Clinical utility of CHADS2 and CHA2DS2-VASc scoring systems for predicting postoperative atrial fibrillation after cardiac surgery

Surgical Closure of the Left Atrial Appendage: The Past, The Present, The Future

Occlusion of the left atrial appendage (LAA) may protect against stroke in patients with atrial fibrillation. While percutaneous LAA closure devices have demonstrated efficacy in stroke reduction, surgical LAA occlusion has been performed with mixed results to date. Although surgical exclusion via internal sutures or noncutting stapler is ineffective due to recanalization of the LAA, surgical excision and certain exclusion devices including the AtriClip device are effective methods to achieve complete closure of the LAA. No data currently exists to support routine, prophylactic LAA closure at the time of cardiac surgery, but this practice may benefit certain patients at high risk for stroke. The currently enrolling Left Atrial Appendage Occlusion Study (LAAOS) III is the largest study to date designed to assess the efficacy of LAA occlusion for stroke prevention. The results of this trial will inform future clinical practice regarding stroke prevention with surgical LAA occlusion for patients with atrial fibrillation. Meanwhile, the ATLAS trial is investigating the efficacy of LAA occlusion in surgical patients who do not have atrial fibrillation but are at increased risk for developing it post-operatively.

Posterior Left pericardiotomy for the prevention of postoperative Atrial fibrillation after Cardiac Surgery (PALACS): study protocol for a randomized controlled trial

BACKGROUND

Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery. POAF is associated with increased morbidity and hospital costs. We herein describe the protocol for a randomized controlled trial to determine if performing a posterior left pericardiotomy prevents POAF after cardiac surgery.

METHODS/DESIGN

All patients submitted to cardiac surgery at our institution will be screened for inclusion into the study. The study will consist of two parallel arms with random allocation between groups to either receive a posterior left pericardiotomy or serve as a control. Masking will be done in a single-blinded fashion to the patient. Patients will be continuously monitored postoperatively for the occurrence of atrial fibrillation until discharge. At the follow-up clinic visit (15-30 days after surgery), the primary endpoint (atrial fibrillation) and other secondary endpoints, such as pleural or pericardial effusion, will be assessed. A total sample size of 350 subjects will be recruited.

DISCUSSION

POAF is associated with increased morbidity, prolonged hospital stay, and increased costs after cardiac surgery. Several strategies aimed at reducing the incidence of POAF have been investigated, including beta-blockers, amiodarone, and statins, all with suboptimal results. Posterior left pericardiotomy has been associated with a reduction of POAF in previous series. However, these studies had limited sample sizes and suboptimal methodology, so that the efficacy of posterior pericardiotomy in preventing POAF remains to be definitively proven. Our randomized trial aims to determine the effect of a posterior left pericardiotomy on the incidence of POAF.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02875405 , protocol record 1502015867. Registered on July 2016.

Th17/Treg Ratio in Serum Predicts Onset of Postoperative Atrial Fibrillation After Off-Pump Coronary Artery Bypass Graft Surgery

BACKGROUND

The aim of this study is to identify whether the balance between T helper 17 (Th17) cells and CD4⁺CD25⁺Foxp3⁺ regulatory T (Treg) cells could predict the postoperative atrial fibrillation (POAF) after coronary artery bypass graft surgery (CABG).

METHODS

We enrolled 88 patients from Xinhua Hospital who received off-pump CABG (OPCABG) surgery. The baseline characteristics of patients were recorded. The preoperative variables C-reactive protein (CRP) level, left atrial (LA) volume, EuroSCORE I score, CHADS₂ score, and CHA₂DS₂-VASc score were calculated at enrolment. Circulating Th17 and Treg cell frequencies were determined by flow cytometry, and expressions of Th17- and Treg-related cytokines were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared to patients without POAF, the CRP level and peripheral circulating Th17 cell were significantly increased in POAF patients. Th17/Treg ratio was positively correlated with CRP level, LA volume, CHADS₂ score, and CHA₂DS₂-VASc score. The areas under the receiver-operating characteristic (AUC) curves of Th17/Treg ratio for predicting POAF occurrence was higher than that of CRP level, LA volume, CHADS₂ score and CHA₂DS₂-VASc score. Th17/Treg ratio combined with CRP level has the highest AUC and a greater balance between sensitivity and specificity for predicting POAF.

CONCLUSIONS

Our data suggest that a Th17/Treg imbalance due to a Th17 shift, representing a pro-inflammatory tendency, participates in the development of POAF. Combining the Th17/Treg ratio with CRP level may provide a more accurate, sensitive, and specific indicator for prediction of POAF.

