Incidence and prognostic significance of silent atrial fibrillation in acute myocardial infarction

Background

Silent atrial fibrillation (AF) has been suggested to be frequent after acute myocardial infarction (MI). Continuous ECG monitoring (CEM) has been shown to improve AF screening in patients at risk of stroke.

Objectives

We aimed to assess the incidence and prognosis of silent AF in patients with acute MI.

Methods

All the consecutive patients with acute MI were prospectively analyzed by CEM ≥ 48 h after admission. Silent AF was defined as asymptomatic episodes lasting at least 30 s. The population was divided into three groups: no-AF, silent AF and symptomatic AF.

Results

Among the 849 patients, 135 (16%) developed silent AF and 45 (5%) symptomatic AF. Compared with the no-AF group, patients with silent AF were markedly older (80 vs. 62 y, p < 0.001), more frequently women (43% vs. 30%, p = 0.006) and less likely to be smokers (20% vs. 36%, p < 0.001). They had impaired left ventricular ejection fraction (LVEF) and left atrial (LA) enlargement. By multivariate analysis, age, history of AF, indexed LA area and LVEF were identified as independent predictors of silent AF. In-hospital heart failure and death rates were markedly higher in silent AF group when compared with no-AF patients (41.8% vs 21.0% and 10.4% vs. 1.3%, respectively).

Conclusion

Our large prospective study showed for the first time that silent AF is more frequent than symptomatic AF after MI. Our work suggests that indexed LA area could help to predict the risk of developing silent AF. Moreover, the onset of silent AF is associated with worse hospital prognosis.     

A proposal for a new scoring system in the prediction of catheter ablation outcomes: Promising results from the Turkish Cryoablation Registry

Background

Although cryoballoon based catheter ablation is an effective therapeutic option in atrial fibrillation (AF), a significant amount of patients failed to remain in sinus rhythm at long term follow-up. Appropriate selection of patients for catheter ablation reduces unnecessary interventions and prevents complications related with catheter ablation. The purpose of our study is to propose a new scoring system in the prediction of recurrence after AF ablation with cryoballoon.

Method

A total of 236 patients (54% male, age 54.6 ± 10.45 years and 79.6% paroxysmal) with symptomatic AF underwent an index cryoablation. The first 3 months after AF ablation is defined as blanking period. Predictors of AF recurrence after cryoablation were analyzed with multivariate Cox regression analysis. BASE-AF₂ score [acronym stands for Body mass index > 28 kg/m² (1); Atrial dilatation > 40 mm (1); current Smoking (1); Early recurrence (1); duration of AF history > 6 years (1) and non-paroxysmal type (1) of AF] is identified by the total number of significant predictors of recurrence in each patient (range = 0–6).

Results

At median 20 (range: 12–30) months follow-up, 74.5% of the patients were free from AF recurrence. Of these patients, 64 (27.1%) patients had a BASE-AF₂ score of ≥ 3. Patients with AF recurrence had a higher mean BASE-AF₂ score (3.27 ± 0.82 vs. 1.1 ± 0.95, p < 0.001) compared to patients without AF recurrence. ROC analysis showed that a BASE-AF₂ score of ≥ 3 well predicted AF recurrence with a sensitivity of 80.8% and a specificity of 91.6% (AUC = 0.94; 95% CI: 0.89–0.97, p < 0.001). A BASE-AF₂ score of ≥ 3 was found to be an independent predictor of AF recurrence (HR: 3.34, 95% CI: 2.34–4.76, p = 0.001).

Conclusion

BASE-AF₂, which was identified as a new scoring system, has well predicted AF recurrence and could be helpful in selecting appropriate patients for interventional strategy.     

Maintenance of sinus rhythm after electrical cardioversion for recurrent atrial fibrillation following mitral valve surgery with or without associated radiofrequency ablation

Background

This study reports the outcomes of patients who underwent electrical cardioversion for atrial fibrillation recurrence following mitral valve surgery and associated radiofrequency ablation compared to those who did not undergo concomitant atrial fibrillation ablation.

Methods

The population consisted of 116 patients with persistent/long-standing persistent AF who underwent mitral valve surgery with (Group A, n = 54) or without (Group B, n = 62) associated radiofrequency ablation between January 2007 and January 2011 at three institutions and who subsequently underwent cardioversion for persistent atrial fibrillation within 12 months of their initial procedure.

