Temperature to time Catch-Up: a novel procedural endpoint to predict durable pulmonary vein isolation after cryoballoon ablation of paroxysmal atrial fibrillation.

Background: Cryoballoon ablation is a widely used single-shot technique for pulmonary vein isolation (PVI) in the treatment of paroxysmal atrial fibrillation (AF). Procedural endpoints ensuring maximal PVI durability are important.

Objective: To assess the performance of cryoablation procedural markers to predict long-term PVI.

Predictors of Atrial Fibrillation in Patients with Embolic Stroke of Unknown Etiology and Implantable Loop Recorders-Further Insights of the TRACK AF Study on the Role of ECG and Echocardiography.

-Electrocardiography (ECG) and echocardiographic left atrial (LA) parameters may be helpful to assess the risk of atrial fibrillation (AF) in embolic stroke of unknown etiology (ESUS) and could therefore guide intensity of ECG monitoring. -1153 consecutive patients with ischemic stroke or transient ischemic attack (TIA) were analyzed. An internal loop recorder (ILR) was implanted in 104 consecutive patients with ESUS.

Left Atrial Posterior Wall Isolation with Pulsed Field Ablation in Persistent Atrial Fibrillation.

Background: Left atrial posterior wall isolation (LAPWI) may improve rhythm control in addition to pulmonary vein isolation (PVI) in persistent atrial fibrillation (persAF) patients undergoing catheter ablation (CA). However, LAPWI may be challenging when using thermal energy sources.

Objective: This study aimed to investigate the efficacy and safety of LAPWI performed by non-thermal pulsed field ablation (PFA) in CA for persAF.

Outcome of patients with idiopathic ventricular fibrillation and correlation with ECG markers of early repolarization.

Background: Early repolarization pattern (ERP) has been associated with idiopathic ventricular fibrillation (IVF) and with cardiovascular mortality in the general population. As there is limited data about long- term outcome of IVF, the aim of our study was to observe ventricular arrhythmia (VA) recurrences in these patients and to identify a possible correlation of VA with ECG markers of early repolarization.

Methods And Results: We investigated 56 consecutive IVF patients who received an implantable cardioverter-defibrillator for secondary prevention.

Bradycardia in Patients with Subcutaneous Implantable Defibrillators-An Overestimated Problem? Experience from a Large Tertiary Centre and a Review of the Literature.

Background: The subcutaneous ICD (S-ICD) has developed as a valuable alternative to transvenous implantable cardioverter defibrillator (ICD) systems. However there are certain peculiarities which are immanent to the S-ICD and may limit its use. Besides oversensing the main issue is the missing option for antibradycardia pacing.

Electrophysiological Safety Profile of Antiestrogenic Therapies in the Isolated Rabbit Heart.

Introduction: Hormone-mediated therapies are on the rise and are key therapies in the treatment of some of the most common cancer entities. Proarrhythmic effects have been described in patients treated with SERMs while little to none is known about the electrophysiological effects of the potentially less arrhythmogenic selective estrogen receptor degraders.

Methods: Twenty hearts of female New Zealand White rabbits were excised and retrogradely perfused employing a Langendorff setup.

Usefulness of the MADIT-ICD Benefit Score in a Large Mixed Patient Cohort of Primary Prevention of Sudden Cardiac Death.

Background: Decision-making in primary prevention is not always trivial and many clinical scenarios are not reflected in current guidelines. To help evaluate a patient’s individual risk, a new score to predict the benefit of an implantable defibrillator (ICD) for primary prevention, the MADIT-ICD benefit score, has recently been proposed. The score tries to predict occurrence of ventricular arrhythmias and non-arrhythmic death based on data from four previous MADIT trials.

Pulmonary Vein Isolation in Obese Compared to Non-Obese Patients: Real-Life Experience from a Large Tertiary Center.

1. Introduction: Pulmonary vein isolation (PVI) is an established procedure used to achieve rhythm control in atrial fibrillation (AF). In obese patients (pts), in whom AF occurs more frequently, a reduced effectiveness of PVI has been observed.

[Electromagnetic interference in 3D-mapping procedures].

Catheter-based ablation is nowadays a safe and widespread procedure for the treatment of cardiac arrhythmia. This requires exact anatomical knowledge both before and during the examination and is an important prerequisite for targeted treatment. At the beginning of the era of interventional catheter-based treatment, fluoroscopy was the only and usual means of visualization, whereas in the middle of the 1990s continuous 3D-mapping systems were developed for the non-fluoroscopic examination of patients.

[Anatomy of the left ventricle for endocardial ablation].

As with all cardiac interventions, performing left ventricular ablation requires profound knowledge of cardiac anatomy. The aim of this article is to provide an overview of left ventricular anatomy and to characterize complex and clinically relevant structures from an electrophysiologist-centered perspective. In addition to the different access routes, the trabecular network, the left ventricular outflow tract, and the left ventricular conduction system, complex anatomical structures such as the aortomitral continuity and the left ventricular summit are also explained.

Cardiovascular risk of energy drinks: Caffeine and taurine facilitate ventricular arrhythmias in a sensitive whole-heart model.

Background: Several case reports have suggested an increased risk of sudden cardiac death due to energy drinks. Therefore, the purpose of this study was to assess acute electrophysiologic effects of caffeine and taurine, two of the main ingredients of energy drinks, in an experimental whole-heart model.

Methods And Results: Twenty-five rabbit hearts were excised, retrogradely perfused, and assigned to two groups.

The Incidence, Electrophysiological Characteristics and Ablation Outcome of Left Atrial Tachycardias after Pulmonary Vein Isolation Using Three Different Ablation Technologies.

