Search

Introduction: The predictive value of left atrial volume (LAV) in atrial fibrillation (AF) is known, but the relationship of right atrial volume (RAV) and biatrial volume (BAV) with AF recurrence after pulmonary vein isolation (PVI) is not clear. Cardiac magnetic resonance (CMR) imaging allows us to more precisely quantify atrial volume. We investigated LAV, RAV, and BAV as predictors of AF recurrence following PVI in AF patients., Methods and Results: We assessed 100 AF patients (age = 59.8 ± 9.5 years, 74 males, 26 females) who underwent nonenhanced CMR before their first PVI. LAV and RAV were measured using CMR. All patients were in sinus rhythm during CMR. BAV was calculated as the sum of LAV and RAV. During the 8-month follow-up, AF recurrence occurred in 23 patients. LAV, RAV, and BAV were significantly greater in patients with AF recurrence than in those without (LAV, 103.7 ± 25.8 vs 81.8 ± 24.2 mL, P < 0.001; RAV, 109.4 ± 27.0 vs 82.2 ± 19.6 mL, P < 0.001; BAV, 213.1 ± 46.7 vs 164.1 ± 38.7 mL, P < 0.001). Multivariate logistic regression analysis revealed that increased LAV, RAV, and BAV were significantly correlated with AF recurrence. The area under the receiver operation characteristic curve for BAV showed the largest value compared to that of LAV or RAV alone., Conclusions: LAV, RAV, and BAV were independent predictors of AF recurrence after PVI. Quantifying BAV may additionally improve prognostic stratification compared with LAV or RAV., (© 2018 Wiley Periodicals, Inc.)

Background: The proportion of patients with atrial fibrillation (AF) treated with anticoagulation varies from country to country. In Japan, little is known about regional differences in frequency of warfarin use or prognosis among patients with non-valvular AF (NVAF)., Methods and results: In J-RHYTHM Registry, the number of patients recruited from each of 10 geographic regions of Japan was based on region population density. A total of 7,406 NVAF patients were followed up prospectively for 2 years. At baseline, significant differences in various clinical characteristics including age, sex, type of AF, comorbidity, and CHADS2score, were detected among the regions. The highest mean CHADS2score was recorded in Shikoku. Frequency of warfarin use differed between the regions (P<0.001), with lower frequencies observed in Hokkaido and Shikoku. Baseline prothrombin time international normalized ratio differed slightly but significantly between the regions (P<0.05). On univariate analysis, frequency of thromboembolic events differed among the regions (P<0.001), with the highest rate seen in Shikoku. An inverse correlation was detected between frequency of thromboembolic and of major hemorrhagic events (P=0.062). On multivariate analysis, region emerged as an independent risk for thromboembolism., Conclusions: Thromboembolic risk, frequency of warfarin use, and intensity and quality of warfarin treatment differed significantly between geographic regions of Japan. Region was found to be an independent predictor of thromboembolic events. (Circ J 2016; 80: 1548-1555).

Introduction: Using a high-pitch dual-source CT (DSCT), we aimed to quantify the amounts of contrast media, radiation doses, and image qualities in patients undergoing pulmonary vein (PV) isolation., Methods and Results: The study enrolled 60 patients who were randomly assigned in a 1: 1: 1 ratio to undergo ECG-gated 64-slice multidetector computed tomography (MDCT; group I, n = 20), ECG-gated 128-DSCT (group II, n = 20), and nongated 128-DSCT (group III, n = 20). The total amount of contrast media was lower in groups II and III compared with group I (I: 54.7 ± 5.6, II: 26.6 ± 2.7, and III: 28.7 ± 6.9 mL, P < 0.001). The CT dose index was lower in groups II and III compared with group I (I: 73.1 ± 5.2, II: 3.5 ± 0.1, and III: 3.7 ± 0.1 mGy, P < 0.001). The dose length product was lower in groups II and III compared with group I (I: 1154.8 ± 82.8, II: 75.4 ± 2.3, and III: 77.2 ± 1.9 mGy × cm, P < 0.001). The total CT effective radiation dose was lower in groups II and III compared with group I (I: 16.2 ± 1.2, II: 1.1 ± 0.1, and III: 1.1 ± 0.1 mSv, P < 0.001). The total CT scan duration was shorter in group III compared with groups I and II (I: 30.8 ± 2.2, II: 23.4 ± 3.6, and III: 16.0 ± 2.4 minutes, P < 0.001). There were no significant differences in quality for integrated electroanatomical mapping (EAM) and parameters associated with PV isolation among the 3 groups., Conclusion: Nongated 128-DSCT provides sufficient image quality to allow integrated EAM while exposing the patient to less contrast media, lower radiation doses, and shorter CT scan durations., (© 2015 Wiley Periodicals, Inc.)

