Mechanisms of action behind the protective effects of proactive esophageal cooling during radiofrequency catheter ablation in the left atrium.

Proactive esophageal cooling for the purpose of reducing the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation procedures is increasingly being used and has been Food and Drug Administration cleared as a protective strategy during left atrial RF ablation for the treatment of atrial fibrillation. In this review, we examine the evidence supporting the use of proactive esophageal cooling and the potential mechanisms of action that reduce the likelihood of atrioesophageal fistula (AEF) formation. Although the pathophysiology behind AEF formation after thermal injury from RF ablation is not well studied, a robust literature on fistula formation in other conditions (eg, Crohn disease, cancer, and trauma) exists and the relationship to AEF formation is investigated in this review.

Uncovering the Invisible: The Role of High-density Catheters in Recognizing Fractionated Signals in Pulmonary Vein Isolation.

The HD Grid multipolar mapping catheter has emerged as an invaluable tool for greater effectiveness of pulmonary vein isolation (PVI). In the cases described here, fractionated signals seen with the HD Grid catheter at the left atrial appendage (LAA) and left superior pulmonary vein (LSPV) junction were ablated. These signals are not likely to be visualized with conventional catheters and may cause recurrences due to incomplete PVI.

An Uncommon Focus of a Common Phenomenon: Superior Vena Cava Triggering Atrial Fibrillation.

Ablation of atrial fibrillation most commonly involves the pulmonary veins; however, the superior vena cava (SVC) is an important potentially arrhythmogenic structure that should not be overlooked. This case report demonstrates an excellent example of triggering activity localized to the SVC and the subsequent conversion to sinus rhythm with ablation of the SVC.

Atrioesophageal Fistula Rates Before and After Adoption of Active Esophageal Cooling During Atrial Fibrillation Ablation.

Background: Active esophageal cooling reduces the incidence of endoscopically identified severe esophageal lesions during radiofrequency (RF) catheter ablation of the left atrium for the treatment of atrial fibrillation. A formal analysis of the atrioesophageal fistula (AEF) rate with active esophageal cooling has not previously been performed.

Objectives: The authors aimed to compare AEF rates before and after the adoption of active esophageal cooling.

An interesting case of infra-hisian block.

Introduction: The management of patients with conduction disease and supraventricular arrhythmias presents a multitude of clinical challenges.Intra-Hisian block, a condition characterized by delayed or blocked electrical conduction within the His bundle, can result in debilitating symptoms, such as syncope or presyncope. This case report aims to elucidate the diagnostic and therapeutic considerations that were taken in a patient who presented with recurrent syncopal episodes that corresponded to atrial flutter (AFL) and subsequently underwent cavotricuspid isthmus ablation.

Epicardial Potential in the Left Atrium During Posterior Wall Isolation in Persistent Atrial Fibrillation.

Pulmonary vein isolation (PVI) is used for rhythm control in atrial fibrillation (AF). Posterior wall isolation (PWI) is often an adjunct to PVI. Successful PWI is limited by esophageal location, epicardial bridging signals, tissue thickness, and mapping catheter resolution.

Improved left atrial appendage closure procedural efficiency using radiofrequency transseptal wire system.

Objective: The radiofrequency (RF) needle has been shown to improve transseptal puncture efficiency and safety compared to mechanical needles. This study aimed to investigate the use of VersaCross RF transseptal wire system (Baylis Medical) to improve procedural efficiency of left atrial appendage closure (LAAC) compared to the standard RF needle-based workflow.

Methods: Eighty-one LAAC procedures using WATCHMAN FLX were retrospectively analyzed comparing the standard RF needle-based workflow to a RF wire-based workflow.

Implantable Cardioverter-defibrillator Magnetic Interference by the iPhone 12: Is It Clinically Significant?

The iPhone 12 series (Apple, Inc., Cupertino, CA, USA) contains a circular array of magnets around a central charging coil (compatible with "Magsafe" technology). The device was recently reported to have magnetic interference with implantable cardioverter-defibrillators (ICDs).

Choice of Steerable Sheath Impacts Contact Force Stability During Pulmonary Vein Isolation.

