Role of CHADS2 score in evaluation of thromboembolic risk and mortality in patients with atrial fibrillation undergoing direct current cardioversion (from the ACUTE Trial Substudy)

Transesophageal Echocardiogram Before Cardioversion in Atrial Fibrillation Patients

Transesophageal echocardiography (TEE) offers an invaluable, non-invasive avenue for diagnosing and managing various cardiac conditions, including atrial fibrillation (AF). As the most common cardiac arrhythmia, AF affects millions and can lead to severe complications. Cardioversion, a procedure to restore the heart's normal rhythm, is frequently conducted on AF patients resistant to medication. Due to inconclusive data, TEE's utility prior to cardioversion in AF patients remains ambiguous. Understanding TEE's potential benefits and limitations in this population could significantly influence clinical practice. This review aims to scrutinize the current literature on the use of TEE before cardioversion in AF patients. The principal objective is to understand TEE's potential benefits and limitations comprehensively. The study seeks to offer a clear understanding and practical recommendations for clinical practice, thereby improving the management of AF patients before cardioversion using TEE. A literature search of databases was conducted using the keywords "Atrial Fibrillation," "Cardioversion" and "Transesophageal echocardiography," resulting in 640 articles. These were narrowed to 103 following title and abstract reviews. After applying exclusion and inclusion criteria with a quality assessment, 20 papers were included: seven retrospective studies, 12 prospective observational studies, and one randomized controlled trial (RCT). Stroke risk associated with direct-current cardioversion (DCC) potentially results from post-cardioversion atrial stunning. Thromboembolic events occur post cardioversion, with or without prior atrial thrombus or cardioversion complications. Generally, cardiac thrombus localizes in the left atrial appendage (LAA), a clear contraindication to cardioversion. Atrial sludge without LAA thrombus in TEE is a relative contraindication. TEE before electrical cardioversion (ECV) in anticoagulated AF individuals is uncommon. In AF patients planned for cardioversion, contrast enhancement facilitates thrombus exclusion in TEE images, reducing embolic events. Left atrial thrombus (LAT) frequently occurs in AF patients, necessitating TEE examination. Despite the increased use of pre-cardioversion TEE, thromboembolic events persist. Notably, patients with post-DCC thromboembolic events had no LA thrombus or LAA sludge. The use of TEE-guided DCC has grown due to its ability to detect atrial thrombi pre-cardioversion, aiding risk stratification. Thrombus in the left atrium also signals an elevated risk of future thromboembolic events in AF patients. While atrial stunning post cardioversion detected by TEE is a significant risk factor for future thromboembolic events, further evidence is required. Therapeutic anticoagulation is essential during and post cardioversion, even if no atrial thrombus is detected. Current data recommends cardioversion guided by TEE, particularly in outpatient settings.

The Association between Influenza Vaccination and Stroke Risk in Patients with Hypertension: A Nationwide Population-Based Study

There is evidence of strong association between influenza infections and stroke; however, the influenza vaccination and its effect on strokes is currently unclear. In the present study, Taiwan’s National Health Insurance Database was used in obtaining data for study subjects 55 years and older diagnosed with hypertension (n = 59,251; 25,266 vaccinated and 33,985 unvaccinated subjects) from 2001–2012. Propensity scores were calculated using a logistic regression model to determine the effects of vaccination by accounting for covariates that predict receiving the intervention (vaccine). A time-dependent Cox proportional hazard model was used to calculate the hazard ratios (HRs) for stroke in vaccinated and unvaccinated patients. Influenza vaccination was associated with a 42%, 40% and 44% stroke risk reduction in the entire cohort for all seasons, the influenza season and the non-influenza season, respectively (Adjust hazard ratio [aHR]: 0.58, 95% confidence interval [CI]: 0.56–0.61; aHR: 0.60, 95% CI: 0.56–0.63; aHR: 0.56, 95% CI: 0.52–0.60, for all seasons, the influenza season and the non-influenza season, respectively). The effect of risk reduction by vaccination also revealed a trend of dose dependency. Among subjects between 55 to 64 years old with four or more vaccinations during the study period, there is a 73% risk reduction for stroke during the non-influenza season (aHR: 0.27, 95% CI: 0.20–0.34). In conclusion, the influenza vaccination exerts dose-dependent and synergistic protective effects against stroke in individuals 55 years and older with hypertension.

Impact of thyroid disease in patients with atrial fibrillation: Analysis from the JoFib registry

Background

Thyroid disease is a well-established risk factor for atrial fibrillation (AF). However, only a handful of studies examined its impact on treatment. This study aims to report the prevalence rate of thyroid disease in patients with AF and to demonstrate the effect of thyroid disease on AF treatment.

Materials and methods

We retrospectively analyzed the Jordanian Atrial Fibrillation Study (JoFib). Among Jordan and Palestine, patients with AF were evaluated for their sociodemographic, clinical, and pharmacological characteristics.

Results

A total of 2000 patients with AF (53.3% males, mean age 67.6 ± 13.1 years) were enrolled in the JoFib registry from May 2019 to November 2020. Thyroid disease was present in 210 (10.5%) patients. Hypertension, diabetes mellitus, and dyslipidemia were the most common comorbidities among patients with thyroid history (75.2%, 51.0%, and 45.7%, respectively). Diabetes mellitus (p = .04), pulmonary hypertension (p = .01), and chronic kidney disease (p = .01) were significantly higher in this particular subgroup. Patients with thyroid disease demonstrated significantly higher usage of anticoagulants (p = .02).

