Twiddler Syndrome without Lead Dislodgment Discovered by Remote Monitoring.

Twiddler syndrome is an uncommon yet dangerous phenomenon usually resulting in lead displacement with loss of capture of cardiac implantable electronic devices. In this case report, we present an interesting case of Twiddler syndrome without lead dislodgment which was detected by an alert triggered by an increase in impedance on remote monitoring.

Ventricular Arrhythmia in Septal and Apical Hypertrophic Cardiomyopathy: The French-Canadian Experience.

Apical hypertrophic cardiomyopathy (aHCM) is thought to have a more benign clinical course compared to septal HCM (sHCM), but most data have been derived from Asian cohorts. Comparative data on clinical outcome in Caucasian aHCM cohorts are scarce, and the results are conflicting. The aim of this study was to estimate the prevalence and outcome of aHCM in French-Canadians of Caucasian descent.

Findings of remote monitoring of implantable cardioverter defibrillators during the COVID-19 pandemic.

Background: Monitoring of cardiac implantable electronic devices was highly impacted by the COVID-19 pandemic considering the high volume of in-person visits for regular follow-up. Recent recommendations highlight the important role of remote monitoring to prevent exposure to the virus. This study compared remote monitoring of implantable cardioverter defibrillators (ICDs) in patients whose in-person annual visit was substituted for a remote monitoring session with patients who were already scheduled for a remote monitoring session.

Driving Restrictions and Early Arrhythmias in Patients Receiving a Primary-Prevention Implantable Cardioverter-Defibrillator (DREAM-ICD) Study.

Background: Current guidelines recommend 4 weeks of private driving restriction after implantation of a primary-prevention implantable cardioverter-defibrillator (ICD). These driving restrictions result in significant inconvenience and social implications. Advances in medical treatment and ICD programming have lowered the overall rate of device therapies.

A Novel Wearable Device for Continuous Ambulatory ECG Recording: Proof of Concept and Assessment of Signal Quality.

Diagnosis of arrhythmic disorders is challenging because of their short-lasting, intermittent character. Conventional technologies of noninvasive ambulatory rhythm monitoring are limited by modest sensitivity. We present a novel form of wearable electrocardiogram (ECG) sensors providing an alternative tool for long-term rhythm monitoring with the potential of increased sensitivity to detect intermittent or subclinical arrhythmia.

Validation of a novel single lead ambulatory ECG monitor - Cardiostat™ - Compared to a standard ECG Holter monitoring.

Background: Cardiostat™ is a single lead ambulatory ECG monitor. Recording is made through 2 electrodes positioned in a lead 1-like configuration. We first validated its accuracy for atrial fibrillation detection compared to a 12-lead ECG.

Cardiac Implantable Electronic Device Infection: Detailed Analysis of Cost Implications.

Background: Infections of cardiac implantable electronic devices (CIED) are associated with significant morbidity and mortality. Despite many preventive measures, this condition is associated with significant costs for the health care system.

Methods: We retrospectively analyzed all infection cases referred for lead extraction at a single university hospital over 1 year (2015-2016).

Clinical performance of different DF-4 implantable cardioverter defibrillator leads.

Introduction: Implantable cardioverter-defibrillator (ICD) DF-4 connectors have been introduced to facilitate defibrillator lead connection and to reduce the size of device header. There are limited data regarding the overall performance of those leads and no comparison between different ICD DF-4 leads.

Methods: This is a cohort study of consecutive patients implanted with ICD DF-4 lead system at one University Centre between October 2010 and February 2015.

Feasibility of extravascular pacing with a novel substernal electrode configuration: The Substernal Pacing Acute Clinical Evaluation study.

Background: Subcutaneous implantable cardioverter-defibrillators provide an alternative to transvenous defibrillation but require higher shock outputs and offer no antitachycardia pacing. The Substernal Pacing Acute Clinical Evaluation (SPACE) study evaluated the feasibility of pacing from an extravascular substernal location.

Objectives: The primary purpose of the SPACE study was to characterize pacing from the substernal space.

Canadian Cardiovascular Society/Canadian Heart Rhythm Society 2016 Implantable Cardioverter-Defibrillator Guidelines.

Sudden cardiac death is a major public health issue in Canada. However, despite the overwhelming evidence to support the use of implantable cardioverter defibrillators (ICDs) in the prevention of cardiac death there remains significant variability in implantation rates across Canada. Since the most recent Canadian Cardiovascular Society position statement on ICD use in Canada in 2005, there has been a plethora of new scientific information to assist physicians in their discussions with patients considered for ICD implantation to prevent sudden cardiac death due to ventricular arrhythmias.

Left ventricular three-dimensional quadripolar lead acute clinical study: the LILAC study.

Aims: This multicenter acute clinical study was designed to verify novel three-dimensional (3D) quadripolar lead designs that can achieve ≤2.5 V average pacing capture threshold (PCT) not only at the apex, but also at the base of the left ventricle with phrenic nerve stimulation (PNS) avoidance for cardiac resynchronization.

Methods: During the implant procedure, up to two different left ventricular investigational leads were introduced and tested in the same target coronary vein based on the coronary sinus venogram in a wedged and unwedged position.

Longitudinal follow-up of Riata leads reveals high annual incidence of new conductor externalization and electrical failure.

Background And Purpose: Riata(TM) defibrillation leads are susceptible to conductor externalization. The point prevalence of insulation defect in Riata(TM) leads is up to 33 %, but prospective data concerning incidence of new lead abnormalities are lacking. The purpose of our study was to determine the annual incidence of new conductor externalizations and electrical lead failure.

