Prevalence and management of electrical lead abnormalities in cardiac implantable electronic device leads.

Background: 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. The primary outcome was ELA defined as increased capture threshold (≥2× implantation value), decreased sensing (≤0.5 implantation value), change in impedance (>50% over 3 months), or nonphysiologic potentials. A secondary outcome of device clinic utilization was also collected. Results: There were 2996 unique patients (35% female) included with 4600 leads (57% Abbott, 43% Medtronic). ELAs were observed in 135 (3%) leads, including 124 (92%) Abbott and 10 (7%) Medtronic leads (hazard ratio 9.25, P < .001). Mean follow-up was 4.5 ± 2.2 years. ELAs were associated smaller lead French size, atrial location, and Abbott leads. Lead revision was required in 28% of cases. Patients with lead abnormalities had 38% more in-clinic visits per patient year of follow-up compared with those without (P < .001). Conclusion: ELAs were more frequent in certain models, which increased rates of revision and follow-up. Identification of factors that mitigate these abnormalities to improve lead performance are required to improve care for these devices and provide efficient healthcare.

Assessment of an ECG-Based System for Localizing Ventricular Arrhythmias in Patients With Structural Heart Disease.

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. The AAOL system combines 120-ms QRS integrals of 3 leads (III, V2, V6) with pace mapping to predict VT exit/PVC origin site and projects that site onto the patient-specific electroanatomic mapping surface. VT exit/PVC origin sites were clinically identified by activation mapping and/or pace mapping. The localization error of the VT exit/PVC origin site was assessed by the distance between the clinically identified site and the estimated site. In the retrospective study of 19 patients with structural heart disease, the AAOL system achieved a mean localization accuracy of 6.5±2.6 mm for 25 induced VTs. In the prospective study with 23 patients, mean localization accuracy was 5.9±2.6 mm for 26 VT exit and PVC origin sites. There was no difference in mean localization error in epicardial sites compared with endocardial sites using the AAOL system (6.0 versus 5.8 mm, P=0.895). Conclusions The AAOL system achieved accurate localization of VT exit/PVC origin sites in patients with structural heart disease; its performance is superior to current systems, and thus, it promises to have potential clinical utility.

Remote Monitoring of Cardiovascular Implantable Electronic Devices in Canada: Survey of Patients and Device Health Care Professionals.

BACKGROUND: 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. METHODS: We surveyed 512 CIED patients and practitioners in 22 device clinics in Canada. RESULTS: Device clinic surveys highlighted significant variation and inconsistency in follow-up care for in-clinic and remote visits across and within clinics. This survey showed that funding policies and management of additional workflow are barriers to optimal use and uptake. Despite this, device clinics perceive remote follow-up as a valuable resource and an efficient way to manage patient follow-up. Patients were broadly satisfied with their CIED follow-up care but identified barriers related to coordination of care, visit logistics, and information needs. Views varied as a function of clinical or sociodemographic characteristics. Most patients (n = 228; 91%) expressed a desire to receive a phone call from their device clinic after a remote transmission has been received. CONCLUSIONS: Lack of a unified, guideline-supported approach to follow-up after CIED implant, and discrepant funding policies across jurisdictions, are significant barriers to the use of remote patient management strategies in Canada. Efforts to increase or expand use of remote follow-up must recognize these barriers and the needs of specific subgroups of patients.

INTRODUCTION: La télésurveillance sert de complément à la consultation en clinique des patients porteurs d'un dispositif cardiaque électronique implantable (DCEI) tous les 6 à 12 mois. Il est nécessaire d'optimiser la prise en charge à distance des patients porteurs de DCEI en raison de la constante augmentation des implantations de DCEI au cours de la dernière décennie. L'objectif de la présente étude était d'examiner les obstacles réels et perçus à l'utilisation des stratégies de prise en charge à distance des patients du Canada et de mieux comprendre la façon d'optimiser les modèles de soins à distance. MÉTHODES: Nous avons interrogé 512 patients porteurs de DCEI et praticiens de 22 cliniques spécialisées en DCEI du Canada. RÉSULTATS: Les enquêtes des cliniques spécialisées en DCEI ont fait ressortir la variation importante et le manque d'uniformité dans les soins de suivi lors des consultations en clinique et à distance au sein de toutes les cliniques et entre elles. Cette enquête a montré que les politiques de financement et la gestion du flux de travail supplémentaire sont les obstacles qui empêchent l'utilisation optimale et l'adoption. Malgré cela, les cliniques spécialisées en DCEI perçoivent le suivi à distance comme une ressource très utile et un moyen efficace de prendre en charge le suivi du patient. Les patients étaient dans l'ensemble satisfaits de leurs soins de suivi relatifs à leur DCEI, mais relevaient des obstacles liés à la coordination des soins, à la logistique des consultations et à leurs besoins d'information. Les points de vue variaient en fonction des caractéristiques cliniques et sociodémographiques. La plupart des patients (n = 228 ; 91 %) ont fait part de leur souhait de recevoir un appel téléphonique de leur clinique spécialisée en DCEI après la réception de la transmission à distance. CONCLUSIONS: L'absence d'une approche unifiée et fondée sur les lignes directrices qui porte sur le suivi après l'implantation de DCEI, et la divergence des politiques de financement des provinces et territoires sont des obstacles importants à l'utilisation de stratégies de prise en charge à distance des patients au Canada. Les efforts visant à accroître ou à étendre l'utilisation du suivi à distance doivent tenir compte de ces obstacles et des besoins des sous-groupes particuliers de patients.