Conclusion

Despite having similar stroke and bleeding risks, patients with thyroid disease demonstrated meaningful differences in their baseline characteristics. Prospective studies are required to assess the influence of thyroid hormone fluctuations on the progression of AF.

•

Thyroid disease doesn't appear to impact bleeding risk in atrial fibrillation.

•

Patients with thyroid disease are more likely to consume more anticoagulants.

•

Thyroid disease in atrial fibrillation maybe linked with pulmonary hypertension.

•

Assessment tools of stork or bleeding may be underestimated in Arab Jordanians.

Nomogram to Predict Left Atrial Thrombus or Spontaneous Echo Contrast in Patients With Non-valvular Atrial Fibrillation

Background: The predictive power of the CHADS₂ and CHA₂DS₂-VASc scores for the presence of Left atrial thrombus (LAT)/ spontaneous echo contrast (SEC) in non-valvular atrial fibrillation (NVAF) is modest. The aim of this analysis is to define clinical and ultrasonic variables associated with LAT/SEC and to propose nomograms for individual risk prediction.

Methods: Data on 1,813 consecutive NVAF patients who underwent transesophageal echocardiography (TEE) from January 2016 to January 2021 were collected. The univariate and multivariate logistic regression analyses were used to construct a nomogram. We examined the predictive ability of the risk scores by calculating the area under the curve (AUC). Moreover, the performance of the nomogram was assessed with respect to calibration, discrimination, and clinical usefulness.

Results: LAT/SEC was found in 260 (21.0%) and 124 (21.6%) patients in the training and validation cohorts, respectively. On multivariate analysis, independent factors for LAT/SEC were Age, left atrial diameter (LAD), left ventricular ejection fraction (LVEF), hypertension (HTN), previous stroke or transient ischemic attack, Non-paroxysmal AF and a nomogram was built based on these variables. The calibration curve for the probability of LAT/SEC showed good prediction agreement with actual observation. The nomogram achieved good concordance indexes of 0.836 and 0.794 in predicting LAT/SEC in the training and validation cohorts, respectively. Decision curve analysis demonstrated that the nomogram would be clinically useful.

Conclusions: In this study, a nomogram was constructed that incorporated six characteristics of NVAF patients. The nomogram may be of great value for the prediction of LAT/SEC in NVAF patients.

Determinants of left atrial thrombus or spontaneous echo contrast in nonvalvular atrial fibrillation

BACKGROUND

The CHADS₂ and CHA₂DS₂-VASc scores are well-established clinical scales to estimate the risk of stroke in patients with atrial fibrillation (AF). However, the predictive power of the two scales concerning left atrial thrombus (LAT) or spontaneous echo contrast (SEC) has not been well investigated. Therefore, we investigated the predict power of CHADS₂ and CHA₂DS₂-VASc scores concerning LAT/SEC; identified clinical, echocardiographic and laboratory predictors of LAT/SEC in addition to the CHADS₂ and CHA₂DS₂-VASc scores; and derived a new scale to predict LAT/SEC accurately, it might improve thromboembolic risk stratification in patients with nonvalvular atrial fibrillation.

METHODS

We identified 1102 consecutive AF patients who underwent transesophageal echocardiography (TEE) for the purpose of the exclusion of LAT before catheter ablation, cardioversion or left atrial appendage occlusion. The clinical, echocardiographic and laboratory characteristics of patients were collected from the electronic medical record system.

RESULTS

In the study, the prevalence of LAT/SEC was only 4.36%. In the multivariate logistic analysis, hypertension, left atrial enlargement, prior stroke/TIA, left ventricular dysfunction, and renal dysfunction were predictors of LAT/SEC. Receiver operating characteristic curve analysis showed that c-statistics of the CHADS₂ and CHA₂DS₂-VASc scores concerning LAT/SEC were 0.673 and 0.643, respectively. We derived a new scale composed of variables from the multivariate logistic analysis that showed a higher c-statistic value (0.761) than the CHADS₂ and CHA₂DS₂-VASc scores for the prediction of LAT/SEC.

CONCLUSION

In our cohort, we found two variables not included in the CHA₂DS₂-VASc score (renal dysfunction, left atrial enlargement) were independent predictors of LAT/SEC. A new scale combining clinical, echocardiographic and laboratory predictors might improve thromboembolic risk stratification. And there is a great need to carry out a new prospective and multicenter study, with a population more homogenous and including all the determinants for LAT/SEC to establish the independent degree of each variable and the applicability in clinical practice, facilitating the emergence of a new score of thromboembolic risk in patients with nonvalvular atrial fibrillation.

Left Atrial Strain as Evaluated by Two-Dimensional Speckle Tracking Predicts Left Atrial Appendage Dysfunction in Chinese Patients with Atrial Fibrillation

Left atrial appendage (LAA) dysfunction identified by transesophageal echocardiography (TEE) is a powerful predictor of stroke in patients with atrial fibrillation (AF). The aim of our study is to assess if there is a correlation between the left atrial (LA) functional parameter and LAA dysfunction in the AF patients. This cross-sectional study included a total of 249 Chinese AF patients who did not have cardiac valvular diseases and were undergoing cardiac ablation. TEE was performed in all the patients who were categorized into two groups according to their left atrial appendage (LAA) function. A total of 120 of the 249 AF patients had LAA dysfunction. Univariate and multivariate logistic regression was conducted to assess the independent factors that correlated with the LAA dysfunction. Different predictive models for the LAA dysfunction were compared with the receiver operating characteristic (ROC) curve. The final ROC curve on the development and validation datasets was drawn based on the calculation of each area under the curves (AUC). Univariate and multivariate analysis showed that the peak left atrial strain (PLAS) was the most significant factor that correlated with the LAA dysfunction. PLAS did not show inferiority amongst all the models and revealed strong discrimination ability on both the development and validation datasets with AUC 0.818 and 0.817. Our study showed that a decrease in PLAS is independently associated with LAA dysfunction in the AF patients.