Introduction: Recently, direct-acting oral anticoagulants (DOACs) have been introduced, with increasing use in patients with non-valvular atrial fibrillation (NVAF). However, warfarin continues to be widely used and the benefits and risks of warfarin in NVAF patients warrant closer inspection., Materials and Methods: Thromboembolism, major hemorrhage, and total and cardiovascular mortalities were analyzed in 7,406 NVAF patients in the J-RHYTHM Registry from January to July 2009, prior to DOAC introduction. Propensity score matching analysis was performed to reduce the differences in clinical characteristics between non-anticoagulant (n=1002) and warfarin (n=6404) cohorts to reassess warfarin outcomes over 2years., Results: The incidence of thromboembolism was significantly greater in the non-anticoagulant cohort (3.0%) than in the warfarin cohort (1.5%, P<0.001) with less frequent major hemorrhage in the non-anticoagulant cohort (0.8%) than in the warfarin cohort (2.1%, P=0.009). Using propensity score matching, new subsets (n=896 each) were obtained, with matching of the clinical characteristics between warfarin and non-anticoagulant subsets. The warfarin subset had lower risk factors compared with the total warfarin cohort. The incidence of thromboembolism was higher in the non-anticoagulant subset (2.9%) than in the warfarin subset (0.7%, P<0.001). However, major hemorrhage was not significantly different between the two subsets., Conclusions: Although warfarin was associated with a significantly higher incidence of hemorrhage in the unmatched cohorts, propensity score matching revealed that warfarin reduced thromboembolism without a significant increase in hemorrhage in the matched subsets with lower risks. Propensity score matching reduced selection bias and provided rational comparisons although it had indwelling limitations., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: The difference between left atrial (LA) and systemic coagulation activity in paroxysmal atrial fibrillation (PAF) is unclear., Methods and Results: We enrolled 100 patients with PAF who underwent AF ablation. Warfarin was stopped 1 day before the procedure. LA volume index and LA emptying fraction were measured by 64-slice multidetector computed tomography. Immediately after transseptal puncture, blood samples were simultaneously collected from the LA and systemic circulation (SC). In addition, to evaluate the effect of warfarin on D-dimer levels we recruited an additional 27 PAF patients on continuous warfarin. Even in patients with low CHADS2 scores (mean 0.59 ± 0.68) and during sinus rhythm, the prevalence of positive LA-D-dimer (≥ 0.5 µg/ml) was greater than that of SC-D-dimer (23% vs. 10%, P<0.01). The LA-D-dimer-positive patients had a larger mean LA volume index and reduced LA emptying fraction than the LA-D-dimer-negative patients. Multiple logistic regression analysis revealed that LA volume index was independently correlated with positive LA-D-dimer (odds ratio 2.245, 95% confidence interval 1.194-4.626, P=0.0112). The prevalence of positive LA-D-dimer was significantly lower in patients taking continuous warfarin, than in those on discontinuous warfarin (3.7% vs. 23%, P=0.025)., Conclusions: An enlarged LA volume index was associated with high LA coagulation status in patients with paroxysmal AF. Adequate warfarin control during AF catheter ablation may reduce the prevalence of positive LA-D-dimer.