Results

The mean follow-up duration was 30.7 ± 9.4 months. Of the 104 patients with acute restoration of SR 42 (40.3%) had AF recurrence. The average time to recurrence after cardioversion was 7.3 ± 4.2 days. Recurrence was significantly lower in patients undergoing ablation surgery (21.4%) than in those undergoing no ablation surgery (78.6%, p < 0.001). Non-performed ablation procedure (p < 0.001), time from surgery ≥ 88 days and left atrial dimensions ≥ 45.5 mm before cardioversion (both, p = 0.005) were multivariable predictors of atrial fibrillation recurrence. In Group B the use of amiodarone was inversely correlated with recurrence of AF (p < 0.001). This correlation was not significant (r = − 0.02, p = 0.85) in Group A.

Conclusions

Electrical cardioversion for recurrent AF showed better results and stable recovery of sinus rhythm in patients undergoing concomitant surgical ablation during mitral valve surgery. This might be attributable to substrate modification caused by surgical lesions. Amiodarone improved the ECV-success rate only in patients with no associate ablation. Further larger randomized studies are necessary to confirm our findings.     

Left atrial size and function as predictors of new-onset of atrial fibrillation in patients with asymptomatic aortic stenosis: The simvastatin and ezetimibe in aortic stenosis study

Background

Left atrial (LA) size and function change with chronically increased left ventricular (LV) filling pressures. It remains unclear whether these variations in LA parameters can predict new-onset atrial fibrillation (AF) in asymptomatic patients with aortic stenosis (AS).

Methods

Data were obtained in asymptomatic patients with mild-to-moderate AS (2.5 ≤ transaortic Doppler velocity ≤ 4.0 m/s), preserved LV ejection fraction (EF), no previous AF, and were enrolled in the Simvastatin and Ezetimibe in Aortic Stenosis study. Peak-aortic velocity, LA_max volume & LA_min volume were measured by echocardiography. LA conduit (LA_con) volume was defined as LV stroke volume − LA stroke volume. LA function was expressed as LA-EF (LA_max − LA_min volume/LA_max).

Results

In the 1159 patients included, new-onset AF occurred in 71 patients (6.1%) within a mean follow-up of 4.2 ± 0.9 years. Mean age was 66 ± 9.7 years, aortic valve area index 0.6 ± 0.2 cm²/m², LV mass 99.2 ± 29.7 g/m², LA_max volume 34.6 ± 12.0 mL/m², LA_min volume 17.9 ± 9.3 mL/m², LA-EF 50 ± 15% and LA_con volume 45 ± 21 mL/m². Baseline LA_min volume predicted new-onset AF in Cox multivariable analysis (HR:2.3 [95%CI:1.3–4.4], P < 0.01), and added prognostic information on AF development beyond conventional risk factors (likelihood ratio, P < 0.01). In comparison of c-indexes LA_min volume was superior to all other LA measurements. Net reclassification index improved by 15.9% when adding LA_min volume to a model with classic risk factors for AF (P = 0.01).

Conclusion

LA_min volume independently predicted new-onset AF in patients with asymptomatic AS and was superior to LA-EF, LA_con and LA_max volumes and conventional risk factors.     

Validation of contemporary stroke and bleeding risk stratification scores in non-anticoagulated Chinese patients with atrial fibrillation

Background

Risk stratification schemes assessing stroke and thromboembolism (stroke/TE) and bleeding relating to atrial fibrillation (AF) have largely been derived and validated in Western populations. We assessed risk factors that constitute scores for assessing stroke/TE (CHADS₂, CHA₂DS₂-VASc) and bleeding (HAS-BLED), and the predictive value of these scores in a large cohort of Chinese patients with AF.

Methods and results

We studied 1034 AF patients (27.1% female, median age 75; 85.6% non-anticoagulated) with mean follow-up of 1.9 years. On multivariate analysis, vascular disease was independently associated with stroke/TE in non-anticoagulated patients (p = 0.04). In patients with a CHADS₂ or CHA₂DS₂-VASc score = 1, the rate of stroke/TE was 2.9% and 0.9% respectively, but in patients at “high risk” (scores ≥ 2), this rate was 4.6% and 4.5%, respectively. The c-statistics for predicting stroke/TE with CHADS₂ and CHA₂DS₂-VASc were 0.58 (p = 0.109) and 0.72 (p < 0.001), respectively. Compared to CHADS₂, the use of CHA₂DS₂-VASc would result in a Net Reclassification Improvement (NRI) of 16.6% (p = 0.009) and an Integrated Discrimination Improvement (IDI) of 1.1% (p = 0.002). Cumulative survival of the patients with a CHA₂DS₂-VASc score ≥ 2 was decreased compared to those with a CHA₂DS₂-VASc score 0–1 (p < 0.001), but the CHADS₂ was not predictive of mortality. There was an increased risk of major bleeding with increasing HAS-BLED score (c-statistic 0.61, 95% CI: 0.51–0.71, p = 0.042).