Cardiothoracic Critical Care

High-value CCC is rapidly evolving to meet the demands of increased patient acuity and to incorporate advances in technology. The high-performing CCC system and culture should aim to learn quickly and continuously improve. CCC demands a proactive, interactive, precise, an expert team, and continuity.

Hemodynamic parameters predict the risk of atrial fibrillation after cardiac surgery in adults

BACKGROUND

Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery and is associated with poorer prognosis. This study attempted to evaluate whether hemodynamic parameters determined by a right heart catheter predict the occurrence of POAF.

HYPOTHESIS

We hypothesized that atrial fibrillation after cardiac surgery can be predicted by hemodynamic parameters determined by a right heart catheter.

METHODS

Between October 2015 and January 2017, 126 patients with preoperative sinus rhythm undergoing coronary artery bypass grafting and/or aortic valve replacement were enrolled in this study. Complete echocardiographic examination was performed preoperatively, and hemodynamic parameters were recorded via a right heart catheter before anesthesia induction. Postoperative telemetry strips and electrocardiogram were used to detect atrial fibrillation until discharge. Multivariate logistic regression was used to identify risk factors of POAF.

RESULTS

The overall incidence of POAF was 40/126 (31.7%). Multivariate logistic regression analysis determined that left atrial dimension (LAD) (adjusted odds ratio [OR]: 1.118, 95% confidence interval [CI]: 1.020-1.227, P = 0.018), pulmonary capillary wedge pressure (PCWP) (adjusted OR: 1.225, 95% CI: 1.082-1.387, P = 0.001), and pulmonary artery systolic pressure (PASP) (adjusted OR: 1.076, 95% CI: 1.019-1.137, P = 0.008) were significant predictors of POAF.

CONCLUSIONS

The present study suggested that LAD, PCWP, and PASP were robust predictors of POAF. These parameters may indicate a patient's susceptibility toward developing POAF and help to identify patients who need preventive treatment.

CHA2DS2-VASc score and blood biomarkers to identify patients with atrial high-rate episodes and paroxysmal atrial fibrillation

AIMS

Paroxysmal atrial fibrillation (PAF) is often asymptomatic but nonetheless harmful. We evaluated the performance of disease-related blood biomarkers and CHA2DS2-VASc score to discriminate for PAF in patients with continuous rhythm monitoring.

METHODS AND RESULTS

Clinical data and blood samples were obtained from patients with dual-chamber pacemakers selected according to the absence (no_AHRE) or presence of Atrial High-Rate Episodes (AHRE) >6 min in recent device history (case-control approach). We included 93 patients (n = 49 AHRE, n = 44 no_AHRE). In a subgroup with high AHRE burden and confirmed PAF 15 biomarkers were evaluated (n = 19 AHRE-AF vs. n = 20 no_AHRE). Significantly regulated biomarkers were then tested in all patients to distinguish no_AHRE from AHRE (receiver operating characteristics analysis). Hsp27, TGFβ1, cystatin C, matrix metalloproteinases MMP-2,-3,-9, albumin, and serum uric acid were not altered in the subgroup. Tissue inhibitors of metalloproteinases (TIMP) -1,-2,-4; NT-proANP, NT-proBNP, IL-6 and serum amyloid protein A were significantly different in AHRE vs. no_AHRE (subgroup and whole cohort), with best discriminatory performance for TIMP-4. Biomarkers performed better than CHADS2-VASc for AHRE discrimination. Intracardial electrograms and medical history from seven AHRE patients suggested atrial tachycardia and not AF (AHRE-AT). Four of the most relevant regulated biomarkers (TIMP-4, TIMP-2, SAA, NT-proBNP) behaved similarly in AHRE-AT and AHRE-AF. NT-proBNP >150 pg/mL indicated an odds ratio of 12.9 for AHRE. Combining two biomarkers significantly improved discrimination of AHRE.

CONCLUSION

TIMP-4, NT-proANP, NT-proBNP were strongest associated with PAF and AHRE. The discriminatory performance of CHADS2-VASc for PAF was increased by addition of selected biomarkers.

Predictive factors of atrial fibrillation after coronary artery bypass grafting

Objective

To analyze predictive demographic and perioperative variables of postoperative atrial fibrillation in patients who underwent exclusively coronary artery bypass grafting.

