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Mapping strategies that enhance understanding and therapy for atrial fibrillation (AF) remain essential. The paced electrogram feature analysis (PEFA) technique has previously identified slow conduction zones within the ventricle critical for ventricular fibrillation (VF) or ventricular tachycardia. This prospective, exploratory cohort study aimed to determine if PEFA identifies similar slow conduction zones in the left atrium (LA) of patients with AF compared to controls.The study compared patients with paroxysmal AF undergoing catheter ablation with a control group of non-AF patients undergoing left-side electrophysiological procedures. Four electrogram (EGM) characteristics were assessed in the LA at various locations: EGM duration (ms), last deflection (ms), voltage (mV), and latency (ms). Normal values were established from the control cohort and used to calculate the percentage of abnormal EGM features in AF patients. The study included 24 AF patients and 8 controls. AF patients exhibited a higher proportion of abnormal EGM values compared to controls: last deflection 17.2%, latency 16.4%, voltage 8.5%, and EGM duration 9.8%. Normal values determined from the analysis were: 201.5 ms for last deflection, 84.3 ms for EGM duration, 77.7 ms for latency, and 0.26 mV for voltage. This study employed PEFA in the LA to identify previously undescribed metrics of atrial myopathy associated with AF. PEFA represents a potential method for characterizing the AF substrate by targeting abnormal atrial responses to closely coupled stimulation. [ABSTRACT FROM AUTHOR]

Objective It remains unclear whether atrial fibrillation (AF) alone determines systemic changes in hemocoagulation. Our aim was to examine the prothrombin fragment F1+2 and fibrinopeptide A (FPA) as early markers of coagulation activity still in the first twenty-four hours of paroxysmal AF (PAF) and to correlate them with the arrhythmia onset. Methods 51 non-anticoagulated patients (26 men, 25 women, aged 59.84±1.6 years) and 52 controls (26 men, 26 women, aged 59.50±1.46 years) were sequentially selected. F1+2 and FPA plasma levels were measured by enzyme-linked immunoassays. Results F1+2 was significantly higher in patients (292.61pmol/L±14.03pmol/L vs 183.40pmol/L±8.38pmol/L; p<0.001). FPA was also substantially higher (4.47ng/mL±0.25 ng/mL vs 3.09ng/mL±0.15ng/mL, p<0.001). Among the potential predictors for these deviations: age, gender, BMI, PAF duration and CHA2DS2-VASc score, it was established that higher F1+2 and FPA plasma levels were independently associated only with PAF duration (p<0.05). Moreover, longer episodes were associated with higher values of F1+2 (Adjusted R² = 0.68) and FPA (Adjusted R² = 0.70). Conclusion Increased coagulation activity was present still in the first twenty-four hours of PAF clinical presentation. The disease itself was associated with increasing hypercoagulability over time, suggesting its importance as an independent risk factor for thromboembolic events. [ABSTRACT FROM AUTHOR]

Coronary artery spasm during catheter ablation for arrhythmias is a rare but previously reported complication. Timing of presentation, manifestations of vasospasm, and purported mechanisms vary somewhat in the prior literature. We present a case of chest pain, inferior lead ST elevation, and complete AV block with angiographically confirmed right coronary artery (RCA) vasospasm that occurred immediately after catheter ablation for atrial fibrillation. [ABSTRACT FROM AUTHOR]

There is extensive knowledge in the ablation of ventricular arrhythmias in patients with Chagas' cardiomyopathy, as well as specific characteristics of the arrhythmogenic substrate, and the need for an epicardial approach to achieve success. On the contrary, no publications currently address the ablation of atrial fibrillation in these patients or the characteristics of the arrhythmia such as the successful ablation sites. Our two case reports highlight the association of Chagas' disease with atrial arrhythmias, the tailored approach that was needed to give an appropriate treatment and a discussion of our current knowledge of Chagas' cardiomyopathy as a substrate for atrial arrhythmias. [ABSTRACT FROM AUTHOR]