Conclusions

Vascular disease was a strong independent predictor of stroke/TE in Chinese patients with AF. The CHA₂DS₂-VASc score performed better than CHADS₂ in predicting stroke/TE in this Chinese AF population. Cumulative survival of the patients at high risk with the CHA₂DS₂-VASc score (but not using CHADS₂) was significantly decreased.     

Predictors of new onset atrial fibrillation in patients with heart failure

Introduction

Stroke associated with atrial fibrillation (AF) is more frequent in heart failure. It is unknown what variables predict future AF in these patients and how AF might evolve over time. We investigated this in patients with implantable cardiac defibrillators (ICD) where AF detection is optimal.

Methods

Single centre, retrospective, observational cohort study. All ischaemic cardiomyopathy patients with dual chamber, primary prevention ICD implants between Aug 2003 and Dec 2009 were screened and included if at implant, they had no known AF history. Nine variables were analysed. AF was defined as any atrial tachyarrhythmia ≥ 180 bpm and ≥ 30 s. Multivariable, binary logistic regression models were built by adding variables significant in the univariate models. Variables were retained in the final multivariate models if p < 0.05.

Results

n = 197 met the inclusion criteria (85.8% male, median age: 66.8 years). After median follow-up for 2.8 years, 44.2% developed AF. After univariate analysis, the baseline variables associated with AF after implant were age, NYHA class and renal impairment (RI, defined eGFR < 60 ml/min/1.73 m²) (p < 0.05). After multivariable analysis, the only variable which was associated with AF was RI (HR: 2.04 (CI: 1.10–3.79)). Two baseline variables were independently associated with all-cause mortality: RI (HR: 2.42 (1.14–5.12)) and non-white ethnicity.

Conclusion

RI at time of implant was independently associated with both future AF and all-cause mortality during long-term follow-up. RI was a stronger predictor of AF than age. Those patients with heart failure and RI should be regularly screened for asymptomatic AF, regardless of age, to ensure that stroke prophylaxis may be initiated.     

Influence of left ventricular remodeling on atrial fibrillation recurrence and cardiovascular hospitalizations in patients undergoing rhythm-control therapy

Background

Atrial fibrillation (AF) patients with left ventricular hypertrophy (LVH) and diastolic dysfunction may derive benefit from being in sinus rhythm but no data are available to support this strategy in them. We sought to investigate effect of left ventricular remodeling on cardiovascular outcomes in AF patients undergoing rhythm control strategy.

Methods

We identified 1088 patients with echocardiographic data on left ventricular mass (LVM) enrolled in the AFFIRM trial. Using the American Society of Echocardiography (ASE) criteria, patients were divided into 4 categories: 1) normal geometry, 2) concentric remodeling, 3) eccentric hypertrophy, and 4) concentric hypertrophy. The primary endpoint was AF recurrence and the secondary endpoint was cardiovascular hospitalization (CVH).

Results

In rhythm control arm, median time to recurrence in patients with concentric LVH was 13.3 months (95% CI 8.2–24.5) vs. 28.3 months (95% CI 20.2–48.6) in patients without LVH. Concentric left ventricular hypertrophy (LVH) was independently predictive of AF recurrence (HR 1.49, 95% CI 1.10–2.01, p = 0.01) in rhythm control arm, but not in overall population or rate control arm. Both concentric and eccentric LVH were independently predictive of cardiovascular hospitalization (CVH) in the overall population, with respective HRs of 1.36 (1.04–1.78, p = 0.03) and 1.38 (1.02–1.85, p = 0.04).

Conclusion

Concentric LVH is predictive of AF recurrences when a predominantly pharmacologic rhythm-control strategy is employed. Different patterns of LVH seem to be important determinants of outcomes (AF recurrence and CVH). These findings may have important clinical implications for the management of patients with AF and LVH. Further studies are warranted to confirm our findings.     

Short stature and ischemic stroke in nonvalvular atrial fibrillation: New insight into the old observation

Background

For decades, repeated epidemiologic observations have been made regarding the inverse relationship between stature and cardiovascular disease, including stroke. However, the concept has not been fully evaluated in patients with atrial fibrillation (AF). We investigated whether patient’s height is associated with ischemic stroke in patients with nonvalvular AF and attempted to ascertain a potential mechanism.