To evaluate left atrial appendage (LAA) dysfunction using left atrial pulse-wave tissue Doppler imaging (PW-TDI) in acute cerebral embolism (ACE) patients with sinus rhythm (SR), transthoracic (TTE) and transesophageal echocardiograhy (TEE) were performed in 60 consecutive patients with SR without obvious left ventricular dysfunction within 2 weeks after ACE. Two groups were identified: LAA dysfunction [LAA emptying peak flow velocity (LAA-eV) <0.55 m/s, n = 20, age 65 ± 10 years] and without LAA dysfunction (LAA-eV ≥ 0.55 m/s, n = 40, age 64 ± 10 years) on TEE. Left atrial wall motion velocity (WMV) was obtained from PW-TDI, with the sample volume placed at the left atrial anterior wall adjacent to ascending aortic inferior wall from the long axis view on TTE. WMVs showed triphasic waves: after the P wave (La') during systole (Ls'), and during early diastole. La' and Ls' were significantly lower in the group with versus without LAA dysfunction (4.9 ± 1.4 vs. 7.7 ± 1.8 cm/s, p < 0.0001; 5.3 ± 2.0 vs. 6.7 ± 1.9 cm/s, p < 0.001, respectively) and prevalence of paroxysmal atrial fibrillation, left atrial volume index, and serum levels of brain natriuretic peptide were significantly higher (60 vs. 15 %, p < 0.001; 32 ± 13 vs. 24 ± 13 ml/m(2), p < 0.05; 174 ± 279 vs. 48 ± 68 pg/ml, p < 0.01, respectively). La' was an independent predictor of LAA dysfunction (OR 0.380, 95 % CI 0.156-0.925, p < 0.05), and was significantly correlated with LAA-eV (r = 0.594, p < 0.0001) and LAA fractional area change (r = 0.682, p < 0.0001). The optimal cut-off value for LAA-eV < 0.55 m/s was 5.5 cm/s (sensitivity 83 %, specificity 88 %). La' is a useful and convenient strong predictor of LAA dysfunction in ACE patients with SR.

