Impact of High-Power Short-Duration Radiofrequency Ablation on Long-Term Lesion Durability for Atrial Fibrillation Ablation.

Objectives: The goal of this study was to compare lesion durability between high-power short-duration (HP-SD) and moderate-power moderate-duration (MP-MD) ablation strategies.

Background: HP-SD radiofrequency ablation (RFA) was developed to improve pulmonary vein isolation (PVI) by reducing the effect of catheter instability inherent to MP-MD ablation strategies. However, its long-term effect on lesion durability for the treatment of atrial fibrillation is unknown.

Evaluation of a novel high-resolution mapping technology for ablation of recurrent scar-related atrial tachycardias.

Background: Rhythmia is a new technology capable of rapid and high-resolution mapping. However, its potential advantage over existing technologies in mapping complex scar-related atrial tachycardias (ATs) has not yet been evaluated.

Objective: The purpose of this study was to examine the utility of Rhythmia for mapping scar-related ATs in patients who had failed previous ablation procedure(s).

Comparison of intracardiac echocardiography and transesophageal echocardiography for imaging of the right and left atrial appendages.

Background: Transesophageal echocardiography (TEE) is the standard for diagnosis of atrial thrombi and is performed before ablation of atrial arrhythmias. Intracardiac echocardiography (ICE) is routinely used during these procedures and may provide an alternative imaging modality.

Objective: The purpose of this study was to compare TEE and ICE for right atrial appendage (RAA) and left atrial appendage (LAA) anatomy and thrombus.

Treatment of obstructive sleep apnea reduces the risk of atrial fibrillation recurrence after catheter ablation.

Objectives: The aim of this study was to examine the effect of continuous positive airway pressure (CPAP) therapy on atrial fibrillation (AF) recurrence in patients with obstructive sleep apnea (OSA) undergoing pulmonary vein isolation (PVI).

Background: OSA is a predictor of AF recurrence following PVI. However, the impact of CPAP therapy on PVI outcome in patients with OSA is poorly known.

Acute performance of a right ventricular automatic pacing threshold algorithm for implantable defibrillators.

Introduction: Automatic pacing threshold (AT) testing with threshold trending and output adjustment may simplify follow-up and improve cardiac rhythm device longevity. The objective of this study was to evaluate the performance of a new right ventricular (RV) AT algorithm for implantable cardioverter defibrillators (ICDs) using RVcoil to Can evoked response sensing.

Method: Patients undergoing ICD, with or without cardiac resynchronization therapy device, implant, replacement, or upgrade were enrolled.

Segmentation and registration of three-dimensional rotational angiogram on live fluoroscopy to guide atrial fibrillation ablation: a new online imaging tool.

Background: Three-dimensional rotational atriography (3DATG) was developed to supplement two-dimensional fluoroscopy with 3D volume reconstruction of the left atrium (LA), pulmonary veins (PV), and other structures. Until recently, 3DATG images could only be viewed separately and were not suitable to directly guide atrial fibrillation (AF) ablation.

Objective: The purpose of this study was to evaluate the feasibility and accuracy of intraprocedural 3DATG.

Baseline myocardial perfusion predicts response to cardiac resynchronization therapy: a prospective observational study.

Purpose: We prospectively determined whether preimplant myocardial perfusion imaging (MPI) predicts outcome with biventricular pacing (BiVP).

Methods: Single-photon emission computed tomography (SPECT) MPI, left ventricular (LV) volumes, ejection fraction (EF), 6-min hall walk (6MW) were assessed at baseline and at 4 months in 19 patients with ischemic cardiomyopathy undergoing BiVP. Clinical and hemodynamic responses were correlated with MPI.

Computed tomography-fluoroscopy overlay evaluation during catheter ablation of left atrial arrhythmia.

Aims: Proper visualization of left atrial (LA) and pulmonary vein (PV) anatomy is of crucial importance during atrial fibrillation (AF) ablation. This two-centre study evaluated a new automatic computed tomography (CT)-fluoroscopy overlay system (EP navigator, Philips Medical Systems, Best, The Netherlands) and the accuracy of different registration methods.

Methods And Results: Fifty-six consecutive patients (age: 56 +/- 14) with symptomatic AF underwent contrast CT of the LA/PV prior to ablation.

Remote magnetic navigation system provides a superior catheter stability in acquisition of His bundle electrogram.

Introduction: Catheter stability is a key prerequisite for a successful EP procedure. Remote magnetic navigation system (RMNS) was recently introduced for the manipulation of EP catheters. It may provide an improved catheter stability but this has not been tested prospectively.

Evaluation of left atrial and posterior mediastinal anatomy by multidetector helical computed tomography imaging: relevance to ablation.

Introduction: Increasing use of catheter ablation in the left atrium (LA) requires understanding of substrate anatomy, especially with regard to potential damage to adjacent structures.

Methods And Results: We reviewed multidetector helical computed tomography (MDCT) imaging on 42 subjects, 26 imaged before planned LA ablation for atrial fibrillation (AF), and 16 without AF. LA volume and dimensions were larger in patients with AF (p < 0.

Three-dimensional rotational angiography of the left atrium and esophagus--A virtual computed tomography scan in the electrophysiology lab?

Background: Three-dimensional (3D) reconstruction of the heart and surrounding structures has been supplementing traditional two-dimensional imaging to guide diagnostic and therapeutic electrophysiologic procedures. Current methods using computed tomography (CT)/magnetic resonance imaging (MRI) reconstruction have certain limitations.

Objective: We investigated the feasibility of rotational angiography (RA) combined with simultaneous esophagogram to create an intraprocedural 3D reconstruction of the left atrium (LA) and the esophagus.

Sheathless implantation of permanent coronary sinus-LV pacing leads.

Background: Implantation of CS-LV pacing leads is usually accomplished through specialized sheaths with additional use of contrast venography and other steps. Direct implantation at a target pacing site could provide a simplified procedure with appropriate leads.

Methods: A progressive CS-LV lead implant protocol was used, with initial attempts made to place the lead directly using only fluoroscopy and lead stylet or wire manipulation.

Lack of a hypotensive effect with rapid administration of a new aqueous formulation of intravenous amiodarone.

Hypotension is the most frequent adverse event reported with intravenous amiodarone. Hypotension has been attributed to the vasoactive solvents of the standard formulation (Cordarone IV) and is not dose related, but related to the rate of infusion. Drug labeling calls for intravenous amiodarone to be administered over 10 minutes.

Intravenous lidocaine versus intravenous amiodarone (in a new aqueous formulation) for incessant ventricular tachycardia.

The effectiveness of intravenous amiodarone for the treatment of incessant (shock resistant) ventricular tachycardia (VT) has not been established. This study evaluated the efficacy of a water-soluble amiodarone preparation or lidocaine for the treatment of shock-resistant VT. The trial was a double-blinded parallel design.

Algorithms useful in the treatment of atrial fibrillation.

Atrial fibrillation (AF) is a heterogeneous disorder; its management must be individualized depending upon the mode of presentation, underlying substrate, and need for either rate or rhythm control. In hemodynamically unstable patients with new onset AF, conversion by electrical cardioversion is the preferred approach; however, in stable patients pharmacological options may be considered. Recurrence rate after conversion is high in the majority of patients, necessitating the use of antiarrhythmic agents.