Presence Of Paroxysmal Atrial Fibrillation Research Articles

Metformin reduces new-onset atrial fibrillation risk rather than atrial fibrillation burden in type 2 diabetes patients: A case-control study

BackgroundThe effects of metformin on atrial fibrillation (AF) in type 2 diabetes patients remain unclear. We aimed to explore the effects of metformin on AF, including new-onset AF and AF burden, in type 2 diabetes patients with pacemakers. Methods and resultsThis retrospective study included a total of 227 patients. Based on the presence of paroxysmal AF, the patients were divided into a paroxysmal AF group (n = 80) and a non-AF group (n = 147). In the non-AF group, a significant association was observed between metformin use and a lower risk of new-onset AF in multivariable Cox hazards models (hazard ratio [HR]: 0.36; 95 % confidence interval [CI]: 0.14–0.91; p = 0.0311*) when adjusted for age, sex, body mass index (BMI), drinking, smoking, left atrial dimension, creatinine, complications, and drugs. In the paroxysmal AF group, univariable analysis indicated no association between the AF burden and metformin use (p = 0.817). Furthermore, when adjusted for metformin use, age, sex, BMI, drinking, smoking, cardiovascular disease, myocardial infarction, heart failure, stroke, and ejection fraction in multivariable Cox hazards models, we found a lower proportion of major adverse cardiovascular events (MACEs) both in the total (HR: 0.28; 95 % CI: 0.1–0.82; p = 0.0202*) and the non-AF group (HR: 0.19; 95 % CI: 0.05–0.79; p = 0.0223*) compared to that in the AF group (HR: 0.31; 95 % CI: 0.02–4.41; p = 0.3879). ConclusionIn type 2 diabetes patients with pacemakers, metformin reduced the probability of new-onset AF instead of addressing the AF burden. Furthermore, metformin therapy decreased the incidence of MACEs in type 2 diabetes patients without AF.

The role of the TAPSE/PASP ratio in the prediction of paroxysmal atrial fibrillation in patients with acute ischemic stroke

Aims: Atrial fibrillation (AF) remains the most prevalent cause of cardioembolic stroke. Paroxysmal AF (PAF) is often difficult to be diagnosed and is sometimes first detected during embolic stroke. Yet, TAPSE and PASP can be easily revealed in routine transthoracic echocardiography (TTE). Then, the TAPSE/PASP ratio is often shown to have prognostic significance in many cardiac disorders. Nevertheless, the insufficient scholarly knowledge of the relationship between this ratio and the development of PAF became the primary motive of the present study.
 Methods: We carried out this study with 114 patients experiencing acute ischemic stroke without a previous diagnosis of AF. We noted down the patients’ blood parameters and prescribed drugs and calculated TAPSE/PASP ratio relying on their TTE findings. We also recorded the 24-hour heart rhythm findings of each patient through Holter monitoring. After categorizing PAF attacks (i.e.,PAF attack was (not) observed), we explored any statistical relationship between the TAPSE/PASP ratio and the presence of PAF.
 Results: The findings revealed a significant difference between the TAPSE/PASP ratios between the groups with PAF (0.62±0.07) and without PAF (0.77±0.08). Moreover, the receiver operating characteristic (ROC) curve analysis yielded the TAPSE/PASP ratio to demonstrate a diagnostic value in predicting PAF (area under the ROC curve [AUC]=0.89;82.7%; p

