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Spiller R - - 2008
BACKGROUND: The human gut harbours a complex community of bacteria whose relationship with their host is normally mutually beneficial. Recent studies suggest a disturbance of this relationship in irritable bowel syndrome (IBS) and the potential to correct this using prebiotics and probiotics. AIM: To review the mechanisms of action of ...
Meineri Massimiliano - - 2008
Introduction: Atrial fibrillation (AF) occurs in 20-30% of patients undergoing coronary revasularization surgery and is associated with significant perioperative morbidity and mortality.[1-2] During coronary artery bypass graft surgery (CABG), left ventricular (LV) diastolic dysfunction (DD) is a frequent occurrence.[3] The echocardiographic preditors of perioperative DD are not well defined. This ...
Amar David - - 2008
Although bradyarrhythmias or malignant ventricular tachyarrhythmias have been reported in less than 1% of patients following noncardiac surgery, rapid atrial arrhythmias more frequently affect the elderly who undergo thoracic operations. This article focuses on new issues leading to the improved understanding of the pathophysiology and mechanisms of postoperative atrial arrhythmias. ...
Macchia Alejandro - - 2008
PURPOSE: Current strategies for avoiding atrial fibrillation (AF) are of limited value. We aim to assess the relationship between omega-3 fatty acids (n-3 PUFA) and AF occurrence in post-myocardial infarction (MI) patients. METHODS: A population study, linking hospital discharge records, prescription databases, and vital statistics, was conducted and included all ...
Serra José Luis - - 2008
Atrial Fibrillation (AF) is one of the most frequent arrhythmias, especially in elderly patients. Cardiac overload increases the incidence of AF. Clinical presentation of atrial fibrillation can occur as nonsustained paroxysms, persistent episodes and in chronic-permanent form. The physio-pathological mechanisms are: *Circuit of multiple and anarchic re-entries *Atrial fibrillatory conduction ...
Amir Offer - - 2008
We analyzed the possible association between aldosterone synthase (CYP11B2) T-344C polymorphism, which is associated with increased aldosterone activity, and the prevalence of atrial fibrillation (AF) in 196 consecutive patients who had symptomatic systolic heart failure (HF; left ventricular ejection fraction <40%) for > or =3 months before recruitment. Genomic DNA ...
Takahashi Kazuhiro - - 2008
The mechanisms responsible for atrial fibrillation (AF) in post-operative Fontan patients are unclear, and the role of catheter ablation for treating AF is not well defined. We present a case of an 18-year-old woman who experienced drug-resistant paroxysmal AF late after the Fontan operation. We eliminated the AF by the ...
Luria David M - - 2008
Flutter Ablation and Subsequent Arrhythmia. INTRODUCTION: Patients with atrial flutter (AFL) treated medically are at high risk for subsequent development of atrial fibrillation (AF). Whether curative radiofrequency ablation of AFL can modify the natural history of arrhythmia progression is not clear. We aimed to determine whether ablation of AFL decreases ...
Bunch T Jared - - 2008
BACKGROUND: Hypertrophic cardiomyopathy (HCM) is often accompanied by atrial fibrillation (AF) due to diastolic dysfunction, elevated left atrial pressure, and enlargement. Although catheter ablation for drug-refractory AF is an effective treatment, the efficacy in HCM remains to be established. METHODS: Thirty-three consecutive patients (25 male, age 51 +/- 11 years) ...
Tang Ri Bo - - 2008
BACKGROUND AND OBJECTIVE: Recent advances in multi-slice computed tomography (MSCT) have allowed an improved analysis of left atrial (LA) and left atrial appendage (LAA) anatomy prior to catheter ablation of atrial fibrillation (AF). However, data regarding the ability of MSCT to identify LA/LAA thrombus are limited. This prospective study compared ...
Porter Michael - - 2008
INTRODUCTION: Complex fractionated atrial electrograms (CFAE) may identify critical sites for perpetuation of atrial fibrillation (AF) and provide useful targets for ablation. Current assessment of CFAE is subjective; automated detection algorithms may improve reproducibility, but their utility in guiding ablation has not been tested. METHODS AND RESULTS: In 67 patients ...
Segerson Nathan M - - 2008
INTRODUCTION: Several noninvasive measures of cardiac risk such as heart rate variability (HRV) cannot be used in patients with atrial fibrillation (AF). One promising exception is the measure of ventricular cycle length entropy (VCLE) where initial data suggest that a reduction in VCLE portends an increased risk of cardiac death ...