Improving the quality of care for patients with or at risk of atrial fibrillation: an improvement initiative in UK general practices

Objective

Atrial fibrillation (AF) is a growing problem internationally and a recognised cause of cardiovascular morbidity and mortality. The London borough of Hounslow has a lower than expected prevalence of AF, suggesting poor detection and associated undertreatment. To improve AF diagnosis and management, a quality improvement (QI) initiative was set up in 48 general practices in Hounslow. We aimed to study whether there was evidence of a change in AF diagnosis and management in Hounslow following implementation of interventions in this QI initiative.

Methods

Using the general practice information system (SystmOne), data were retrospectively collected for 415 626 patients, who were actively registered at a Hounslow practice between 1 January 2011 and 31 August 2018. Process, outcome and balancing measures were analysed using statistical process control and interrupted time series regression methods. The baseline period was from 1 January 2011 to 30 September 2014 and the intervention period was from 1 October 2014 to 31 August 2018.

Results

When comparing the baseline to the intervention period, (1) the rate of new AF diagnoses increased by 27% (relative risk 1.27; 95% CI 1.05 to 1.52; p<0.01); (2) ECG tests done for patients aged 60 and above increased; (3) CHA₂DS₂-VASc and HAS-BLED risk assessments within 30 days of AF diagnosis increased from 1.7% to 19% and 0.2% to 8.1%, respectively; (4) among those at higher risk of stroke, anticoagulation prescription within 30 days of AF diagnosis increased from 31% to 63% while prescription of antiplatelet monotherapy within the same time period decreased from 17% to 7.1%; and (5) average CHA₂DS₂-VASc and HAS-BLED risk scores did not change.

Conclusion

Implementation of interventions in the Hounslow QI initiative coincided with improved AF diagnosis and management. Areas with perceived underdetection of AF should consider similar interventions and methodology.

Diagnosis and Management of Left Atrium Appendage Thrombosis in Atrial Fibrillation Patients Undergoing Cardioversion

Atrial fibrillation is the most common cardiac arrhythmia and is associated with an increased risk of stroke and thromboembolic complications. A rhythm control strategy with both electrical and pharmacological cardioversion is recommended for patients with symptomatic atrial fibrillation. Anticoagulant therapy for 3–4 weeks prior to cardioversion is recommended in order to avoid thromboembolic events deriving from restoring sinus rhythm. Transesophageal echocardiography has a pivotal role in this setting, excluding the presence of left atrial appendage thrombus before cardioversion. The aim of this review is to discuss the epidemiology and risk factors for left atrial appendage thrombosis, the role of echocardiography in the decision making before cardioversion, and the efficacy of different anticoagulant regimens on the detection and treatment of left atrial appendage thrombosis.

Stroke Risk in Atrial Fibrillation: Beyond the CHA2DS2-VASc Score

PURPOSE OF REVIEW

Stroke prevention is the cornerstone of atrial fibrillation (AF) management and the anticoagulation decision is currently based on CHA₂DS₂-VASc risk score. We discuss several novel risk factors besides those included in CHA₂DS₂-VASc score and alternative models for stroke prediction.

RECENT FINDINGS

Several clinical markers including obstructive sleep apnea and renal failure, laboratory markers like brain natriuretic peptide, imaging criteria including left atrial appendage morphology, spontaneous echo contrast, and coronary artery calcium score may predict stroke in AF patients. Addition of African American ethnicity to CHA₂DS₂-VASc score also improves stroke prediction in AF. Finally, novel models including TIMI-AF score, ATRIA score, and GARFIELD-AF scores have potential roles in risk stratification for stroke. While CHA₂DS₂-VASc score is the currently recommended risk stratification model for stroke prediction in AF, use of additional clinical, laboratory, imaging markers, ethnicity, and novel stroke prediction models may further assist in decision to anticoagulate the AF patient for stroke prevention.

Real-time surveillance of left atrial appendage thrombus during contrast computed tomography imaging for catheter ablation: THe Reliability of cOMputed tomography Beyond UltraSound in THROMBUS detection (THROMBUS) study

Left atrial contrast computed tomography (LA-CT) as well as transesophageal echocardiography (TEE) can exclude left atrial appendage (LAA) thrombus, but is sometimes unable to evaluate LAA due to incomplete LAA filling. The aim of the current study was to validate the utility of real-time approach of LA-CT with real-time surveillance of LAA-filling defect (FD). We enrolled consecutive 894 patients with LA-CT studies acquired for catheter ablation and compared the diagnostic accuracy in demonstrating LAA-FD between conventional protocol (N = 474) and novel protocol with real-time surveillance of LAA-FD immediately after the initial scanning and, when necessary, adding delayed scanning in the supine or prone position (N = 420). Primary endpoint was severity of LAA-FD classified into the 3 groups: "Grade-0" for complete filling of contrast, "Grade-1" for incomplete filling of contrast, and "Grade-2" for complete FD of contrast. The prevalence of Grade-1 and Grade-2 FD was 17.3% and 11.2% in conventional protocol, whereas there was no patient with Grade-2 FD, and only 1 patient with Grade-1 FD after the additional scanning in novel protocol. In 5 patients with suspected LAA thrombus both by TEE and Grade-2 FD in LA-CT by the conventional protocol, ablation procedure was canceled due to diagnosis of LAA thrombus. Conversely, 4 patients with suspected LAA thrombus by TEE in novel protocol group was proved to have intact LAA by LA-CT with and without additional scanning. This novel approach with real-time surveillance improved the diagnostic accuracy of LA-CT in detecting LAA-FD, suggesting potential superiority of LA-CT over TEE in excluding LAA thrombus.