Machine learning model to predict the presence of paroxysmal atrial fibrillation in patients with hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Romanian Ministry of National Education, CNCS-UEFISCDI. Background Atrial fibrillation (AF) is the most frequent arrhythmia in hypertrophic cardiomyopathy (HCM), with a major impact on overall survival, thromboembolic risk, and quality of life. Early recognition and treatment of AF are essential to improve the outcome of HCM patients (pts). Despite the existence of several independent predictors of AF development, the identification of HCM pts at risk for AF is still inconsistent. The identification, quantification, and interpretation of the relationships between different clinical and imaging-derived variables may lead to improved risk stratification and prognosis. Predictive models based on machine learning (ML) could reduce variability while providing useful new medical knowledge. Purpose Develop a ML model (emerging from the integration of clinical and echocardiographic data) capable of accurately detecting HCM pts with AF. Methods A comprehensive clinical and echocardiographic assessment was performed in 151 consecutive pts (52±16 years, 72 men) with HCM, in sinus rhythm. Pts were divided into two groups according to the presence (38 pts) or absence (113 pts) of documented paroxysmal AF (24/48 h ambulatory ECG recordings). 81 features (clinical and echocardiographic parameters) were considered as input to the ML models. Four different ML models were evaluated: Deep Learning (DL), Linear Logistic Regression (LLR), Support Vector Machine (SVM) and Random Forest (RF). Ensemble learning and four-fold cross-validation were employed in all experiments. For each experiment the training dataset was augmented and balanced using the Synthetic Minority Over-sampling Technique. The models were fine-tuned using the following hyper-parameters: learning rate, batch size, number of hidden layers, and number of features used as input. The features were first ranked using the Recursive Feature Elimination method, and the top N features were selected during the hyper-parameter tuning. Results Each ML model was trained for 100 epochs, and the results were extracted from the epoch that led to the best results when combining all four folds. DL was the best performing model, with a learning rate of 0.01, a batch size of 32, 4 hidden layers (256/128/128/64 neurons), and 15 input features. The DL model had 5% higher accuracy compared to LLR, 10% higher than SVM and 8% higher than RF, with consistently higher sensitivity. The performance of the various models is detailed in the table below. Moreover, the DL model had significantly higher accuracy compared to conventional imaging parameters consistently related to the presence of AF in previous studies, such as maximum LA volume (AUC 0.66, accuracy 59%) or LA strain (AUC 0.61, accuracy 62%). Conclusions The DL based model can detect the presence of paroxysmal AF in patients with HCM with an accuracy of 84% (5% higher than the best classic ML model, and significantly higher than independent conventional imaging parameters).

New-Onset Paroxysmal Atrial Fibrillation in the Setting of Acute Pulmonary Embolism Is Associated with All-Cause Hospital Mortality in Women but Not in Men.

Patients with acute pulmonary embolism (PE) may have various types of atrial fibrillation (AF). The role of AF in hemodynamic states and outcomes may differ between men and women. In total, 1600 patients (743 males and 857 females) with acute PE were enrolled in this study. The severity of PE was assessed using the European Society of Cardiology (ESC) mortality risk model. Patients were allocated into three groups according to their electrocardiography recordings taken during hospitalization: sinus rhythm, new-onset paroxysmal AF, and persistent/permanent AF. The association between the types of AF and all-cause hospital mortality was tested using regression models and net reclassification index (NRI) and integrated discrimination index (IDI) statistics with respect to sex. There were no differences between the frequencies of the types of AF between men and women: 8.1% vs. 9.1% and 7.5% vs. 7.5% (p = 0.766) for paroxysmal and persistent/permanent AF, respectively. We found that the rates of paroxysmal AF significantly increased across the mortality risk strata in both sexes. Among the types of AF, the presence of paroxysmal AF had a predictive value for all-cause hospital mortality independent of mortality risk and age in women only (adjusted HR, 2.072; 95% CI, 1.274-3.371; p = 0.003). Adding paroxysmal AF to the ESC risk model did not improve the reclassification of patient risk for the prediction of all-cause mortality, but instead enhanced the discriminative power of the existing model in women only (NRI, not significant; IDI, 0.022 (95% CI, 0.004-0.063); p = 0.013). The occurrence of paroxysmal AF in female patients with acute PE has predictive value for all-cause hospital mortality independent of age and mortality risk.

Clues on electrocardiography to predict the presence of paroxysmal atrial fibrillation in patients with acute ischemic stroke: A propensity score-matched study

Cardiovascular Surgery and Interventions publishes original articles on topics in cardiovascular surgery, cardiovascular anesthesia and cardiology. These encompass all relevant clinical, surgical and laboratory studies, editorials, current and collective reviews, technical know-how papers, case reports, interesting images, “How to Do It” papers, correspondence and commentary.

B-PO05-039 MET SCORE IN PATIENTS WITH AND WITHOUT ATRIAL FIBRILLATION

Patients (pts) with paroxysmal atrial fibrillation (PAF) often report markedly reduced activity levels in daily life, which is associated with adverse outcome. Activity is a modifiable risk factor for AF progression. Accelerometer data can be used to objectively assess the daily metabolic equivalent of task (MET) score. We aimed to investigate the association between MET score during sinus rhythm (SR) in PAF pts, using a 30 day mobile cardiac telemetry device with integrated accelerometer data. Pts 50-85 years old who recorded an ambulatory ECG with sufficient quality using the PocketECG device (MediLynx) in the US during 2019, to assess, ICD10 codes I48.xx or R00.2, were included. Subjects with PAF-burden ≥ 20% were excluded. MET score during SR was compared in pts with and without PAF with a duration ≥30s. All PAF episodes were algorithmically detected and manually verified. The population consisted of 1,096 men and 1,591 women (mean age 70.1 and 69.7 years, respectively, A), of whom 14.4% (n=386) pts were diagnosed with PAF (13.8% of women and 15.2% of men, p = 0.31). Pts with PAF had a significantly lower MET score during SR (B), compared to pts without PAF (1.24 vs. 1.32; 95% CI of the difference: [-0.11; -0.06]), as did women compared to men (1.29 vs. 1.34; 95% CI of the difference: [-0.07; -0.02]). Interaction of sex and presence of PAF was not significant (95% CI: [-0.04; 0.08]). Patients with PAF are less active during sinus rhythm than patients without AF. Future studies are needed to determine whether MET measurement could identify subjects at risk of progression or recurrence post-ablation, who may benefit from targeted interventions.

