodarone in Cardiac Surgery: Experiment and Translation to the Clinic

The objective of this study was to study the use of the hydrogel biopolymer based on sodium alginate ("Colegel") with a drug substance-amiodarone-for the prevention of postoperative atrial fibrillation (POAF) in cardiac surgery. The experimental part of the study was performed on 46 rabbits. Five groups were formed: in the first group, the dose of amiodarone in hydrogel was 1 mg; in the second group-3 mg; in the third group-6 mg; in the fourth group, hydrogel was used without amiodarone; in the fifth group, 60 mg amiodarone was administered intravenously. The animals from each group were removed from the experiment for the pathomorphological study of the heart after 3, 7 and 14 days. The studied endpoints were: the heart rate control; the development of the blockades of the conduction system of the heart; and the development of inflammation according to laboratory pathomorphological studies. The translational clinical part involved a randomized clinical trial which included 60 patients, with an average age of 62 ± 8.5 years. All patients were randomized into two groups: the study group (n = 30, with the application of amiodarone hydrogel) and the control group (n = 30, without the application of amiodarone hydrogel). The dose of amiodarone in the hydrogel material was 60 mg for all patients. The heart rhythm was monitored during 5 days. The primary endpoint was the development of POAF. Secondary endpoints were: the dynamics of heart rate; the duration of the QT and PQ intervals; the development of blockades of the cardiac conduction system; as well as the dynamics of AST and ALT. According to the results of the experimental part, it was found that the method of the local epicardial delivery of amiodarone by the hydrogel material was safe. Hydrogel with amiodarone is effective for reducing the heart rate in the animal experiment in comparison to the control group and the group with the intravenous administration of the drug. The optimal dose of amiodarone in hydrogel was 1 mg per 1 kg. According to the results of the clinical part, it was found that the method of the local epicardial delivery of amiodarone as a hydrogel material proved its safety. Hydrogel with amiodarone at a dose of 60 mg was effective in preventing POAF in patients after coronary artery bypass grafting (CABG) operations in comparison to the control group (p < 0.001). The age and procedure of application of the amiodarone gel were significantly associated with POAF (p = 0.009 and p = 0.011, respectively). The use of hydrogel with amiodarone reduced the probability of developing POAF 18.9-fold. The method of the local epicardial delivery of amiodarone in the form of a hydrogel material is safe. The use of hydrogel with amiodarone after CABG reduced the probability of developing POAF.

The preoperative glomerular filtration rate predicts new-onset postoperative atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy who undergo isolated septal myectomy

Background

Few studies have focused on new-onset postoperative atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy who have undergone septal myectomy. Therefore, we investigated the incidence and prognosis effects of postoperative atrial fibrillation following septal myectomy in patients with hypertensive obstructive cardiomyopathy. Additionally, we investigated the relationship of estimated glomerular filtration rate and postoperative atrial fibrillation.

Methods

Data from 300 patients with hypertrophic obstructive cardiomyopathy who underwent isolated surgical septal myectomy were collected from January 2012 to March 2018.

Results

The overall incidence of postoperative atrial fibrillation during hospitalization was 22.67% (68 of 300 patients). Patients with postoperative atrial fibrillation were older (P<0.001), had lower preoperative estimated glomerular filtration rate (P<0.001), and a larger preoperative left atrial diameter (P=0.038) compared to patients without. The preoperative estimated glomerular filtration rate predicted postoperative atrial fibrillation with sensitivity and specificity of 0.824 and 0.578 (P<0.001), respectively. Multivariate regression analyses showed that age [odds ratio (OR) =1.090, 95% confidence interval (CI): 1.034-1.110], an New York Heart Association functional class ≥ III (OR =2.985, 95% CI: 1.349-6.604), hypertension (OR =2.212, 95% CI: 1.062-4.608), a history of syncope (OR =3.890, 95% CI: 1.741-8.692), and the preoperative estimated glomerular filtration rate (OR =0.981, 95% CI: 0.965-0.996) were independent risk factors associated in the development of postoperative atrial fibrillation. Survival analysis showed that the incidence of long-term cardiovascular events was higher in the patients with postoperative atrial fibrillation than that in the patients without the condition (P<0.001).

Conclusions

The preoperative estimated glomerular filtration rate was a moderate predictor of postoperative atrial fibrillation after septal myectomy. Postoperative atrial fibrillation affected the early recovery and the long-term prognoses of patients with hypertrophic obstructive cardiomyopathy who underwent septal myectomy.

Management of Atrial Fibrillation Following Cardiac Surgery: Observational Study and Development of a Standardized Protocol

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common complication occurring after cardiac surgery. Guidelines for the management of this complication are scarce, often resulting in differences in treatment strategy use among patients.

OBJECTIVE

To evaluate the management of POAF in a cardiac surgery department, characterize the extent of its variability, and develop a standardized protocol.

METHODS

This was an observational retrospective study with data from patients who underwent cardiac surgeries with subsequent POAF between January 1, 2017, and June 1, 2018. We assessed the difference in the proportions of patients whose first POAF episodes were treated with a rate control (RaC) strategy, a rhythm control (RhC) strategy, and both among different hospital units. We also assessed the mean duration of POAF episodes, POAF recurrences, and the management of anticoagulation.

