Background: Patients with ventricular tachycardia and ischemic cardiomyopathy are at high risk for adverse outcomes. Catheter ablation is commonly used when antiarrhythmic drugs do not suppress ventricular tachycardia. Whether catheter ablation is more effective than antiarrhythmic drugs as a first-line therapy in patients with ventricular tachycardia is uncertain.
View Article and Find Full Text PDFBackground: Previous registries have shown a younger average age at presentation with cardiovascular diseases in the Middle East (ME), but no study has examined atrioventricular block (AVB). Moreover, these comparisons are confounded by younger populations in the ME. We sought to describe the average age at presentation with AVB in ME and quantify the effect of being from ME, adjusted for the overall younger population.
View Article and Find Full Text PDFBackground: Electrical lead abnormalities (ELAs) can result in device malfunction, leading to significant morbidity in patients with cardiac implantable electronic devices (CIEDs).
Objective: We sought to determine the prevalence and management of ELAs in patients with CIEDs.
Methods: This was a retrospective cohort study of patients implanted with a CIED between 2012 and 2019 at a tertiary care center.
We previously developed a non-invasive approach to localize the site of early left ventricular activation origin in real time using 12-lead ECG, and to project the predicted site onto a generic LV endocardial surface using the smallest angle between two vectors algorithm (SA). To improve the localization accuracy of the non-invasive approach by utilizing the K-nearest neighbors algorithm (KNN) to reduce projection errors. Two datasets were used.
View Article and Find Full Text PDFBackground: Implantable cardioverter-defibrillators (ICDs) reduce mortality in patients with reduced left ventricular ejection fraction (LVEF). We investigated sex disparities in a contemporary Canadian population for utilization of primary prevention ICDs.
Methods: This was a retrospective cohort study on patients with reduced LVEF admitted to hospitals from 2010 to 2020 in Nova Scotia (population = 971,935).
Background: Surface ECG is a useful tool to guide mapping of focal atrial tachycardia (AT).
Objectives: We aimed to construct 12-lead ECG templates for P-wave morphology (PWM) during endocardial pacing from different sites in both atria in patients with no apparent structural heart disease (derivation cohort), with the goal of creating a localization algorithm, which could subsequently be validated in a cohort of patients undergoing catheter ablation of focal AT (validation cohort).
Methods: We prospectively enrolled consecutive patients who underwent electrophysiology study, had no structural heart disease and no atrial enlargement.
Background: We previously reported feasibility of irrigated needle ablation (INA) with a retractable 27-G end-hole needle catheter to treat nonendocardial ventricular arrhythmia substrate, an important cause of ablation failure.
Objectives: The purpose of this study was to report outcomes and complications in our entire INA-treated population.
Methods: Patients with recurrent sustained monomorphic ventricular tachycardia (VT) or high-density premature ventricular contractions (PVCs) despite radiofrequency ablation were prospectively enrolled at 4 centers.
Background We have previously developed an intraprocedural automatic arrhythmia-origin localization (AAOL) system to identify idiopathic ventricular arrhythmia origins in real time using a 3-lead ECG. The objective was to assess the localization accuracy of ventricular tachycardia (VT) exit and premature ventricular contraction (PVC) origin sites in patients with structural heart disease using the AAOL system. Methods and Results In retrospective and prospective case series studies, a total of 42 patients who underwent VT/PVC ablation in the setting of structural heart disease were recruited at 2 different centers.
View Article and Find Full Text PDFBackground: Remote monitoring is used to supplement in-clinic follow-up for patients with cardiac implantable electronic devices (CIEDs) every 6-12 months. There is a need to optimize remote management for CIEDs because of the consistent increases in CIED implants over the past decade. The objective of this study was to investigate real and perceived barriers to the use of remote patient management strategies in Canada and to better understand how remote models of care can be optimized.
View Article and Find Full Text PDFObjectives: The objective of this study was to present a new system, the Automatic Arrhythmia Origin Localization (AAOL) system, which used incomplete electroanatomic mapping (EAM) for localization of idiopathic ventricular arrhythmia (IVA) origin on the patient-specific geometry of left ventricular, right ventricular, and neighboring vessels. The study assessed the accuracy of the system in localizing IVA source sites on cardiac structures where pace mapping is challenging.
Background: An intraprocedural automated site of origin localization system was previously developed to identify the origin of early left ventricular activation by using 12-lead electrocardiograms (ECGs).
Introduction: We recently developed two noninvasive methodologies to help guide VT ablation: population-derived automated VT exit localization (PAVEL) and virtual-heart arrhythmia ablation targeting (VAAT). We hypothesized that while very different in their nature, limitations, and type of ablation targets (substrate-based vs. clinical VT), the image-based VAAT and the ECG-based PAVEL technologies would be spatially concordant in their predictions.
View Article and Find Full Text PDFCardiovasc Digit Health J
February 2021
Background: There are little data on the use of virtual care for patients with arrhythmia. We evaluated a virtual clinic platform, in conjunction with specialist care, for patients with symptomatic atrial fibrillation (AF).
Methods: This was a prospective, observational cohort study evaluating an online educational and treatment platform, with a randomized sub-study examining the use of an ambulatory single-lead electrocardiogram heart monitor (AHM).
Background: There is clear evidence that patients with prior myocardial infarction and a reduced ejection fraction benefit from implantation of a cardioverter-defibrillator (ICD). It is unclear whether this benefit is altered by whether or not revascularization is performed prior to ICD implantation.
Methods: This was a retrospective cohort study following patients who underwent ICD implantation from 2002 to 2014.
Background: Prior studies have demonstrated an association between appropriate implantable cardioverter defibrillator (ICD) shocks and mortality in clinical trials. The effect of shock burden on heart failure and mortality has not been previously studied in a large population-based cohort.
Methods: The cohort was derived using a comprehensive prospective ICD registry in the province of Nova Scotia with a mean follow-up of 4 ± 2.
Background: Cardiac resynchronization therapy (CRT) is effective in treating advanced heart failure (HF), but data describing benefits and long-term outcomes for upgrades from a preexisting device are limited. This study sought to compare long-term outcomes in de novo CRT implants with those eligible for CRT with a prior device.
Methods: This is a retrospective cohort study using data from a provincial registry (2002-2015).
Background: To facilitate catheter ablation of ventricular tachycardia (VT), we previously developed an automated method to identify sources of left ventricular (LV) activation in real time using 12-lead electrocardiography (ECG), the accuracy of which depends on acquisition of a complete electroanatomic (EA) map.
Objective: The purpose of this study was to assess the feasibility of using a registered cardiac computed tomogram (CT) rather than an EA map to permit real-time localization and avoid errors introduced by incomplete maps.
Methods: Before LV VT ablation, 10 patients underwent CT imaging and 3-dimensional reconstruction of the cardiac surface to create a triangle mesh surface, which was registered to the EA map during the procedure and imported into custom localization software.
Background: Cardiac rehabilitation (CR) intervention programs are currently not part of management in patients with atrial fibrillation (AF). We sought to determine the effect of CR compared with a specialized AF clinic (AFC) and usual care on outcomes in patients with AF.
Methods: This was a single-centre retrospective cohort study that was carried out using 3 databases: the Hearts in Motion database (2010-2014), prospectively collected data in an AFC (2011-2014), and a retrospective chart review for patients in usual care (2009-2012).