Prevalence of paroxysmal atrial fibrillation in patients presenting with embolic stroke of undetermined source

Background: Cerebrovascular stroke is a major cause of morbidity and disability. Many etiologies may contribute to its presence. Some patients have none of the identifiable risk factors yet face the consequences of stroke or transit ischemic attack. This type of stroke is known as embolic stroke of undetermined source (ESUS). It has a high rate of recurrence due to the presence of an unknown uncorrected etiology. Paroxysmal atrial fibrillation remains a hidden bottom of an iceberg, representing a major hidden etiology of ESUS. We aimed to determine the prevalence of paroxysmal atrial fibrillation in patients with ESUS using 72-h Holter monitoring. Methods: Patients diagnosed with ESUS underwent 72-h Holter monitoring within the 1st week of the incident stroke. Holter monitors determined whether atrial fibrillation (more than 3 s) is present or not. Results: This study included 200 patients with stroke of an undetermined source who underwent 72-h Holter monitoring within 1 week of the incident stroke. The patients' ages ranged between 22 and 77 years (mean age 48.46 ± 12.74 years); 136 were males and body mass index (BMI) ranged from 21 to 35 kg/m2, with a mean BMI of 24.78 ± 2.99 kg/m2. Their left atrial anteroposterior diameter in the parasternal long-axis view ranged from 26 mm to 47 mm, with a mean diameter of 36.08 ± 5.23 mm. Thirty-two out of the 200 patients were diagnosed with paroxysmal atrial fibrillation, representing 16%. There was a statistically significant association between the presence of paroxysmal atrial fibrillation and both age (P = 0.009) and left atrial diameter (P = 0.001). There was an associated finding that needs further investigation regarding the significant association between supraventricular ectopic beats and the presence of atrial fibrillation or stroke. Conclusion: Paroxysmal atrial fibrillation is an important hidden etiology of embolic stroke of undetermined etiology that can be detected early using 72-h Holter monitoring within 1 week of the incident stroke.

Diagnostic Values of Some Fibrinolytic Indicators for Rejecting the Presence of Paroxysmal Atrial Fibrillation

Diagnostic tests are a cornerstone in modern medicine. They are used not only to confirm the presence of a disease but also to rule out the disease in healthy subjects. Tests with two outcome categories (i.e. presence/absence) are known as dichotomous tests. Their inherent validity is determined by sensitivity and specificity and the receiver operating characteristic (ROC) curve is known to be a simple, yet complete plot that displays the full picture of trade-off between the sensitivity (true positive rate) and (1- specificity) (false positive rate) across a series of cut-off points. Our study found that, even in the early hours of paroxysmal atrial fibrillation, there were significant changes in major indicators of fibrinolysis, namely plasminogen level, t-PA level, PAI-1 activity, α2-antiplasmin activity, vitronectin and D-dimer plasma levels. We believe that they are closely related and stem from the disease itself. This gave us reason, using these indicators as predictors, to search for a diagnostic option to rule out PAF. We used statistical models of logistic regression analysis and ROC to achieve this. Values of p<0.05 were considered statistically significant. Plasma levels of vitronectin have been found to be the most reliable predictor for ruling out PAF (specificity 88%, sensitivity 83%, AUC 0.96), while D-dimer levels had the lowest diagnostic values (37% specificity, 81% sensitivity, AUC 0.56). The obtained results are not only of pure scientific but also of applied nature. They could be used to improve identification of patients at risk for PAF embolism, and assist in the choice of thromboprophylaxis.