Treatment guidelines for atrial fibrillation (AF) used in Western countries describe female gender as a risk factor for thromboembolic events in patients with nonvalvular AF (NVAF). The present study aimed to determine the impact of gender on prognosis of Japanese patients with NVAF. A subanalysis of 7,406 patients with NVAF (mean age 70 years) who were followed-up prospectively for 2 years was performed using data from the J-RHYTHM registry. The primary end points were thromboembolic events, major hemorrhaging, total mortality, and cardiovascular mortality. Compared with male subjects (n = 5,241), female subjects (n = 2,165) were older and displayed greater prevalences of paroxysmal AF, heart failure, and hypertension but less prevalences of diabetes, previous cerebral infarction, and coronary artery disease. Male and female patients had mean CHADS2 (Congestive heart failure, Hypertension, Age of 75 years or more, Diabetes mellitus and prior Stroke or transient ischemic attack) scores of 1.6 and 1.8, respectively (p <0.001). Warfarin was given to 87% of male patients and 86% of female patients (p = 0.760), and the 2 genders displayed similar mean international normalized ratio of prothrombin time values at baseline (1.91 vs 1.90, respectively, p = 0.756). Multivariate logistic regression analysis indicated that male gender was an independent risk factor for major hemorrhaging (odds ratio 1.59, 95% confidence interval 1.05 to 2.40, p = 0.027) and all-cause mortality (odds ratio 1.78, 95% confidence interval 1.25 to 2.55, p <0.002) but not for thromboembolic events (odds ratio 1.24, 95% confidence interval 0.83 to 1.86, p = 0.297) or cardiovascular mortality (odds ratio 0.96, 95% confidence interval 0.56 to 1.66, p = 0.893). In conclusion, female gender is not a risk factor for thromboembolic events among Japanese patients with NVAF who were treated mostly with warfarin. However, male gender is a risk factor for major hemorrhaging and all-cause mortality., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Low-grade inflammation associated with heart failure (HF) is known to deteriorate cardioembolic stroke in patients with atrial fibrillation (AF). Little is known about the relationship between atrial endothelial impairment induced by innate immunity and thrombus formation. We examined whether atrial endothelial impairment through Toll-like receptor (TLR) 4 signaling causes atrial thrombogenesis. TLR4, heat shock protein 60, and vascular cell adhesion molecule (VCAM)-1 expression were higher in the atrium of AF patients who underwent valve replacement surgery with HF compared with those without it (p < 0.05). We created thoracic transverse aortic constriction (TAC) in TLR4 knock-out (KO) and wild-type (WT) mice. Atrial thrombosis was observed less frequently in TLR4 KO mice (4/15) than in WT mice (16/20) 4 weeks after TAC despite similar severity of heart failure. The decrease in endothelial nitric oxide synthase (eNOS) phosphorylation and increase in VCAM-1 and plasminogen activator inhibitor (PAI)-1 expression, observed in the atrium of WT mice following TAC, were significantly attenuated in TLR4 KO mice (p < 0.05). Nuclear factor-κB (NF-κB) activation after TAC was attenuated in TLR4 KO mice compared with WT mice. Activation of mitogen-activated protein kinase p38 (p38) after TAC was also attenuated in TLR4 KO mice (p < 0.05). Thus, increased VCAM-1 and PAI-1, and decreased eNOS phosphorylation through the TLR4/NFκB/p38 pathway, may be associated with atrial thrombogenesis in the heart failure mice model. Atrial endothelial impairment through the TLR4 signaling may play a role in atrial thrombogenesis in AF patients with HF.

Objective: The aim of the present study was to examine the relationship between myocardial damage caused by atrial fibrillation (AF) and subsequent cardiovascular events in AF patients with chronic heart failure (CHF)., Methods and Results: We measured the serum levels of heart-type fatty acid binding protein (H-FABP) and high-sensitivity troponin T in 402 consecutive CHF patients with chronic AF (CHF-AF, n=201) or sinus rhythm (CHF-SR, n=201). The patients with CHF-AF had higher H-FABP and troponin T levels than those with CHF-SR. In order to examine the prognostic value of myocardial damage markers in CHF-AF and CHF-SR patients, we followed the above patients and analyzed their clinical outcomes. A multivariate Cox proportional hazard analysis revealed that both the serum H-FABP and troponin T levels independently predicted subsequent cardiovascular events. A Kaplan-Meier analysis demonstrated that the rate of cardiovascular events was higher in the patients with elevated H-FABP and troponin T levels. The optimal cut-off values for the myocardial damage markers of cardiovascular events were higher in the CHF-AF patients than in the CHF-SR patients (H-FABP, 5.4 vs. 4.6 ng/mL and troponin T, 0.030 vs. 0.013 ng/mL)., Conclusion: Myocardial damage advances in association with the presence of AF and is associated with subsequent cardiovascular events in both CHF-AF and CHF-SR patients. In this study, the cut-off values for the myocardial damage markers were higher in the CHF-AF patients than in the CHF-SR patients.