A stable contact force (CF) is correlated with more effective radiofrequency (RF) ablation (RFA) lesions and long-term procedural outcomes. Efforts to improve catheter stability include jet ventilation, pacing, steerable sheaths, and CF-sensing ablation catheters. This study compares CF stability and effective RF lesions between two commercially available steerable sheaths.

Long-term use of the wearable cardioverter defibrillator in patients with explanted ICD.

Objectives: To evaluate the effectiveness of wearable cardioverter defibrillator (WCD) use in protecting patients from sudden cardiac arrest (SCA) while they were treated in nonhospital settings until re-implantation of an Implantable cardioverter-defibrillator (ICD) was feasible. We sought to determine whether the WCD could be successfully utilized long term (≥1 year) after ICD extraction in patients at continued risk of SCD in which ICD re-implantation was not practical.

Background: ICDs have proven to improve mortality in patients for both secondary and primary prevention of SCA.

Successful fluoroless radiofrequency catheter ablation of supraventricular tachycardia during pregnancy.

Even in the absence of underlying heart disease, pregnancy is known to increase susceptibility supraventricular tachycardia (SVT). This brings a management challenge, mainly due to concerns about pharmacotherapy and radiation to the fetus. This case highlights the capability of using fluoroless mapping technologies to treat refractory arrhythmia cases safely and successful.

Concomitant Wolff-Parkinson-White and Atrioventricular Nodal Reentrant Tachycardia: Which Pathway to Ablate?

Background: Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common form of supraventricular tachycardia. In contrast, Wolff-Parkinson-White (WPW) pattern consists of an accessory pathway, which may result in the development of ventricular arrhythmias. Frequent tachycardia caused by AVNRT and accessory pathways may play a role in left ventricular systolic dysfunction.

Outcome of percutaneous continuous drainage of psoas abscess: A clinically guided technique.

Background: Percutaneous aspiration of abscesses under ultrasonography (USG) and computer tomography (CT) scan has been well described. With recurrence rate reported as high as 66%. The open drainage and percutaneous continuous drainage (PCD) has reduced the recurrence rate.

Medtronic Sprint Fidelis lead recall: determining the initial 5-year management cost to Medicare.

Background: The Medtronic Sprint Fidelis defibrillator lead has a high failure rate and was recalled in October 2007.

Objective: The purpose of this study was to determine the incremental cost of the management of this lead to Medicare.

Methods: Real hospital cost data in U.

Ranolazine safely decreases ventricular and atrial fibrillation in Timothy syndrome (LQT8).

Long QT eight (LQT8), otherwise known as Timothy syndrome (TS), is a genetic disorder causing hyper-activation of the L-type calcium channel Cav 1.2. This calcium load and the resultant increase in the QT interval provide the substrate for ventricular arrhythmias.

Late potential at the high ventricular septal level in a patient with Brugada: possible mechanisms and clinical implications.

The Brugada syndrome (BS) accounts for approximately 20% of cases of sudden cardiac death in patients with structurally normal hearts. The electrophysiologic basis for ST-segment elevation in the precordial electrocardiogram (ECG) leads that characterize the Brugada phenotype and its strong linkage to ventricular tachycardia (VT)/ventricular fibrillation is still a subject of controversy. Electrocardiographic manifestations of the syndrome have been attributed to one of two basic mechanisms: (1) conduction delay in the right ventricular (RV) epicardial-free wall in the region of the outflow tract or (2) premature repolarization of the RV epicardial action potential secondary to loss of the action potential dome.

Initial experience using a radiofrequency powered transseptal needle.

Introduction: The purpose of this study was to determine the safety and efficacy of using a novel radiofrequency (RF) powered transseptal needle to perform transseptal puncture (TSP).

Methods: TSP was performed in 35 consecutive patients undergoing left-sided catheter ablation (mean age = 51 years; male = 71%) using a RF powered transseptal needle (NRG, Adult Large and Standard Curve C1, 71 cm, Baylis Medical Company, Inc.).

Transseptal catheterization using a powered radiofrequency transseptal needle.

Mechanical pressure applied to a Brockenbrough needle at the fossa ovalis is the standard transseptal puncture technique. Circumstances where the fossa ovalis is thick or aneurysmal can make this method challenging. In this case, we illustrate the use of a radiofrequency powered transseptal needle to cross the fossa ovalis.