Minimal configuration of body surface potential mapping for discrimination of left versus right dominant frequencies during atrial fibrillation

[EN] Background: Ablation of drivers maintaining atrial fibrillation (AF) has been demonstrated as an effective therapy. Drivers in the form of rapidly activated atrial regions can be noninvasively localized to either left or right atria (LA, RA) with body surface potential mapping (BSPM) systems. This study quantifies the accuracy of dominant frequency (DF) measurements from reduced-leads BSPM systems and assesses the minimal configuration required for ablation guidance. Methods: Nine uniformly distributed lead sets of eight to 66 electrodes were evaluated. BSPM signals were registered simultaneously with intracardiac electrocardiograms (EGMs) in 16 AF patients. DF activity was analyzed on the surface potentials for the nine leads configurations, and the noninvasive measures were compared with the EGM recordings. Results: Surface DF measurements presented similar values than panoramic invasive EGM recordings, showing the highest DF regions in corresponding locations. The noninvasive DFs measures had a high correlation with the invasive discrete recordings; they presented a deviation of 0.8 for leads configurations with 12 or more electrodes. Conclusions: Reduced-leads BSPM systems enable noninvasive discrimination between LA versus RA DFs with similar results as higher-resolution 66-leads system. Our findings demonstrate the possible incorporation of simplified BSPM systems into clinical planning procedures for AF ablation.This work was supported in part by Generalitat-Valenciana Grants [ACIF/2013/021]; Instituto de SaludCarlos III, Ministerio de Ciencia e Innovacion [PI13/00903, PI13-01882, PI14/00857, PI16/01123, TEC2013-46067-R, DTS16/0160 and IJCI-2014-22178] cofound by FEDER.; Spanish Society of Cardiology [Clinical research Grants 2015]; Ministerio de Ciencia e Innovacion [Red RICRD12.0042.0001]; and the National Heart, Lung, and Blood Institute [P01-HL039707, P01-HL087226 and R01-HL118304].Rodrigo Bort, M.; Climent Martínez, BA.; Liberos Mascarell, A.; Fernández-Avilés, F.; Atienza, F.; Guillem Sánchez, MS.; Berenfeld, O. (2017). Minimal configuration of body surface potential mapping for discrimination of left versus right dominant frequencies during atrial fibrillation. Pacing and Clinical Electrophysiology. 40(8):940-946. https://doi.org/10.1111/pace.13133S940946408Atienza, F., Almendral, J., Ormaetxe, J. M., Moya, Á., Martínez-Alday, J. D., Hernández-Madrid, A., … Jalife, J. (2014). Comparison of Radiofrequency Catheter Ablation of Drivers and Circumferential Pulmonary Vein Isolation in Atrial Fibrillation. Journal of the American College of Cardiology, 64(23), 2455-2467. doi:10.1016/j.jacc.2014.09.053Narayan, S. M., Krummen, D. E., Clopton, P., Shivkumar, K., & Miller, J. M. (2013). Direct or Coincidental Elimination of Stable Rotors or Focal Sources May Explain Successful Atrial Fibrillation Ablation. Journal of the American College of Cardiology, 62(2), 138-147. doi:10.1016/j.jacc.2013.03.021Haissaguerre, M., Hocini, M., Denis, A., Shah, A. J., Komatsu, Y., Yamashita, S., … Dubois, R. (2014). Driver Domains in Persistent Atrial Fibrillation. Circulation, 130(7), 530-538. doi:10.1161/circulationaha.113.005421Atienza, F., Almendral, J., Jalife, J., Zlochiver, S., Ploutz-Snyder, R., Torrecilla, E. G., … Berenfeld, O. (2009). Real-time dominant frequency mapping and ablation of dominant frequency sites in atrial fibrillation with left-to-right frequency gradients predicts long-term maintenance of sinus rhythm. Heart Rhythm, 6(1), 33-40. doi:10.1016/j.hrthm.2008.10.024Lim, H. S., Zellerhoff, S., Derval, N., Denis, A., Yamashita, S., Berte, B., … Haissaguerre, M. (2015). Noninvasive Mapping to Guide Atrial Fibrillation Ablation. Cardiac Electrophysiology Clinics, 7(1), 89-98. doi:10.1016/j.ccep.2014.11.004Rodrigo, M., Guillem, M. S., Climent, A. M., Pedrón-Torrecilla, J., Liberos, A., Millet, J., … Berenfeld, O. (2014). Body surface localization of left and right atrial high-frequency rotors in atrial fibrillation patients: A clinical-computational study. Heart Rhythm, 11(9), 1584-1591. doi:10.1016/j.hrthm.2014.05.013Guillem, M. S., Climent, A. M., Millet, J., Arenal, Á., Fernández-Avilés, F., Jalife, J., … Berenfeld, O. (2013). Noninvasive Localization of Maximal Frequency Sites of Atrial Fibrillation by Body Surface Potential Mapping. Circulation: Arrhythmia and Electrophysiology, 6(2), 294-301. doi:10.1161/circep.112.000167Lux, R. L., Smith, C. R., Wyatt, R. F., & Abildskov, J. A. (1978). Limited Lead Selection for Estimation of Body Surface Potential Maps in Electrocardiography. IEEE Transactions on Biomedical Engineering, BME-25(3), 270-276. doi:10.1109/tbme.1978.326332Finlay, D. D., Nugent, C. D., Donnelly, M. P., & Black, N. D. (2008). Selection of optimal recording sites for limited lead body surface potential mapping in myocardial infarction and left ventricular hypertrophy. Journal of Electrocardiology, 41(3), 264-271. doi:10.1016/j.jelectrocard.2008.02.009Guillem, M. S., Castells, F., Climent, A. M., Bodí, V., Chorro, F. J., & Millet, J. (2008). Evaluation of lead selection methods for optimal reconstruction of body surface potentials. Journal of Electrocardiology, 41(1), 26-34. doi:10.1016/j.jelectrocard.2007.07.001De la Salud Guillem, M., Bollmann, A., Climent, A. M., Husser, D., Millet-Roig, J., & Castells, F. (2009). How Many Leads Are Necessary for a Reliable Reconstruction of Surface Potentials During Atrial Fibrillation? IEEE Transactions on Information Technology in Biomedicine, 13(3), 330-340. doi:10.1109/titb.2008.2011894Castells, F., Mora, C., Rieta, J. J., Moratal-Pérez, D., & Millet, J. (2005). Estimation of atrial fibrillatory wave from single-lead atrial fibrillation electrocardiograms using principal component analysis concepts. Medical & Biological Engineering & Computing, 43(5), 557-560. doi:10.1007/bf02351028Narayan, S. M., & Jalife, J. (2014). CrossTalk proposal: Rotors have been demonstrated to drive human atrial fibrillation. The Journal of Physiology, 592(15), 3163-3166. doi:10.1113/jphysiol.2014.271031Allessie, M., & de Groot, N. (2014). CrossTalk opposing view: Rotors have not been demonstrated to be the drivers of atrial fibrillation. The Journal of Physiology, 592(15), 3167-3170. doi:10.1113/jphysiol.2014.271809Berenfeld, O., & Oral, H. (2012). The quest for rotors in atrial fibrillation: Different nets catch different fishes. Heart Rhythm, 9(9), 1440-1441. doi:10.1016/j.hrthm.2012.04.029PEDRÓN-TORRECILLA, J., RODRIGO, M., CLIMENT, A. M., LIBEROS, A., PÉREZ-DAVID, E., BERMEJO, J., … GUILLEM, M. S. (2016). Noninvasive Estimation of Epicardial Dominant High-Frequency Regions During Atrial Fibrillation. Journal of Cardiovascular Electrophysiology, 27(4), 435-442. doi:10.1111/jce.12931Uijen, G., van Oosterom, A., & Hoekema, R. (1999). The Number of Independent Signals in Body Surface Maps. Methods of Information in Medicine, 38(02), 119-124. doi:10.1055/s-0038-1634176Ihara, Z., van Oosterom, A., Jacquemet, V., & Hoekema, R. (2007). Adaptation of the standard 12-lead electrocardiogram system dedicated to the analysis of atrial fibrillation. Journal of Electrocardiology, 40(1), 68.e1-68.e8. doi:10.1016/j.jelectrocard.2006.04.006Gerstenfeld, E. P., SippensGroenewegen, A., Lux, R. L., & Lesh, M. D. (2000). Derivation of an optimal lead set for measuring ectopic atrial activation from the pulmonary veins by using body surface mapping. Journal of Electrocardiology, 33, 179-185. doi:10.1054/jelc.2000.20307SippensGroenewegen, A., Peeters, H. A. P., Jessurun, E. R., Linnenbank, A. C., Robles de Medina, E. O., Lesh, M. D., & van Hemel, N. M. (1998). Body Surface Mapping During Pacing at Multiple Sites in the Human Atrium. Circulation, 97(4), 369-380. doi:10.1161/01.cir.97.4.369SALINET, J. L., TUAN, J. H., SANDILANDS, A. J., STAFFORD, P. J., SCHLINDWEIN, F. S., & NG, G. A. (2013). Distinctive Patterns of Dominant Frequency Trajectory Behavior in Drug-Refractory Persistent Atrial Fibrillation: Preliminary Characterization of Spatiotemporal Instability. Journal of Cardiovascular Electrophysiology, 25(4), 371-379. doi:10.1111/jce.12331Sanders, P., Berenfeld, O., Hocini, M., Jaïs, P., Vaidyanathan, R., Hsu, L.-F., … Haïssaguerre, M. (2005). Spectral Analysis Identifies Sites of High-Frequency Activity Maintaining Atrial Fibrillation in Humans. Circulation, 112(6), 789-797. doi:10.1161/circulationaha.104.517011Atienza, F., Almendral, J., Moreno, J., Vaidyanathan, R., Talkachou, A., Kalifa, J., … Berenfeld, O. (2006). Activation of Inward Rectifier Potassium Channels Accelerates Atrial Fibrillation in Humans. Circulation, 114(23), 2434-2442. doi:10.1161/circulationaha.106.63373