Methods

This was a retrospective cohort. We randomly selected 105 medical records of patients who underwent exclusively coronary artery bypass grafting in 2014. Demographic, clinical (preoperative and immediate postoperative) data and related with surgical procedure were collected from medical records. The occurrence of postoperative atrial fibrillation was considered until the third day after the surgery. Variables were analyzed using descriptive and inferential statistics. To identify predictive factors of postoperative atrial fibrillation we used a decision tree model with Classification and Regression Trees algorithm.

Results

Atrial fibrillation incidence was 19.0% (n=20). Patients with left atrial >40.5mm and aged >64.5 years were more likely to develop the arrhythmia during the post-surgical period.

Conclusion

Left atrial diameter and advanced age were predictive factors of atrial fibrillation in patients who underwent exclusively coronary artery bypass grafting.

The impact of surgical left atrial appendage amputation/ligation on stroke prevention in patients undergoing off-pump coronary artery bypass grafting

Stroke is a major adverse event in patients developing atrial fibrillation (AF) after cardiac surgery. Surgical left atrial appendage amputation/ligation (LAA-A/L) during off-pump coronary artery bypass grafting (OPCAB) is routinely performed in our institution. We analyzed 578 consecutive patients (mean age 69 years, male 82%) undergoing OPCAB with or without concomitant LAA-A/L from 2011 to 2014 at our institution in a prospective observational manner. The safety and efficacy of the concomitant LAA-A/L on preventing early (<30 days) and overall postoperative stroke were examined. A total of 193 patients (33.4%) underwent LAA-A/L, consisting of amputation in 154 and ligation in 39 patients (80 and 20% of the cases, respectively). Preoperative characteristics, operative time, requirement of blood transfusion, and 30-day mortality were not significantly different between those with and without LAA-A/L. The incidences of postoperative AF and early and overall stroke were not significantly different between the groups in the analysis based on a total cohort. In a subanalysis of patients without LAA-A/L, early and overall stroke occurred more frequently in those developing postoperative AF than those without AF (2.8 vs. 0%; p = 0.005, 6.2 vs. 1.5%; p = 0.017, respectively), while in patients receiving LAA-A/L, stroke incidences did not differ between those with and without AF. Multivariate logistic regression showed postoperative AF without LAA-A/L as the only independent positive predictor of overall stroke (OR 3.69, p = 0.03). Concomitant LAA-A/L with OPCAB can safely prevent postoperative stroke occurrence in case patients develop AF, the most common arrhythmia associated with stroke.

Predictors of Atrial Fibrillation After Coronary Artery Bypass Grafting: A Bayesian Analysis

BACKGROUND

This study was conducted to identify preoperative predictors of postoperative atrial fibrillation (POAF) after isolated coronary artery bypass grafting (CABG) by using a Bayesian analysis that included information from prior studies.

METHODS

We performed a prospective observational study from October 2008 to December 2013 of 1,481 patients who underwent isolated CABG with cardiopulmonary bypass and had no history of AF. Bayesian analysis was used to study the preoperative risks factors for POAF.

RESULTS

The POAF incidence was 21%. Multivariate analysis identified the following independent predictors of POAF after CABG: high CHA₂DS₂-VASc (Congestive heart failure, Hypertension [blood pressure >140/90 mm Hg or treated hypertension on medication], Age ≥75 years, Diabetes mellitus, prior Stroke or transient ischemic attack or thromboembolism, vascular disease, Age 65 to 74 years, Sex category [female sex]) score (odds ratio [OR], 1.23; 95% credible interval [CI], 1.14 to 1.33 per 1-point increment, probability (Pr) [OR > 1] = 1), severe obesity with a body mass index of 35 kg/m² or higher (OR, 1.28; 95% CI, 1.12 to 1.45; Pr [OR > 1] = 1), preoperative β-blocker use (OR, 1.12; 95% CI, 1.06 to 1.20; Pr [OR > 1] = 1), preoperative antiplatelet therapy (OR, 1.75; 95% CI, 1.14 to 2.79, Pr [OR > 1] = 1), and renal insufficiency with a creatinine clearance of less than 60 mL/min (OR, 1.34; 95% CI, 1.03 to 1.74; Pr [OR > 1] = 1).

CONCLUSIONS

This prospective Bayesian analysis identified five independent preoperative predictors of POAF after isolated CABG with cardiopulmonary bypass: CHA₂DS₂-VASc score, severe obesity, preoperative β-blocker use, preoperative antiplatelet therapy, and renal failure. The main interest in the CHA₂DS₂-VASc score as a predictor of POAF is that it is a simple and widely used bedside tool. Patients with these independent predictors of POAF may constitute a target population to test preventive strategies, such as non-antiarrhythmic and antiarrhythmic drugs.

