Percutaneous left stellate ganglion block for refractory ventricular tachycardia in structural heart disease: our single-centre experience.

Introduction: When electrical storm (ES) is amenable to neither antiarrhythmic drugs, nor deep sedation or catheter ablation, autonomic modulation may be considered. We report our experience with percutaneous left stellate ganglion block (PSGB) to temporarily suppress refractory ventricular arrhythmia (VA) in patients with structural heart disease.

Methods: A retrospective analysis was performed at our institution of patients with structural heart disease and an implantable cardioverter defibrillator (ICD) who had undergone PSGB for refractory VA between January 2018 and October 2021.

Cardioversion strategy impacts rate control during recurrences in patients with paroxysmal atrial fibrillation: A subanalysis of the RACE 7 ACWAS trial.

Background: In the Rate Control versus Electrical Cardioversion Trial 7-Acute Cardioversion versus Wait and See, patients with recent-onset atrial fibrillation (AF) were randomized to either early or delayed cardioversion.

Aim: This prespecified sub-analysis aimed to evaluate heart rate during AF recurrences after an emergency department (ED) visit identified by an electrocardiogram (ECG)-based handheld device.

Methods: After the ED visit, included patients (n = 437) were asked to use an ECG-based handheld device to monitor for recurrences during the 4-week follow-up period.

Mobile health adherence for the detection of recurrent recent-onset atrial fibrillation.

Objective: The Rate Control versus Electrical Cardioversion Trial 7-Acute Cardioversion versus Wait and See trial compared early to delayed cardioversion for patients with recent-onset symptomatic atrial fibrillation (AF). This study aims to evaluate the adherence to a 4-week mobile health (mHealth) prescription to detect AF recurrences after an emergency department visit.

Methods: After the emergency department visit, the 437 included patients, irrespective of randomisation arm (early or delayed cardioversion), were asked to record heart rate and rhythm for 1 min three times daily and in case of symptoms by an electrocardiography-based handheld device for 4 weeks (if available).

Shorter RSPV cryoapplications result in less phrenic nerve injury and similar 1-year freedom from atrial fibrillation.

Background: In the 123-study, we prospectively assessed, in a randomized fashion, the minimal cryoballoon application time necessary to achieve pulmonary vein (PV) isolation (PVI) in patients with paroxysmal atrial fibrillation (AF) with the aim to reduce complications by shortening the application duration. The first results of this study demonstrated that shortened cryoballoon applications (<2 minutes) resulted in less phrenic nerve injury (PNI) without compromising acute isolation efficacy for the right PVs. We now report the 1-year follow-up results regarding safety and efficacy of shorter cryoballoon applications.

Early or Delayed Cardioversion in Recent-Onset Atrial Fibrillation.

Background: Patients with recent-onset atrial fibrillation commonly undergo immediate restoration of sinus rhythm by pharmacologic or electrical cardioversion. However, whether immediate restoration of sinus rhythm is necessary is not known, since atrial fibrillation often terminates spontaneously.

Methods: In a multicenter, randomized, open-label, noninferiority trial, we randomly assigned patients with hemodynamically stable, recent-onset (<36 hours), symptomatic atrial fibrillation in the emergency department to be treated with a wait-and-see approach (delayed-cardioversion group) or early cardioversion.

Shorter cryoballoon applications times do effect efficacy but result in less phrenic nerve injury: Results of the randomized 123 study.

Background: The second-generation cryoballoon significantly improves outcome of pulmonary vein isolation (PVI) but may cause more complications than the first generation. Currently, no consensus regarding optimal cryoballoon application time exists. The 123-study aimed to assess the minimal cryoballoon application duration necessary to achieve PVI (primary endpoint) and the effect of application duration on prevention of phrenic nerve injury (PNI).

Non-sustained ventricular tachycardia in patients with congenital heart disease: An important sign?

Background: Sustained ventricular tachycardia (susVT) and ventricular fibrillation (VF) are observed in adult patients with congenital heart disease (CHD). These dysrhythmias may be preceded by non-sustained ventricular tachycardia (NSVT). The aims of this study are to examine the 1] time course of ventricular tachyarrhythmia (VTA) in a large cohort of patients with various CHDs and 2] the development of susVT/VF after NSVT.

Time Course of Atrial Fibrillation in Patients With Congenital Heart Defects.

Background: The incidence of atrial fibrillation (AF) is rising in the aging patients with congenital heart defects (CHD). However, studies reporting on AF in patients with CHD are scarce. The aim of this multicenter study was to examine in a large cohort of patients with a variety of CHD: (1) the age of onset and initial treatment of AF, coexistence of atrial tachyarrhythmia and (2) progression of paroxysmal to (long-standing) persistent/permanent AF during long-term follow-up.

Performance of an external transtelephonic loop recorder for automated detection of paroxysmal atrial fibrillation.