Recurring patterns of atrial fibrillation in surface ECG predict restoration of sinus rhythm by catheter ablation

Background Non-invasive tools to help identify patients likely to benefit from catheter ablation (CA) of atrial fibrillation (AF) would facilitate personalised treatment planning. Aim To investigate atrial waveform organisation through recurrence plot indices (RPI) and their ability to predict CA outcome. Methods One minute 12-lead ECG was recorded before CA from 62 patients with AF (32 paroxysmal AF; 45 men; age 57±10 years). Organisation of atrial waveforms from i) TQ intervals in V1 and ii) QRST suppressed continuous AF waveforms (CAFW), were quantified using RPI: percentage recurrence (PR), percentage determinism (PD), entropy of recurrence (ER). Ability to predict acute (terminating vs. non-terminating AF), 3-month and 6-month postoperative outcome (AF vs. AF free) were assessed. Results RPI either by TQ or CAFW analysis did not change significantly with acute outcome. Patients arrhythmia-free at 6-month follow-up had higher organisation in TQ intervals by PD (

Catheter ablation in patients with atrial fibrillation : mapping refinements, outcome prediction and effect on quality of life

PhD ThesisChapter 1 presents a literature review, focused primarily on the pathophysiology and management of atrial fibrillation (AF). Chapter 2 examines correlations between the dominant frequency of AF - calculated using principal component analysis from a modified surface 12-lead ECG (which included posterior leads), a standard 12-lead ECG and intracardiac recordings from both atria. The inclusion of posterior leads did not improve correlation with left atrial activity because of the dominance of lead V1 in both ECG configurations. Chapter 3 explores whether acute and 12-month outcome following catheter ablation for AF can be predicted beforehand from clinical and surface AF waveform parameters. Multivariate risk scores combining these parameters can predict arrhythmia outcome following ablation, and could therefore be used to identify those most likely to benefit from this therapy. Chapter 4 examines the effect of catheter ablation on AF symptoms and quality of life (QoL). AF symptom and QoL scores improved significantly in patients who maintained sinus rhythm after ablation but did not change in those with recurrent AF. AF-specific QoL scales are more responsive to change and correlate better with ablation outcome. Chapter 5 examines inter-atrial frequency gradients in patients with persistent AF using multipolar contact mapping. A right-to-left atrial frequency gradient was found in a quarter of the patients studied, implying that their arrhythmia was being maintained by high frequency sources in the right rather than the left atrium. Chapter 6 examines whether targeting high frequency and highly repetitive complex fractionated atrial electrogram sites, identified using multipolar contact mapping during persistent AF, resulted in arrhythmia termination and maintenance of sinus rhythm long-term. The utility of administering flecainide to distinguish critical from bystander AF sites was also investigated. Flecainide did not help refine ablation targets and 12-month outcome after targeting these sites was not superior to other ablation strategies