Background: Target anticoagulation levels for warfarin in Japanese patients with non-valvular atrial fibrillation (NVAF) are unclear., Methods and Results: Of 7,527 patients with NVAF, 1,002 did not receive warfarin (non-warfarin group), and the remaining patients receiving warfarin were divided into 5 groups based on their baseline international normalized ratio (INR) of prothrombin time (≤1.59, 1.6-1.99, 2.0-2.59, 2.6-2.99, and ≥3.0). Patients were followed-up prospectively for 2 years. Primary endpoints were thromboembolic events (cerebral infarction, transient ischemic attack, and systemic embolism), and major hemorrhage requiring hospital admission. During the follow-up period, thromboembolic events occurred in 3.0% of non-warfarin group, but at lower frequencies in the warfarin groups (2.0, 1.3, 1.5, 0.6, and 1.8%/2 years for INR values of ≤1.59, 1.6-1.99, 2.0-2.59, 2.6-2.99, and ≥3.0, respectively; P=0.0059). Major hemorrhage occurred more frequently in warfarin groups (1.5, 1.8, 2.4, 3.3, and 4.1% for INR values ≤1.59, 1.6-1.99, 2.0-2.59, 2.6-2.99, and ≥3.0, respectively; P=0.0041) than in non-warfarin group (0.8%/2 years). These trends were maintained when the analyses were confined to patients aged ≥70 years., Conclusions: An INR of 1.6-2.6 is safe and effective at preventing thromboembolic events in patients with NVAF, particularly patients aged ≥70 years. An INR of 2.6-2.99 is also effective, but associated with a slightly increased risk in major hemorrhage. (UMIN Clinical Trials Registry UMIN000001569)

Background: It is important to evaluate left atrial appendage (LAA) dysfunction for primary and secondary prevention of stroke in patients with atrial fibrillation (AF). LAA dysfunction can reportedly be evaluated by LAA wall velocity (LAWV) measured by transthoracic echocardiographic (TTE) imaging. The aim of this study was to examine whether TTE-LAWV can predict long-term cerebrovascular events in patients with ischemic stroke with AF., Methods: TTE imaging and transesophageal echocardiographic imaging were performed <7 days after onset in 179 consecutive patients with stroke with AF. TTE-LAWV was measured using Doppler tissue imaging at the LAA tip from the parasternal short-axis view on TTE imaging, as previously reported. All patients were followed up prospectively., Results: Cerebrovascular events were defined as cerebrovascular death and/or recurrent ischemic stroke requiring hospitalization. There were 32 cerebrovascular events during a median follow-up period of 397 days. TTE-LAWV was significantly lower in patients with cerebrovascular events than in patients without (8.3 ± 2.8 vs 11.3 ± 4.0 cm/sec, P < .01). Cox multivariate hazard analysis showed that low TTE-LAWV (<8.7 cm/sec) was an independent predictor of cerebrovascular events (hazard ratio, 3.460; P < .05). Kaplan-Meier analysis showed that cerebrovascular event rates were significantly higher in patients with low TTE-LAWV (<8.7 cm/sec) compared with those with high TTE-LAWV (34% vs 7%, P < .01)., Conclusions: Impaired LAA function was associated with long-term cerebrovascular events in patients with stroke with AF. TTE-LAWV may be a feasible parameter for risk stratification in patients with AF., (Copyright © 2012 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Background: The aim of this study was to compare the long-term procedural outcomes, the stability of atrioventricular conduction, and the new onset of atrial fibrillation (AF), after ablation of atrioventricular nodal reentrant tachycardia (AVNRT)., Methods and Results: Consecutive patients with AVNRT (n=109), who underwent slow-pathway ablation, were divided into two groups based on the median age of the studied patients: the younger group aged <55 years and the older group aged ≥55 years. During a mean follow-up period of 60.6 months, the rate of change in the PR interval from before ablation to follow-up was significantly greater in older patients compared with younger patients. However, there was no delayed-onset high-degree AV block during follow-up in either group. No patients in the younger group suffered from persistent AF, whereas persistent AF occurred in 5/54 (9.3%) older patients. Multivariate Cox analysis revealed that atrial vulnerability, with induction of AF during the electrophysiological study, was the only predictor of the development of AF (Hazard ratio: 13.9, 95% confidence interval: 1.62-119.2, p<0.01)., Conclusion: Slow-pathway ablation of AVNRT is a reliable strategy even in older patients. However, physicians should consider regular long-term follow-up of older patients with atrial vulnerability, in order to assess the subsequent development of AF.

