Effective ablation settings that predict chronic scar after atrial ablation with HELIOSTAR™ multi-electrode radiofrequency balloon catheter.

Background: Radiofrequency balloon (RFB) ablation (HELIOSTAR™, Biosense Webster) has been developed to improve pulmonary vein ablation efficiency over traditional point-by-point RF ablation approaches. We aimed to find effective parameters for RFB ablation that result in chronic scar verified by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR).

Methods: A chronic canine model (n = 8) was used to ablate in the superior vena cava (SVC), the right superior and the left inferior pulmonary vein (RSPV and LIPV), and the left atrial appendage (LAA) with a circumferential ablation approach (RF energy was delivered to all electrodes simultaneously) for 20 s or 60 s.

Performance of off-the-shelf machine learning architectures and biases in low left ventricular ejection fraction detection.

Background: Artificial intelligence-machine learning (AI-ML) has demonstrated the ability to extract clinically useful information from electrocardiograms (ECGs) not available using traditional interpretation methods. There exists an extensive body of AI-ML research in fields outside of cardiology including several open-source AI-ML architectures that can be translated to new problems in an "off-the-shelf" manner.

Objective: We sought to address the limited investigation of which if any of these off-the-shelf architectures could be useful in ECG analysis as well as how and when these AI-ML approaches fail.

Left atrial functional changes associated with repeated catheter ablations for atrial fibrillation.

Introduction: The impact of repeated atrial fibrillation (AF) ablations on left atrial (LA) mechanical function remains uncertain, with limited long-term follow-up data.

Methods: This retrospective study involved 108 AF patients who underwent two catheter ablations with cardiac magnetic resonance imaging (MRI) done before and 3 months after each of the ablations from 2010 to 2021. The rate of change in peak longitudinal atrial strain (PLAS) assessed LA function.

Analytical microscopy techniques using coaxial and oblique illuminations to detect thin glass particulates generated from glass vials for parenteral drug products.

Glass vials are the most widely used primary containers for the packaging of parenteral products due to their optical clarity, general inertness, and hermetic properties, but under certain circumstances, they can pose safety concerns. Most of these issues are related to the potential formation of glass particulates through delamination or precipitation, resulting from the chemical interaction between the drug product and the inner surface of the glass vial. Hence, it is imperative for pharmaceutical companies to conduct product-vial compatibility studies to determine the appropriate packaging/container closure system.

Real-Time Ambulatory ECG Does Not Expedite Care.

Background: Ambulatory ECG (AECG) monitoring is pivotal to the diagnosis of arrhythmias and can be performed with near "real-time" notification of abnormalities. There are limited data on the relative benefit of real-time monitoring compared with traditional Holter monitoring.

Methods And Results: This is a retrospective observational analysis of University of Utah Health patients who underwent ambulatory ECG studies from 2010 to 2022.

Dementia risk reduction between DOACs and VKAs in AF: A systematic review and meta-analysis.

Introduction: Direct oral anticoagulants (DOACs) become the recommended treatment over vitamin K antagonists (VKA) in patients with non-valvular atrial fibrillation (AF). However, their effectiveness in reducing cognitive impairment and dementia compared to VKA remains unclear.

Methods: A systematic literature search was conducted on Ovid MEDLINE, EMBASE, and Cochrane Database.

Discordant Treatment Goals for Patients With Atrial Fibrillation and Clinical Trials Metrics.

Background: Most clinical trials define successful atrial fibrillation (AF) treatment as no AF episodes longer than 30 seconds. Yet, there has been minimal study of how patients define successful treatment and whether their perspectives align with trial outcomes.

Objectives: Survey patients with AF to identify: 1) what aspect of AF is most important to address (frequency, duration, or severity of AF episodes); 2) what AF burden would be considered acceptable to consider treatment successful; and 3) to establish patient preferences for successful treatment thresholds for a validated patient-reported outcome (PRO) score.

Comprehensive analysis of same day discharge after atrial fibrillation ablation: Clinical, cost, and patient reported outcomes.

Background: Same day discharge (SDD) following atrial fibrillation (AF) ablation procedure has emerged as routine practice, and primarily driven by operator discretion. However, the impacts of SDD on clinical outcomes, healthcare system costs, and patient reported outcomes (PROs) have not been systematically studied.

Methods: We retrospectively analyzed patients undergoing routine AF ablation procedures with SDD versus overnight observation (NSDD).

Prognostic Impact of Sinus Rhythm in Atrial Fibrillation Patients: Separating Rhythm Outcomes From Randomized Strategy Findings From the CABANA Trial.

Background: Clinically detected atrial fibrillation (AF) is associated with a significant increase in mortality and other adverse cardiovascular events. Since the advent of effective methods for AF rhythm control, investigators have attempted to determine how much these adverse prognostic AF effects could be mitigated by the restoration of sinus rhythm (SR) and whether the method used mattered.

Methods: The CABANA trial (Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) randomized 2204 AF patients to ablation versus drug therapy, of which 1240 patients were monitored in follow-up using the CABANA ECG rhythm monitoring system.

Ablation-induced left atrial mechanical dysfunction recovers in weeks after ablation.

Background: The immediate impact of catheter ablation on left atrial mechanical function and the timeline for its recovery in patients undergoing ablation for atrial fibrillation (AF) remain uncertain. The mechanical function response to catheter ablation in patients with different AF types is poorly understood.

Methods: A total of 113 AF patients were included in this retrospective study.

Leadless pacemaker tine damage and fracture: novel complications of a novel device fixation mechanism.

Background: Leadless pacemakers represent a paradigm-changing advancement. However, they required innovative and novel device design, including the use of nitinol tines for fixation.

Objective: We aimed to understand the potential for fracture in the novel tine-based fixation mechanism.

Mortality benefit with AF ablation: Impact of normal sinus rhythm seen in CABANA and EAST AFnet.

Atrial fibrillation (AF) is significantly associated with morbidity and mortality and erodes the quality and quantity of life. It is standard of care to treat patients with AF and an increased risk of stroke with oral anticoagulation therapy, but the more daunting question many clinicians face is whether to pursue a "rate-only" or "rhythm" control strategy. Historical studies over the years have sought to answer this question but have found no significant difference in major clinical outcomes between the two strategies.

Cardiac myosin-binding protein C N-terminal interactions with myosin and actin filaments: Opposite effects of phosphorylation and M-domain mutations.

N-terminal cardiac myosin-binding protein C (cMyBP-C) domains (C0-C2) bind to thick (myosin) and thin (actin) filaments to coordinate contraction and relaxation of the heart. These interactions are regulated by phosphorylation of the M-domain situated between domains C1 and C2. In cardiomyopathies and heart failure, phosphorylation of cMyBP-C is significantly altered.

Drug discovery for heart failure targeting myosin-binding protein C.

Cardiac MyBP-C (cMyBP-C) interacts with actin and myosin to fine-tune cardiac muscle contractility. Phosphorylation of cMyBP-C, which reduces the binding of cMyBP-C to actin and myosin, is often decreased in patients with heart failure (HF) and is cardioprotective in model systems of HF. Therefore, cMyBP-C is a potential target for HF drugs that mimic its phosphorylation and/or perturb its interactions with actin or myosin.