Relationship between body surface potential maps and atrial electrograms in patients with atrial fibrillation

PhD ThesisAtrial fibrillation (AF) is the most common cardiac arrhythmia. It is distinguished by fibrillating or trembling of the atrial muscle instead of normal contraction. Patients in AF have a much higher risk of stroke. AF is often driven by the left atrium (LA) and the diagnosis of AF is normally made from lead V1 in a 12-lead electrocardiogram (ECG). However, lead V1 is dominated by right atrial activity due to its proximal location to the right atrium (RA). Consequently it is not well understood how electrical activity from the LA contributes to the ECG. Studies of the AF mechanisms from the LA are typically based on invasive recording techniques. From a clinical point of view it is highly desirable to have an alternative, non-invasive characterisation of AF. The aim of this study was to investigate how the LA electrical activity was expressed on the body surface, and if it could be observed preferentially in different sites on the body surface. For this purpose, electrical activity of the heart from 20 patients in AF were recorded simultaneously using 64-lead body surface potential mapping (BSPM) and bipolar 10-electrode catheters located in the LA and coronary sinus (CS). Established AF characteristics such as amplitude, dominant frequency (DF) and spectral concentration (SC) were estimated and analysed. Furthermore, two novel AF characteristics (intracardiac DF power distribution, and body surface spectral peak type) were proposed to investigate the relationship between the BSPM and electrogram (EGM) recordings. The results showed that although in individual patients there were body surface sites that preferentially represented the AF characteristics estimated from the LA, those sites were not consistent across all patients. It was found that the left atrial activity could be detected in all body surface sites such that all sites had a dominant or non-dominant spectral peak corresponding to EGM DF. However, overall the results suggested that body surface site 22 (close to lead V1) was more closely representative of the CS activity, and site 49 (close to the posterior lower central right) was more closely representative of the left atrial activity. There was evidence of more accurate estimation of AF characteristics using additional electrodes to lead V1

Noninvasive Assessment of Complexity of Atrial Fibrillation Correlation With Contact Mapping and Impact of Ablation