Background: Chronic pulmonary disorders, such as chronic obstructive pulmonary disease (COPD) and fibrosing lung diseases, and atrial fibrillation (AF), are prevalent in elderly people. The impact of cardiac co-morbidities in the elderly, where pulmonary function is impaired, cannot be ignored as they influence mortality. The relationship between the prevalence of AF and pulmonary function is unclear. The aim of this study was to evaluate this relationship in participants in a health check., Methods: Subjects aged 40 or older (n = 2,917) who participated in a community-based annual health check in Takahata, Japan, from 2004 through to 2005, were enrolled in the study. We performed blood pressure measurements, blood sampling, electrocardiograms, and spirometry on these subjects., Results: The mean FEV(1) % predicted and FVC % predicted in AF subjects was significantly lower than in non-AF subjects. The prevalence of AF was higher in those subjects with airflow limitation or lung restriction than in those without. Furthermore, AF prevalence was higher in those subjects with severe airflow obstruction (FEV(1) %predicted < 50) than in those who had mild or moderate airflow obstruction (FEV(1) %predicted ≥ 50), although there was no difference between the prevalence of AF in subjects with 70≤ FVC %predicted <80 lung restriction and those with FVC %predicted <70. Multiple logistic regression analysis revealed that FEV(1) %predicted and FVC %predicted are independent risk factors for AF (independent of age, gender, left ventricular hypertrophy, and serum levels of B-type natriuretic peptide)., Conclusion: Impaired pulmonary function is an independent risk factor for AF in the Japanese general population.

Background: Atrial fibrillation is associated with ischemic stroke because of thrombi that form within the left atrial appendage (LAA). The aim of this study was to develop a new parameter for LAA function that is easily performed using transthoracic echocardiography (TTE)., Methods: TTE and transesophageal echocardiography were performed in 106 patients with stroke. LAA wall motion velocity (TTE-LAWV) was measured using Doppler tissue imaging at the LAA tip., Results: TTE-LAWV was significantly lower in patients with atrial fibrillation and LAA thrombus than in those with atrial fibrillation and no LAA thrombus and in sinus rhythm (7.5 +/- 1.9 vs 10.0 +/- 3.4 and 13.8 +/- 5.7 cm/s, respectively, P < .05). TTE-LAWV was significantly correlated with LAA emptying flow velocity (R = 0.462, P < .05). The multivariate logistic regression analysis showed that TTE-LAWV < 8.7 cm/s was an independent predictor of LAA thrombus formation (odds ratio, 9.473; 95% confidence interval, 1.172-76.55; P < .05)., Conclusion: TTE-LAWV can noninvasively evaluate LAA dysfunction and assist in the detection of LAA thrombus., (2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Background: The mortality and morbidity rates of various cardiovascular diseases differ between Western countries and Japan. The age- and gender-specific prevalence rate of atrial fibrillation (AF) in the general population of Japan was determined using the data from periodic health examinations in 2003., Methods: Data of 630,138 subjects aged 40 years or more (47% were men and 34% were employees of companies and local governments) were collected from northern to southern Japan. The prevalence of diagnosed AF in each 10-year age group of both men and women was determined. Based on these prevalence rates and the Registry of Residents, the number of people having AF in Japan was estimated., Results: The prevalence rate of AF increased as both male and female subjects aged, and it was 4.4% for men but only 2.2% for women aged 80 years or more (p<0.0001). As a whole, the AF prevalence of men was three times that of women (1.35 versus 0.43%, p<0.0001). There may be approximately 716,000 people (95% confidence interval (CI), 711,000-720,000) with AF in Japan, an overall prevalence of 0.56%. The number of people having AF was projected to be 1.034 (95% CI, 1.029-1.039) million, an overall prevalence of 1.09%, in 2050., Conclusions: The prevalence of AF increased in Japan as the population aged, as in Western countries. The overall prevalence of AF in Japan is approximately two-thirds of that in the USA. The projected increase in the number of people having AF is modest in Japan in 2050.