A comparison of the CHARGE-AF and the CHA2DS2-VASc risk scores for prediction of atrial fibrillation in the Framingham Heart Study

BACKGROUND

Atrial fibrillation (AF) affects more than 33 million individuals worldwide and increases risks of stroke, heart failure, and death. The CHARGE-AF risk score was developed to predict incident AF in three American cohorts and it was validated in two European cohorts. The CHA2DS2-VASc risk score was derived to predict risk of stroke, peripheral embolism, and pulmonary embolism in individuals with AF, but it has been increasingly used for AF risk prediction. We compared CHARGE-AF risk score versus CHA2DS2-VASc risk score for incident AF risk in a community-based cohort.

METHODS AND RESULTS

We studied Framingham Heart Study participants aged 46 to 94 years without prevalent AF and with complete covariates. We predicted AF risk using Fine-Gray proportional sub-distribution hazards regression. We used the Wald χ(2) statistic for model fit, C-statistic for discrimination, and Hosmer-Lemeshow (HL) χ(2) statistic for calibration. We included 9722 observations (mean age 63.9 ± 10.6 years, 56% women) from 4548 unique individuals: 752 (16.5%) developed incident AF and 793 (17.4%) died. The mean CHARGE-AF score was 12.0 ± 1.2 and the sub-distribution hazard ratio (sHR) for AF per unit increment was 2.15 (95% CI, 99-131%; P < .0001). The mean CHA2DS2-VASc score was 2.0 ± 1.5 and the sHR for AF per unit increment was 1.43 (95% CI, 37%-51%; P < .0001). The CHARGE-AF model had better fit than CHA2DS2-VASc (Wald χ(2) = 403 vs 209, both with 1 df), improved discrimination (C-statistic = 0.75, 95% CI, 0.73-0.76 vs C-statistic = 0.71, 95% CI, 0.69-0.73), and better calibration (HL χ(2) = 5.6, P = .69 vs HL χ(2) = 28.5, P < .0001).

CONCLUSION

The CHARGE-AF risk score performed better than the CHA2DS2-VASc risk score at predicting AF in a community-based cohort.

De novo atrial fibrillation post cardiac surgery: the Durban experience

Atrial fibrillation (AF) is the most common complication post cardiac surgery and results in elevated morbidity and mortality rates and healthcare costs. A pilot, retrospective study of the medical records of all adult patients developing de novo AF post surgery was undertaken at the cardiac surgical unit in Durban between 2009 and 2012. We aimed to describe the local experience of AF with a view to suggesting an adapted local treatment policy in relation to previously published data. Fifty-nine patients developed AF during the study period. AF occurred predominantly three or more days post surgery. Thirty-five patients required cardioversion and amiodarone to restore sinus rhythm. Return to the general ward (RGW) was 4.6 days longer than the institutional norm. Liberal peri-operative β-blocker and statin use is currently preferred to a formal prophylaxis strategy. Randomised, controlled trials are required to evaluate measures curbing prolonged length of stay and morbidity burdens imposed by AF on the local resource-constrained environment.

Meta-analysis of CHADS2 Score in Predicting Atrial Fibrillation

The CHADS2 score is a validated clinical tool used for the risk stratification of stroke in the presence of atrial fibrillation (AF). Recently, some studies have shown that CHADS2 score may predict the risk of AF, which yielded conflicting results. The purpose of this study is to perform a meta-analysis of observational studies to examine the association between the CHADS2 score and risk of AF. Using PubMed and EMBASE database, we searched published articles by November 2014 to identify studies that evaluated the association between CHADS2 score and the risk of AF. We used both fixed-effects and random-effects models to calculate the overall effect estimate. A sensitivity analysis and subgroup analysis were performed to find the origin of heterogeneity. Of the 1,806 studies identified initially, 19 studies were included into our analysis, with a total of 714,672 patients. The CHADS2 score was found to be an independent predictor of AF as both a continuous variable (odds ratio 1.43, 95% confidence interval 1.10 to 1.86, p = 0.007) and categorical variable (odds ratio 3.37, 95% confidence interval 2.65 to 4.28, p <0.00001). Subgroup analysis revealed that different patients' age in study population may be a possible reason for the significant heterogeneity in our meta-analysis. In conclusion, CHADS2 score predicts the risk of AF. Addressing risk factors and early recognition of AF are important and also awareness of CHADS2 score to reduce stroke risk with pharmacologic prophylaxis.