Methods

All 558 AF patients were enrolled: 211 patients with ischemic stroke (144 men, 68 ± 10 years) and 347 no-stroke patients (275 men, 56 ± 11 years) as a control group. Clinical characteristics and echocardiographic parameters were compared between the two groups.

Results

(1) Stroke patients were shorter than those in the control group (164 ± 8, vs. 169 ± 8 cm, p < 0.001). However, body mass index failed to predict ischemic stroke; (2) Short stature (OR 0.93, 95% CI 0.91– 0.95, p < 0.001) along with left atrial (LA) anterior-posterior diameter and diastolic mitral inflow velocity (E) to diastolic mitral annuls velocity (E’) (E/E’) were independent predictor of stroke; (3) Height showed inverse correlation with E/E’ independently, even after adjusting for other variables, including age, sex, and body weight, and comorbidities β − 0.20, p = 0.003); (4) LA size showed no correlation with stature (R = − 0.06, p = 0.18), whereas left ventricular size increases according to height of patients.

Conclusions

Short stature is associated with occurrence of ischemic stroke and diastolic dysfunction in patients with AF and preserved systolic function. Height is a non-modifiable risk factor of stroke and might be more important than obesity in Asian AF patients, who are relatively thinner than western populations.     

Prognostic value of plasma von Willebrand factor and its cleaving protease ADAMTS13 in patients with atrial fibrillation

Background

The von Willebrand factor (vWF) is essential for platelet adhesion and arterial thrombosis. It is degraded into less active multimers by ADAMTS13. Patients with atrial fibrillation (AF) exhibit higher plasma vWF and lower ADAMTS13 antigen levels. The vWF/ADAMTS13-ratio might help to estimate the pro-thrombotic risk of patients with AF. We therefore investigated whether a high ratio of vWF/ADAMTS13, independently of clinical risk scores, predicts major adverse cardiovascular events (MACE) in patients with AF.

Methods

This prospective longitudinal single center study included 269 patients with AF. Blood samples were analyzed for vWF and ADAMTS13-antigen concentration by means of enzyme-linked immunoassay kits.

Results

After adjustment for all univariable predictors for MACE (p ≤ 0.1), ADAMTS13 ≤ 49.77% (HR 1.833 (95% CI 1.089–3.086); p = 0.023) and vWF/ADAMTS13-ratio > 27.57 (HR 2.174 (95% CI 1.238–3.817); p = 0.007) remained independently associated with outcome. vWF > 1434.92 mU/ml (HR 1.539 (95% CI 0.883–2.682); p = 0.128) alone failed to independently predict MACE. In patients with low and intermediate risk for MACE according to the CHADS₂-score the addition of high vWF/ADAMTS13-ratio levels (> 27.57) had significant impact on the patients' outcome.

Conclusion

A high ratio of vWF/ADAMTS13 independently predicts MACE in patients with AF. Therefore, vWF and its cleaving protease ADAMTS13 might play an important role in the development and perpetuation of vascular disease in AF patients. This might be a novel target for future treatment strategies or an additional help for risk stratification in AF patients.     

Differences in catheter ablation of paroxysmal atrial fibrillation between males and females

Background

Catheter ablation (CA) has become a standard treatment for patients with atrial fibrillation (AF). However, gender-related differences associated with CA of paroxysmal AF (PAF) remain unclear.

Methods

We compared 1124 consecutive patients (mean age, 61 ± 10 years; male, n = 864) with PAF scheduled for CA between the genders.

Results

Females were significantly older (p < 0.0001), and had a lower body-mass-index (p = 0.02), smaller left atrial dimension (LAD; p = 0.04), larger LAD indexed by the body-surface-area (LADI; p < 0.0001) and better left ventricular ejection fraction (p < 0.0001) at baseline. Ischemic heart disease (p = 0.007) was more frequent in males, whereas hypertrophic cardiomyopathy (p = 0.007) and mitral stenosis (p = 0.001) were more frequent in females. More additional procedures were performed to eliminate non-pulmonary vein foci in females than males (p < 0.05), but those locations were similar between the genders. The incidence of procedure-related complications was similar between genders (p = 0.73). Sinus rhythm was similarly maintained between females and males after the first CA (56.4% vs. 59.3% at 5 years, p = 0.24), but was significantly lower in females after the last CA (76.5% vs. 81.3% at 5 years, p = 0.007). More females did refuse multiple CA procedures (especially a second one) than males (37.8% in females vs. 27.4% in males, p = 0.02). The age (HR, 0.98/y, p = 0.01), duration of AF (HR, 1.04/y, p = 0.0001), number of failed anti-arrhythmic-drugs (HR, 1.10, p = 0.03) and LADI (HR, 1.89 per 10 mm/m², p = 0.001) were significantly associated with AF-recurrence in males, but not in females.

