scholarly journals Computer models of endo-epicardial dissociation of electrical activity and transmural conduction during atrial fibrillation

2016 ◽  
Author(s):  
Ali Gharaviri
Keyword(s):  
Atrial Fibrillation ◽  
Electrical Activity ◽  
Computer Models

scholarly journals Electrocardiographic Imaging for Atrial Fibrillation: A Perspective From Computer Models and Animal Experiments to Clinical Value

2021 ◽  
Vol 12 ◽  
Author(s):  
João Salinet ◽  
Rubén Molero ◽  
Fernando S. Schlindwein ◽  
Joël Karel ◽  
Miguel Rodrigo ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Electrical Activity ◽  
Ventricular Arrhythmias ◽  
Animal Experiments ◽  
Computer Models ◽  
Clinical Results ◽  
Clinical Value ◽  
Electrocardiographic Imaging ◽  
Human Experiments

Electrocardiographic imaging (ECGI) is a technique to reconstruct non-invasively the electrical activity on the heart surface from body-surface potential recordings and geometric information of the torso and the heart. ECGI has shown scientific and clinical value when used to characterize and treat both atrial and ventricular arrhythmias. Regarding atrial fibrillation (AF), the characterization of the electrical propagation and the underlying substrate favoring AF is inherently more challenging than for ventricular arrhythmias, due to the progressive and heterogeneous nature of the disease and its manifestation, the small volume and wall thickness of the atria, and the relatively large role of microstructural abnormalities in AF. At the same time, ECGI has the advantage over other mapping technologies of allowing a global characterization of atrial electrical activity at every atrial beat and non-invasively. However, since ECGI is time-consuming and costly and the use of electrical mapping to guide AF ablation is still not fully established, the clinical value of ECGI for AF is still under assessment. Nonetheless, AF is known to be the manifestation of a complex interaction between electrical and structural abnormalities and therefore, true electro-anatomical-structural imaging may elucidate important key factors of AF development, progression, and treatment. Therefore, it is paramount to identify which clinical questions could be successfully addressed by ECGI when it comes to AF characterization and treatment, and which questions may be beyond its technical limitations. In this manuscript we review the questions that researchers have tried to address on the use of ECGI for AF characterization and treatment guidance (for example, localization of AF triggers and sustaining mechanisms), and we discuss the technological requirements and validation. We address experimental and clinical results, limitations, and future challenges for fruitful application of ECGI for AF understanding and management. We pay attention to existing techniques and clinical application, to computer models and (animal or human) experiments, to challenges of methodological and clinical validation. The overall objective of the study is to provide a consensus on valuable directions that ECGI research may take to provide future improvements in AF characterization and treatment guidance.

scholarly journals Heart Failure Differentially Modulates Natural (Sinoatrial Node) and Ectopic (Pulmonary Veins) Pacemakers: Mechanism and Therapeutic Implication for Atrial Fibrillation

2019 ◽  
Vol 20 (13) ◽  
pp. 3224 ◽  
Author(s):  
Chao-Shun Chan ◽  
Yung-Kuo Lin ◽  
Yao-Chang Chen ◽  
Yen-Yu Lu ◽  
Shih-Ann Chen ◽  
...  
Keyword(s):  
Heart Failure ◽  
Atrial Fibrillation ◽  
Electrical Activity ◽  
Sinoatrial Node ◽  
Sick Sinus Syndrome ◽  
Pulmonary Veins ◽  
Calcium Handling ◽  
Adrenergic Stimulation ◽  
Therapeutic Implications ◽  
Cardiac Filling

Heart failure (HF) frequently coexists with atrial fibrillation (AF) and dysfunction of the sinoatrial node (SAN), the natural pacemaker. HF is associated with chronic adrenergic stimulation, neurohormonal activation, abnormal intracellular calcium handling, elevated cardiac filling pressure and atrial stretch, and fibrosis. Pulmonary veins (PVs), which are the points of onset of ectopic electrical activity, are the most crucial AF triggers. A crosstalk between the SAN and PVs determines PV arrhythmogenesis. HF has different effects on SAN and PV electrophysiological characteristics, which critically modulate the development of AF and sick sinus syndrome. This review provides updates to improve our current understanding of the effects of HF in the electrical activity of the SAN and PVs as well as therapeutic implications for AF.

