RIPPLE-VT study: Multicenter prospective evaluation of ventricular tachycardia substrate ablation by targeting scar channels to eliminate latest scar potentials without direct ablation.

Background: Recurrent ventricular tachycardia (VT) can be treated by substrate modification of the myocardial scar by catheter ablation during sinus rhythm without VT induction. Better defining this arrhythmic substrate could help improve outcome and reduce ablation burden.

Objective: The study aimed to limit ablation within postinfarction scar to conduction channels within the scar to reduce VT recurrence.

Quantitative assessment of myocardial fibrosis by digital image analysis: An adjunctive tool for pathologist "ground truth".

Aims: Myocardial fibrosis (MF) is a common pathological process in a wide range of cardiovascular diseases. Its quantity has diagnostic and prognostic relevance. We aimed to assess if the complementary use of an automated artificial intelligence software might improve the precision of the pathologist´s quantification of MF on endomyocardial biopsies (EMB).

Multielectrode mapping for premature ventricular contraction ablation - A prospective, multicenter study.

Purpose: We aim to evaluate whether the use of a multielectrode mapping catheter could lead to higher efficacy of premature ventricular contraction (PVC) ablation.

Methods: Prospective, multicenter nonrandomized study of consecutive patients referred for PVC ablation from January 2018 to June 2021. Patients were separated into two groups: activation map performed with the PentaRay catheter (Study group) or with the ablation catheter (Control group).

SparkleMap-based left atrial flutter mapping and ablation.

Ablation of atypical left atrial flutters (LAF) is very challenging due to the complexity of the underlying atrial substrate and diverse arrhythmia mechanisms. The interpretation of the arrhythmia mechanism is usually difficult, even using advanced three-dimensional (3D) mapping systems. SparkleMap is a novel mapping algorithm that displays each electrogram as a green dot that lights up at the point corresponding to the local activation time, superimposed either on the substrate or the local activation time 3D-maps.

Automatic identification of areas with low-voltage fragmented electrograms for the detection of the critical isthmus of atypical atrial flutters.

Introduction: Critical isthmuses of atypical atrial flutters (AAFLs) are usually located at slow conduction areas that exhibit fractionated electrograms. We tested a novel software, intended for integration with a commercially available navigation system, that automatically detects fractionated electrograms, to identify the critical isthmus in patients with AAFL ablation.

Methods And Results: All available patients were analyzed; 27 patients with 33 AAFLs were included.

Impact of different activation wavefronts on ischemic myocardial scar electrophysiological properties during high-density ventricular tachycardia mapping and ablation.

Introduction: Scar-related ventricular tachycardia (VT) usually results from an underlying reentrant circuit facilitated by anatomical and functional barriers. The later are sensitive to the direction of ventricular activation wavefronts. We aim to evaluate the impact of different ventricular activation wavefronts on the functional electrophysiological properties of myocardial tissue.

Outcome of ventricular tachycardia catheter ablation in ischemic heart disease patients using a high-density mapping substrate-based approach: A prospective cohort study.

Introduction And Objective: Radiofrequency catheter ablation (RCA) for ventricular tachycardia (VT) in patients with ischemic heart disease (IHD) is associated with a reduced risk of VT storm and implantable cardioverter defibrillator (ICD) shocks. We aim to report the outcome after a single RCA procedure for VT in patients with IHD using a high-density substrate-based approach.

Methods: We conducted a prospective, observational, single-center and single-arm study involving patients with IHD, referred for RCA procedure for VT using high-density mapping catheters.

Novel "late potential map" algorithm: Abnormal potentials and scar channels detection for ventricular tachycardia ablation.

Background: Automated systems for substrate mapping in the context of ventricular tachycardia (VT) ablation may annotate far-field rather than near-field signals, rendering the resulting maps hard to interpret. Additionally, quantitative assessment of local conduction velocity (LCV) remains an unmet need in clinical practice. We evaluate whether a new late potential map (LPM) algorithm can provide an automatic and reliable annotation and localized bipolar voltage measurement of ventricular electrograms (EGMs) and if LCV analysis allows recognizing intrascar conduction corridors acting as VT isthmuses.

Anticoagulation after typical atrial flutter ablation: Systematic review and meta-analysis.

Background: Cavotricuspid isthmus (CTI) ablation in typical atrial flutter (AFL) restores sinus rhythm in 95% of patients, which may lead to the discontinuation of oral anticoagulation during follow-up. Therefore, we aimed to systematically review the clinical impact of oral anticoagulation in the incidence of thromboembolic events (TE) after typical AFL ablation.

Methods: We searched for controlled studies evaluating the impact of anticoagulation in the incidence of TE in patients submitted to AFL ablation in MEDLINE, CENTRAL, PsycINFO database (June/2021).

Optimizing prognosis in atrial fibrillation: A call to action in Portugal.