P827 Left atrial contractile function is the main correlate of atrial fibrillation in patients with hypertrophic cardiomyopathy

Abstract Background Given the negative impact of atrial fibrillation (AF) in patients (pts) with hypertrophic cardiomyopathy (HCM), finding new and better predictors of AF is clinically important, especially for patients considered at low or intermediate risk based on current recommendations (i.e. left atrial diameter, LAD <45 mm). Purpose To assess the relationship between left atrial (LA) remodelling (size and function) and the presence of paroxysmal AF in HCM patients with and without increased LAD. Methods A comprehensive echocardiogram was performed in 110 consecutive pts (52 ± 17 years, 50 men) with HCM, in sinus rhythm. Indexed LA volume (LAVi), maximum left ventricular wall thickness (LVWT), LV ejection fraction, E/e’ ratio were determined. Global longitudinal LV strain (GLS) and LA strain parameters (LAɛ, SSr, ASr) were assessed by speckle tracking echocardiography. Patients were divided into two groups according to the presence (30 pts) or absence (80 pts) of documented paroxysmal AF (24/48 h ambulatory ECG recordings) Results Patients with AF were older than pts without AF (p < 0.001). LAD, LAVi, E/e’ were significantly higher, while LAɛ, ESr, ASr were significantly lower in pts with AF compared to pts without AF (p < 0.05 for all). There were no significant differences between pts with and without AF regarding: gender, LVWT, GLS, the presence and severity of LV outflow tract obstruction (p > 0.05 for all). The correlates of AF in the whole HCM study population were: age (OR = 1.05, p = 0.001), ASr (OR = 10.1, p < 0.001), LAVi (OR = 1.03, p = 0.004), LAD (OR = 1.2, p = 0.001), E/e’(OR = 1.05, p = 0.02) and mitral regurgitation degree (OR = 1.6, p = 0.04). ASr had the best area under the curve (AUC: 0.74) with a cutoff of -0.88 s-1 for identifying HCM patients with AF (sensitivity: 80%, specificity: 65%). At multivariable logistic regression analysis, age, LAVi and ASr emerged as the only independent correlates of AF. 14 of the 71 patients with a LAD < 45 mm had paroxysmal AF. In this selected population, pts with AF were older (p = 0.001), had higher values for E/e’ (p = 0.04) and lower values for ASr (p = 0.02) than pts without AF. Moreover, in this subgroup of pts, at multivariable logistic regression analysis, ASr correlated with AF independently of age, LA dimensions, LV hypertrophy or E/e’ (OR = 10.008, 95% CI 1.297-77.219, p = 0.02). Conclusions In pts with HCM, age, LAVi and ASr, were independently related to the presence of AF, while LAD was not. Moreover, in the subgroup of HCM pts with LAD < 45 mm, ASr (reflecting LA contractile function) was the only LA remodelling parameter correlated with the presence of AF. The assessment of LA volume and function can provide further insights into the risk stratification of pts with HCM, especially in pts considered at lower risk for AF based on the assessment of classical risk parameters, such as LAD.

Atrial fibrillation trial to evaluate real-world procedures for their utility in helping to lower stroke events (AFTER-PULSE): Study protocol for a randomized controlled trial.

BackgroundEnhancing detection of undiagnosed atrial fibrillation (AF) in hospitalized patients with a recent ischemic stroke is important because of the treatment implications; especially since presence of paroxysmal AF may not be picked up in a single 12-lead electrocardiogram (ECG) test. While several trials have shown improved detection of AF with prolonged ECG monitoring, this strategy is associated with relatively high cost, labor intensity, and patient inconvenience, thereby making it challenging to routinely implement in all hospitals. Fortunately, conventional 24-h Holter monitoring and repeated 12-lead ECGs are readily available to detect paroxysmal AF in all hospitals, but is unclear which is the better strategy for evaluating undiagnosed AF. The objective of his study is to conduct a randomized trial of serial 12-lead ECGs vs. 24-hour Holter monitoring in the detection of AF in ischemic stroke patients without known AF.Methods and analysisWe plan to enroll 1200 participants from six hospitals in Taiwan. Patients will be eligible for enrollment if they are admitted for an acute ischemic stroke within 2 days, are ≥65 years of age, and have no known AF by history or on baseline ECG at admission. We will randomly assign participants in a 1:1 ratio to undergo daily 12-lead ECG once daily for 5 days (intervention group) or 24-h Holter monitoring (control group). Primary outcome is newly detected AF on a 12-lead ECG or AF lasting ≥30 s on Holter monitoring.Trial registration numberClinicalTrials.gov Identifier: NCT02578979.