Direct Oral Anticoagulants in Patients Undergoing Spine Surgery

OBJECTIVE

Despite increasing use of direct oral anticoagulants (DOACs), guidelines for their perioperative use in spine surgery are still lacking. The main goal of our study was to analyze the occurrence of postoperative bleeding events and possible confounders in patients treated with DOACs who undergo spine surgery.

METHODS

Of 2777 patients undergoing spine surgery at our institution, 82 (2.9%) were treated with DOACs. The primary endpoint was postoperative bleeding events. Secondary outcome measures were postoperative thromboembolic events and anemia, hematologic findings, perioperative packed red blood cell substitution, operative time, hospital length of stay, morbidity, and mortality. Subanalysis of possible confounders affecting the rates of bleeding was also performed. Additionally, correlation of bleeding event rates and preoperative and postoperative discontinuation of DOACs was analyzed.

RESULTS

Overall postoperative bleeding events rate was 4.9% (n = 4). Preoperative DOAC discontinuation time of <24 hours increased significantly the rate of perioperative packed red blood cell substitution (P = 0.007). Treatment with concomitant blood thinners showed a trend toward higher incidence of bleeding events (P = 0.066), whereas pre-existing kidney failure increased significantly rates of postoperative anemia (P = 0.014). The rate of postoperative thromboembolic events was 4.9% (n = 4); all events occurred with DOAC resumption >72 hours postoperatively.

CONCLUSIONS

Short preoperative discontinuation time of DOACs, even <24 hours, may be justified, considering an increased risk of perioperative packed red blood cell substitution. Care should be taken with patients treated with concomitant blood thinners and patients with pre-existing kidney disease. Postoperative DOAC resumption >72 hours may increase risk of thromboembolic events.

Implications of anticoagulant and antiplatelet therapy in patients presenting with hip fractures: a current concepts review

The increasing use of anticoagulant and antiplatelet therapy for the prevention of thromboembolic disease poses a significant challenge to orthopaedic surgeons treating elderly patients presenting with proximal femoral fractures. Early surgical intervention is known to be beneficial from a clinical perspective and has been encouraged in the UK through the introduction of best practice tariffs providing increased remuneration for prompt treatment. An understanding of the necessary delay to surgery or reversal options for each type of antiplatelet or anticoagulant agent is therefore important. A number of professional bodies have recently produced guidelines that help clinicians manage these patients during the peri-operative period. We review the guidelines relating to antiplatelet and anticoagulant agents during the perioperative period with respect to hip fracture surgery. Antiplatelet agents should not interfere with timing of surgery, but may affect the choice of anaesthetic performed. The action of warfarin should be reversed to expedite surgery. Newer direct oral anticoagulants are more problematic and surgical delay may be necessary, though reversal agents are becoming available.

Influenza vaccination might reduce the risk of ischemic stroke in patients with atrial fibrillation: A population-based cohort study

Purpose

Atrial fibrillation (AF) is associated with the risk of ischemic stroke, regardless of the administration of appropriate antithrombotic prophylaxis. This study investigated whether influenza vaccination is associated with the risk of ischemic stroke, to determine a solution to reduce this risk in patients with AF.

Methods

We used data from the Taiwan National Health Insurance Research Database. The study cohort comprised all patients diagnosed as having AF (n = 14 454) before January 1, 2005; these patients were followed until December 31, 2012. The index date was January 1, 2005. A propensity score was derived using a logistic regression model to estimate the effect of vaccination by accounting for covariates that predict receiving the intervention (vaccine). A Cox proportional hazard model was used to calculate the hazard ratios (HRs) of ischemic stroke in vaccinated and unvaccinated patients with AF.

Results

We included 6570 patients (2547 [38.77%] with and 4023 [61.23%] without influenza vaccination). The adjusted HRs (aHRs) of ischemic stroke were lower in the vaccinated patients than in the unvaccinated patients (influenza season, noninfluenza season, and all seasons: aHRs = 0.59, 0.50, and 0.55; P < 0.001, P < 0.001, and P < 0.001, respectively).

Conclusions

Influenza vaccination might exert a dose-response effect against ischemic stroke in patients with AF who have risk factors for ischemic stroke by reducing the incidence of ischemic stroke, particularly in those aged 65–74 and ≥75 y.

Risk Prediction Models in CKD

Chronic kidney disease (CKD) currently affects 20 million Americans and is associated with increased morbidity and mortality. Resource-efficient and appropriate treatment of CKD benefits the patient and provides improved resource allocation for the health care system. Prediction models can be useful in efficiently allocating resources, and currently are being used at the bedside for several important clinical decisions. There is a paucity of prediction models in use in nephrology, but one such model, the Kidney Failure Risk Equation, uses routinely collected laboratory values and can inform clinical decisions related to the following: (1) triage of nephrology referrals, (2) evaluating the need for more intensive interdisciplinary clinic care, (3) determining the timing of modality education, and (4) dialysis access planning. The development of new models that predict survival and quality of life on dialysis, success on home modalities, failure of arteriovenous fistulas, and risk of cardiovascular disease in patients with CKD is needed.

