Typical Atrioventricular Nodal Re-Entry Tachycardia Masquerading as Atrial Fibrillation.

We report 3 cases of irregular, narrow complex tachycardia misdiagnosed and treated for atrial fibrillation. The adenosine response, detection of recurring triple cycle length variation patterns, and pseudo-R-wave in lead V during tachycardia made us suspect typical atrioventricular nodal re-entrant tachycardia. The electrophysiology study confirmed atrioventricular nodal re-entrant tachycardia, and symptoms were resolved by slow pathway modification.

Left bundle branch pacing vs ventricular septal pacing for cardiac resynchronization therapy.

Background: The outcomes of left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP) in patients with heart failure remain to be learned.

Objective: The objective of this study was to assess the echocardiographic and clinical outcomes of LBBP, LVSP, and deep septal pacing (DSP).

Methods: This retrospective study included patients who met the criteria for cardiac resynchronization therapy (CRT) and underwent attempted LBBP in 5 Mayo centers.

Trends in the 30-year span of noninfectious cardiovascular implantable electronic device complications in Olmsted County.

Background: Cardiac implantable electronic devices (CIEDs), such as permanent pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices, alleviate morbidity and mortality in various diseases. There is a paucity of real-world data on CIED complications and trends.

Objectives: We sought to describe trends in noninfectious CIED complications over the past 3 decades in Olmsted County.

Trends in the 30-year span of Noninfectious Cardiovascular Implantable Electronic Device Complications in Olmsted County.

Background: Cardiovascular implantable electronic devices (CIEDs) such as permanent pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices alleviate morbidity and mortality in various diseases. There is a paucity of real-world data on CIED complications and trends.

Objectives: Describe trends in noninfectious CIED complications over the past three decades in Olmsted County.

Substrate Characterization and Outcomes of Catheter Ablation of Ventricular Arrhythmias in Patients With Mitral Annular Disjunction.

Background: Mitral annular disjunction (MAD) has recently been recognized as an arrhythmogenic entity. Data on the electrophysiological substrate as well as the outcomes of catheter ablation of ventricular arrhythmias in patients with MAD is limited.

Methods: Forty patients with MAD (mean age 47±15 years; 70% female) underwent catheter ablation for ventricular arrhythmias.

Trends in Cardiovascular Implantable Electronic Device Insertion Between 1988 and 2018 in Olmsted County.

Objectives: This study sought to describe trends in cardiovascular implantable electronic device (CIED) insertion over the past 3 decades in Olmsted County.

Background: Trends in CIED insertion in the United States have not been extensively studied.

Methods: The Rochester Epidemiology Project is a medical records linkage system comprising the records of all residents of Olmsted County from 1966 to the present.

Sinus rhythm heart rate increase after atrial fibrillation ablation is associated with lower risk of arrhythmia recurrence.

Background: Pulmonary vein isolation (PVI) with autonomic modulation may be more successful than PVI alone for atrial fibrillation (AF) ablation and may be signaled by changes in sinus rhythm heart rate (HR) post ablation. We sought to determine if a change in sinus rhythm HR predicted AF recurrence post PVI.

Methods: Patients who underwent AF ablation from 2000 to 2011 were included if sinus rhythm was noted on ECG within 90 days pre and 7 days post ablation.

Sustained Improvement in Diastolic Reserve Following Percutaneous Pericardiotomy in a Porcine Model of Heart Failure With Preserved Ejection Fraction.

Background: Heart failure with preserved ejection fraction is increasing in prevalence, but few effective treatments are available. Elevated left ventricular (LV) diastolic filling pressures represent a key therapeutic target. Pericardial restraint contributes to elevated LV end-diastolic pressure, and acute studies have shown that pericardiotomy attenuates the rise in LV end-diastolic pressure with volume loading.

Injectable Flexible Subcutaneous Electrode Array Technology for Electrocardiogram Monitoring Device.

Implantable cardiac monitors have undergone considerable miniaturization. However, they continue to be associated with complications such as infection, bleeding/bruising, and device extrusion or migration. In this paper, we demonstrate the feasibility of using a small, flexible, injectable, subcutaneous microelectrode-based device to record electrocardiograms (ECGs).