The identification of individuals at high risk of developing atrial fibrillation (AF) is important to prevent potentially lethal and invalidating complications of this arrhythmia. Recently, several studies have investigated the association between PR-interval and the risk of AF and have tested the value of PR-interval in personalized risk scores for AF. However, the results of these studies are generally conflicting. When looking for an association between a prolonged PR-interval (first-degree atrioventricular [AV] block vs. normal PR-interval) and an increased risk of AF, not all studies were able to find a consistent and statistically significant association. In two recent studies, however, the investigators were able to show an increased risk of AF for individuals with PR-intervals in the short range compared with individuals in the middle range. The existence of a true U-shaped relationship could potentially explain part of the conflicting results from investigators only looking for an increased risk for longer PR-intervals. However, regardless of these speculations, the association seems relatively weak. The significance of PR-interval in risk prediction of AF has been tested in three independent risk scores where model selection primarily was based on improvement in c-statistics. In one risk score, PR-interval improved the predictive value of the risk model, whereas it did not in the other two risk scores. Further studies are warranted before any final conclusion can be drawn, although based on the current evidence, it is reasonable to conclude that the predictive value of PR-interval in AF risk prediction is limited. [ABSTRACT FROM AUTHOR]

The article presents a study that investigates ways on how to control the rates of atrial fibrillation (AF) and prevent morbidity in patients in the U.S. It offers information on the role of increase heart rates in the morbidity of patients with AF. It presents the efficacy of using anti-arrhythmics and sinus rhythm in controlling AF. It features the medical tools used by doctor to control patients' morbidity and the benefits of controlling the AF morbidity rates. Moreover, the different clinical trials done by researchers andt its results are also mentioned.

Respiration influences the sinus heart rate, however, little is still known about the tachyarrhythmias related to respiration. Atrial tachycardia (AT) rarely emerges during inspiration and it also ceases during expiration. This type of AT is thus called respiratory cycle-dependent atrial tachycardia (RCAT), and it demonstrates a centrifugal activation pattern. Based on these peculiar P wave morphologies, the foci converged either around the right superior pulmonary vein (RSPV) or inside the superior vena cava where the anterior right ganglionated plexi (ARGP) is considered to be located. The mechanism of such AT is therefore thought to be related to the activity of the autonomic system. [ABSTRACT FROM AUTHOR]

Underlying mechanisms of atrial fibrillation occurrence and its self-extinguishing remain not completely investigated yet. The role of autonomic tone and sinoatrial node in the interplay between atrial fibrillation and sinus rhythm is also not fully understood. The influence of inflammation as a possible source of arrhythmia and likelihood of its pharmacologic treatment deserves special attention. These complex issues are important for better understanding of arrhythmogenesis and rhythm control. Conceptual reconsiderations through the new insights primarily on the hypothetic basis may delineate new therapeutic and preventive strategies. The aim of this analytical review was to reinforce the clinical and laboratory studies regarding the role of: 1) autonomic tone and sinoatrial node in restitution of sinus rhythm, 2) new concept of "vibrantly quiescent stroboscopic tuning" as a matured status of atrial fibrillation being prepared for its abruption by slight impulse, 3) inflammation in the interplay between atrial fibrillation and sinus rhythm, 4) anti-inflammation and anti-allergic therapy to prevent and to treat the arrhythmia. [ABSTRACT FROM AUTHOR]

Quality of life (QoL) is a very important endpoint in trials reporting the efficacy of catheter ablation in patients with atrial fibrillation (AF). It has been shown that AF ablation significantly improves the QoL, but recent studies question the usefulness of the most used generic QoL instrument in AF patients. The complexity of the disease makes it mandatory to employ disease specific instruments in the assessment of QoL. This paper reviews the current knowledge of various QoL instruments, including the limitations and pitfalls, and the impact of AF ablation on the QoL [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most frequent supraventricular arrhythmia with an approximative prevalence of 1 % in the general population and above 6 % in the elderly. After a first AF diagnosis, the hospitalization rate is markedly increased. Management of a first AF episode is different depending on the clinical status of patients. Practical guidelines developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society are available for the management of these patients. A four-step decisional scheme must be followed in the management of a first recent AF episode: need for a short- and long-term anticoagulation, define a rythmologic strategy (rhythm or rate control), select the weapon (drug, device or ablation) and reconsider the strategy if needed. After a first uncomplicated paroxysmal AF episode, guidelines recommend that prescription of antiarrhythmics must be avoided and anticoagulation is optional. After a first persistent AF episode, guidelines recommend to either respect or reduce the arrhythmia. Prescription of antiarrhythmics and anticoagulation is also optional depending on the patient's condition. In case of the AF reduction decision, anticoagulation must be tailored preliminary to this reduction. AF recurrence rate varies depending on the patient's condition, and the risk of stroke assessed by the CHA2DS2-VASc score might be similarly considered for both paroxysmal and persistent AF. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most common arrhythmia and is a significant burden to healthcare cost. AF causes congestive heart failure, thromboembolic events such as stroke and intolerable symptoms in some patients. With the advances and increasing experience in catheter ablation, there is now an established role for catheter ablation in patients with atrial fibrillation. The risks, complications and patient features associated with it are increasingly recognized. A recent worldwide survey has shown an increasing number of medical centers that are practicing catheter ablation of atrial fibrillation, predominantly with pulmonary vein isolation techniques. However, catheter ablation is an invasive therapy in AF and is associated with a few major complications. Patient selection, ablation technique, and catheter energy source all influence the efficacy and safety of the procedure. Finally, while several randomized control trials have compared the efficacy of catheter ablation versus antiarrhythmic drug therapy, a number of trials are on the horizon to explore its role as a first line therapy for atrial fibrillation. New energy catheter energy sources are also being explored. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmia and is associated with increased morbidity and mortality due to stroke and thrombo-embolism. In patients with AF, strokes are usually more severe, resulting in longer hospital stays, worse disability and considerable healthcare costs. The prevention of stroke therefore is crucial in the management of AF. Stroke risk stratification tools can be used to determine patients at higher risk of stroke, and if no contraindications are present oral anticoagulation (OAC) therapy can be initiated. Despite the strong evidence for the benefit of OAC in stroke prevention in patients with AF, the use of thromboprophylaxis remains inadequate. The key measures to prevent stroke in patients with AF include: adequate stroke risk assessment and thrombo-prophylaxis; prompt initiation of OAC and avoidance of interruptions; earlier detection of AF; and education to overcome the under-usage of OAC in elderly patients. [ABSTRACT FROM AUTHOR]