Prospective Multicenter Assessment of a New Intraprocedural Automated System for Localizing Idiopathic Ventricular Arrhythmia Origins.

OBJECTIVES: 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). However, it has limitations, as it could not identify the site of origin in the right ventricle and relied on acquiring a complete EAM. METHODS: Twenty patients undergoing IVA catheter ablation had a 12-lead ECG recorded during clinical arrhythmia and during pacing at various locations identified on EAM geometries. The new system combined 3-lead (III, V2, and V6) 120-ms QRS integrals and patient-specific EAM geometry with pace mapping to predict the site of earliest ventricular activation. The predicted site was projected onto EAM geometry. RESULTS: Twenty-three IVA origin sites were clinically identified by activation mapping and/or pace mapping (8, right ventricle; 15, left ventricle, including 8 from the posteromedial papillary muscle, 2 from the aortic root, and 1 from the distal coronary sinus). The new system achieved a mean localization accuracy of 3.6 mm for the 23 mapped IVAs. CONCLUSIONS: The new intraprocedural AAOL system achieved accurate localization of IVA origin in ventricles and neighboring vessels, which could facilitate ablation procedures for patients with IVAs.

Remote-only monitoring for patients with cardiac implantable electronic devices: a before-and-after pilot study.

BACKGROUND: Outcomes for patients with cardiac implantable electronic devices are better when follow-up incorporates remote monitoring technology in addition to in-clinic visits. For patients with implantable devices, we sought to determine the feasibility, safety and associated health care utilization of remote-only follow-up, along with its effects on patients' quality of life and costs. METHODS: This multicentre before-and-after pilot study involved patients with new or existing pacemakers or implantable cardioverter defibrillators. The "before" phase of the study spanned the period October 2015 to February 2017; the "after" phase spanned the period October 2016 to February 2018. The exposure was remote-only follow-up in combination with Remote View, a service that facilitates access to device data, allowing device settings to be viewed remotely to facilitate remote programming. Outcomes at 12 months were feasibility (adherence to remote monitoring), safety (rate of adverse events) and health care utilization (remote and in-clinic appointments). We also assessed quality of life, using 3 validated scales, and costs, taking into account both health care system and patient costs. RESULTS: A total of 176 patients were enrolled. Adherence (defined as at least 1 successful remote transmission during follow-up) was 87% over a mean follow-up of 11.7 (standard deviation 2.2) months. There was a reduction in in-clinic visits at specialized sites among patients with both implantable defibrillators (26 v. 5, p < 0.001, n = 48) and pacemakers (42 v. 10, p < 0.001, n = 51). There was no significant change in visits to community sites for patients with defibrillators (13 v. 17, p = 0.3, n = 48). The composite rate of death, stroke, cardiovascular hospitalization and device-related hospitalization was 7% (n = 164). No adverse events were linked to the intervention. There was no change in quality-of-life scales between baseline and 12 months. Health care costs were reduced by 31% for patients with defibrillators and by 44% for those with pacemakers. INTERPRETATION: This pilot study showed the feasibility of remote-only follow-up, with no increase in adverse clinical outcomes and no effect on quality of life, but with reductions in costs and health care utilization. These results support progression to a larger-scale study of whether superior effectiveness and reduced cost can be achieved, with preservation of safety, through use of remote-only follow-up. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT02585817.

Prospective Assessment of an Automated Intraprocedural 12-Lead ECG-Based System for Localization of Early Left Ventricular Activation.

BACKGROUND: To facilitate ablation of ventricular tachycardia (VT), an automated localization system to identify the site of origin of left ventricular activation in real time using the 12-lead ECG was developed. The objective of this study was to prospectively assess its accuracy. METHODS: The automated site of origin localization system consists of 3 steps: (1) localization of ventricular segment based on population templates, (2) population-based localization within a segment, and (3) patient-specific site localization. Localization error was assessed by the distance between the known reference site and the estimated site. RESULTS: In 19 patients undergoing 21 catheter ablation procedures of scar-related VT, site of origin localization accuracy was estimated using 552 left ventricular endocardial pacing sites pooled together and 25 VT-exit sites identified by contact mapping. For the 25 VT-exit sites, localization error of the population-based localization steps was within 10 mm. Patient-specific site localization achieved accuracy of within 3.5 mm after including up to 11 pacing (training) sites. Using 3 remotes (67.8±17.0 mm from the reference VT-exit site), and then 5 close pacing sites, resulted in localization error of 7.2±4.1 mm for the 25 identified VT-exit sites. In 2 emulated clinical procedure with 2 induced VTs, the site of origin localization system achieved accuracy within 4 mm. CONCLUSIONS: In this prospective validation study, the automated localization system achieved estimated accuracy within 10 mm and could thus provide clinical utility.