Background: Our previous study showed that diacylglycerol kinase zeta (DGKzeta), which degenerates diacylglycerol (DAG), inhibits ventricular structural remodeling and rescues activated G protein (alpha)q (G(alpha)q)-induced heart failure. However, whether DGKzeta inhibits atrial remodeling is still unknown., Objective: This study aimed to elucidate the effects of DGKzeta on atrial remodeling., Methods: A transgenic mouse (G(alpha)q-TG) with cardiac expression of activated G(alpha)q and a double transgenic mouse (G(alpha)q/DGKzeta-TG) with cardiac overexpression of DGKzeta and activated G(alpha)q were created., Results: During electrocardiogram (ECG) recording for 10 min, atrial fibrillation was observed in 5 of 11 anesthetized G(alpha)q-TG mice but not in any wild-type (WT) and G(alpha)q/DGKzeta-TG mice (P <.05). All of the ECG parameters measured were prolonged in the G(alpha)q-TG compared with WT mice. Interestingly, in G(alpha)q/DGKzeta-TG mice, although the PR and RR intervals were still prolonged, the P interval, QRS complex, and QT interval were not different from those in WT mice. In Langendorff-perfused hearts, the incidence of atrial tachyarrhythmia induced by rapid atrial pacing was greater in G(alpha)q-TG hearts than in G(alpha)q/DGKzeta-TG hearts (P <.05). Action potential duration prolongation and impulse conduction slowing were observed in G(alpha)q-TG atria compared with G(alpha)q/DGKzeta-TG atria. Dilatation of the left atrium with thrombus formation was observed in 9 G(alpha)q-TG hearts but not in any G(alpha)q/DGKzeta-TG hearts. Moreover, the degree of extensive interstitial fibrosis in the left atrium was greater in G(alpha)q-TG hearts than that in G(alpha)q/DGKzeta-TG hearts (P <.05)., Conclusion: These results show that DGKzeta inhibits G(alpha)q-induced atrial remodeling and suggest that DGKzeta is a novel therapeutic target for atrial fibrillation.

The left atrial appendage (LAA) is 1 of the common thromboembolic sources in patients with atrial fibrillation (AF) with stroke. The aim of this study was to examine the usefulness of LAA opacification seen on contrast echocardiography for predicting stroke recurrence in patients with AF. In 192 patients with stroke with AF who underwent transesophageal echocardiography within 7 days after the onset, intracardiac intensity variation at the orifice of the LAA just after intravenous infusion of Levovist (1,500 mg) was measured. During a mean follow-up of 450 days, the association between LAA intensity variation and recurrence of cerebrovascular events was assessed. LAA intensity variation was markedly lower in 19 patients with stroke recurrence than 173 patients without stroke recurrence (8.1 +/- 4.7 vs 12.1 +/- 5.1 dB; p <0.001). LAA thrombus-negative patients with low LAA intensity variation (< or =9.2 dB; n = 45) had higher cerebrovascular recurrent event rates than those with high LAA intensity variation (>9.2 dB; n = 109; 20.0% vs 3.7%; p <0.001) and thrombus-positive patients (15.8%). Cox multivariate hazard analysis showed that of routine echocardiographic parameters, decreased LAA intensity variation was the only independent predictor of stroke recurrence (hazard ratio 5.244, p <0.01). In conclusion, LAA intensity variation on contrast transesophageal echocardiography is a new sensitive index for LAA flow stagnation and recurrent cerebrovascular events in patients with AF with stroke.

Partial atrial standstill is characterized by the failure of atrial activity either spontaneously or in response to electrical stimulation in restricted site of atria. In this case with bradycardia, atrial standstill was restricted to the lateral and posterior right atrium. The markedly prolonged intraatrial conduction delay was observed in the superior to septal region of the right atrium. The electroanatomical mapping was successfully utilized to estimate atrial activity and to find a suitable site for atrial lead placement. The electroanatomical mapping may become an innovated strategy to estimate atrial electrical status in partial atrial standstill.