Background: Left atrial tachycardias (LAT) are a well-known outcome of pulmonary vein isolation (PVI). Few data are available on whether the catheter used to perform PVI influences the incidence, as well as the characteristics of post PVI LAT. We present data on LAT following PVI by the following three ablation technologies: (1) phased multi-electrode radiofrequency catheter (PVAC), (2) irrigated single-tip catheter (iRF), and (3) cryoballoon ablation.

Electrophysiologic effects of sacubitril in different arrhythmia models.

Background: Previous studies report conflicting data regarding anti- or proarrhythmic effects of sacubitril. Aim of this study was to assess the impact of acute sacubitril treatment in different arrhythmia models.

Methods: Sacubitril was administered (3, 5, 10 μM) in 12 isolated rabbit hearts.

Safe electrophysiologic profile of dexmedetomidine in different experimental arrhythmia models.

Previous studies suggest an impact of dexmedetomidine on cardiac electrophysiology. However, experimental data is sparse. Therefore, purpose of this study was to investigate the influence of dexmedetomidine on different experimental models of proarrhythmia.

Very Long-Term Follow-Up in Cardiac Resynchronization Therapy: Wider Paced QRS Equals Worse Prognosis.

Background: Different electrocardiogram (ECG) findings are known to be independent predictors of clinical response to cardiac resynchronization therapy (CRT). It remains unknown how these findings influence very long-term prognosis.

Methods And Results: A total of 102 consecutive patients (75 males, mean age 65 ± 10 years) referred to our center for CRT implantation had previously been included in this prospective observational study.

Cardiac Sympathetic Activity and Rhythm Control Following Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation-A Prospective I-mIBG-SPECT/CT Imaging Study.

Background: Pulmonary vein isolation (PVI) and antiarrhythmic drug therapy are established treatment strategies to preserve sinus rhythm in atrial fibrillation (AF). However, the efficacy of both interventional and pharmaceutical therapy is still limited. Solid evidence suggests an important role of the cardiac sympathetic nervous system in AF.

Experimental evidence for proarrhythmic effects of nonsteroidal anti-inflammatory drugs in a sensitive whole-heart model.

Background: Previous studies have raised serious concerns on cardiovascular safety of widely prescribed nonsteroidal anti-inflammatory drugs (NSAIDs). Therefore, the aim of this study was to characterize the electrophysiological effects of certain NSAIDs in an established whole heart model of proarrhythmia.

Methods And Results: Thirty-eight hearts of New Zealand White rabbits were harvested and retrogradely perfused employing a Langendorff setup, and electrophysiology studies were performed to investigate action potential duration at 90% of repolarization (APD ), QT intervals, and effective refractory period (ERP).

Quantifying Left Atrial Size in the Context of Atrial Fibrillation Ablation: Which Echocardiographic Method Correlates to Outcome of Pulmonary Venous Isolation?

Introduction: Multiple studies have shown that left atrial (LA) enlargement is a strong predictor of poor outcome after catheter ablation of atrial fibrillation (AF). LA size is commonly approximated as the diameter in the parasternal long axis. It remains unknown whether more precise echocardiographic measurements of LA size allow for better correlation with outcome after pulmonary vein isolation (PVI).

Prospective blinded evaluation of smartphone-based ECG for differentiation of supraventricular tachycardia from inappropriate sinus tachycardia.

Introduction: Supraventricular tachycardias (SVT) are often difficult to document due to their intermittent, short-lasting nature. Smartphone-based one-lead ECG monitors (sECG) were initially developed for the diagnosis of atrial fibrillation. No data have been published regarding their potential role in differentiating inappropiate sinus tachycardia (IST) from regular SVT.

Predictors of AVNRT Recurrence After Slow Pathway Modification.

Atrioventricular nodal reentry tachycardia (AVNRT) is the most common regular supraventricular tachycardia (SVT). Slow pathway modification (SPM) is the accepted first line treatment with reported success rates around 95%. Information regarding possible predictors of AVNRT recurrence is scarce.

Divergent Electrophysiological Effects of Loperamide and Naloxone in a Sensitive Whole-Heart Model.

Several case reports suggest QT prolongation leading to ventricular arrhythmias with fatal outcome after intoxication with the μ-opioid receptor agonist and anti-diarrheal agent loperamide. The number of cases of loperamide misuse are growing due to its potential stimulating effects. Loperamide intoxications can be treated by naloxone.

Antiarrhythmic Effect of Ranolazine in Combination with Selective NCX-Inhibition in an Experimental Model of Atrial Fibrillation.

The aim of this study was to investigate the effects of a combination of ranolazine with different selective inhibitors of the Na/Ca-exchanger (NCX) in an established experimental model of atrial fibrillation (AF). Eighteen hearts of New Zealand white rabbits were retrogradely perfused. Atrial catheters were used to record monophasic action potentials (aPRR).

Outcome of catheter ablation in the very elderly-insights from a large matched analysis.

Background: Ablation emerged as first line therapy in the treatment of various arrhythmias. Nevertheless, in older patients (pts), decision is often made pro drug treatment as more complications and less benefit are suspected.

Hypothesis: We hypothesized that different kind of ablations can be performed safely regardless of the pts age.

Concomitant Treatment with Proton Pump Inhibitors and Cephalosporins Does Not Enhance QT-Associated Proarrhythmia in Isolated Rabbit Hearts.

Recent results from data mining analyses and reports of adverse drug events suggest a QT-prolonging drug-drug interaction resulting from the combination of distinct proton pump inhibitors and cephalosporins. Therefore, this study aimed at investigating the effect of the suspected QT-prolonging combinations of lansoprazole + ceftriaxone and esomeprazole + cefazolin, respectively. 26 hearts of New Zealand White rabbits were retrogradely perfused and paced at different cycle lengths.