Saturday, October 31, 2009

Role of Inflammation in Early AF Recurrence after PV Isolation

Citation : Rupa Bala.Role Of Inflammation In Early AF Recurrence After PV Isolation .JAFIB.2009 October;Volume 1 Issue(9): 555-558.

Recently, there has been a great deal of interest in the mechanistic role of inflammation in the initiation, maintenance, and perpetuation of atrial fibrillation (AF). Several studies have focused on inflammatory biomarkers and acute-phase proteins to further understand the inflammatory milieu in relation to AF. These studies have demonstrated that both interleukin-6 (IL-6) and C-reactive protein (CRP) are elevated in paroxysmal and persistent AF. Chung et al. demonstrated an association between elevated CRP levels and AF in a nonoperative setting. In this study, CRP levels were more than 2-fold higher in patients with AF than in control subjects. Moreover, patients with persistent AF had higher CRP levels than patients with paroxysmal AF, suggesting that inflammation may be more relevant to promoting AF maintenance than its initiation.

The Role of Intracardiac Echocardiography in Atrial Fibrillation Ablation

Citation : Elad Anter, Mathew D. Hutchinson, David J. Callans.The Role of Intracardiac Echocardiography in Atrial Fibrillation Ablation .JAFIB.2009 October;Volume 1 Issue(9): 545-554.

Radiofrequency catheter ablation of pulmonary veins has emerged as an effective therapy for patients with symptomatic atrial fibrillation. Advances in real-time intracardiac echocardiography with 2D and Doppler color flow imaging have led to its integration in atrial fibrillation ablation procedures. It allows imaging of the left atrium and pulmonary veins, including identification of anatomic variations. It has an important role in guiding transseptal catheterization, imaging the pulmonary vein ostia, assisting in accurate placement of mapping and ablation catheters, monitoring lesion morphology and flow changes in the ablated pulmonary veins, hence allowing titration of energy delivery. Importantly, it allows instant detection of procedural complications.

Atrial Fibrillation in Hypertrophic Obstructive Cardiomyopathy - Antiarrhythmics, ablation and more!

Citation : Gangadhar Malasana, John D. Day, T. Jared Bunch.Atrial Fibrillation in Hypertrophic Obstructive Cardiomyopathy - Antiarrhythmics, ablation and more! .JAFIB.2009 October;Volume 1 Issue(9): 535-544.

Hypertrophic cardiomyopathy (HCM) is a genetic disease of the cardiac sarcomere with an autosomal dominant pattern of inheritance. Patients with HCM are at high risk of developing atrial fibrillation (AF) particularly in the setting of advanced diastolic dysfunction and left atrial enlargement. AF is a marker of increased mortality and morbidity and results in a significant reduction in quality of life. Antiarrhythmic medications improve symptoms and reduce AF recurrence, but few are safe and there exists little data to guide their long-term use in HCM. Non-pharmacologic approaches have emerged and have equal or greater efficacy than pharmacologic approaches. Although these approaches are promising, the long-term impact on atrial function needs to be carefully studied as it may impact quality of life in patients that age in the setting of a progressive diastolic disease disorder. Nonetheless, with the significant impact of AF in HCM, rhythm control strategies are often required. The understanding of rhythm control strategies in HCM, an often rapidly progressive diastolic dysfunction disorder, may provide insight in how to treat the much more prevalent AF patient with hypertensive cardiomyopathy. Regardless of treatment strategy (rhythm or rate control) patients are a moderate to high risk of thromboembolism and until data are available to suggest otherwise require long-term warfarin anticoagulation.

Review of Dominant Frequency Analysis in Atrial Fibrillation

Citation : Rakesh Latchamsetty, Abraham G Kocheril.Review of Dominant Frequency Analysis in Atrial Fibrillation .JAFIB.2009 October;Volume 1 Issue(9): 531-534.