Long-Term Survival of Patients With Left Ventricular Noncompaction.

Background The prognosis of left ventricular noncompaction (LVNC) remains elusive despite its recognition as a clinical entity for >30 years. We sought to identify clinical and imaging characteristics and risk factors for mortality in patients with LVNC. Methods and Results 339 adults with LVNC seen between 2000 and 2016 were identified.

Burden of arrhythmia in hospitalized HIV patients.

Background: The improved life expectancy observed in patients living with human immunodeficiency virus (HIV) infection has made age-related cardiovascular complications, including arrhythmias, a growing health concern.

Hypothesis: We describe the temporal trends in frequency of various arrhythmias and assess impact of arrhythmias on hospitalized HIV patients using the Nationwide Inpatient Sample (NIS).

Methods: Data on HIV-related hospitalizations from 2005 to 2014 were obtained from the NIS database using International Classification of Diseases, 9th Revision (ICD-9) codes.

Incremental benefit of a novel signal recording system during mapping and ablation.

Aims: Current electrophysiology signal recording and mapping systems have limited dynamic range (DR) and bandwidth, which causes loss of valuable information during acquisition of cardiac signals. We evaluated a novel advanced signal processing platform with the objective to obtain and assess additional information of clinical importance.

Methods And Results: Over 10 canines, we compared intracardiac recordings within all cardiac chambers, in various rhythms, in pacing and during radiofrequency (RF) ablation across two platforms; a conventional system and the PURE EP™ [(PEP); Bio Sig Technologies, Inc.

Injectable conductive hydrogel restores conduction through ablated myocardium.

Introduction: Therapies for substrate-related arrhythmias include ablation or drugs targeted at altering conductive properties or disruption of slow zones in heterogeneous myocardium. Conductive compounds such as carbon nanotubes may provide a novel personalizable therapy for arrhythmia treatment by allowing tissue homogenization.

Methods: A nanocellulose carbon nanotube-conductive hydrogel was developed to have conduction properties similar to normal myocardium.

Feasibility of selective cardiac ventricular electroporation.

Introduction: The application of brief high voltage electrical pulses to tissue can lead to an irreversible or reversible electroporation effect in a cell-specific manner. In the management of ventricular arrhythmias, the ability to target different tissue types, specifically cardiac conduction tissue (His-Purkinje System) vs. cardiac myocardium would be advantageous.

Venoarterial Extracorporeal Membrane Oxygenation Support for Ventricular Tachycardia Ablation: A Systematic Review.

Refractory ventricular tachycardia (VT) and electrical storm are frequently associated with hemodynamic compromise requiring mechanical support. This study sought to review the current literature on the use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for hemodynamic support during VT ablation. This was a systematic review of all published literature from 2000 to 2019 evaluating patients with VT undergoing ablation with VA-ECMO support.

Trends of Cardiovascular Implantable Electronic Device Infection in 3 Decades: A Population-Based Study.

Objectives: This study assessed trends in the incidence of cardiovascular implantable electronic device (CIED) infection in the last 3 decades using a population-based records linkage study.

Background: Infection remains an important issue associated with increased implantation rate and dwell time of CIEDs.

Methods: We identified a cohort of all adults with CIEDs who resided in Olmsted County, Minnesota, from 1988 to 2015, using the medical linkage system of the Rochester Epidemiology Project.

Fundamentals of Cardiac Mapping.

To characterize cardiac activity and arrhythmias, electrophysiologists can record the electrical activity of the heart in relation to its anatomy through a process called cardiac mapping (electroanatomic mapping, EAM). A solid understanding of the basic cardiac biopotentials, called electrograms, is imperative to construct and interpret the cardiac EAM correctly. There are several mapping approaches available to the electrophysiologist, each optimized for specific arrhythmia mechanisms.

Development of a novel ablation hood to prevent systemic embolization of microbubbles and particulate emboli.

Background: Atrial fibrillation ablation results in microbubbles and particulate emboli formation. We aimed to develop and test the early feasibility of a novel ablation hood to contain microbubbles and particulate emboli with the ultimate goal of preventing systemic embolization.

Methods: In seven canines, we developed, iterated, and tested a novel retractable hood that can cover the catheter-tissue ablation site.