Abstract 12671: Left Atrial Volumes Corrected for Heart Size are Superior Echocardiographic Measures for Diagnosing Paroxysmal Atrial Fibrillation in Ischemic Stroke and Transient Ischemic Attack Patients

Introduction: The underlying cause of ischemic strokes (IS) and transient ischemic attacks (TIA) is not identified in 25% of the cases. However, asymptomatic paroxysmal atrial fibrillation (PAF) is often assumed to be the cause of the cryptogenic IS or TIA Hypothesis: The aim of this study was to examine if echocardiographic measures of LA volume (LAV) corrected for the left ventricular (LV) length (LAVMax/Min/LV length) could predict PAF in patients with IS and TIA. Methods: We retrospectively included 218 patients who after acute IS or TIA underwent a transthoracic echocardiographic examination in sinus rhythm. Patients were designated as PAF-patients if they had one or more reported incidents of AF before or after their echocardiographic examination. Results: Patients in the PAF group were significantly older (62±13 vs. 52±14 years, p<0.001), had higher CHA2DS2-VASc score (3.3±1.3 vs. 3.8±1.3, p=0.042) and higher National Institutes of Health Stroke Scale (NIHSS) score (2.9±4.9 vs. 1.4±3.3, p=0.016) than patients without PAF. Besides these, no other baseline characteristics (sex, hypertension, diabetes, cholesterol) were associated with PAF. None of the conventional echocardiographic parameters (LV ejection fraction, LV volumes, E/A-ratio, E-wave deceleration time, LAVmax) were significantly associated with PAF. However, the atrial measures corrected for LV length (LAVMax/LV length and LAVMin/LV length) were significantly higher (LAVMax/LV length: 7.6±3.3 mL/cm vs. 6.5± 2.0 mL/cm, p=0.009; LAVMin/LV length: 3.7± 2.1 mL/cm vs. 2.8±1.1 mL/cm, p<0.001) in patients with PAF (Figure), even after adjustment for age, gender, CHA2DS2-VASc and NIHSS scores. Conclusion: In patients with IS and TIA, measures of LA size corrected for LV length are independently associated with the presence of PAF. Applying these may yield better risk stratification for PAF-presence in patients suffering cryptogenic IS and TIA.

Three-Dimensional Speckle Tracking Imaging for Assessing Left Atrial Function in Hypertensive Patients With Paroxysmal Atrial Fibrillation.

Hypertension (HT) is known to be the most prevalent risk factor for paroxysmal atrial fibrillation (PAF), however, its mechanisms have not been fully clarified. Our aim was to investigate the differences in left atrial (LA) function between healthy subjects, and hypertensive patients without PAF (HT-PAF(-)) and with PAF (HT-PAF(+)) using 3-dimensional (3D) speckle tracking imaging (STI). A total of 144 subjects were enrolled: 44 HT-PAF(+) (27 males; mean age 69 ± 10 years), 50 HT-PAF(-) (31 males; mean age 63 ± 11 years), and 50 controls (31 males; mean age 51 ± 14 years). All subjects were in sinus rhythm during the examination. LA volume, LA emptying fraction (LAEF), and LA wall strain were analyzed by 3D area tracking imaging. The maximal value of the global strain curve was defined as the peak global strain. The standard deviation of the time from the R-wave on the electrocardiogram to peak positive values of the segmental strain curves corrected by the R-R' interval in 6 mid LA segments (TP-SD) was calculated to assess LA dyssynchrony. LAEF and peak global strain were lower in HT-PAF(+) than in HT-PAF(-) (P < 0.01) and in the control (P < 0.01). Moreover, TP-SD was higher in HT-PAF(+) than in HT-PAF(-) (P < 0.05) and in the control (P < 0.01). Multivariate analysis revealed LA volume index, peak global strain, and TP-SD were independent determinants of HT-PAF(+). The presence of PAF is associated with diminished LA compliance and advanced mechanical dyssynchrony, as well as LA geometric deformation.

Elevated Serum Beta-Trace Protein Levels are Associated With the Presence of Atrial Fibrillation in Hypertension Patients.

Beta-trace protein (BTP) has emerged as a novel biomarker of cardiovascular risk. In this study, the authors aimed to assess the relationship between BTP levels and presence of atrial fibrillation in patients who had controlled hypertension (HTN) and normal renal function. A total of 80 controlled HTN patients with paroxysmal atrial fibrillation (PAF) and 80 age- and sex-matched controls with controlled HTN were enrolled. Serum BTP levels were measured by enzyme-linked immunosorbent assay. BTP levels were found to be significantly higher in patients with PAF (P<.001). Other parameters including mean systolic and diastolic blood pressure values, serum creatinine levels, and glomerular filtration rate were similar between the two groups. Along with left atrial diameter (odds ratio, 1.504; P<.001), BTP levels (odds ratio, 1.015; P<.001) were independently associated with the presence of PAF. BTP levels were increased in controlled HTN patients with PAF compared with controls, and this association was observed within normal renal functions as reflected by normal glomerular filtration rate.