Significant advancements have been made in the technology and approach to catheter ablation of atrial fibrillation (AF). Pulmonary vein isolation has emerged as the predominate strategy in this procedure and has fueled innovations in catheter design as well as various mapping and navigation systems. Mapping and targeting of complex fractionated atrial electrograms has also emerged as an additional or alternate strategy employed by some ablationists. Recently, attention is being drawn to a new approach targeting atrial sites with high dominant frequencies (DF) derived from their electrograms. This article is a review of the basic concepts of DF, some of the literature on which these were based, and the potential clinical applicability of DF analysis for ablation of AF.

Pulmonary Vein Isolation using a High Density Mesh Ablator Catheter: incorporation of three-dimensional navigation and mapping

Citation :Dr Jiun Tuan, Dr Mohamed Jeilan, Dr Faizel Osman, Dr Suman Kundu, Dr Rajkumar Mantravadi, Dr Peter J Stafford, Dr G Andre Ng.Pulmonary Vein Isolation using a High Density Mesh Ablator Catheter: incorporation of three-dimensional navigation and mapping .JAFIB.2009 October;Volume 1 Issue(9): 510-518.

Background We evaluated the use of a novel High Density Mesh Ablator (HDMA) catheter in combination with three-dimensional navigation for the treatment of paroxysmal atrial fibrillation.
Methods The HDMA catheter was used to carry out pulmonary vein isolation in a consecutive series of patients. Three-dimensional geometry of the left atrial-pulmonary vein (LA-PV) junctions were first created with the HDMA catheter. Ostial, proximal and distal sites within the pulmonary veins were tagged with catheter shadows on the created geometry to allow for re-interrogation of these exact sites after ablation.
Results The HDMA catheter was successfully used to create three dimensional geometry of the LA-PV junction in a total of 20 pulmonary veins which involved 5 patients. In all cases, ostial ablation alone was sufficient to achieve electrical isolation. No significant pulmonary vein stenosis was seen acutely after ablation.
Conclusion We describe the successful use of the novel HDMA catheter to create three-dimensional geometry of the LA-PV junction to assist with pulmonary vein isolation.

Percutaneous Left Atrial Appendage Occlusion Therapy: Who, Why and How?

Citation : Sven Mobius-Winkler, Ingo Dahnert, Gerhard C. Schuler and Peter B. Sick.Percutaneous Left Atrial Appendage Exclusion Therapy: Who, Why and How? .JAFIB.2009 October;Volume 1 Issue(9): 519-530.

The diagnosis of atrial fibrillation (AF) significantly increases the risk of having cardio embolic events. Cerebrovascular events are still a leading cause of death and disability worldwide. Current guidelines recommend an antithrombotic regimen to prevent thromboembolism in medium and high risk patients with AF. However, a substantial number of patients are not eligible for this therapy. Therefore, an exclusion of the left atrial appendage (LAA) from circulation seems to be an alternative strategy for stroke prevention in AF. This review focuses on the different strategies for LAA exclusion with a special focus on the WATCHMAN®-device.

Two devices are currently in use for percutaneous transcatheter occlusion of the LAA: the WATCHMAN®-device and the AMPLATZER®–Cardiac plug. Only for the WATCHMAN®-device safety, feasibility and non inferiority data compared to standard therapy data are currently available.

Additionally, about 200 patients at high risk for thromboembolic stroke and contraindications for oral anticoagulation therapy received the PLAATO® –device which is currently off the market.

The WATCHMAN®-device was implanted in 800 patients that were eligible for long-term anticoagulation therapy with a moderate risk for thromboembolic stroke due to non-valvular AF.

Current evidence indicates an equivalent risk of stroke compared to oral anticoagulation with a reduced rate of bleeding complications at least for the WATCHMAN®-device. Hence, another therapeutic option now is available to prevent thrombembolic events in patients with atrial fibrillation not suitable for medical anticoagulation therapy.

Key Words : atrial fibrillation, stroke, left atrial appendage, WATCHMAN® - device, Amplatzer® septal occluder, Amplatzer® cardiac plug