[EN] Background: It is difficult to noninvasively phenotype atrial fibrillation (AF) in a way that reflects clinical end points such as response to therapy. We set out to map electrical patterns of disorganization and regions of reentrant activity in AF from the body surface using electrocardiographic imaging, calibrated to panoramic intracardiac recordings and referenced to AF termination by ablation. Methods: Bi-atrial intracardiac electrograms of 47 patients with AF at ablation (30 persistent, 29 male, 63 +/- 9 years) were recorded with 64-pole basket catheters and simultaneous 57-lead body surface ECGs. Atrial epicardial electrical activity was reconstructed and organized sites were invasively and noninvasively tracked in 3-dimension using phase singularity. In a subset of 17 patients, sites of AF organization were targeted for ablation. Results: Body surface mapping showed greater AF organization near intracardially detected drivers than elsewhere, both in phase singularity density (2.3 +/- 2.1 versus 1.9 +/- 1.6; P=0.02) and number of drivers (3.2 +/- 2.3 versus 2.7 +/- 1.7; P=0.02). Complexity, defined as the number of stable AF reentrant sites, was concordant between noninvasive and invasive methods (r(2)=0.5; CC=0.71). In the subset receiving targeted ablation, AF complexity showed lower values in those in whom AF terminated than those in whom AF did not terminate (P<0.01). Conclusions: AF complexity tracked noninvasively correlates well with organized and disorganized regions detected by panoramic intracardiac mapping and correlates with the acute outcome by ablation. This approach may assist in bedside monitoring of therapy or in improving the efficacy of ongoing ablation procedures.This article was supported in part by: Instituto de Salud Carlos III FEDER (Fondo Europeo de Desarrollo Regional; IJCI-2014-22178, DTS16/00160; PI14/00857, PI16/01123; PI17/01059; PI17/01106), Generalitat Valenciana Grants (APOSTD/2017 and APOSTD/2018) and projects (GVA/2018/103); National Institutes of Health (Dr Narayan: R01 HL85537; K24 HL103800); EITHealth 19600 AFFINE.Rodrigo Bort, M.; Martínez Climent, BA.; Hernández-Romero, I.; Liberos Mascarell, A.; Baykaner, T.; Rogers, AJ.; Alhusseini, M.... (2020). Noninvasive Assessment of Complexity of Atrial Fibrillation Correlation With Contact Mapping and Impact of Ablation. Circulation Arrhythmia and Electrophysiology. 13(3):236-246. https://doi.org/10.1161/CIRCEP.119.007700S236246133Calkins H Hindricks G Cappato R Kim YH Saad EB Aguinaga L Akar JG Badhwar VBrugada J Camm J etal 2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensusstatement on catheter and surgical ablation of atrial fibrillation: Executive summary. J Arrhythm.2017;33:369-409Narayan SM Krummen DE Clopton P Shivkumar K Miller JM. Direct or coincidentalelimination of stable rotors or focal sources may explain successful atrial fibrillation ablation:on-treatment analysis of the CONFIRM trial (Conventional ablation for AF with or without focalHaissaguerre M Hocini M Denis A Shah AJ Komatsu Y Yamashita S Daly M Amraoui SZellerhoff S Picat MQ etal. Driver domains in persistent atrial fibrillation. Circulation.2014;130:530-8.Atienza F Almendral J Ormaetxe JM Moya A Martínez-Alday JD Hernández-Madrid ACastellanos E Arribas F Arias MÁ Tercedor L etal. Comparison of radiofrequency catheterablation of drivers and circumferential pulmonary vein isolation in atrial fibrillation: aAtienza, F., Almendral, J., Ormaetxe, J. M., Moya, Á., Martínez-Alday, J. D., Hernández-Madrid, A., … Jalife, J. (2014). Comparison of Radiofrequency Catheter Ablation of Drivers and Circumferential Pulmonary Vein Isolation in Atrial Fibrillation. Journal of the American College of Cardiology, 64(23), 2455-2467. doi:10.1016/j.jacc.2014.09.053Seitz J Bars C Théodore G Beurtheret S Lellouche N Bremondy M Ferracci A Faure JPenaranda G Yamazaki M etal. AF Ablation Guided by Spatiotemporal ElectrogramDispersion Without Pulmonary Vein Isolation: A Wholly Patient-Tailored Approach. J Am CollGuillem MS Climent AM Millet J Arenal Á Fernández-Avilés F Jalife J Atienza FBerenfeld O. Noninvasive localization of maximal frequency sites of atrial fibrillation by bodysurface potential mapping. Circ Arrhythm Electrophysiol. 2013;6:294-301.Ramirez FD Birnie DH Nair GM Szczotka A Redpath CJ Sadek MM Nery PB. Efficacyand safety of driver-guided catheter ablation for atrial fibrillation: A systematic review and metaRamirez, F. D., Birnie, D. H., Nair, G. M., Szczotka, A., Redpath, C. J., Sadek, M. M., & Nery, P. B. (2017). Efficacy and safety of driver-guided catheter ablation for atrial fibrillation: A systematic review and meta-analysis. Journal of Cardiovascular Electrophysiology, 28(12), 1371-1378. doi:10.1111/jce.13313Baykaner T Rogers AJ Meckler GL Zaman J Navara R Rodrigo M Alhusseini MKowalewski CAB Viswanathan MN Narayan SM etal. Clinical Implications of Ablation ofDrivers for Atrial Fibrillation: A Systematic Review and Meta-Analysis. Circ ArrhythmBrachmann J Hummel JD Wilber DJ Sarver AE Rapkin J Shpun S Szili-Torok T.Prospective randomized comparison of rotor ablation vs. conventional ablation for treatment ofVijayakumar R Vasireddi SK Cuculich PS Faddis MN Rudy Y. MethodologyConsiderations in Phase Mapping of Human Cardiac Arrhythmias. Circ ArrhythmAlhusseini M Vidmar D Meckler GL Kowalewski CA Shenasa F Wang PJ Narayan SMRappel WJ. Two Independent Mapping Techniques Identify Rotational Activity Patterns at Sitesof Local Termination During Persistent Atrial Fibrillation. J Cardiovasc Electrophysiol.2017;28:615-622.Miller JM Kalra V Das MK Jain R Garlie JB Brewster JA Dandamudi G. Clinical Benefitof Ablating Localized Sources for Human Atrial Fibrillation: The Indiana University FIRMZaman JAB Baykaner T Clopton P Swarup V Kowal RC Daubert JP Day JD Hummel JSchricker AA Krummen DE etal. Recurrent Post-Ablation Paroxysmal Atrial FibrillationShares Substrates With Persistent Atrial Fibrillation: An 11-Center Study. JACC ClinYushkevich PA Zhang H Gee JC. Continuous medial representation for anatomicalstructures. IEEE Trans Med Imaging. 2006;25:1547-64.Remondino F. 3-D reconstruction of static human body shape from image sequence.Remondino, F. (2004). 3-D reconstruction of static human body shape from image sequence. Computer Vision and Image Understanding, 93(1), 65-85. doi:10.1016/j.cviu.2003.08.006Eggert DW Lorusso A Fish RB. Estimating 3-D rigid body transformations: a comparisonRodrigo M Guillem MS Climent AM Pedrón-Torrecilla J Liberos A Millet J FernándezRodrigo, M., Guillem, M. S., Climent, A. M., Pedrón-Torrecilla, J., Liberos, A., Millet, J., … Berenfeld, O. (2014). Body surface localization of left and right atrial high-frequency rotors in atrial fibrillation patients: A clinical-computational study. Heart Rhythm, 11(9), 1584-1591. doi:10.1016/j.hrthm.2014.05.013Rodrigo M Climent AM Liberos A Fernández-Avilés F Berenfeld O Atienza F GuillemMS. Highest dominant frequency and rotor positions are robust markers of driver location duringMS. Technical Considerations on Phase Mapping for Identification of Atrial Reentrant Activityin Direct- and Inverse-Computed Electrograms. Circ Arrhythm Electrophysiol.2017;10:e005008.Castells F Mora C Rieta JJ Moratal-Pérez D Millet J. Estimation of atrial fibrillatory wavefrom single-lead atrial fibrillation electrocardiograms using principal component analysisconcepts. Med Biol Eng Comput. 2005;43:557-560.Rodrigo M Climent AM Liberos A Hernandez-Romero I Arenal A Bermejo J FernandezAviles F Atienza F Guillem MS. Solving Inaccuracies in Anatomical Models forElectrocardiographic Inverse Problem Resolution by Maximizing Reconstruction Quality. IEEERodrigo, M., Climent, A. M., Liberos, A., Hernandez-Romero, I., Arenal, A., Bermejo, J., … Guillem, M. S. (2018). Solving Inaccuracies in Anatomical Models for Electrocardiographic Inverse Problem Resolution by Maximizing Reconstruction Quality. IEEE Transactions on Medical Imaging, 37(3), 733-740. doi:10.1109/tmi.2017.2707413Honarbakhsh S Schilling RJ Providência R Dhillon G Sawhney V Martin CA Keating EFinlay M Ahsan S Chow A etal. 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Performance and limitations of noninvasive cardiac activation mapping. Heart Rhythm, 16(3), 435-442. doi:10.1016/j.hrthm.2018.10.010Rudy Y. Letter to the Editor-ECG imaging and activation mapping. Heart Rhythm. 2019;16:e50-e.Podziemski P Zeemering S Kuklik P van Hunnik A Maesen B Maessen J Crijns HJWillems S Verma A Betts TR Murray S Neuzil P Ince H Steven D Sultan A Heck PMHall MC etal. Targeting Nonpulmonary Vein Sources in Persistent Atrial Fibrillation IdentifiedLim HS Hocini M Dubois R Denis A Derval N Zellerhoff S Yamashita S Berte BMahida S Komatsu Y etal. Complexity and Distribution of Drivers in Relation to Duration ofCamm AJ Breithardt G Crijns H Dorian P Kowey P Le Heuzey JY Merioua I PedrazziniL Prystowsky EN Schwartz PJ etal. Real-life observations of clinical outcomes with rhythmand rate-control therapies for atrial fibrillation RECORDAF (Registry on Cardiac RhythmCamm, A. J., Breithardt, G., Crijns, H., Dorian, P., Kowey, P., Le Heuzey, J.-Y., … Weintraub, W. (2011). 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M., Husser, D., Millet-Roig, J., & Castells, F. (2009). How Many Leads Are Necessary for a Reliable Reconstruction of Surface Potentials During Atrial Fibrillation? IEEE Transactions on Information Technology in Biomedicine, 13(3), 330-340. doi:10.1109/titb.2008.2011894Rodrigo M Climent AM Liberos A Fernández-Aviles F Atienza F Guillem MS BerenfeldO. Minimal configuration of body surface potential mapping for discrimination of left versu

