Electrographic flow mapping of persistent atrial fibrillation: intra- and inter-procedure reproducibility in the absence of 'ground truth'.

Aims: Validating mapping systems that identify atrial fibrillation (AF) sources (focal/rotational activity) is confounded by the absence of ground truth. A key concern of prior mapping technologies is spatiotemporal instability, manifesting as poor map reproducibility. Electrographic flow (EGF) employs a novel algorithm that visualizes atrial electrical wavefront propagation to identify putative AF sources.

Visualization of electrographic flow fields of increasing complexity and detection of simulated sources during spontaneously persistent AF in an animal model.

Background: Mapping algorithms have thus far been unable to localize triggers that serve as drivers of AF, but electrographic flow (EGF) mapping provides an innovative method of estimating and visualizing , near real-time cardiac wavefront propagation.

Materials And Methods: One-minute unipolar EGMs were recorded in the right atrium (RA) from a 64-electrode basket catheter to generate EGF maps during atrial rhythms of increasing complexity. They were obtained from 3 normal, animals in sinus rhythm (SR) and from 6 animals in which persistent AF which was induced by rapid atrial pacing.

Left atrial anatomical variations correlate with atrial fibrillation sources near the left atrial ridge.

Introduction: Anatomical variations and characteristics of the left atrium (LA) may have a previously undescribed effect on source locations in atrial fibrillation (AF). This is the first study aiming to investigate the relationship between anatomical characteristics of the LA and non-PV sources detected by electrographic flow (EGF) mapping in patients with persistent AF.

Materials And Methods: We analyzed cardiac computed tomography (CT) and EGF mapping data in patients who underwent radiofrequency catheter ablation (CA).

Electrographic flow mapping for atrial fibrillation: theoretical basis and preliminary observations.

Ablation strategies remain poorly defined for persistent atrial fibrillation (AF) patients with recurrence despite intact pulmonary vein isolation (PVI). As the ability to perform durable PVI improves, the need for advanced mapping to identify extra-PV sources of AF becomes increasingly evident. Multiple mapping technologies attempt to localize these self-sustained triggers and/or drivers responsible for initiating and/or maintaining AF; however, current approaches suffer from technical limitations.

Functional electrographic flow patterns in patients with persistent atrial fibrillation predict outcome of catheter ablation.

Aims: Electrographic flow (EGF) mapping is a method to detect action potential sources within the atria. In a double-blinded retrospective study we evaluated whether sources detected by EGF are related to procedural outcome.

Methods: EGF maps were retrospectively generated using the Ablamap® software from unipolar data recorded with a 64-pole basket catheter from patients who previously underwent focal impulse and rotor modulation-guided ablation.

Velocity characteristics of atrial fibrillation sources determined by electrographic flow mapping before and after catheter ablation.

Background: Electrographic-Flow-(EGF)-Mapping is a novel method to identify Atrial Fibrillation (AF) drivers. Sources of excitation during AF can be characterized and monitored.

Objective: The aim of this study was to evaluate the correlation between velocity of EGF around a respective AF source and its spatial variability (SV) and stability (SST).

Identification of active atrial fibrillation sources and their discrimination from passive rotors using electrographical flow mapping.

Background: The optimal ablation approach for the treatment of persistent atrial fibrillation (AF) is still under debate; however, the identification and elimination of AF sources is thought to play a key role. Currently available technologies for the identification of AF sources are not able to differentiate between active rotors or focal impulse (FI) and passive circular turbulences as generated by the interaction of a wave front with a functional obstacle such as fibrotic tissue.

Objectives: This study introduces electrographic flow (EGF) mapping as a novel technology for the identification and characterization of AF sources in humans.

Adhesion forces measured at the level of a terminal plate of the fly's seta.

The attachment pads of fly legs are covered with setae, each ending in small terminal plates coated with secretory fluid. A cluster of these terminal plates contacting a substrate surface generates strong attractive forces that hold the insect on smooth surfaces. Previous research assumed that cohesive forces and molecular adhesion were involved in the fly attachment mechanism.

Interaction of PSD-95 with potassium channels visualized by fluorescence lifetime-based resonance energy transfer imaging.

Resonance energy transfer (RET) has been extensively used to estimate the distance between two different fluorophores. This study demonstrates how protein-protein interactions can be visualized and quantified in living cells by time-correlated single-photon counting (TCSPC) imaging techniques that exploit the RET between appropriate fluorescent labels. We used this method to investigate the association of the potassium inward rectifier channel Kir2.