Arterial stiffness determined according to the cardio-ankle vascular index is associated with paroxysmal atrial fibrillation: a cross-sectional study

BackgroundSeveral lines of evidence suggest that atrial fibrillation (AF) may be a consequence of vascular disease. We investigated the relationship between cardio-ankle vascular index (CAVI), a new index of arterial...

Three-Dimensional Analysis of the Left Atrial Appendage for Detecting Paroxysmal Atrial Fibrillation in Acute Ischemic Stroke

Atrial fibrillation impairs left atrial appendage function and the thrombus formation in the left atrial appendage is a major cause of cardioembolic stroke. To evaluate the association between the volume of the left atrial appendage measured by real-time three-dimensional transesophageal echocardiography and presence of paroxysmal atrial fibrillation in patients with cerebral infarction or transient ischemic attack. Real-time three-dimensional transesophageal echocardiography was performed to measure left atrial appendage end-diastolic and end-systolic volumes to calculate left atrial appendage ejection fraction. Patients with normal sinus rhythm at the time of real-time three-dimensional transesophageal echocardiography were divided into groups with and without paroxysmal atrial fibrillation. Volumetric data were corrected with the body surface area. Of 146 patients registered, 102 (29 women, 72·2 ± 10·7 years) were normal sinus rhythm at the examination. In 23 patients with paroxysmal atrial fibrillation, left atrial appendage end-diastolic volume (4·78 ± 3·00 ml/m(2) vs. 3·14 ± 2·04 ml/m(2), P = 0·003) and end-systolic volume (3·10 ± 2·47 ml/m(2) vs. 1·39 ± 1·56 ml/m(2), P < 0·001) were larger and left atrial appendage ejection fraction (37·3 ± 19·1% vs. 57·1 ± 17·5%, P < 0·001) was lower than in the other 79 patients without paroxysmal atrial fibrillation. The optimal cutoff for left atrial appendage peak flow velocity to predict paroxysmal atrial fibrillation was 39·0 cm/s (sensitivity, 54·6%; specificity, 89·7%; c-statistic, 0·762). The cutoffs for left atrial appendage end-diastolic volume, end-systolic volume, and ejection fraction were 4·52 ml/m(2) (sensitivity, 47·8%; specificity, 82·3%; c-statistic, 0·694), 1·26 ml/m(2) (sensitivity, 91·3%; specificity, 60·3%; c-statistic, 0·806), and 47·9% (sensitivity, 78·3%; specificity, 74·7%; c-statistic, 0·774), respectively. In multivariate analysis, all these parameters were independently associated with paroxysmal atrial fibrillation after adjusting for sex, age, diabetes mellitus, and previous stroke. Left atrial appendage volumetric analysis by real-time three-dimensional transesophageal echocardiography is a promising method for detecting paroxysmal atrial fibrillation in acute cerebral infarction or transient ischemic attack.

Slow Sinus Heart Rate as a Potential Predictive Factor of Paroxysmal Atrial Fibrillation in Stroke Patients

Background: Paroxysmal atrial fibrillation (PAF) is a strong independent risk factor for ischemic stroke and is also associated with stroke severity and mortality. However, the detection rate of PAF in patients with ischemic stroke is limited because they are often asymptomatic or present with sinus rhythm on electrocardiograms (ECGs). In the present study, we aimed to identify predictors of PAF in stroke patients by continuous ECG monitoring of the heart rate in sinus rhythm. Methods: We enrolled 741 consecutive patients with acute symptomatic ischemic stroke who were admitted to our hospital. Exclusion criteria were the following: (1) patients with persistent AF, (2) cardiac pacemaker users and (3) incomplete clinical investigations. Each patient was subject to 24-hour Holter ECG, cardiac monitoring by inpatient telemetry and routine transthoracic echocardiography. The minimum and mean sinus heart rates (SHRs) on 24-hour Holter ECGs were recorded. The presence of PAF was judged on the basis of previous history and cardiac studies during hospitalization. Clinical characteristics of the patients with and without PAF were compared, and multiple logistic regression analysis was performed to identify the predictors of PAF. Results: Of all enrolled patients, 606 (mean age 68.2 years, 63.4% male) were eligible for analysis, and the presence of PAF was confirmed in 116 subjects (19.1%). In the univariate analysis, the patients with and without PAF showed significant differences in age (74.3 vs. 66.7 years, p < 0.001), dyslipidemia (32.8 vs. 50.4%, p = 0.001), chronic heart failure (16.4 vs. 4.7%, p < 0.001), admission National Institute of Health Stroke Scale score (8.5 vs. 6, p < 0.001) and absence of vascular etiology (80.2 vs. 54.1%, p < 0.001). Furthermore, the minimum and mean SHRs were slower in the patients with than in those without PAF (46.5 vs. 54.0 bpm, p < 0.001 and 70.7 vs. 73.8 bpm, p = 0.009, respectively). In 501 (82.7%) out of 606 patients, minimum SHRs were detected at night (from 9:00 p.m. to 7:00 a.m.). A minimum SHR was an independent predictive factor of PAF in the multivariate analysis (odds ratio 1.08, 95% confidence interval 1.05 - 1.12, p < 0.001). Conclusions: A slow SHR on monitoring ECG is a potential predictive factor of PAF in patients with ischemic stroke.