Atrial fibrillation (AF), the most common arrhythmia in the adult population worldwide, represents a significant burden in terms of cardiovascular mortality and morbidity and has repercussions on health economics. Oral anticoagulation (OAC) is key to stroke prevention in AF and, in recent years, results from landmark clinical trials of non-vitamin K oral anticoagulants (NOAC) have triggered a paradigm shift in thrombocardiology. Despite these advances, there is still a significant residual vascular risk associated with silent AF, bleeding, premature sudden death and heart failure.

Portuguese National Registry on Cardiac Electrophysiology, 2017 and 2018.

Introduction: The authors present the results of the national cardiac electrophysiology registry of the Portuguese Association of Arrhythmology, Pacing and Electrophysiology (APAPE) and the Portuguese Institute of Cardiac Rhythm (IPRC) for 2017 and 2018.

Methods: The registry is annual, voluntary, and observational. Data are collected retrospectively.

A Primary Prevention Clinical Risk Score Model for Patients With Brugada Syndrome (BRUGADA-RISK).

Objectives: The goal of this study was to develop a risk score model for patients with Brugada syndrome (BrS).

Background: Risk stratification in BrS is a significant challenge due to the low event rates and conflicting evidence.

Methods: A multicenter international cohort of patients with BrS and no previous cardiac arrest was used to evaluate the role of 16 proposed clinical or electrocardiogram (ECG) markers in predicting ventricular arrhythmias (VAs)/sudden cardiac death (SCD) during follow-up.

Electroanatomic Characterization and Ablation of Scar-Related Isthmus Sites Supporting Perimitral Flutter.

Objectives: The authors reviewed 3-dimensional electroanatomic maps of perimitral flutter to identify scar-related isthmuses and determine their effectiveness as ablation sites.

Background: Perimitral flutter is usually treated by linear ablation between the left lower pulmonary vein and mitral annulus. Conduction block can be difficult to achieve, and recurrences are common.

Radiofrequency catheter ablation of ventricular tachycardia in ischemic heart disease in light of current practice: a systematic review and meta-analysis of randomized controlled trials.

Purpose: Ventricular tachycardia (VT) is a frequent cause of mortality and morbidity in patients with ischemic heart disease (IHD). We aim to perform a systematic review and meta-analysis of randomized controlled trials (RCT) of radiofrequency catheter ablation (RCA) of VT in patients with IHD and to discuss its appropriate timing and limitations.

Methods: Literature searches of MEDLINE, CENTRAL, the Cochrane Database of Systematic Reviews, Health Technology Assessment, and PsycINFO were performed in February 2020.

The sensitivity of DPD scintigraphy to detect transthyretin cardiac amyloidosis in V30M mutation depends on the phenotypic expression of the disease.

There is a growing need for a non-invasive test to detect cardiac involvement in patients with transthyretin-related hereditary amyloidosis (ATTR) caused by V30M mutation. Tc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy is a promising method, but its accuracy in this particular mutation remains unknown. A cohort of 179 patients: 92 with early-onset disease (EoD, symptoms <50-years-old), 33 with late-onset disease (LoD) and 54 asymptomatic carriers were prospectively evaluated and underwent DPD scintigraphy, which was compared with the results of echocardiogram, ambulatory blood pressure monitoring, 24 h-Holter, myocardial I-metaiodobenzylguanidine imaging and NT-proBNP.

Ripple-AT Study: A Multicenter and Randomized Study Comparing 3D Mapping Techniques During Atrial Tachycardia Ablations.

Background: Ripple mapping (RM) is an alternative approach to activation mapping of atrial tachycardia (AT) that avoids electrogram annotation. We tested whether RM is superior to conventional annotation based local activation time (LAT) mapping for AT diagnosis in a randomized and multicenter study.

Methods: Patients with AT were randomized to either RM or LAT mapping using the CARTO3v4 CONFIDENSE system.

Identification of a critical isthmus in complex macroreentrant atrial tachycardia using Ripple mapping in a patient with surgically repaired Ebstein's anomaly.

Ripple mapping is a novel, three-dimensional, electroanatomic mapping tool that displays each electrogram at its corresponding 3-dimensional coordinate as a dynamic moving bar, which changes in length according to the electrogram voltage-time relationship. We present the case of a 43-year-old male patient with surgically repaired Ebstein's anomaly who previously underwent two unsuccessful ablation procedures for right atrial flutter (cavotricuspid isthmus and intercaval lines). Ripple mapping was decisive, enabling the arrhythmia mechanism to be appropriately recognized, and a distinction to be made between critical areas of the circuit and delayed activated bystander regions.

circRNA-miRNA cross-talk in the transition from paroxysmal to permanent atrial fibrillation.

Background: Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in western countries. The factors governing the progression of AF to a permanent chronic condition are still not well characterized. Among epigenetic factors, non-coding RNAs (ncRNAs) such as miRNAs and lncRNAs have been recently described as important players involved in the AF progression.