Activation patterns in atrial fibrillation: contributions of body surface potential mapping

La fibrilación auricular (FA) es una de las arritmias cardiacas más comunes, afectando a alrededor del 10 % de los mayores de 70 años. A pesar de su alta incidencia en la población, los mecanismos que desencadenan y mantienen la FA son inciertos. Aunque existen diversos tratamientos quirúrgicos y farmacológicos, el éxito de los tratamientos contra la FA es muy bajo. La causa de esta baja tasa de éxito de las diferentes terapias es que no existen criterios de selección de pacientes que permitan pronosticar qué terapia puede ser más efectiva para cada paciente. Una de las formas que se han propuesto para determinar el grado de gravedad de la arritmia en cada paciente y, por tanto, poder predecir qué tratamiento es el más apropiado es la medida de la organización auricular. Esta tesis doctoral se enmarca dentro de la determinación no invasiva del grado de organización espacial de la activación del miocardio auricular a partir del estudio de registros multiderivación del electrocardiograma de superficie (ECG). El ECG es una representación simplificada del campo eléctrico del corazón basada en las proyecciones de este campo eléctrico en 8 ejes. Esta simplificación es considerada como aceptable en el caso de ritmos no fibrilantes en los que la activación miocárdica puede ser modelada como un dipolo. Sin embargo, su validez no ha sido demostrada para el caso de ritmos fibrilantes en los cuales la asunción de un modelo dipolar es cuestionable. Uno de los objetivos de esta tesis ha sido la evaluación del electrocardiograma de superficie para la obtención de parámetros espaciales de las ondas de FA. Se compararon las representaciones tridimensionales de las ondas de FA registradas a partir de tres derivaciones ortogonales con las representaciones tridimensionales estimadas a partir del ECG, llegando a la conclusión de que estas representaciones estimadas no son fieles a las representaciones registradas. Los resultados de nuestro estudio ponen de manifiesto que la falta de dGuillem Sanchez, MDLS. (2008). Activation patterns in atrial fibrillation: contributions of body surface potential mapping [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/3922Palanci