Yoshida Kentaro - - 2008
BACKGROUND: The mechanistic and clinical significance of complex fractionated atrial electrograms (CFAE) in the coronary sinus (CS) has been unclear. METHODS AND RESULTS: Antral pulmonary vein isolation (APVI) was performed in 77 patients with paroxysmal (32) or persistent AF (45). CS electrograms recorded for 60 seconds before and after APVI ...
Lin C-S - - 2008
Electrical, contractile and structural remodeling have been characterized in atrial fibrillation (AF), and the latter is considered to be the major contributor to AF persistence. Recent data show that interstitial fibrosis can predispose to atrial conduction impairment and AF induction. The interplay between cardiac matrix metalloproteinases (MMPs) and their endogenous ...
Speer Gábor - - 2008
BACKGROUND: Osteoprotegerin (OPG) is a marker and regulator of arterial calcification, and it is related to cardiovascular survival in haemodialysis patients. The link between OPG and aortic stiffening--a consequence of arterial calcification--has not been previously evaluated in this population, and it is not known whether OPG-related mortality risk is mediated ...
Byrne Melissa - - 2008
BACKGROUND: Atrial fibrillation (AF) is a common comorbidity in heart failure (HF) patients and is classically associated with acceleration in the rate of HF progression. The precise mechanism for this interaction is unclear, but comprises "bidirectional" aspects in which AF promotes HF and HF also increases the likelihood of AF. ...
Ogawa Hideyuki - - 2008
BACKGROUND: Several preliminary studies have indicated that atrial pacing can prevent atrial tachyarrhythmias. The suggested mechanisms by which pacing may be effective include suppression of premature atrial beats. METHODS AND RESULTS: The Atrial Pacing Preference (APP; Guidant, St Paul, MN, USA) algorithm allows the pacemaker to maintain a pacing rate ...
Abhayaratna Walter P - - 2008
The aim of this prospective study was to evaluate the incremental value of left atrial (LA) function for the prediction of risk for first atrial fibrillation (AF) or atrial flutter. Maximum and minimum LA volumes were quantitated by echocardiography in 574 adults (mean age 74 +/- 6 years, 52% men) ...
Wylie John V JV - - 2009
Inducibility of atrial fibrillation (AF) with burst pacing after pulmonary vein (PV) isolation is associated with recurrent AF. This study evaluated whether an external 30 Joule (J) shock synchronized to the R wave, during the vulnerable period of atrial repolarization, is able to risk-stratify patients further for AF recurrence after ...
Lin Jiaxiong - - 2008
BACKGROUND: The mechanism(s) underlying atrial fibrillation (AF) initiation along the ligament of Marshall (LOM) remains controversial. OBJECTIVES: We sought to examine the role of the autonomic nervous system in arrhythmogenesis along the LOM. METHODS: In 31 anesthetized dogs, a left thoracotomy exposed the LOM. During atrial pacing, high-frequency stimulation (HFS: ...
Dinanian Sylvie - - 2008
AIMS: A decrease in L-type calcium current (ICaL) is an important mechanism favouring atrial fibrillation (AF). Here, we aimed to identify pathogenic factors associated with ICaL downregulation. METHODS AND RESULTS: Atrial myocytes were isolated from right atrial appendages obtained from 86 adult patients in sinus rhythm with coronary artery disease, ...
Weinberg Kenneth M - - 2008
BACKGROUND: There are no universally accepted ECG diagnostic criteria for atrial flutter (AFL), making its differentiation from "coarse" atrial fibrillation (AF) difficult. METHODS: To develop diagnostic criteria for AFL, we examined two sets of ECGs. Set 1 consisted of 100 ECGs (50 AF, AFL) with diagnoses confirmed by intracardiac recordings. ...
Kanagaratnam Prapa - - 2008
BACKGROUND: Atrial fibrillation (AF) is characterized by irregular atrial activation maintained by an arrhythmogenic substrate. We addressed the hypothesis that the substrate of human AF includes changes in atrial conduction properties. METHODS: Patients in sinus rhythm (SR) and permanent AF undergoing cardiac surgery underwent right atrial epicardial mapping. AF was ...
Galaska Rafal - - 2008
BACKGROUND: In recent years the WTMM (wavelet transform modulus maxima) and MDFA (multifractal detrended fluctuation analysis) methods have become widely used techniques for the determination of nonlinear, multifractal heart rate (HR) dynamics. The purpose of our study was to compare multifractal parameters of heart rate calculated using both methods in ...