Conclusions

Specific differences and similarities between the genders were observed in PAF patients undergoing CA.     

Left ventricular geometry and outcomes in patients with atrial fibrillation: The AFFIRM Trial

Background

Echocardiographically determined left ventricular hypertrophy (LVH) is a marker of cardiovascular disease related to prognosis and clinical outcomes. We sought to determine if LVH is a measure of outcomes in atrial fibrillation (AF) patients.

Methods

We performed a post-hoc analysis of patients with echocardiographic data enrolled in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) Trial. Patients were stratified based on gender-adjusted echocardiography derived interventricular septal (IVS) thickness, relative wall thickness (RWT), gender-adjusted LV mass, and type of LV remodeling (normal LV geometry, concentric hypertrophy, eccentric hypertrophy, and concentric remodeling).

Results

Of 4060 patients in AFFIRM, echocardiographic data were available in 2433 patients (60%). Multivariate analysis revealed that LVH defined as moderately or severely abnormal IVS thickness was an independent predictor of both all cause mortality (HR 1.46, 95%CI 1.14–1.86, p = 0.003) and stroke (HR 1.89, 95%CI 1.17–3.08, p = 0.01). This association was confirmed when IVS thickness was assessed as continuous or categorical variable. Concentric LV hypertrophy was associated with the highest rates of all cause mortality (HR 1.53; 95%CI 1.11–2.12; p = 0.009).

Conclusion

An easily obtained echocardiographic index of LVH (IVS thickness) may enhance risk stratification of patients with AF, and raise the possibility that LVH regression should be a therapeutic target in this population.     

Prevalence and predictors of worsened left ventricular diastolic dysfunction after catheter ablation of atrial fibrillation

Background

The interactions between atrial fibrillation (AF) and left ventricular diastolic dysfunction (LVDD) are complex and not well defined. Despite the high prevalence of LVDD in the AF population, therapies for LVDD remain limited. Previous studies have suggested that restoration of sinus rhythm with catheter ablation has a positive effect on LVDD, but the prevalence and predictors for worsened LVDD are unknown.

Methods

70 consecutive patients included in prospective AF catheter ablation registry (61 ± 10 years, 66% male) with paroxysmal (n = 40) or persistent AF (n = 30) were examined by transthoracic echocardiography, before and 12 months after ablation. LVDD was classified according to current guidelines. Rhythm outcome of the ablation was verified by serial 7-day Holter ECG.

Results

LVDD was present in 27 patients (38%) at baseline and in 33 patients (47%) at 12 months follow-up (p = .327). An improvement of LVDD was observed in 13 patients (19%), an aggravation was found in 19 (27%), while it was unchanged in the remaining 38 patients (54%). In uni- and multivariable regression analysis, total ablation time (OR 1.611 per 10 min ablation time, 95% CI 1.088 – 2.386, p = .017) was associated with LVDD progression, while neither baseline characteristics nor rhythm during follow-up influenced LVDD alterations. There was no association between echocardiographic deterioration and symptoms.

Conclusions

Catheter ablation of AF can worsen LVDD in a substantial proportion of patients with more aggressive ablation leading to aggravation of LVDD. While there are no apparent negative short-term effects, long-term consequences need to be determined.     

Analysis of oxidative stress expressed by urinary level of 8-hydroxy-2′-deoxyguanosine and biopyrrin in atrial fibrillation: Effect of sinus rhythm restoration

Background

Oxidative stress is considered to contribute to the pathological consequences of atrial fibrillation (AF). We examined the level of oxidative stress in AF patients and changes in its level following sinus rhythm restoration.

Methods

Oxidative stress level was evaluated by urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, and urinary biopyrrin, an oxidative metabolite of bilirubin. In Study 1, we compared 8-OHdG/creatinine levels between patients with permanent AF (AF-group, n = 40) and sinus rhythm (SR-group, n = 133). In Study 2, we examined the changes in 8-OHdG and biopyrrin levels in 36 patients with persistent AF following sinus rhythm restoration by electrical or pharmacological cardioversion (n = 15) and radiofrequency catheter ablation (n = 21).