N-Terminal Pro-Brain Natriuretic Peptide Shows Diagnostic Accuracy for Detecting Atrial Fibrillation in Cryptogenic Stroke Patients

Diagnosing paroxysmal atrial fibrillation in patients with stroke can be difficult. We aimed to determine if N-terminal pro-brain natriuretic peptide can help identify paroxysmal atrial fibrillation in cryptogenic stroke. Among 264 ischemic stroke patients, serum levels of N-terminal pro-brain natriuretic peptide were measured within 72 h of stroke onset. In cryptogenic stroke patients, 24-h Holter monitoring was used to look for paroxysmal atrial fibrillation within the first week and also three- and six-months after admission. First, patients with a defined etiology were used to construct a receiver operating characteristic curve for the diagnosis of atrial fibrillation. From this curve, the sensitivity and specificity of preestablished cutoff points for the diagnosis of atrial fibrillation were calculated. A logistic regression was performed to assess the independent relationship of the logarithm of N-terminal pro-brain natriuretic peptide levels with atrial fibrillation. The cutoff points were then evaluated in patients with cryptogenic stroke. One hundred eighty-four patients had a specific stroke etiology. Fifty-five patients had atrial fibrillation. Using multivariate analysis, the logarithm of N-terminal pro-brain natriuretic peptide levels was independently associated with atrial fibrillation. The area under the receiver operating characteristic curve of N-terminal pro-brain natriuretic peptide for the diagnosis of atrial fibrillation was 0.91 (95% confidence interval 0.87-0.95). The cutoff point of 265.5 pg/ml had a sensitivity of 100% and specificity of 70.5% for the diagnosis of atrial fibrillation. The cutoff point of 912 pg/ml had a sensitivity of 81.8% and a specificity of 87.5%. Eighty patients had a cryptogenic stroke. In 17, paroxysmal atrial fibrillation was found during follow-up. In these patients, the area under the curve for the diagnosis of paroxysmal atrial fibrillation was 0.83. The cutoff point of 265.5 had a sensitivity of 88.2% and a specificity of 61.9%. The cutoff point of 912 pg/ml had a sensitivity of 47.1% and a specificity of 88.9%. N-terminal pro-brain natriuretic peptide has good accuracy in predicting the presence of paroxysmal atrial fibrillation in patients with cryptogenic stroke and can help to identify these patients.

Abstract WP135: Sinus Bradycardia as a Potential Predictive Factor for Paroxysmal Atrial Fibrillation in Stroke Patients

Background and Purpose The detection rate of paroxysmal atrial fibrillation (PAF) in stroke patients is limited because they are often asymptomatic, or presenting sinus rhythm on ECG. To estimate the likelihood of PAF as a cause of ischemic stroke, we attempted to identify predictive factors for PAF using the data of sinus heart rate (SHR) on monitoring ECG. Methods We enrolled 711 consecutive patients admitted to our hospital with acute ischemic stroke. Exclusion criteria were (1) persistent AF; (2) cardiac pacemaker; and (3) incomplete clinical investigations. Minimum and mean SHR on 24-hour Holter ECG were obtained. The presence of PAF was judged based on previous history, initial ECG, 24-hour Holter ECG, and cardiac monitoring by inpatient telemetry. The clinical characteristics were compared between patients with and without PAF (PAF and non-PAF group, respectively), and multiple logistic regression analysis was performed to identify predictors for PAF. Results Of all enrolled patients, 577 patients were eligible for analysis, and PAF was confirmed in 110 (19.1%). Clinical parameters showing a significant difference between PAF and non-PAF groups included: age (mean, 74.1 vs. 66.6, P &lt;0.001); dyslipidemia (32.7% vs. 50.8%, P =0.001); lack of intra- or extracranial stenosis (54.0% vs. 79.1%, P &lt;0.001); chronic heart failure (17.3% vs. 4.9%, P &lt;0.001); and NIHSS score (median, 8 vs. 6, P =0.002). Minimum and mean SHR were lower in PAF group than in non-PAF group (46.4 vs. 54.1 bpm, P &lt;0.001; 71.0 vs. 73.8 bpm, P =0.021, respectively). Percentages of patients with PAF were highest in the lowest quartiles of minimum and mean SHR (Figure). Multivariate analysis showed minimum SHR as one of independent predictive factors of PAF (OR 1.08; 95% CI 1.05 to 1.12; P &lt;0.001). Conclusions Low SHR on monitoring ECG can be a novel predictive factor for PAF in ischemic stroke patients.