Tada Hiroshi - - 2008
BACKGROUND: Complex fractionated atrial electrograms (CFAEs) may play a role in the genesis of atrial fibrillation (AF). One type of CFAE is continuous electrical activity (CEA). The prevalence and characteristics of CEA in patients with paroxysmal and persistent AF are unclear. METHODS AND RESULTS: In 44 patients (age = 59 ...
Sra Jasbir - - 2008
Atrial fibrillation (AF) is a common arrhythmia. Although significant work still needs to be done, recent advances in understanding the mechanisms of AF have led to the development of elegant catheter mapping techniques for ablation of AF, complemented by the evolution of various imaging and navigational technologies. Due to the ...
Roux Jean-François - - 2008
BACKGROUND: Targeting of complex fractionated electrograms (CFEs) has been described as an approach for catheter ablation of atrial fibrillation (AF); however, the distribution and temporal stability of CFE regions remain poorly defined. METHODS: In patients with persistent AF referred for ablation, we performed two consecutive left atrial (LA) CFE maps ...
Cohen Marc - - 2008
Atrial fibrillation (AF) is a progressive disease in which arrhythmia-induced remodeling facilitates evolution from paroxysmal AF to persistent and permanent AF. Changes in electrical, structural, and contractile properties of cardiac tissue that are thought to underlie AF maintenance and progression are reviewed. Also examined is the negative impact of AF ...
Mountantonakis Stavros Emmanouil - - 2008
Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and a predictor of all-cause mortality. Subclinical hyperthyroidism is an independent risk factor for developing AF but its clinical significance in younger patients has not been established. We describe a clinical case of a 44-year-old female with newly diagnosed ...
Buck Sandra - - 2008
AIMS: Cardiac resynchronization therapy (CRT) is an established therapy for patients with heart failure and sinus rhythm (SR), but its value in atrial fibrillation (AF) remains unclear. Furthermore, response to CRT may be difficult to predict in these patients. The aim of our study was to investigate whether predictors for ...
Epolito William J - - 2008
The effect of operational conditions and initial dye concentration on the reductive transformation (decolorization) of the textile dye Reactive Blue 4 (RB4) using zero-valent iron (ZVI) filings was evaluated in batch assays. The decolorization rate increased with decreasing pH and increasing temperature, mixing intensity, and addition of salt (100gL(-1) NaCl) ...
Takahashi Yoshihide - - 2008
OBJECTIVES: This study sought to determine the characteristics of atrial electrograms predictive of slowing or termination of atrial fibrillation (AF) during ablation of chronic AF. BACKGROUND: There is growing recognition of a role for electrogram-based ablation. METHODS: Forty consecutive patients (34 male, 59 +/- 10 years) undergoing ablation for chronic ...
Lopes R D - - 2008
OBJECTIVE: To assess variables associated with the occurrence of atrial fibrillation (AF) and the relation of AF with short- and long-term outcomes and with other in-hospital complications in patients with acute coronary syndromes (ACS) with and without ST-segment elevation. DESIGN: Pooled database of 120 566 patients with ST-segment elevation myocardial ...
Fung Jeffrey W H - - 2008
BACKGROUND: Left atrial (LA) volume is a predictor of cardiovascular events in patients with heart failure. Improvement of LA function and reverse remodeling was observed after cardiac resynchronization therapy (CRT). OBJECTIVE: The purpose of this study was to explore the clinical significance of improvement in LA function after CRT. METHODS: ...
Saremi Farhood - - 2008
BACKGROUND: Previous reports have shown that computed tomography (CT) is a useful, noninvasive test for detecting atrial thrombi. However, blood stasis in the left atrial appendage (LAA) of patients with atrial fibrillation (AF) may be a common cause for false-positive results. OBJECTIVES: We retrospectively evaluated the prevalence of filling defects ...
Boyle Noel G - - 2008
Atrial fibrillation (AF) and congestive heart failure (CHF) are common cardiac conditions that frequently coexist. There is a complex interplay between the two conditions, with each increasing the morbidity and mortality associated with the other. The management of AF in patients with CHF requires special care because of the increased ...
Ucar Halil I - - 2008
OBJECTIVE: To evaluate the roles of surface electrocardiogram (ECG) and transthoracic echocardiography (ECHO) for prediction of atrial fibrillation (AF) after coronary artery bypass grafting (CABG). METHODS: This study was conducted from 2002-2004 at the Cardiovascular Department of Hacettepe University, Ankara, Turkey. Seventy consecutive patients were enrolled in this study that ...
Geha Alexander S - - 2008
Atrial fibrillation (AF) affects several million patients worldwide and is associated with a number of heart conditions, particularly coronary artery disease, rheumatic heart disease, hypertension, and congestive heart failure. The treatment of AF and its complications is quite costly. Atrial fibrillation usually results from multiple macro-re-entrant circuits in the left ...