Non-invasive identification of atrial fibrillation drivers

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias. Nowadays the fibrillatory process is known to be provoked by the high-frequency reentrant activity of certain atrial regions that propagates the fibrillatory activity to the rest of the atrial tissue, and the electrical isolation of these key regions has demonstrated its effectiveness in terminating the fibrillatory process. The location of the dominant regions represents a major challenge in the diagnosis and treatment of this arrhythmia. With the aim to detect and locate the fibrillatory sources prior to surgical procedure, non-invasive methods have been developed such as body surface electrical mapping (BSPM) which allows to record with high spatial resolution the electrical activity on the torso surface or the electrocardiographic imaging (ECGI) which allows to non-invasively reconstruct the electrical activity in the atrial surface. Given the novelty of these systems, both technologies suffer from a lack of scientific knowledge about the physical and technical mechanisms that support their operation. Therefore, the aim of this thesis is to increase that knowledge, as well as studying the effectiveness of these technologies for the localization of dominant regions in patients with AF. First, it has been shown that BSPM systems are able to noninvasively identify atrial rotors by recognizing surface rotors after band-pass filtering. Furthermore, the position of such surface rotors is related to the atrial rotor location, allowing the distinction between left or right atrial rotors. Moreover, it has been found that the surface electrical maps in AF suffer a spatial smoothing effect by the torso conductor volume, so the surface electrical activity can be studied with a relatively small number of electrodes. Specifically, it has been seen that 12 uniformly distributed electrodes are sufficient for the correct identification of atrial dominant frequencies, while at least 32 leads are needed for non-invasive identification of atrial rotors. Secondly, the effect of narrowband filtering on the effectiveness of the location of reentrant patterns was studied. It has been found that this procedure allows isolating the reentrant electrical activity caused by the rotor, increasing the detection rate for both invasive and surface maps. However, the spatial smoothing caused by the regularization of the ECGI added to the temporal filtering causes a large increase in the spurious reentrant activity, making it difficult to detect real reentrant patterns. However, it has been found that maps provided by the ECGI without temporal filtering allow the correct detection of reentrant activity, so narrowband filtering should be applied for intracavitary or surface signal only. Finally, we studied the stability of the markers used to detect dominant regions in ECGI, such as frequency maps or the rotor presence. It has been found that in the presence of alterations in the conditions of the inverse problem, such as electrical or geometrical noise, these markers are significantly more stable than the ECGI signal morphology from which they are extracted. In addition, a new methodology for error reduction in the atrial spatial location based on the curvature of the curve L has been proposed. The results presented in this thesis showed that BSPM and ECGI systems allows to non-invasively locate the presence of high-frequency rotors, responsible for the maintenance of AF. This detection has been proven to be unambiguous and robust, and the physical and technical mechanisms that support this behavior have been studied. These results indicate that both non-invasive systems provide information of great clinical value in the treatment of AF, so their use can be helpful for selecting and planning atrial ablation procedures.La fibrilación auricular (FA) es una de las arritmias cardiacas más frecuentes. Hoy en día se sabe que el proceso fibrilatorio está provocado por la actividad reentrante a alta frecuencia de ciertas regiones auriculares que propagan la actividad fibrilatoria en el resto del tejido auricular, y se ha demostrado que el aislamiento eléctrico de estas regiones dominantes permite detener el proceso fibrilatorio. La localización de las regiones dominantes supone un gran reto en el diagnóstico y tratamiento de la FA. Con el objetivo de poder localizar las fuentes fibrilatorias con anterioridad al procedimiento quirúrgico, se han desarrollado métodos no invasivos como la cartografía eléctrica de superficie (CES) que registra con gran resolución espacial la actividad eléctrica en la superficie del torso o la electrocardiografía por imagen (ECGI) que permite reconstruir la actividad eléctrica en la superficie auricular. Dada la novedad de estos sistemas, existe una falta de conocimiento científico sobre los mecanismos físicos y técnicos que sustentan su funcionamiento. Por lo tanto, el objetivo de esta tesis es aumentar dicho conocimiento, así como estudiar la eficacia de ambas tecnologías para la localización de regiones dominantes en pacientes con FA. En primer lugar, ha visto que los sistemas CES permiten identificar rotores auriculares mediante el reconocimiento de rotores superficiales tras el filtrado en banda estrecha. Además, la posición de los rotores superficiales está relacionada con la localización de dichos rotores, permitiendo la distinción entre rotores de aurícula derecha o izquierda. Por otra parte, se ha visto que los mapas eléctricos superficiales durante FA sufren una gran suavizado espacial por el efecto del volumen conductor del torso, lo que permite que la actividad eléctrica superficial pueda ser estudiada con un número relativamente reducido de electrodos. Concretamente, se ha visto que 12 electrodos uniformemente distribuidos son suficientes para una correcta identificación de frecuencias dominantes, mientras que son necesarios al menos 32 para una correcta identificación de rotores auriculares. Por otra parte, también se ha estudiado el efecto del filtrado en banda estrecha sobre la eficacia de la localización de patrones reentrantes. Así, se ha visto que este procedimiento permite aislar la actividad eléctrica reentrante provocada por el rotor, aumentando la tasa de detección tanto para señal obtenida de manera invasiva como para los mapas superficiales. No obstante, este filtrado temporal sobre la señal de ECGI provoca un gran aumento de la actividad reentrante espúrea que dificulta la detección de patrones reentrantes reales. Sin embargo, los mapas ECGI sin filtrado temporal permiten la detección correcta de la actividad reentrante, por lo el filtrado debería ser aplicado únicamente para señal intracavitaria o superficial. Por último, se ha estudiado la estabilidad de los marcadores utilizados en ECGI para detectar regiones dominantes, como son los mapas de frecuencia o la presencia de rotores. Se ha visto que en presencia de alteraciones en las condiciones del problema inverso, como ruido eléctrico o geométrico, estos marcadores son significativamente más estables que la morfología de la propia señal ECGI. Además, se ha propuesto una nueva metodología para la reducción del error en la localización espacial de la aurícula basado en la curvatura de la curva L. Los resultados presentados en esta tesis revelan que los sistemas de CES y ECGI permiten localizar de manera no invasiva la presencia de rotores de alta frecuencia. Esta detección es univoca y robusta, y se han estudiado los mecanismos físicos y técnicos que sustentan dicho comportamiento. Estos resultados indican que ambos sistemas no invasivos proporcionan información de gran valor clínico en el tratamiento de la FA, por lo que su uso puede ser de gran ayuda para la selección y planificaciLa fibril·lació auricular (FA) és una de les arítmies cardíaques més freqüents. Hui en dia es sabut que el procés fibrilatori està provocat per l'activitat reentrant de certes regions auriculars que propaguen l'activitat fibril·latoria a la resta del teixit auricular, i s'ha demostrat que l'aïllament elèctric d'aquestes regions dominants permet aturar el procés fibrilatori. La localització de les regions dominants suposa un gran repte en el diagnòstic i tractament d'aquesta arítmia. Amb l'objectiu de poder localitzar fonts fibril·latories amb anterioritat al procediment quirúrgic s'han desenvolupat mètodes no invasius com la cartografia elèctrica de superfície (CES) que registra amb gran resolució espacial l'activitat elèctrica en la superfície del tors o l'electrocardiografia per imatge (ECGI) que permet obtenir de manera no invasiva l'activitat elèctrica en la superfície auricular. Donada la relativa novetat d'aquests sistemes, existeix una manca de coneixement científic sobre els mecanismes físics i tècnics que sustenten el seu funcionament. Per tant, l'objectiu d'aquesta tesi és augmentar aquest coneixement, així com estudiar l'eficàcia d'aquestes tecnologies per a la localització de regions dominants en pacients amb FA. En primer lloc, s'ha vist que els sistemes CES permeten identificar rotors auriculars mitjançant el reconeixement de rotors superficials després del filtrat en banda estreta. A més, la posició dels rotors superficials està relacionada amb la localització d'aquests rotors, permetent la distinció entre rotors de aurícula dreta o esquerra. També s'ha vist que els mapes elèctrics superficials durant FA pateixen un gran suavitzat espacial per l'efecte del volum conductor del tors, el que permet que l'activitat elèctrica superficial pugui ser estudiada amb un nombre relativament reduït d'elèctrodes. Concretament, s'ha vist que 12 elèctrodes uniformement distribuïts són suficients per a una correcta identificació de freqüències dominants auriculars, mentre que són necessaris almenys 32 per a una correcta identificació de rotors auriculars. D'altra banda, també s'ha estudiat l'efecte del filtrat en banda estreta sobre l'eficàcia de la localització de patrons reentrants. Així, s'ha vist que aquest procediment permet aïllar l'activitat elèctrica reentrant provocada pel rotor, augmentant la taxa de detecció tant pel senyal obtingut de manera invasiva com per als mapes superficials. No obstant això, aquest filtrat temporal sobre el senyal de ECGI provoca un gran augment de l'activitat reentrant espúria que dificulta la detecció de patrons reentrants reals. A més, els mapes proporcionats per la ECGI sense filtrat temporal permeten la detecció correcta de l'activitat reentrant, per la qual cosa el filtrat hauria de ser aplicat únicament per a senyal intracavitària o superficial. Per últim, s'ha estudiat l'estabilitat dels marcadors utilitzats en ECGI per a detectar regions auriculars dominants, com són els mapes de freqüència o la presència de rotors. S'ha vist que en presència d'alteracions en les condicions del problema invers, com soroll elèctric o geomètric, aquests marcadors són significativament més estables que la morfologia del mateix senyal ECGI. A més, s'ha proposat una nova metodologia per a la reducció de l'error en la localització espacial de l'aurícula basat en la curvatura de la corba L. Els resultats presentats en aquesta tesi revelen que els sistemes de CES i ECGI permeten localitzar de manera no invasiva la presència de rotors d'alta freqüència. Aquesta detecció és unívoca i robusta, i s'han estudiat els mecanismes físics i tècnics que sustenten aquest comportament. Aquests resultats indiquen que els dos sistemes no invasius proporcionen informació de gran valor clínic en el tractament de la FA, pel que el seu ús pot ser de gran ajuda per a la selecció i planificació de procediments d'ablació auricular.Rodrigo Bort, M. (2016). Non-invasive identification of atrial fibrillation drivers [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/75346TESISPremios Extraordinarios de tesis doctorale