Use of the CHA2DS2VASc score to reduce utilisation of transoesophageal echocardiography prior to ablation for atrial fibrillation

Transoesophageal echocardiography (TOE) is frequently performed prior to atrial fibrillation (AF) ablation to exclude left atrial appendage (LAA) thrombus. However, patients undergoing AF ablation are usually anticoagulated, thus making the presence of thrombus unlikely in most cases. This study aimed to determine whether the CHA₂DS₂VASc scoring system can be used to identify patients that do not require TOE prior to AF ablation. In this single-centre retrospective study, local institutional and primary care databases and electronic patient records were searched to identify patients that had undergone TOE prior to AF ablation. Patient demographics, CHA₂DS₂VASc score, TOE findings and anticoagulation status were collected for analysis. Over a 7-year period (2008–2014), 332 patients (age 57 ± 10 years; 74% male) underwent TOE prior to proposed AF ablation. CHA₂DS₂VASc scores of 0, 1, 2 and >2 were found in 39, 34, 15 and 12% of patients, respectively. The prevalence of LAA thrombus was 0.6% (2 patients) and these 2 patients had risk scores of 2 and 4. No patients with a score of 0 or 1 had LAA thrombus. Patients that are classed as low risk by the CHA₂DS₂VASc score do not require a pre-ablation TOE to screen for LAA thrombus provided they are adequately anticoagulated. This would lead to a significant reduction in health care expenditures by reducing unnecessary TOE requests and thereby improve patient experience.

Association of CHADS2 and CHA2DS2-VASc Scores with Left Atrial Thrombus with Nonvalvular Atrial Fibrillation: A Single Center Based Retrospective Study in a Cohort of 2695 Chinese Subjects

The main mechanism of the CHADS₂ and CHA₂DS₂-VASc scores to predict stroke in nonvalvular atrial fibrillation (NVAF) is still controversial. We evaluated the association of the CHADS₂ and CHA₂DS₂-VASc scores with left atrial thrombus (LAT) as detected by transesophageal echocardiographic (TEE) and compared the predictive ability of these risk stratification schemes with nonvalvular atrial fibrillation (NVAF). Data from 2,695 consecutive NVAF patients in whom TEE was performed for screening LAT from July 2007 to February 2014 were analyzed. Only 3% of the subjects had LAT. Presence of LAT was not significantly associated with either CHADS₂  (P = 0.07) or CHA₂DS₂-VASc score (P = 0.12). The area under the curve (AUC) concerning LAT prediction using CHADS₂ and CHA₂DS₂-VASc was 0.574 and 0.569, respectively. A composition model includes previous stroke or transient ischemic attack, nonparoxysmal AF, moderate to severe left ventricular systolic dysfunction, left atrial enlargement, and cardiomyopathy which improved the discrimination significantly (AUC = 0.743). In our cohort, both CHADS₂ and CHA₂DS₂-VASc scores were of limited value for predicting LAT in patients with NVAF. This questions the CHADS₂/CHA₂DS₂-VASc score predicting stroke mainly through the mechanism of cardiogenic embolism. A scoring scheme combining clinical and echocardiographic parameters may better predict LAT as a surrogate for cardioembolic risk in NVAF patients.

Influenza vaccination reduces hemorrhagic stroke risk in patients with atrial fibrillation: A population-based cohort study

PURPOSE

The risk of hemorrhagic stroke in patients with atrial fibrillation (AF) is low but the consequences of its occurrence are extremely severe. In this study, we investigated the association of influenza vaccination with the risk of hemorrhagic stroke to develop an efficient strategy for reducing this risk in patients with AF.

METHODS

In this study, data were retrieved from the Taiwan National Health Insurance Research Database. The study cohort comprised all patients who received a diagnosis of AF (n=14,454) before January 1, 2005 (index date) and were followed until December 31, 2012. Propensity scores were calculated using a logistic regression model to determine the effects of vaccination by accounting for covariates that predict receiving the intervention (vaccine). A time-dependent Cox proportional hazard model was used to calculate the hazard ratios (HRs) for hemorrhagic stroke in vaccinated and unvaccinated patients with AF.

RESULTS

The study population comprised 6570 patients who did (2547 [38.77%]) and did not receive (4023 [61.23%]) influenza vaccination. The adjusted HRs (aHRs) for hemorrhagic stroke were lower in the vaccinated patients than in the unvaccinated patients (influenza season, noninfluenza season, and all seasons: aHRs=0.97 [0.59-1.60], 0.51 [0.30-0.87], and 0.72 [0.50-1.03], respectively).

CONCLUSIONS

Influenza vaccination exerts dose-response and synergistic protective effects against hemorrhagic stroke in patients with AF who have a high risk of hemorrhagic stroke (i.e., male sex, age≥75years, Charlson comorbidity index ≥3, and hypertension) and reduces the incidence of hemorrhagic stroke.