Schmieder Roland E - - 2008
BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia and increases cardiovascular risk in hypertensive patients. Therefore, in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) a prespecified objective was to compare the effects of valsartan and amlodipine on new-onset AF. METHODS: A total of 15 245 hypertensive patients at high ...
Dougu N - - 2008
We created an algorithm for diagnosing subtypes of cerebral infarction (CI) during the acute stage by combining atrial fibrillation (AF) and D-dimer levels. One-hundred and eight patients hospitalized for acute CI were retrospectively analyzed. CI was classified into cardioembolic, atherothrombotic, lacunar infarction or others. Patients were classified in AF group ...
Richter Ulrike - - 2008
BACKGROUND: The present study investigates spatial properties of atrial fibrillation (AF) by analyzing vectorcardiogram loops synthesized from 12-lead electrocardiograms (ECGs). METHODS: After atrial signal extraction, spatial properties are characterized through analysis of successive, fixed-length signal segments and expressed in loop orientation, that is, azimuth and elevation, as well as in ...
Avitall Boaz - - 2008
BACKGROUND: Atrial fibrillation (AF) with poorly controlled ventricular response is known to be detrimental to ventricular function, conversely, heart failure (HF) increases susceptibility to AF. OBJECTIVE: This study sought to examine the electropathological effects of 3 months of atrial fibrillation (AF) in dogs with and without concomitant ventricular dysfunction. METHODS: ...
Burstein Brett - - 2008
Atrial fibrillation (AF) is the most common arrhythmia in the clinical setting, and traditional pharmacological approaches have proved to have important weaknesses. Structural remodeling has been observed in both clinical and experimental AF paradigms, and is an important feature of the AF substrate, producing fibrosis that alters atrial tissue composition ...
Ehrlich Joachim R - - 2008
Atrial-selective pharmacologic approaches represent promising novel therapeutic options for the treatment of atrial fibrillation (AF). Medical treatment for AF is still more widely applied than interventional therapies but is hampered by several important weaknesses. Besides limited clinical efficacy (cardioversion success and sinus-rhythm maintenance), side effects like ventricular proarrhythmia and negative ...
Boldt Leif-Hendrik - - 2008
Effectiveness, safety, and other factors associated with success of cardioversion (CV) of atrial fibrillation (AF) have not yet been evaluated in patients with reduced left ventricular ejection fraction. We studied 148 consecutive patients with left ventricular dysfunction (ejection fraction < or = 45%), who underwent electrical CV for AF in ...
Cruz-Gonzalez Ignacio - - 2009
Patients with atrial fibrillation are at an increased risk of having a cardioembolic stroke. Most of the thrombi responsible for these ischemic events originate in the left atrial appendage (LAA). Several surgical and percutaneous endovascular techniques have been explored to occlude the LAA. As an alternative of the surgical closure, ...
Tan Eng S - - 2008
AIMS: To investigate long-term outcome and to determine predictors of development of heart failure (HF) in patients with atrioventricular (AV) node ablation and permanent right ventricular pacing because of symptomatic refractory atrial fibrillation (AF). BACKGROUND: Atrioventricular node ablation and subsequent permanent pacing is a well-established therapy for patients with AF. ...
Nagarakanti Rangadham - - 2008
INTRODUCTION: Isolated diastolic heart failure (DHF) is defined as heart failure with preserved left ventricular (LV) systolic function in the absence of valve disease. DHF is a clinical diagnosis confirmed by echocardiography and is presumed to be due to diastolic dysfunction (DD). DD is characterized by abnormalities in relaxation and/or ...
Lin Yenn-Jiang - - 2008
BACKGROUND: Temporal variation in complex fractionated atrial electrograms (CFAEs) exists during atrial fibrillation (AF). OBJECTIVE: This study sought to quantify the variation in CFAEs using a fractionation interval (FI) algorithm and to define the shortest optimal recording duration required to consistently characterize the magnitude of the fractionation. METHODS: Twenty-seven patients ...
Mayr Manuel M Cardiovascular Division, King's College, London, United Kingdom. - - 2008
We sought to decipher metabolic processes servicing the increased energy demand during persistent atrial fibrillation (AF) and to ascertain whether metabolic derangements might instigate this arrhythmia. Whereas electrical, structural, and contractile remodeling processes are well-recognized contributors to the self-perpetuating nature of AF, the impact of cardiac metabolism upon the persistence/initiation ...
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