CHADS2 and CHA2DS2-VASc scoring systems for predicting atrial fibrillation following cardiac valve surgery

Objective

Clinical use of CHADS₂ and CHA₂DS₂-VASc scoring systems for predicting AF following cardiac surgery have been reported in previous studies and demonstrated well-validated predictive value. We sought to investigate whether the two scoring systems are effective for predicting new-onset of AF following cardiac valve surgery and to demonstrate its potential utility of clinical assessment.

Methods

Medical records of all patients underwent cardiac valve surgeries during the period of January 2003 and December 2013 without preoperative AF at the cardiac center of our university were reviewed. The main outcome end point of our study was the early new-onset of AF following cardiac valve surgery.

Results

There were overall 518 patients involved in this study, with 234 (45.17%) developed POAF following valve surgery. Patients with POAF had older age (P=0.23) and higher BMI (P=0.013) than those without POAF. History of heart failure (P=0.025), hypertension (P=0.021), previous stroke or TIA (P=0.032), coronary artery disease (P=0.001), carotid artery disease (P=0.024) and preoperative medication of statins (P=0.021) were significantly more recorded in POAF group. Patients with POAF also had higher LAD (P=0.013) and E/e’ ratio (P<0.001). The CHADS₂ and CHA₂DS₂-VASc scores were significantly higher in patients with POAF (P=0.002; P<0.001), and under univariate and multivariate regression analysis the CHADS₂ and CHA₂DS₂-VASc scores were significant predictors of POAF (P=0.001; P<0.001). Based on stratification of CHADS₂ and CHA₂DS₂-VASc scores, the Kaplan-Meier analysis obtained a higher POAF rate on patients with higher stratification of CHADS₂ and CHA₂DS₂-VASc scores (P<0.001; P<0.001).

Conclusion

In conclusion, CHADS₂ and CHA₂DS₂-VASc scores were directly associated with the incidence of POAF following valve surgery and a higher score was strongly predictive of POAF.

Postoperative atrial fibrillation: incidence, mechanisms, and clinical correlates

Atrial fibrillation is the most commonly encountered arrhythmia after cardiac surgery. Although usually self-limiting, it represents an important predictor of increased patient morbidity, mortality, and health care costs. Numerous studies have attempted to determine the underlying mechanisms of postoperative atrial fibrillation (POAF) with varied success. A multifactorial pathophysiology is hypothesized, with inflammation and postoperative β-adrenergic activation recognized as important contributing factors. The management of POAF is complicated by a paucity of data relating to the outcomes of different therapeutic interventions in this population. This article reviews the literature on epidemiology, mechanisms, and risk factors of POAF, with a subsequent focus on the therapeutic interventions and guidelines regarding management.

The predictive value of CHADS₂ risk score in post myocardial infarction arrhythmias - a Cardiac Arrhythmias and RIsk Stratification after Myocardial infArction (CARISMA) substudy

BACKGROUND

Previous studies have shown substantially increased risk of cardiac arrhythmias and sudden cardiac death in post-myocardial infarction (MI) patients. However it remains difficult to identify the patients who are at highest risk of arrhythmias in the post-MI setting. The purpose of this study was to investigate if CHADS₂ score (congestive heart failure, hypertension, age ≥75 years, diabetes and previous stroke/TCI [doubled]) can be used as a risk tool for predicting cardiac arrhythmias after MI.

METHODS

The study included 297 post-MI patients from the CARISMA study with left ventricular ejection fraction (LVEF) ≤40%. All patients were implanted with an implantable cardiac monitor (ICM) within 5 to 21 days post-MI and followed every three months for two years. Atrial fibrillation, bradyarrhythmias and ventricular tachycardias were diagnosed using the ICM, pacemaker or ICD. Patients were stratified according to CHADS₂ score at enrollment. Congestive heart failure was defined as LVEF ≤40% and NYHA class II, III or IV.

RESULTS

We found significantly increased risk of an arrhythmic event with increasing CHADS₂ score (CHADS₂ score=1-2: HR=2.1 [1.1-3.9], p=0.021, CHADS₂ score ≥ 3: HR=3.7 [1.9-7.1], p<0.001). This pattern was identical when dividing the arrhythmias into subgroups of atrial fibrillation, ventricular tachycardias and bradyarrhythmias. CHADS₂ score was similarly associated with the development of major cardiovascular events defined as reinfarction, stroke, and hospitalization for heart failure or cardiovascular death.

CONCLUSION

In the post-MI setting, CHADS₂ score efficiently identifies populations at high risk for cardiac arrhythmias.