A Clinical Scoring System for Distinguishing Patients With Coincident Cubital Tunnel Syndrome Among Patients With Carpal Tunnel Syndrome

Background: Coincident carpal and cubital tunnel syndromes present a diagnostic challenge, exacerbated by the limitations of nerve conduction study (NCS) for confirming cubital tunnel syndrome. This study develops a diagnostic scoring system, the Koh-Benhaim (KB) score, to identify patients with coincident compression neuropathies. Methods: A retrospective review of 515 patients was performed from patients surgically treated for carpal and/or cubital tunnel release. These patients were divided as patients with isolated carpal tunnel syndrome (n = 337) or coincident carpal and cubital tunnel syndromes (n = 178), then characterized according to demographics, medical history, physical examination, and NCS results. Univariate and multivariate logistic regression identified predictors of coincident neuropathy. A clinical score was constructed by integerizing regression coefficients of predictive factors. Receiver operating characteristic (ROC) curves were generated for each iteration of the score. Sensitivities, specificities, and positive and negative predictive values were calculated to identify the best cutoff value. Results: Decreased intrinsic muscle strength, decreased ulnar sensation, positive elbow flexion test, positive cubital tunnel Tinel's sign, and abnormal NCS result were selected. The cutoff value for high risk of coincident compression was 3 points: positive predictive value, 82.9% and specificity, 93.4%. Model performance was very good-ROC area under the curve of 0.917. Conclusions: A KB score of 3 or greater represents high risk of coincident cubital tunnel compression. The variables involved are routinely used to assess the cubital tunnel, and all component factors of the KB score were of equivalent clinical weight in assessing patients with potential coincident compression neuropathy.

Predictive role of CHADS2 and CHA2DS2-VASc scores on stroke and thromboembolism in patients without atrial fibrillation: a meta-analysis

OBJECTIVE

CHA2DS2-VASc is the extension of the CHADS2 score developed by Birmingham 2009. This risk stratification schema is often used in clinical setting when considering additional risk factors for developing stroke in AF patients. However, its role in the non-AF population is unknown. This study was designed to evaluate the accuracy of the CHADS2 and the CHA2DS2-VASc scoring systems.

METHODS

Studies designed for CHADS2 and CHA2DS2-VASc score in stratifying the risks for stroke development in non-AF patients were included.

RESULTS

Among the 114 studies identified, six trials were chosen finally and included for meta-analysis. The pooled diagnostic odds ratio (DOR) for CHADS2 and CHA2DS2-VASc was 2.86 (95% CI =1.83-4.28) and 2.80 (95% CI =1.83-4.28), respectively. CHA2DS2-VASc score was of better sensitivity than CHADS2 score (0.920 vs. 0.768). However, both scores were showed to have inherent heterogeneity and poor specificity.

CONCLUSIONS

Though having good diagnostic accuracy, the clinical application of the CHADS2 and CHA2DS2-VASc scores in predicting risk of stroke development in non-AF patients still needs further validation. Key message The overall diagnostic accuracy of CHADS2 and CHA2DS2-VASc in stroke-risk stratification was good in patients with non-atrial fibrillation.

Transesophageal Echocardiography in Atrial Fibrillation

Transesophageal echocardiography (TEE) plays an important role in atrial fibrillation (AF), mainly to detect the presence of left atrial appendage (LAA) thrombus. It is useful in direct current cardioversion (DCC) guidance and for AF ablation and LAA occlusion. With the increasing number of patients affected by AF, the use of TEE will grow and become an important screening modality for LAA thrombus. Future direction includes broader multi-institutional use; further tools to risk stratify patients; and the use of a new spectrum of oral anticoagulants and their cost-effectiveness in patients with AF undergoing DCC, AF ablation, and LAA occlusion.

Prevalence and Clinical Determinants of Left Atrial Appendage Thrombus in Patients With Atrial Fibrillation Before Pulmonary Vein Isolation

The CHADS2 score is considered a reliable predictor of stroke/thromboembolism risk in patients with atrial fibrillation (AF). However, thromboembolism can occasionally occur even in patients with AF with low CHADS2 score (CHADS2 score = 0 or 1). To investigate the incidence and predictors of left atrial appendage (LAA) thrombus (LAAT) formation in patients with AF, we studied consecutive 543 Japanese patients with AF who underwent transesophageal echocardiography before pulmonary vein isolation from 2008 to 2012. All patients were treated with anticoagulation therapy with warfarin, and their clinical and echocardiographic characteristics were evaluated. LAATs were observed in 35 (6.4%) of 543 patients, and the prevalence was clearly correlated with the patient's CHADS2 scores. Of 338 patients with low CHADS2 score, LAATs were observed in 7 patients (2.1%). By multivariate analysis, increased left atrial volume (≥50 ml), decreased ejection fraction (<56%), and increased brain natriuretic peptide level (>75 pg/ml) were significantly associated with increased prevalence of LAATs, even in patients with low CHADS2 score. Accordingly, we proposed a new scoring system to predict LAAT (left atrial volume ≥50 ml: score 2; ejection fraction <56%: score 1; brain natriuretic peptide >75 pg/ml: score 1). Patients with a score ≥2 have a greater risk of LAAT, whereas all patients with score ≤1 have no LAATs. Our scoring system is useful for evaluation of the risk of LAAT in patients with AF even with low CHADS2 score.

Novel Oral Anticoagulants for DC Cardioversion Procedures: Utilization and Clinical Outcomes Compared with Warfarin

BACKGROUND

Novel oral anticoagulant (NOAC) agents dabigatran, rivaroxaban, and apixaban are increasingly utilized as thromboembolic prevention for patients with atrial fibrillation undergoing direct current cardioversion (DCCV) with post hoc analyses of clinical trials suggesting satisfactory safety and efficacy. This study characterizes utilization, effectiveness, and complications of NOAC agents for stroke prophylaxis in the setting of DCCV.