It has been poorly understood whether inflammation may contribute to atrial structural remodeling and increase the propensity for atrial fibrillation (AF) to persist. We investigated the relationship between C-reactive protein (CRP) elevation and the development of atrial remodeling in AF. The study population comprised 50 consecutive paroxysmal AF (PAF) patients and 50 control patients without AF. All patients underwent echocardiography, and high-sensitivity CRP was routinely measured. C-Reactive protein was significantly higher in the patients with PAF than control patients (0.231+/-0.176 mg/dl vs 0.055+/-0.041 mg/dl, P<0.001). Other predictors of elevated CRP included left ventricular mass (P<0.05), left ventricular end-systolic diameter (P<0.05), and left atrial (LA) diameter (P<0.001). In a multivariate analysis, only CRP and LA diameter were independent predictors of PAF. Elevated CRP levels correlated with LA diameter (r=0.489, P<0.001). Left atrial diameter was increased in PAF patients compared with control patients (P<0.001). We found that a longer duration of AF is associated with higher CRP levels and a larger LA diameter (duration <30 days: CRP 0.166+/-0.139 mg/dl, LA diameter 38.4+/-8.0 mm; duration >30 days: CRP 0.345+/-0.181 mg/dl, LA diameter 45.6+/-6.6 mm; P<0.001). In conclusion, longer AF duration is associated with CRP elevation and atrial structural remodeling, as approximated by larger LA diameter. However, CRP elevation, while correlating with LA diameter, was not an independent predictor of atrial structural remodeling. Thus, it remains unclear whether CRP and the inflammatory state are contributory to LA remodeling or whether LA remodeling or AF induces elevation in CRP and inflammation.

Brugada syndrome is characterized by J wave and ST-segment elevation of right precordial leads and causes idiopathic ventricular fibrillation. We experienced a patient of Brugada syndrome with prominent J wave and ST-segment elevation not only in V(1) to V(3) but also in many leads. He suffered spontaneous ventricular fibrillation and resuscitated by direct current. He has no structural heart disease.

Objective: The goal of this study was to investigate transesophageal echocardiographic (TEE) findings after the termination of atrial fibrillation to clarify the direct evidence for occurrence of acute cardiogenic brain embolism (CBE) in patients with paroxysmal atrial fibrillation (PAF)., Patients and Methods: Among 98 consecutive patients with CBE, we investigated TEE in 16 patients with PAF (Group CBE, 72 +/- 10 years) within 7 days of the onset and 2 weeks after the first study, in comparison with 15 age-matched PAF patients without CBE (Group N). The duration from reversal to normal sinus rhythm to first TEE was 6 +/- 1 days in both groups., Results: There were no significant differences in left atrial dimension and emptying flow velocity of the left atrial appendage (LAA-eV) between groups. Group CBE had significantly larger LAA area (4.3 +/- 1.3 cm2 vs. 3.1 +/- 1.0 cm2, p < 0.05), smaller LAA fractional area change (LAA-FAC) (43 +/- 25% vs. 80 +/- 22%, p < 0.001), and a higher incidence of left atrial spontaneous echo contrast (LAA-SEC) (25% vs. 7%, p < 0.05) than group N, and those abnormalities in group CBE were significantly improved at the second TEE (LAA area: to 3.2 +/- 0.9 cm2, p < 0.05; LAA-FAC: to 84 +/- 26%, p < 0.001; LAA-SEC: to 0%, p < 0.05), respectively., Conclusion: LAA-FAC is a more sensitive marker for LAA dysfunction than the widely used index, LAA-eV, and a sustained deterioration of LAA-FAC may be direct evidence for thrombus formation and occurrence of acute CBE in patients with PAF.