Estimation of Atrial Electrical Complexity during Atrial Fibrillation by Solving the Inverse Problem of Electrocardiography

Tesis por compendio[ES] La fibrilación auricular (FA) es la arritmia más prevalente en el mundo y está asociada con una elevada morbilidad, mortalidad y costes sanitarios. A pesar de los avances en opciones de tratamiento farmacológico y terapia de ablación, el manejo de la FA todavía tiene margen de mejora. La imagen electrocardiográfica (ECGI) se ha destacado como un prometedor método no invasivo para evaluar la electrofisiología cardíaca y guiar las decisiones terapéuticas en casos de fibrilación auricular. No obstante, el ECGI se enfrenta a desafíos como la necesidad de resolver de manera precisa el denominado problema inverso de la electrocardiografía y de optimizar la calidad de las reconstrucciones de ECGI. Además, la integración del ECGI en los procesos clínicos rutinarios sigue siendo un reto, en gran medida debido a los costos que supone la necesidad de imágenes cardíacas. Por ello, los objetivos principales de esta tesis doctoral son impulsar la tecnología ECGI mediante la determinación de sus requisitos técnicos mínimos y la mejora de las metodologías existentes para obtener señales de ECGI precisas. Asimismo, buscamos evaluar la capacidad de ECGI para cuantificar de forma no invasiva la complejidad de la FA. Para lograr estos objetivos, se han llevado a cabo diversos estudios a lo largo de la tesis, desde el perfeccionamiento del ECGI hasta la evaluación de la FA utilizando esta tecnología. En primer lugar, se han estudiado los requisitos geométricos y de señal del problema inverso mediante el estudio de los efectos de la densidad de la malla del torso y la distribución de electrodos en la precisión del ECGI, lo que ha conducido a la identificación del número mínimo de nodos y su distribución en la malla del torso. Además, hemos identificado que para obtener señales de ECGI de alta calidad, es crucial la correcta disposición de los electrodos en la malla del torso reconstruido. Asimismo, se ha definido y evaluado una nueva metodología de ECGI sin necesidad de usar técnicas de imagen cardiaca. Para ello, hemos comparado métricas derivadas del ECGI calculadas con la geometría original del corazón de los pacientes con las métricas medidas en diferentes geometrías cardíacas. Nuestros resultados han mostrado que el ECGI sin necesidad de imágenes cardíacas es efectivo para la correcta cuantificación y localización de los patrones y zonas que mantienen la FA. En paralelo, hemos optimizado la regularización de Tikhonov de orden cero actual y la optimización de la curva L para el cálculo de las señales ECGI, investigando cómo el ruido eléctrico y las incertidumbres geométricas influyen en la regularización. A partir de ello, propusimos un nuevo criterio que realza la precisión de las soluciones de ECGI en escenarios con incertidumbre debido a condiciones de señal no ideales. En segundo lugar, en esta tesis doctoral, se han llevado a cabo múltiples análisis relativos a diferentes metodologías de procesado de señales y obtención métricas derivadas del ECGI con el fin de caracterizar mejor el sustrato cardíaco y la actividad reentrante en las señales de ECGI de pacientes con FA. Con el objetivo de obtener una comprensión más profunda de los mecanismos electrofisiológicos subyacentes a la FA, hemos establecido la estrategia de filtrado óptima para extraer patrones reentrantes específicos del paciente y métricas derivadas de señales ECGI. Además, hemos investigado la reproducibilidad de los mapas de reentradas derivados de las señales de ECGI y hemos encontrado su relación con el éxito de la ablación de venas pulmonares (PVI). Nuestros resultados han mostrado que una mayor reproducibilidad en los patrones reentrantes de FA detectados con ECGI está relacionada con el éxito de la PVI, creando una metodología para estratificar a los pacientes con FA antes de los procedimientos de ablación.[CA] La fibril·lació auricular (FA) és l'arrítmia més prevalent al món i està associada amb una elevada morbiditat, mortalitat i costos sanitaris. Malgrat els avanços en opcions de tractament farmacològic i teràpies d'ablació, el maneig de la FA encara té marge de millora. La imatge electrocardiogràfica (ECGI) s'ha destacat com un prometedor mètode no invasiu per a avaluar l'electrofisiologia cardíaca i guiar les decisions terapèutiques en casos de fibril·lació auricular. No obstant això, l'ECGI s'enfronta a desafiaments com la necessitat de resoldre de manera precisa el denominat problema invers de la electrocardiografia i d'optimitzar la qualitat de les reconstruccions de ECGI. A més, la integració del ECGI en els processos clínics rutinaris continua sent un repte, en gran manera a causa dels costos que suposa la necessitat d'imatges cardíaques. Per això, els objectius principals d'aquesta tesi doctoral són impulsar la tecnologia de l'ECGI mitjançant la determinació dels seus requisits tècnics mínims i la millora de les metodologies existents per obtenir senyals d'ECGI precises. A més, busquem avaluar la capacitat de l'ECGI per quantificar de forma no invasiva la complexitat de la FA. Per a aconseguir aquests objectius, s'han dut a terme diversos estudis al llarg de la tesi, des del perfeccionament de l'ECGI fins a l'avaluació de la FA utilitzant aquesta tecnologia. En primer lloc, hem estudiat els requisits geomètrics i de senyal del problema invers mitjançant l'estudi dels efectes de la densitat de la malla del tors i la distribució d'elèctrodes en la precisió de l'ECGI, el que ha conduït a la identificació del nombre mínim de nodes i la seva distribució en la malla del tors. A més, hem identificat que per obtindre senyals d'ECGI d'alta qualitat, és crucial la correcta disposició dels elèctrodes en la malla del tors reconstruïda. També s'ha definit i avaluat una nova metodologia d'ECGI sense necessitat d'utilitzar tècniques d'imatge cardíaca. Per a això, hem comparat mètriques derivades de l'ECGI calculades amb la geometria original del cor dels pacients amb les mètriques mesurades en diferents geometries cardíaques. Els nostres resultats han mostrat que l'ECGI sense necessitat d'imatges cardíaques és efectiu