METHODS

Comparison of warfarin and NOAC agents as periprocedural anticoagulation for DCCV procedures performed at Cleveland Clinic from January 2009 through December 2013. Variables of interest include utilization rates for each NOAC agent stratified by clinical parameters including CHADS2 score, and associated clinical outcomes including cerebrovascular accident (CVA), transient ischemic attack (TIA), peripheral arterial embolism (PAE), and bleeding events during 8 weeks of postprocedure follow-up.

RESULTS

Among 5,320 DCCV procedures, 673 (12.6%) cases were excluded due to inadequate follow-up. Warfarin was utilized in 3,721 (80.1%), dabigatran in 719 (15.5%), rivaroxaban in 159 (3.4%), and apixaban in 48 (1.0%) with a steady increase in NOAC utilization from 2011 to 2013. There were low rates of CVA/TIA (warfarin: 0.97% vs NOAC 1.62%, P = 0.162) and bleeding (warfarin: 1.02% vs NOAC: 0.5%, P = 0.247) and no significant differences detected between agents. Higher CHADS2 /CHA2 DS2 -VASC scores were associated with thromboembolic and bleeding risk. Increasing age, chronic kidney disease, diabetes, coronary disease, and deep vein thrombosis/pulmonary embolism were associated with increased bleeding risk.

CONCLUSION

In a high-volume, single-center experience, NOAC utilization has grown to account for over a third of cardioversion procedures, and these agents appear safe and effective compared to warfarin with low rates of thromboembolic and bleeding complications.

Prevalence of intracardiac thrombi under phenprocoumon, direct oral anticoagulants (dabigatran and rivaroxaban), and bridging therapy in patients with atrial fibrillation and flutter

Direct oral anticoagulants (DOACs) are effective for stroke prevention in nonvalvular atrial fibrillation (AF). Cardioversion (CV) is frequently performed in patients with AF or flutter. To further explore the safety profile of DOACs in the context of CV, we sought to assess the prevalence of intracardiac thrombi under DOAC therapy in comparison with treatment with vitamin K antagonists. A total of 672 transesophageal echocardiograms performed in 643 patients with a history of nonvalvular AF were analyzed. The median CHA2DS2-VASc score was 4. Cases were stratified according to anticoagulation with dabigatran (n = 79), rivaroxaban (n = 122), phenprocoumon (n = 180), or bridging therapy (n = 287). In a subgroup analysis, only patients receiving phenprocoumon with an international normalized ratio ≥2 on the day of the investigation or on DOAC therapy for ≥3 weeks were considered. The prevalence of intracardiac thrombi under phenprocoumon was significantly higher than under DOACs (phenprocoumon, 17.8%; all DOACs, 3.9%; dabigatran, 3.8%; rivaroxaban, 4.1%) and showed no significant difference to bridging therapy (12.5%). In patients with sufficient short-term anticoagulation, similar differences between DOAC and phenprocoumon groups were observed (phenprocoumon, 18.4%; all DOACs, 3.8%; dabigatran, 0%; rivaroxaban, 6.6%). The influence of anticoagulation medication on thrombus rates was confirmed after adjusting for baseline intergroup differences regarding left atrial size and CHA2DS2-VASc score. In conclusion, the prevalence of intracardiac thrombi was lower under DOAC therapy than under phenprocoumon in this high-risk patient cohort. Safety of CV during DOAC treatment requires further prospective evaluation.

Which risk score best predicts perioperative outcomes in nonvalvular atrial fibrillation patients undergoing noncardiac surgery?

BACKGROUND

Patients with nonvalvular atrial fibrillation (NVAF) are at increased risk for adverse events after noncardiac surgery. The Revised Cardiac Index (RCI) is commonly used to predict perioperative events; however, the prognostic utility of NVAF risk scores (CHADS2, CHA2DS2-VASc, and R2CHADS2) has not been evaluated in patients undergoing noncardiac surgery.

METHODS

Using a population-based data set of NVAF patients (n = 32,160) who underwent major or minor noncardiac surgery between April 1, 1999, and November 30, 2009, in Alberta, Canada, we examined the incremental prognostic value of the CHADS2, CHA2DS2-VASc, and R2CHADS2 scores over the RCI using continuous net reclassification improvement (NRI). The primary composite outcome was 30-day mortality, stroke, transient ischemic attack, or systemic embolism.

RESULTS

The median age was 73 years, 55.1% were male, 6.6% had a previous thromboembolism, 17% of patients underwent major surgery, and the median risk scores were as follows: RCI = 1, CHADS2 = 1, CHA2DS2-VASc = 3, and R2CHADS2 = 2. The incidence of our 30-day composite was 4.2% (mortality 3.3%; stroke, transient ischemic attack, or systemic embolism 1.2%); and c indices were 0.65 for the RCI, 0.67 for the CHADS2 (NRI 14.3%, P < .001), 0.67 for CHA2DS2-VASc (NRI 10.7%, P < .001), and 0.68 for R2CHADS2 (NRI 11.4%, P < .001). The CHADS2, CHA2DS2-VASc, and R2CHADS2 scores were also all significantly better than the RCI for mortality risk prediction (NRI 12.3%, 8.4%, and 13.3%, respectively; all Ps < .01).

CONCLUSIONS

In NVAF patients undergoing noncardiac surgery, the CHADS2, CHA2DS2-VASc, and R2CHADS2 scores all improved the prediction of major perioperative events including mortality compared to the RCI.

The CHA2DS2-VASc score as a predictor of left atrial thrombus in patients with non-valvular atrial fibrillation

OBJECTIVE

To investigate whether or not the CHA2DS2-VASc score predicts left atrial (LA) thrombus detected on pre-cardioversion transoesophageal echocardiography (TEE).

