Publications by authors named "Amir Abdel-Wahab"
Background: The Automated Arrhythmia Origin Localization (AAOL) algorithm was developed for real-time prediction of early ventricular activation origins on a patient-specific electroanatomic (EAM) surface using a 3-lead electrocardiogram (AAOL-Surface). It has not been evaluated in 3-dimensional (3D) space (AAOL-3D), however, which may be important for predicting the arrhythmia origin from intramural or intracavity sites.
Objectives: This study sought to assess the accuracy of AAOL for localizing earliest ventricular activation in 3D space.
Article Synopsis
- There is a lack of Canadian studies analyzing the costs of catheter ablation (CA) for atrial fibrillation (AF) using patient-specific data; this study aims to fill that gap.
- A cost analysis was conducted on AF patients in Nova Scotia, comparing health care costs 2 years before and after CA, highlighting a significant decrease in hospitalizations and ER visits post-ablation.
- Although the immediate costs of the treatment were high, the overall reduction in health care usage suggests that CA could be a cost-effective solution for AF treatment in the long run.
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: 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: 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.
Article Synopsis
- Researchers developed an automated method using pace mapping to pinpoint early activation origins in the left ventricle (LV), requiring pacing from multiple sites based on the number of ECG leads used.
- They analyzed data from 1715 LV endocardial pacing sites to find the best minimal ECG lead set, using techniques like random forest regression and exhaustive search.
- The optimal leads identified (III, V1, V4 from RFR and II, V2, V6 from exhaustive search) showed similar performance in locating LV activation origins, with high accuracy achieved when more pacing sites were utilized.
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 PDFArticle Synopsis
- Remote-only follow-up for patients with cardiac implantable devices can improve outcomes, showing high adherence (87%) and reducing in-clinic visits for both pacemaker and defibrillator patients.
- The study, lasting from October 2015 to February 2018, assessed the feasibility, safety, health care utilization, and quality of life of remote monitoring, finding no significant adverse events or changes in quality of life.
- Of the 176 enrolled patients, the intervention resulted in fewer specialized clinic visits, maintaining a low composite adverse event rate of 7% without negative impacts on their overall well-being.
A virtual platform to deliver ambulatory care for patients with atrial fibrillation.
Cardiovasc 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).
Article Synopsis
- This study introduces a novel hybrid machine learning model that combines population-based and patient-specific approaches for pinpointing the origin of ventricular tachycardia using ECG data.
- The model first employs a general deep learning system trained on data from multiple patients to account for anatomical differences before adapting in real-time to a patient's specific data, improving predictions with each pacing suggestion.
- Testing on a new cohort demonstrated the model's effectiveness, achieving a precise localization error of just 5.3 mm, indicating it could significantly enhance the speed and accuracy of identifying VT targets in clinical settings.
Article Synopsis
- - The study assessed a new automated system that localizes the origin of ventricular tachycardia (VT) using a 12-lead ECG, aiming to improve the process of catheter ablation.
- - The system's accuracy was evaluated across 21 ablation procedures in 19 patients, with localization errors calculated from known reference sites to estimated sites, revealing an accuracy of 3.5 mm with patient-specific adjustments.
- - The results indicated that the localization system achieved an overall accuracy within 10 mm, suggesting it has potential clinical applications for managing VT.
Article Synopsis
- The Canadian Cardiovascular Society's position statement addresses managing sustained ventricular tachycardia (VT) and ventricular fibrillation (VF) in patients with structural heart disease, which is increasingly common due to better care and survival rates.
- It covers both acute and long-term treatment strategies, highlighting unique care considerations such as initial evaluations, acute therapies, chronic suppressive options, and implantable defibrillator programming.
- The statement is directed at health professionals involved in the care of SHD patients, providing recommendations for delivering optimal patient care.
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).
Background: Catheter ablation is effective for eliminating most drug-refractory ventricular arrhythmias (VA). However, a major reason for procedural failure is arrhythmia originating deep within the myocardium where it is inaccessible to conventional endocardial or epicardial approaches. Affected patients have limited therapeutic options.
View Article and Find Full Text PDFWe have previously developed an automated localization method based on multiple linear regression (MLR) model to estimate the activation origin on a generic left-ventricular (LV) endocardial surface in real time from the 12-lead ECG. The present study sought to investigate whether machine learning-namely, random-forest regression (RFR) and support-vector regression (SVR)-can improve the localization accuracy compared to MLR. For 38 patients the 12-lead ECG was acquired during LV endocardial pacing at 1012 sites with known coordinates exported from an electroanatomic mapping system; each pacing site was then registered to a generic LV endocardial surface subdivided into 16 segments tessellated into 238 triangles.
View Article and Find Full Text PDFBackground: The comparative efficacy of antiarrhythmic drug (AAD) therapy vs ventricular tachycardia (VT) ablation in arrhythmogenic right ventricular cardiomyopathy (ARVC) is unknown.
Objective: We compared outcomes of AAD and/or β-blocker (BB) therapy with those of VT ablation (with AAD/BB) in patients with ARVC who had recurrent VT.
Methods: In a multicenter retrospective study, 110 patients with ARVC (mean age 38 ± 17 years; 91[83%] men) with a minimum of 3 VT episodes were included; 77 (70%) were initially treated with AAD/BB and 32 (29%) underwent ablation.
Background: Rapid accurate localization of the site of ventricular activation origin during catheter ablation for ventricular arrhythmias could facilitate the procedure. Electrocardiographic imaging (ECGI) using large lead sets can localize the origin of ventricular activation. We have developed an automated method to identify sites of early ventricular activation in real time using the 12-lead ECG.
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