Results

In Study 1, 8-OHdG/creatinine levels were significantly higher in AF-group than in SR-group (19.1 ± 8.6 vs. 12.3 ± 5.5 ng/mg, p < 0.001). Multivariate analysis showed that the presence of AF was an independent factor that significantly correlated with 8-OHdG/creatinine level after adjustment for other covariates to oxidative stress (β = 0.36, p < 0.001). Sinus rhythm was maintained at the chronic phase in patients of all Study 2 (7.2 ± 5.8 months after cardioversion or catheter ablation). 8-OHdG/creatinine and biopyrrin/creatinine levels at the chronic phase were significantly lower than those before cardioversion or catheter ablation (8.7 ± 3.2 vs. 21.7 ± 15.1 ng/mg, p < 0.0001 and 1.7 ± 1.1 vs. 3.0 ± 1.9 mU/mg, p < 0.0001).

Conclusions

Oxidative stress level is significantly increased in AF patients, but can be improved by restoration of sinus rhythm. The results suggest that the pathogenic process of AF is promoted by AF itself through the production of oxidative stress.     

Post-shock sinus node recovery time is an independent predictor of recurrence after catheter ablation of longstanding persistent atrial fibrillation

Background

Electro-anatomical remodeling of the atria has been reported to be associated with sinus node dysfunction in patients with atrial fibrillation (AF). We hypothesized that post-shock sinus node recovery time (PS-SNRT: the time from cardioversion to the earliest sinus node activation) is related to the degree of left atrial (LA) remodeling and the clinical outcome of radiofrequency catheter ablation (RFCA) in patients with longstanding persistent AF (L-PeAF).

Methods and results

We included 117 patients with L-PeAF (82.0% males, 55.4 ± 10.7 years old) who underwent RFCA. PS-SNRTs were measured after internal cardioversion (serial shocks 2, 3, 5, 7, 10, and 15 J) before RFCA. All patients underwent the same ablation design, and we compared regional LA volume (3D-CT imaging) and LA voltage (NavX). Results: 1. During the 13.5 ± 5.8-month follow-up period, it was noted that the patients with recurrent AF 3 months after RFCA (n = 31) had longer PS-SNRTs (1622.90 ± 1196.92 ms vs. 1112.53 ± 690.68 ms, p = 0.005) and greater anterior LA volume (p = 0.032) than those who remained in sinus rhythm. 2. The patients with PS-SNRT ≥ 1100 ms showed lower AF-free rates (58.3%) compared to those with PS-SNRT < 1100 ms (89.5%, p < 0.001). However, shock energy, number of cardioversion, and LA volume were not different between two groups. 3. Multivariate Cox regression analysis demonstrated PS-SNRT ≥ 1100 ms was a significant predictor of clinical recurrence of AF (HR 5.426, 95% CI 2.099–14.028, p < 0.001).

Conclusion

In patients with L-PeAF, prolonged PS-SNRT is an independent predictor of clinical recurrence of AF after RFCA, but not closely associated with electro-anatomical remodeling of LA.     

Risk factors and incidence of stroke and MACE in Chinese atrial fibrillation patients presenting to emergency departments: A national wide database analysis

Background

Contemporary clinical risk stratification schemata for predicting stroke and thromboembolism in patients with atrial fibrillation (AF) are largely derived from western cohorts. The purpose of the present study is to assess the potential risk factors for stroke and major adverse cardiac events (MACE) in a large population of Chinese AF patients presenting to emergency department.

Methods

The Chinese AF registry is a multicenter, prospective, observational study with 1 year follow up. Patients who presented to an emergency department with atrial fibrillation or atrial flutter were recruited from November 2008 to October 2011. The MACE included all cause mortality, stroke, non-central nervous system systemic embolism and major bleed.

Results

A total of 2016 AF patients (1104 women) were included in the final analysis. Multivariate Cox regression analysis showed that the risk factors for stroke were female gender (1.419 (1.003–2.008), p = 0.048), age ≥ 75 (2.576 (1.111–4.268), p < 0.001), previous stroke/TIA (2.039 (1.415–2.939), p < 0.001), LVSD (1.700 (1.015–2.848), p = 0.044) and previous major bleeding (2.481 (1.141–5.397), p = 0.022). For MACE, age ≥ 75 (3.042 (2.274–4.071), p < 0.001), heart failure (1.371 (1.088–1.728), p = 0.008), previous stroke/TIA (1.560 (1.244–1.957), p < 0.001), LVSD (1.424 (1.089–1.862), p = 0.010) and COPD (1.393 (1.080–1.798), p = 0.011) were independent risk factors. History of hypertension and diabetes was not associated with the events, neither stroke nor MACE. For non-anticoagulation patients, the c-statistic for predicting stroke was 0.685 (0.637–0.732) and for MACE was 0.717 (0.687–0.746), respectively.

