Fibroblasts in heart scar tissue directly regulate cardiac excitability and arrhythmogenesis.

After heart injury, dead heart muscle is replaced by scar tissue. Fibroblasts can electrically couple with myocytes, and changes in fibroblast membrane potential can lead to myocyte excitability, which suggests that fibroblast-myocyte coupling in scar tissue may be responsible for arrhythmogenesis. However, the physiologic relevance of electrical coupling of myocytes and fibroblasts and its impact on cardiac excitability in vivo have never been demonstrated.

Massive Air Embolism During Atrial Fibrillation Ablation: Averting Disaster in a Time of Crisis.

A 62-year-old male with symptomatic persistent atrial fibrillation underwent radiofrequency catheter ablation. During exchange of the saline irrigation bag, the patient developed sudden hypotension and bradycardia and was found to have a massive air embolism. Air was successfully aspirated with catheters, and the patient did not suffer any permanent sequelae.

Arrhythmic Risk Profile and Outcomes of Patients Undergoing Cardiac Sympathetic Denervation for Recurrent Monomorphic Ventricular Tachycardia After Ablation.

Background Cardiac sympathetic denervation (CSD) has been used as a bailout strategy for refractory ventricular tachycardia (VT). Risk of VT recurrence in patients with scar-related monomorphic VT referred for CSD and the extent to which CSD can modify this risk is unknown. We aimed to quantify arrhythmia recurrence risk and impact of CSD in this population.

Non-invasive stereotactic body radiation therapy for refractory ventricular arrhythmias: an institutional experience.

Background: Initial studies have reported excellent safety and efficacy for stereotactic body radiation therapy (SBRT) in patients with refractory ventricular tachycardia (VT).

Methods: This is a single-center retrospective analysis of eight consecutive patients who underwent SBRT for refractory, scar-related VT. The anatomic target for radioablation was defined based on surface 12-lead ECG VT morphology, cardiac magnetic resonance imaging, and electroanatomic mapping data when available.

Recurrent ventricular tachycardia after cardiac sympathetic denervation: Prolonged cycle length with improved hemodynamic tolerance and ablation outcomes.

Introduction: Cardiac sympathetic denervation (CSD) is utilized for the management of ventricular tachycardia (VT) in structural heart disease when refractory to radiofrequency ablation (RFA) or when patient/VT characteristics are not conducive to RFA.

Methods: We studied consecutive patients who underwent CSD at our institution from 2009 to 2018 with VT requiring repeat RFA post-CSD. Patient demographics, VT/procedural characteristics, and outcomes were assessed.

Renal denervation as adjunctive therapy to cardiac sympathetic denervation for ablation refractory ventricular tachycardia.

Background: Autonomic modulation is finding an increasing role in the treatment of ventricular arrhythmias. Renal denervation (RDN) has been described as a treatment modality for refractory ventricular tachycardia (VT) in case series.

Objective: The purpose of this study was to evaluate RDN as an adjunctive therapy to cardiac sympathetic denervation (CSD) for ablation refractory VT.

Update on prevention and treatment of sudden cardiac arrest.

Sudden cardiac arrest is the leading cause of cardiovascular mortality, posing a substantial public health burden. The incidence and epidemiology of sudden death are a function of age, with primary arrhythmia syndromes and inherited cardiomyopathies representing the predominant causes in younger patients, while coronary artery disease being the leading etiology in those who are 35 years of age and older. Internal cardioverter defibrillators remain the mainstay of primary and secondary prevention of sudden cardiac arrest.

Hybrid surgical vs percutaneous access epicardial ventricular tachycardia ablation.

Background: There is limited experience of surgical epicardial access in the contemporary era of ventricular tachycardia ablation after cardiac surgery.

Objectives: The purpose of this study was to describe our institutional experience with surgical epicardial access and the influence of surgical approach and compare outcomes with those of a propensity-matched percutaneous epicardial access control group.

Methods: We performed a retrospective study of consecutive surgical epicardial ventricular tachycardia (VT) ablation cases from a single center.

Increased Nonalternans Repolarization Variability Precedes Ventricular Tachycardia Onset in Patients with Implantable Defibrillators.

Backround: T-wave alternans (TWA) is associated with ventricular tachycardia (VT). Nonalternans repolarization variability (NARV) precedes VT in certain experimental models, but its link to clinical arrhythmia is unproven. This study was conducted to determine if NARV increases prior to VT in patients with implantable cardioverter defibrillators (ICDs).