MATERIALS AND METHODS

The medical records of patients who had undergone TEE were reviewed to assess the presence of LA thrombus prior to direct-current cardioversion for atrial fibrillation (AF). The CHA2DS2-VASc score was calculated for each patient. Clinical TEE reports were reviewed for the presence of LA thrombus. Patients with a valve prosthesis or rheumatic mitral valve disease were excluded from this study.

RESULTS

A total of 309 patients were identified. The mean age was 70.1 ± 9.8 years and 151 (49%) patients were males and 158 (51%) were females. LA thrombus was seen in 32 (10.3%) of the 309 patients. Fifty (16.2%) patients had a low CHA2DS2-VASc score (0-1), 230 (74.4%) had an intermediate score (2-4) and 29 (9.4%) had a high score (5-9). The incidence of LA thrombus in the low, intermediate and high CHA2DS2-VASc score groups was 0, 4.4 and 68.7%, respectively. The LA thrombus risk increased with increasing CHA2DS2-VASc scores. On multivariate logistic analysis, the CHA2DS2-VASc score (OR 3.26, 95% CI 2.3-4.65; p = 0.001) and age (OR 0.93, 95% CI 0.88-0.98; p = 0.004) were independent risk factors for LA thrombus in patients with non-valvular AF.

CONCLUSION

A high CHA2DS2-VASc score was independently associated with the presence of LA thrombus in patients with non-valvular AF.

Clinical significance of the assessment of the systolic and diastolic myocardial function of the left atrium in patients with paroxysmal atrial fibrillation and low CHADS(2) index treated with catheter ablation therapy

The purpose of this study was to determine the clinical significance of the assessment of the diastolic and systolic myocardial function of the left atrium in patients with paroxysmal atrial fibrillation (AF) and low CHADS(2) scores treated with catheter ablation therapy. In a cohort of 84 symptomatic patients with paroxysmal AF and low CHADS(2) scores (≤1), the clinical significance of the systolic and diastolic myocardial function of the left atrium (assessed using 2-dimensional speckle-tracking echocardiography) were studied to predict the risk for recurrence of AF after catheter ablation therapy in the course of a follow-up period of ≥1 year. During a mean follow-up period of 19.2 ± 5.4 months, patients with left atrial (LA) myocardial diastolic dysfunction (LA strain <18.8%) had a significantly higher rate of recurrence of AF (42.4% vs 9.8%, p <0.05) compared to those without LA diastolic dysfunction. In line with this finding, patients with impaired LA myocardial systolic function (LA strain rate >-0.85 s(-1)) had worse outcomes after catheter ablation therapy than those with normal LA systolic function (rate of recurrence of AF 42.9% vs 12.5%, respectively, p <0.05). In relation to these results, in a logistic regression analysis including co-morbidities, left ventricular dysfunction, LA enlargement, and LA myocardial alterations, diastolic and systolic LA myocardial dysfunction were the principal variable associated with the recurrence of AF (odds ratios 6.8 and 5.2, respectively). In conclusion, in symptomatic patients with paroxysmal AF and low CHADS(2) scores, these findings suggest that the assessment of diastolic and systolic LA myocardial function using 2-dimensional speckle-tracking echocardiography could be of great utility to distinguish those patients with high or low risk for recurrence of AF after catheter ablation therapy.

CHADS(2) and CHA(2)DS (2)-VASc score of patients with atrial fibrillation or flutter and newly detected left atrial thrombus

BACKGROUND

The risk of developing a stroke or systemic embolus due to a left atrial (LA) thrombus in patients with atrial fibrillation (AF) and/or atrial flutter (AFL) is estimated by the CHADS(2) score and more recently the CHA(2)DS(2)-VASc score. We aimed to further characterize AF/AFL patients who were found to have a LA thrombus on a transesophageal echocardiogram (TEE).

METHODS AND RESULTS

Of 3,165 TEE between 2005 and 2011 for a broad spectrum of indications, we detected 65 AF patients with LA thrombus (2 %). There were 40 men and 25 women, mean age was 65 ± 13 years (range 36-88 years). Mean CHADS(2) score was 1.8 ± 1.1 and mean CHA(2)DS(2)-VASc score was 3.0 ± 1.6. 11 patients (17 %) had a CHADS(2) score of 0, 12 patients (18 %) of 1, 28 patients (43 %) of 2 and 12 patients (18 %) of 3. Hypertension was the most frequent risk factor (72 %), followed by congestive heart failure (32 %), diabetes (23 %) and age ≥75 years (23 %). Mean difference between CHADS(2) and CHA(2)DS(2)-VASc was 1.25 ± 0.91. Of the 11 patients (17 %) with a LA thrombus despite a CHADS(2) score of 0, five had a CHA(2)DS(2)-VASc score of 0, four a CHA(2)DS(2)-VASc score of 1 and two a CHA(2)DS(2)-VASc score of 2.

CONCLUSION

In an unselected TEE population with newly detected LA thrombus about one-third of patients fell into the low-risk group when classified based on the CHADS(2) score, while a much lower population fell in the same low-risk group when classified according to the CHA(2)DS(2)-VASc score. However, this does not prove clinical superiority of the CHA(2)DS(2)-VASc score over the established CHADS(2) score. Whether our observation has clinical implications (e.g. TEE prior to LA ablation irrespective of CHADS(2) score), or argues for use of the CHA(2)DS(2)-VASc score needs to be evaluated in prospective studies.