Conclusions

We demonstrated that, except for the traditional risk factors, clinicians should pay more attention to patients with prior major bleeding or COPD in Chinese AF patients presenting to emergency department.     

Adherence to guidelines and mortality in atrial fibrillation

Objective

Determining the adherence to ACC/AHA/ESC 2006 guidelines and its influence on the survival of patients with atrial fibrillation.

Methods

Prospective observational study of patients discharged during 2007 from an Internal Medicine department with a main or secondary diagnose of atrial fibrillation. The stroke risk was estimated with the CHADS₂ score. The follow-up was carried out in outpatient medical office or via telephone.

Results

We included 259 patients (mean age 80.9 years); 73% of them had a high risk of stroke. Oral anticoagulants were administered to 134 (51.7%), and antiplatelet drugs to 71 (27%) patients. A rate control strategy was chosen for 155 (59.8%) patients and a rhythm control one for 28 (10.8%). In 100 (38.6%) patients, treatment was adherent to the guidelines. Adherence to the guidelines was associated with age (0.95 95%CI 0.92–0.99; p = 0.03), contraindication to the use of oral anticoagulants (0.38 95%CI 0.18–0.81; p = 0.01) and mitral valve heart disease/valvular prosthesis (2.10 95%CI 1.04–4.25; p = 0.04). The median follow-up was 727 days, and 191 patients died. Patients treated according to the guidelines had a higher rate of survival during the first three years (0.47 vs. 0.36; p = 0.049). The use of oral anticoagulants was associated with a higher probability of survival over a 5 year period (0.34 vs 0.21; p = 0.001) and the rate control strategy during the first year (0.69 vs 0.57; p = 0.04).

Conclusions

In the real world, the treatment of atrial fibrillation according to the guidelines is associated with improved survival for up to three years during follow-up.     

The association of asthma and atrial fibrillation — A nationwide population-based nested case–control study

Background

Asthma and atrial fibrillation (AF) have been reported to be related to an increased risk of cardiovascular events. However, the relationship between asthma and AF has not been fully elucidated. The purpose of this study was to examine the association between asthma and AF risk.

Methods

We conducted a population-based nested case–control study including a total of 7439 newly-diagnosed adult patients with AF and 10,075 age-, gender-, comorbidity-, and cohort entry date-matched subjects without AF from the Taiwan National Health Insurance database. Exposure to asthma as well as medications including bronchodilators and corticosteroid before the index date was evaluated to investigate the association between AF and asthma as well as concurrent medications.

Results

AF patients were 1.2 times (adjusted OR 1.2, 95% CI 1.109–1.298) more likely to be associated with a future occurrence of asthma independent of comorbidities and treatment with corticosteroids and bronchodilator. In addition, the risks of new-onset AF were significantly higher among current users of inhaled corticosteroid, oral corticosteroids, and bronchodilators. Newly users (within 6 months) have the highest risk (inhaled corticosteroid: OR, 2.13; 95% CI, 1.226–3.701, P = 0.007; oral corticosteroid: OR, 1.932; 95% CI, 1.66–2.25, P < 0.001; non-steroid bronchodilator: OR, 2.849; 95% CI, 2.48–3.273, P < 0.001). A graded association with AF risk was also observed among subjects treated with corticosteroid (inhaled and systemic administration) and bronchodilators. New users (within 6 months) of these medications had the highest risk of AF (ICS: OR, 2.13; 95% CI, 1.226–3.701, P = 0.007; oral corticosteroid: OR, 1.932; 95% CI, 1.66–2.25, P < 0.001; non-steroid bronchodilator: OR, 2.849; 95% CI, 2.48–3.273, P < 0.001). A graded association with AF risk was also observed among subjects treated with ICS or bronchodilator.

Conclusions

Asthma was associated with an increased risk of developing future AF.     

Don't move during ablation of atrial fibrillation!

Background

Restless patient is recalcitrant during ablation of atrial fibrillation (AF). We aimed to assess the association between patient movements during AF ablation and its outcome.

Methods

We examined the body movement during AF ablation in 78 patients with the use of a novel portable respiratory monitor, the SD-101, which also has the ability to quantify the frequency of body movements.