METHODS TO QUANTITATE ATRIAL ELECTRICAL ACTIVITY USING ELECTROGRAMS ACQUIRED DURING ATRIAL FIBRILLATION

2014 ◽  
Vol 26 (06) ◽  
pp. 1430001
Author(s):  
Edward J. Ciaccio ◽  
Angelo B. Biviano ◽  
Hasan Garan
Keyword(s):  
Atrial Fibrillation ◽  
Electrical Activity ◽  
Frequency Domain ◽  
Time Domain ◽  
Periodic Pattern ◽  
Spectral Parameters ◽  
Domain Method ◽  
Frequency Domain Methods ◽  
Atrial Electrograms ◽  
Fractionated Electrograms

Herein, commonly used quantitative bioengineering methods that have been developed to analyze fractionated electrograms recorded from the surface of the atria during atrial fibrillation (AF) are described. Techniques were categorized as time-domain and frequency-domain methods. The main time-domain method is peak counting. Its variations based on preprocessing and thresholding are discussed. The main frequency-domain method is spectral analysis. Two spectral estimators, the discrete Fourier transform (DFT) and the new spectral estimator (NSE) are described. The ability of each estimator to detect the main periodic component of fractionated atrial electrograms is compared. Several spectral parameters that are used for analysis of atrial electrograms including the dominant frequency (DF), dominant amplitude (DA) and mean spectral profile (MP) are defined. Mean values of these parameters are compared in paroxysmal versus persistent AF fractionated electrograms based upon the results of several studies. Time-domain methods are shown to work best for analysis with deterministic, not fractionated atrial electrograms. For fractionated atrial electrograms, frequency-domain methods are often used. The DF, DA and MP spectral parameters are significantly different in paroxysmal versus longstanding persistent AF recordings. The DF and the DA are significantly higher, and the MP is significantly lower, in persistent AF electrogram recordings. The higher DF and DA parameter values reflect substrate remodeling in persistent AF, which increases the stability of the electrical activation pattern. The lower MP value in persistent AF reflects the lower spectral noise floor, indicative of a less complex and more periodic pattern of electrical activity.

scholarly journals Genome-wide association meta-analysis of PR interval identifies 47 novel loci associated with atrial and atrioventricular electrical activity

2018 ◽  
Author(s):  
Jessica van Setten ◽  
Jennifer A. Brody ◽  
Yalda Jamshidi ◽  
Brenton R. Swenson ◽  
Anne M. Butler ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Electrical Activity ◽  
Genome Wide Association Study ◽  
Meta Analysis ◽  
Genome Wide Association ◽  
Regulatory Regions ◽  
European Descent ◽  
Genome Wide ◽  
A Genome ◽  
Pr Interval

ABSTRACTElectrocardiographic PR interval measures atrial and atrioventricular depolarization and conduction, and abnormal PR interval is a risk factor for atrial fibrillation and heart block. We performed a genome-wide association study in over 92,000 individuals of European descent and identified 44 loci associated with PR interval (34 novel). Examination of the 44 loci revealed known and novel biological processes involved in cardiac atrial electrical activity, and genes in these loci were highly over-represented in several cardiac disease processes. Nearly half of the 61 independent index variants in the 44 loci were associated with atrial or blood transcript expression levels, or were in high linkage disequilibrium with one or more missense variants. Cardiac regulatory regions of the genome as measured by cardiac DNA hypersensitivity sites were enriched for variants associated with PR interval, compared to non-cardiac regulatory regions. Joint analyses combining PR interval with heart rate, QRS interval, and atrial fibrillation identified additional new pleiotropic loci. The majority of associations discovered in European-descent populations were also present in African-American populations. Meta-analysis examining over 105,000 individuals of African and European descent identified additional novel PR loci. These additional analyses identified another 13 novel loci. Together, these findings underscore the power of GWAS to extend knowledge of the molecular underpinnings of clinical processes.

Pulmonary Vein Internal Electrical Activity Does Not Contribute to the Maintenance of Atrial Fibrillation

2003 ◽  
Vol 26 (6) ◽  
pp. 1356-1362 ◽  
Author(s):  
GJIN NDREPEPA ◽  
MICHAEL A.E. SCHNEIDER ◽  
MARTIN R. KARCH ◽  
STEFAN WEBER ◽  
JÜRGEN SCHREIECK ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Electrical Activity ◽  
Pulmonary Vein
Sign in / Sign up

Export Citation Format

Share Document