PA/Lateral chest X-ray is equivalent to cine-fluoroscopy for the detection of conductor externalization in defibrillation leads.

Background: Riata™ and Riata ST defibrillation leads (St. Jude Medical, Sylmar, CA, USA) are susceptible to insulation defects with conductor externalization. Cine-fluoroscopy is considered to be the gold standard for the documentation of insulation defects, but similar detection rates have been reported for posterior-anterior (PA)/lateral chest x-ray (CXR) with zooming.

A multicenter study of shock pathways for subcutaneous implantable defibrillators.

Introduction: A purely subcutaneous implantable cardioverter defibrillator (ICD) requires higher energy but may be an effective alternative to transvenous ICDs to deliver lifesaving therapies.

Objective: To identify combinations of anteroposterior subcutaneous shock pathways and waveforms with defibrillation efficacy comparable to transvenous ICDs.

Methods: Defibrillation testing was performed in 141 patients temporarily implanted with an active can emulator and subcutaneous coil electrodes.

Selective left ventricular sensing lead implantation to overcome undersensing of ventricular fibrillation during implantable cardioverter defibrillator implantation.

Accurate sensing of malignant arrhythmia is critical for the appropriate delivery of therapy from implantable cardioverter defibrillators, and undersensing of ventricular tachyarrhythmias can have catastrophic consequences. Here, we present an unusual case of ventricular fibrillation undersensing from the right ventricular lead at multiple different implantation sites because of very low amplitude voltage signals during induced ventricular fibrillation. A left ventricular sensing electrode was implanted to allow correct sensing and therapy delivery.

Detection of high incidence of Riata lead breaches by systematic postero-anterior and lateral chest X-ray in a large cohort.

Aims: Insulation breaches with externalization of conductor cables have been described for St-Jude Medical Riata™ defibrillation leads. Published data on the incidence of Riata lead abnormalities are quite heterogeneous. The objective of this study was to estimate systematically the prevalence of lead abnormalities using a postero-anterior (PA) and lateral chest X-ray (CXR).

Usefulness of fluorine-18 positron emission tomography/computed tomography for identification of cardiovascular implantable electronic device infections.

Objectives: This study evaluated the usefulness of fluorodesoxyglucose marked by fluorine-18 ((18)F-FDG) positron emission tomography (PET) and computed tomography (CT) in patients with suspected cardiovascular implantable electronic device (CIED) infection.

Background: CIED infection is sometimes challenging to diagnose. Because extraction is associated with significant morbidity/mortality, new imaging modalities to confirm the infection and its dissemination would be of clinical value.

Prospective comparison between conventional transseptal puncture and transseptal needle puncture with radiofrequency energy.

Purpose: Patients undergoing left atrial ablation require transseptal puncture, which can be challenging, even for experienced physicians. This study compared the efficacy and safety of radiofrequency (RF) energy transseptal punctures to conventional approach.

Methods: Patients requiring transseptal puncture for left atrial access were included using either conventional approach or the NRG™ RF transseptal needle as first attempt.

Cardiac arrest as a major complication of bilateral cervico-dorsal sympathectomy.

Severe palmar and/or axillary hyperhidrosis can be socially and psychologically very disturbing. We present a case of a patient who suffered from a 43 s asystolic cardiac arrest the night following a second contralateral thoracoscopic T(2)-T(3) sympathectomy for severe axillary and truncal hyperhidrosis. The cardiovascular effects of cervico-dorsal sympathectomy will be reviewed.

The Brugada syndrome in Canada: a unique French-Canadian experience.

Unlabelled: The Brugada syndrome (BS) is a clinical entity involving cardiac sodium channelopathy, typical electrocardiogram (ECG) changes and predisposition to ventricular arrhythmia. This syndrome is mainly recognized by specialized cardiologists and electrophysiologists. Data regarding BS largely come from multicentre registries or Asian countries.

Catheter ablation for cardiac arrhythmias: a 14-year experience with 5330 consecutive patients at the Quebec Heart Institute, Laval Hospital.

Background: Catheter ablation is a curative treatment with excellent success and minimal complication rates for patients with supraventricular or ventricular arrhythmias.

Methods: The acute outcomes and complications of all catheter ablation procedures for supraventricular and ventricular arrhythmias performed at the Quebec Heart Institute (Sainte-Foy, Quebec) during a 14-year period from January 1, 1993, to December 31, 2006, were prospectively assessed. The ablation procedures were classified according to the arrhythmias induced using standard electrophysiological techniques and definitions.

Reduced incidence of vagally induced atrial fibrillation and expression levels of connexins by n-3 polyunsaturated fatty acids in dogs.

Objectives: This open-label canine study assessed whether n-3 polyunsaturated fatty acids (PUFAs) prevent vagally induced atrial fibrillation (AF) and influence atrial tissue expression levels of connexins (CXs).

Background: n-3 polyunsaturated fatty acids in fish oils protect against sudden cardiac death and reduce postoperative AF. Changes in spatial organization of gap junctions or cellular CX levels have been linked to arrhythmogenesis.

Usefulness of transesophageal echocardiography in the isolation of pulmonary veins in the treatment of atrial fibrillation.

Background: New imaging strategies for atrial fibrillation (AF) ablation should enhance the safety of this technique. The role of transesophageal echocardiography (TEE) in this setting has not been prospectively evaluated.

Methods: Under general anesthesia, 85 patients underwent TEE-guided AF ablation.