The article focuses on the role of temporal and spatial indices of atrial fibrillation (AF) regularization in detecting intra-procedural termination and result. It outlines several studies that examines the predictors of acute procedural termination of AF using Bordeaux stepwise approach, receiver operating characteristic analyses, and intra-cardiac method in patients with AF. It outlines the results of the mentioned studies, which show that several quantitative indices may detect the acute procedural termination of AF, however, most have suboptimal predictive value that do not identify the stage in which AF will regularize or terminate.

The article presents a study that examines the susceptibility of patients with atrial fibrillation (AF) to arrhythmia recurrence and congestive heart failure after a successful ablation. It outlines the method of the study that investigates 194 patients with lone AF who underwent pulmonary vein antrum isolation (PVAI) guided by a circular mapping catheter. It presents the data of the long-term follow-up of the trial, as well as the result, which indicates that lone AF patients should be defined as atrial fibrillation in patients under 75 years of age, however, patients with history of heart surgery or any comorbidities should be excluded.

The article discusses the effect of various ablation interventions on the result in patients with longstanding persistent atrial fibrillation (AF). It cites ablation techniques including pulmonary vein isolation (PVI), linear ablation in addition to PVI, and the stepwise ablation approach. It states that the use of single interventions during each procedure is often unsuccessful. A chart depicting the calculated values for the single ablation procedure and multiple ablation techniques is presented. Furthermore, developing new quantitative methods for substrate characterization is helpful in improving the mechanistic understanding of the relationship between anatomic and electrophysiologic remodeling in the left atrium, and the development of longstanding persistent atrial fibrillation.

The article discusses the evidence on the association between atrial fibrillation (AF) and endurance sport practice, as well as the clinical characteristics of arrhythmia, the pathophysiological mechanisms responsible for this association, and the available therapeutic options. It mentions the risk factors for developing AF which include diabetes mellitus and hyperthyroidism. A chart depicting the increased risk in AF in individuals practising endurance sports is presented. It focuses on the possibility that autonomic nerves and exercise-related structural changes in the atria contribute to the pathophysiologic mechanisms for increased AF risk in individuals. It notes that limiting physical activity reduces the risks for AF in athletes.

The left atrial appendage (LAA) has recently been recognized as a potential source of arrhythmia in patients undergoing repeat ablation procedures for atrial fibrillation (AF). In this case report we describe sustained fibrillation contained entirely within the LAA, that continued even after electrical isolation of the LAA was performed. This case supports the concept that in selected patients with AF, catheter ablation strategies may need to incorporate LAA isolation to minimize recurrence [ABSTRACT FROM AUTHOR]

Left atrial appendage aneurysm (LAAA) is a rare entity. Clinical manifestations include arrhythmias and systemic embolization. We show here an example of a large and ectopic LAAA mimicking a mediastinal mass on chest X-ray and presenting with incessant atrial arrhythmias. Subsequent investigations leading to the correct diagnosis are described. [ABSTRACT FROM AUTHOR]