Background: Although atrial fibrillation (AF) is the most commonly encountered arrhythmia, some of the properties make its detection challenging. In daily practice, underdiagnosis can lead to less effective treatment in prevention of stroke. Based on data from studies on treatment of AF, more intensive follow-up strategies, including 7-day Holter recording, 30-day event recording, and even implantable cardiac monitoring devices, are suggested.

High failure rate of the 5 French Sorin Hepta 4B pacemaker lead.

Aims: The 5 French Sorin Hepta 4B lead is a bipolar transvenous pacemaker lead with a passive fixation mechanism. From 2003 to 2008, a total of 98 Sorin Hepta 4B right ventricular pacemaker leads were implanted in our hospital. We observed an unexpected high failure rate of this pacemaker lead.

Conductor externalization of the Riata internal cardioverter defibrillator lead: tip of the iceberg? Report of three cases and review of literature.

Aims: Recently, concerns about St Jude's Riata lead family have come to light. We present three cases of patients with Riata internal cardioverter defibrillator (ICD) leads with externalized conductors.

Methods And Results: All patients had the same insulation defect, with externalized conductors, but differed in presentation and symptoms.

Ventricular remodelling is a prerequisite for the induction of dofetilide-induced torsade de pointes arrhythmias in the anaesthetized, complete atrio-ventricular-block dog.

Introduction: A number of predisposing factors have been suggested to be contributing to drug-induced torsade de pointes (TdP) arrhythmias: short-long-short (SLS) sequence, bradycardia, timing of drug administration, anaesthesia, ventricular remodelling, and altered ventricular activation due to ventricular ectopic beats (SLS) or idioventricular rhythm (IVR). Chronic atrio-ventricular (AV)-block (CAVB) dogs are susceptible to dofetilide-induced TdP.

Methods And Results: In 32 anaesthetized animals, the relevance of ventricular remodelling for TdP susceptibility was studied by dofetilide [0.

Paradoxical increase of stimulus to atrium interval despite His-bundle capture during para-Hisian pacing.

Para-Hisian pacing at high output simultaneously captures the His bundle or proximal right bundle, as well as the adjacent ventricular myocardium. At lower output, direct His-bundle, or right-bundle, capture is lost which causes an increase in the stimulus to atrium interval. We describe a case with an increment of 68 ms with capture of the His bundle.

Provocation of silence.

We describe the development of a Brugada ECG together with sinus- and ventricular arrest after intravenous flecainide for atrial fibrillation in a patient in whom eventually a SCN5a mutation was identified. Unrecognized SCN5A mutations could underlie class IC-induced sinus arrest and conduction defects in some patients.

Apical rotating flow and right ventricular cerebral compression.

A 59-year-old male was admitted to the emergency room with signs of heart failure. The echocardiogram showed an extensive apical infarction with large mobile thrombi in the left ventricle. Doppler examination demonstrated apical rotating flow.

Proarrhythmic electrical remodelling is associated with increased beat-to-beat variability of repolarisation.

Objective: Acquired long-QT syndrome in combination with increased beat-to-beat variability of repolarisation duration (BVR) is associated with lethal torsades de pointes arrhythmias (TdP) in dogs with remodelled heart after atrioventricular block (AVB). We evaluated the relative contributions of bradycardia and ventricular remodelling to proarrhythmic BVR with and without pharmacological I(Kr) block in order to identify the individual at risk.

Methods: Three groups of dogs were used: sinus rhythm dogs (n = 12), dogs with acute AVB (n = 8), and dogs with >3 weeks chronic AVB (n = 27).

Sudden cardiac death in dogs with remodeled hearts is associated with larger beat-to-beat variability of repolarization.

Increased proarrhythmia in dogs with chronic AV block (AVB) has been explained by ventricular remodeling causing a decrease in repolarization reserve. Beat-to-beat variability of repolarization (BVR) has been suggested to reflect repolarization reserve, in which high variability represents diminished reserve and larger propensity for repolarization-dependent ventricular arrhythmia. A subset of chronic AVB dogs (10%) suffers sudden cardiac death (SCD).

Asynchronous development of electrical remodeling and cardiac hypertrophy in the complete AV block dog.

Objective: Left ventricular hypertrophy has been associated with the prolongation of QT-time, and an increased risk of ventricular arrhythmias. The renin angiotensin system has been implicated in the development of ventricular hypertrophy. At 5 weeks complete AV block (CAVB) in the dog, there is: (1) biventricular hypertrophy associated with a transient activation of components of the renin angiotensin system, (2) increased APD, more pronounced in the left than in the right ventricle leading to spatial dispersion of repolarization, and (3) enhanced susceptibility to drug-induced torsade de pointes arrhythmias.

Probing the contribution of IKs to canine ventricular repolarization: key role for beta-adrenergic receptor stimulation.

Background: In large mammals and humans, the contribution of IKs to ventricular repolarization is still incompletely understood.

Methods And Results: In vivo and cellular electrophysiological experiments were conducted to study IKs in canine ventricular repolarization. In conscious dogs, administration of the selective IKs blocker HMR 1556 (3, 10, or 30 mg/kg PO) caused substantial dose-dependent QT prolongations with broad-based T waves.