Abstract TP227: Three-dimensional Analysis Of Flow, Volume And Ejection Fraction Of The Left Atrial Appendage In Acute Stroke Patients With Paroxysmal Atrial Fibrillation

Background and objective: Decreased peak flow velocity (PFV) of the left atrial appendage (LAA) measured by transesophageal echocardiography (TEE) was reported to be associated with atrial fibrillation (AF) and thrombus formation in LAA. This study aimed to elucidate the association between flow, volume and ejection fraction (EF) of LAA measured by real-time three dimensional TEE (3D-TEE) and the presence of paroxysmal atrial fibrillation (PAF) in acute stroke. Methods: 3D-TEE was performed using an iE 33 Ultrasound Machine and X7-2t TEE transducer (Philips Healthcare) in acute stroke patients with sinus rhythm at the examination. Patients were divided into those with a history or later documentation of PAF (PAF group) and others (sinus group). PFV was measured by pulse Doppler and LAA volume was measured off-line using QLAB software. LAA volume was measured twice before p wave (maximum LAA volume) and after p wave (minimum LAA volume) to calculate EF of LAA. Results: Of a total 97 patients (26 women, 72.7±10.6 years), 20 were allocated to the PAF group and the remaining 77 to the sinus group. LAA volume and EF were correlated with PFV (r=0.378, p=0.0002 and r = 0.374, p=0.0002; respectively). Patients in the PAF group had lower PFV (39.0cm/s, 29.4-57.0 vs. 63.9cm/s, 38.3-81.8, p=0.0006), larger LAA volume (median 7.6ml, IQR 3.6-10.45 vs. 2.3ml, 1.6-6.2, p=0.0033) and lower EF (38.2%, 21.4-49.8 vs. 58.1%, 44.1-71.8, p=0.0006) than those in the sinus group. Using receiver operating characteristic curve analysis, the optimal cutoff of PFV to predict PAF patients was ≤39cm/s, with a sensitivity of 58%, a specificity of 89%, and a c-statistic of 0.756. The cutoff of LAA volume was ≥7.5ml, with a sensitivity of 55%, a specificity of 84%, and a c-statistic of 0.714. The cutoff of EF was ≤47.9%, with a sensitivity of 75%, a specificity of 75%, and a c-statistic of 0.751. Using the combination of LAA volume ≥7.5ml or EF ≤47.9%, patients with PAF were detected with a sensitivity of 85% and a specificity of 67%. Conclusions: Because EF of LAA was associated with FV, it is a promising marker of LAA function. LAA enlargement and reduced LAA contraction, measured by 3-dimensional techniques, in addition to lower FV may help us to detect those with PAF in acute stroke.

Evaluation of the impact of atrial fibrillation on rehospitalization events in heart failure patients in recent years

Although we have previously reported that the presence of paroxysmal atrial fibrillation (AF) is an independent risk factor for rehospitalization in patients with congestive heart failure (CHF) in a population from 1996 to 2002, the impact of AF configuration as a risk factor in a more recent population remains to be clarified. 319 patients with CHF admitted to our institute in 2006-2007 were retrospectively evaluated. The patients were divided into 3 groups in accordance with their basic cardiac rhythm, i.e. sinus rhythm (n=210), chronic AF (n=68), and paroxysmal AF (n=41). During the follow-up period of 19 ± 17 months, there was no significant difference in mortality or rehospitalization events among the 3 groups (p=0.542). In the multivariate analysis, no administration of β-blockers was the only independent risk factor for rehospitalization due to CHF exacerbation. The clinical impact of AF configuration as a risk factor of rehospitalization due to CHF exacerbation was considered to be decreased in recent years.