RESULTS

Data from 97 patients were included in this study. The POAF management strategy differed significantly among the 3 types of hospital units (P = 0.001). Considering all POAF episodes (including all recurrences), 83 of the 97 patients (85.6%) received amiodarone as part of the RhC strategy. Anticoagulation was used in 58 (59.8%) patients and was suboptimal according to the study criteria in 29.5% of the patients included. Based on these results, a hospital working group developed a standardized protocol for POAF management.

CONCLUSIONS AND RELEVANCE

POAF management was heterogeneous at our institution. This article highlights the need for clear practice guidelines based on large prospective studies to provide care according to best practices.

The C-reactive protein/albumin ratio as a new predictor for postoperative atrial fibrillation after coronary artery bypass graft surgery

BACKGROUND

This study aimed to investigate the predictive significance of C-reactive protein/albumin ratio for postoperative atrial fibrillation occurrence in patients who were underwent coronary artery bypass graft surgery.

METHODS

Among 830 patients who underwent coronary artery bypass grafting with cardiopulmonary bypass between January 2016 and February 2020, 137 patients with no prior arrhythmia history were included in this cross sectional study.

RESULTS

One hundred and thirty-seven (16.5%) patients developed atrial fibrillation in postoperative period. Patients who experienced postoperative atrial fibrillation were more likely to be older but displayed similar rates of diabetes mellitus, hypertension, hypercholesterolemia, cerebrovascular disease, peripheral vascular disease and chronic obstructive pulmonary disease. For prediction of postoperative atrial fibrillation development, diagnostic odds ratio (OR) and positive likelihood ratio of C-reactive protein/albumin ratio value (OR: 1.854; confidence interval [CI]: 1.598-2.142; P < .001) was higher than serum C-reactive protein and albumin levels. (OR: 1.159; CI: 1.115-1.201; P < .001; OR: 0.438; CI: 0.258-0.865; P < .001, respectively). Which means that C-reactive protein/albumin ratio may detect postoperative atrial fibrillation development better C-reactive protein itself.

CONCLUSION

Based on our results, patients who developed postoperative atrial fibrillation after coronary artery bypass grafting had significantly higher preoperative C-reactive protein/albumin ratio levels than patients who remained in normal sinus rhythm in the postoperative period. Also, higher C-reactive protein/albumin ratio value was one of the independent predictive factors for postoperative atrial fibrillation. Therefore, we concluded that evaluating preoperative C-reactive protein/albumin ratio value might provide early identification of patients with high risk for postoperative atrial fibrillation.

Dexmedetomidine for reduction of atrial fibrillation and delirium after cardiac surgery (DECADE): a randomised placebo-controlled trial

BACKGROUND

Atrial fibrillation and delirium are common consequences of cardiac surgery. Dexmedetomidine has unique properties as sedative agent and might reduce the risk of each complication. This study coprimarily aimed to establish whether dexmedetomidine reduces the incidence of new-onset atrial fibrillation and the incidence of delirium.

METHODS

A randomised, placebo-controlled trial was done at six academic hospitals in the USA. Patients who had had cardiac surgery with cardiopulmonary bypass were enrolled. Patients were randomly assigned 1:1, stratified by site, to dexmedetomidine or normal saline placebo. Randomisation was computer generated with random permuted block size 2 and 4, and allocation was concealed by a web-based system. Patients, caregivers, and evaluators were all masked to treatment. The study drug was prepared by the pharmacy or an otherwise uninvolved research associate so that investigators and clinicians were fully masked to allocation. Participants were given either dexmedetomidine infusion or saline placebo started before the surgical incision at a rate of 0·1 μg/kg per h then increased to 0·2 μg/kg per h at the end of bypass, and postoperatively increased to 0·4 μg/kg per h, which was maintained until 24 h. The coprimary outcomes were atrial fibrillation and delirium occurring between intensive care unit admission and the earlier of postoperative day 5 or hospital discharge. All analyses were intention-to-treat. The trial is registered with ClinicalTrials.gov, NCT02004613 and is closed.

FINDINGS

798 patients of 3357 screened were enrolled from April 17, 2013, to Dec 6, 2018. The trial was stopped per protocol after the last designated interim analysis. Among 798 patients randomly assigned, 794 were analysed, with 400 assigned to dexmedetomidine and 398 assigned to placebo. The incidence of atrial fibrillation was 121 (30%) in 397 patients given dexmedetomidine and 134 (34%) in 395 patients given placebo, a difference that was not significant: relative risk 0·90 (97·8% CI 0·72, 1·15; p=0·34). The incidence of delirium was non-significantly increased from 12% in patients given placebo to 17% in those given dexmedetomidine: 1·48 (97·8% CI 0·99-2·23). Safety outcomes were clinically important bradycardia (requiring treatment) and hypotension, myocardial infarction, stroke, surgical site infection, pulmonary embolism, deep venous thrombosis, and death. 21 (5%) of 394 patients given dexmedetomidine and 8 (2%) of 396 patients given placebo, had a serious adverse event as determined by clinicians. 1 (<1%) of 391 patients given dexmedetomidine and 1 (<1%) of 387 patients given placebo died.

INTERPRETATION

Dexmedetomidine infusion, initiated at anaesthetic induction and continued for 24 h, did not decrease postoperative atrial arrhythmias or delirium in patients recovering from cardiac surgery. Dexmedetomidine should not be infused to reduce atrial fibrillation or delirium in patients having cardiac surgery.

FUNDING

Hospira Pharmaceuticals.