Results

The body movement index, defined as the number of the units of time with body movement events divided by the recording time (11.4 ± 6.5 events/h), was significantly correlated with the ablation time defined as the time from the first point of the ablation to the end of the procedure (1.2 ± 0.3 h) (r = 0.35; p = 0.0014) and a total radiofrequency energy applied (56.6 ± 17.7 kW) (r = 0.36; p = 0.0015). A multiple linear regression analysis showed that non-paroxysmal AF (β = 0.25; p = 0.036) and the body movement index (β = 0.36; p = 0.0019) were independent determinants of the ablation time. The body movement index was similar in patients with and without recurrence of AF.

Conclusions

Keeping patients motionless may be important to reduce the procedural duration of AF ablation.     

Incidence,predictors and prognostic value of serious hemorrhagic complications following transcatheter aortic valve implantation

Background

TAVI is an alternative solution for patients with aortic valve stenosis (AS) who are refused for conventional surgery. We sought to evaluate the incidence, characteristics, predictors and prognosis impact of serious hemorrhagic complications following transcatheter aortic valve implantation (TAVI).

Methods

One hundred and seventy one consecutive patients with symptomatic severe AS (83.5 ± 6.1 y; 53% women; mean EuroSCORE = 22.1 ± 12.3) underwent transapical (TA) or transfemoral (TF) TAVI in our institution using Edwards SAPIEN© and Medtronic CoreValve© devices. The primary evaluated criterion was the incidence of any bleeding complication, according to the Valve Academic Research Consortium (VARC) criteria.

Results

VARC serious hemorrhagic complications occurred in 34.5% of patients (n = 23 life-threatening/disabling (LT/D) and n = 36 major bleedings). Most of these complications were related to access site complications (69%). Multivariable analysis revealed that TA access, low weight and underlying coronary artery diseases were independent predictors for development of serious bleeding. The mortality was significantly higher in patients with serious events compared to patients without bleeding (p = 0.008, log-rank analysis). Although the survival didn't significantly differ in patients with major hemorrhagic events, subjects with LT/D bleeding events had a higher mortality than the subjects with no hemorrhagic complications (p < 0.001, log-rank analysis). Occurrence of VARC LT/D event independently predicted all-cause mortality (HR = 5.35 [2.51–11.43], p < 0.001) during the first year following TAVI in multivariate Cox regression analysis.

Conclusion

Severe bleeding is frequent following TAVI procedure and is mainly related to local hemorrhage. VARC LT/D events are associated with decreased survival after AS correction.     

Renal disease and left atrial remodeling predict atrial fibrillation in patients with cardiovascular risk factors

Objectives

In this prospective population-based study, we tested the possible interaction between chronic kidney disease (CKD) and left atrium volume index (LAVI) in predicting incident atrial fibrillation (AF).

Methods

We enrolled 3549 Caucasian subjects, 1829 men and 1720 women, aged 60.7 ± 10.6 years, without baseline AF and thyroid disorders. Echocardiographic left ventricular mass and LAVI were measured. Renal function was calculated by estimated glomerular filtration rate (e-GFR). To test the effect of some clinical confounders on incident AF, we constructed different models including clinical and laboratory parameters. AF diagnosis was made by standard electrocardiogram or 24-h ECG-Holter, hospital discharge diagnoses, and by the all-clinical documentation.

Results

During the follow-up (53.3 ± 18.1 months), 546 subjects developed AF (4.5 events/100 patient-years). Progressors to AF were older, had a higher body mass index, blood pressure, LDL-cholesterol, glucose, cardiac mass, and LAVI, and had lower e-GFR. Hypertension, metabolic syndrome, diabetes, cardiac hypertrophy and CKD were more common among AF cases than controls. In the final Cox regression model, variables that remained significantly associated with AF were: cardiac hypertrophy (HR = 1.495, 95% CI = 1.215–1.841), renal disease (HR = 1.528, 95% CI = 1.261–1.851), age (HR = 1.586, 95% CI = 1.461–1.725) and LAVI (HR = 2.920, 95% CI = 2.426–3.515). The interaction analysis demonstrated a synergic effect between CKD and cardiac hypertrophy (HR = 4.040, 95% CI = 2.661–6.133), as well as between CKD and LAVI (HR = 4.875, 95% CI = 2.699–8.805). The coexistence of all three subclinical organ damages significantly increases the arrhythmic risk (HR = 7.185, 95% CI = 5.041–10.240).

Conclusions

Our data demonstrate that LAVI and CKD significantly interact in a synergic manner in increasing AF risk.