per a la correcta quantificació i localització dels patrons i zones que mantenen la FA. Paral·lelament, hem optimitzat la regularització de Tikhonov d'ordre zero actual i l'optimització de la corba L per al càlcul de les senyals d'ECGI, investigant com el soroll elèctric i les incerteses geomètriques influeixen en la regularització. Addicionalment, vam proposar un nou criteri que reforça la precisió de les solucions d'ECGI en escenaris amb incertesa degut a condicions de senyal no ideals. En segon lloc, en aquesta tesi doctoral, s'han dut a terme múltiples anàlisis relatius a diferents metodologies de processament de senyals i obtenció de mètriques derivades de l'ECGI amb l'objectiu de caracteritzar millor el substrat cardíac i l'activitat reentrant en les senyals d'ECGI de pacients amb FA. Amb l'objectiu d'obtindre una comprensió més profunda dels mecanismes electrofisiològics subjacents a la FA, hem establert l'estratègia de filtrat òptima per extreure patrons reentrants específics del pacient i mètriques derivades de senyals ECGI. A més, hem investigat la reproductibilitat dels mapes de reentrades derivats de les senyals d'ECGI i hem trobat la seva relació amb l'èxit de l'ablació de venes pulmonars (PVI). Els nostres resultats han mostrat que una major reproductibilitat en els patrons reentrants de FA detectats amb ECGI està relacionada amb l'èxit de la PVI, creant una metodologia per estratificar els pacients amb FA abans dels procediments d'ablació.[EN] Atrial fibrillation (AF) is the most prevalent arrhythmia in the world and is associated with significant morbidity, mortality, and healthcare costs. Despite advancements in pharmaceutical treatment alternatives and ablation therapy, AF management remains suboptimal. Electrocardiographic Imaging (ECGI) has emerged as a promising non-invasive method for assessing cardiac electrophysiology and guiding therapeutic decisions in atrial fibrillation. However, ECGI faces challenges in dealing with accurately resolving the ill-posed inverse problem of electrocardiography and optimizing the quality of ECGI reconstructions. Additionally, the integration of ECGI into clinical workflows is still a challenge that is hindered by the associated costs arising from the need for cardiac imaging. For this purpose, the main objectives of this PhD thesis are to advance ECGI technology by determining the minimal technical requirements and refining existing methodologies for acquiring accurate ECGI signals. In addition, we aim to assess the capacity of ECGI for noninvasively quantifying AF complexity. To fulfill these objectives, several studies were developed throughout the thesis, advancing from ECGI enhancement to AF evaluation using ECGI. Firstly, geometric and signal requirements of the inverse problem were addressed by studying the effects of torso mesh density and electrode distribution on ECGI accuracy, leading to the identification of the minimal number of nodes and their distribution on the torso mesh. Besides, we identified that the correct location of the electrodes on the reconstructed torso mesh is critical for the accurate ECGI signal obtention. Additionally, a new methodology of imageless ECGI was defined and assessed by comparing ECGI-derived drivers computed with the original heart geometry of the patients to the drivers measured in different heart geometries. Our results showed the ability of imageless ECGI to the correct quantification and location of atrial fibrillation drivers, validating the use of ECGI without the need for cardiac imaging. Also, the current state of-the-art zero-order Tikhonov regularization and L-curve optimization for computing ECGI signals were improved by investigating the impact of electrical noise and geometrical uncertainties on the regularization. We proposed a new criterion that enhances the accuracy and reliability of ECGI solutions in situations with uncertainty from unfavorable signal conditions. Secondly, in this PhD thesis, several analyses, signal processing methodologies, and ECGIderived metrics were investigated to better characterize the cardiac substrate and reentrant activity in ECGI signals from AF patients. With the objective of obtaining a deeper understanding of the electrophysiological mechanisms underlying AF, we established the optimal filtering strategy to extract patient-specific reentrant patterns and derived metrics in ECGI signals. Furthermore, we investigated the reproducibility of the obtained ECGI-reentrant maps and linked them to the success of PVI ablation. Our results showed that higher reproducibility on AF drivers detected with ECGI is linked with the success of PVI, creating a proof-of-concept mechanism for stratifying AF patients prior to ablation procedures.This work was supported by: Instituto de Salud Carlos III, and Ministerio de Ciencia e Innovación (supported by FEDER Fondo Europeo de Desarrollo Regional DIDIMO PLEC2021- 007614, ESSENCE PID2020-119364RB-I00, and RYC2018- 024346B-750), EIT Health (Activity code SAVE-COR 220385, EIT Health is supported by EIT, a body of the European Union) and Generalitat Valenciana Conselleria d’Educació, Investigació, Cultura i Esport (ACIF/2020/265 and BEFPI/2021/062).Molero Alabau, R. (2023). Estimation of Atrial Electrical Complexity during Atrial Fibrillation by Solving the Inverse Problem of Electrocardiography [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/199029Compendi

Predictive value of unshielded magnetocardiographic mapping to differentiate atrial fibrillation patients from healthy subjects

Background: P‐wave duration, its dispersion and signal‐averaged ECG, are currently used markers of vulnerability to atrial fibrillation (AF). However, since tangential atrial currents are better detectable at the body surface as magnetic than electric signals, we investigated the accuracy of magnetocardiographic mapping (MCG), recorded in unshielded clinical environments, as predictor of AF occurrence. Methods: MCG recordings, in sinus rhythm (SR), of 71 AF patients and 75 controls were retrospectively analyzed. Beside electric and magnetic P‐wave and PR interval duration, two MCG P‐wave subintervals, defined P‐dep and P‐rep, were measured, basing on the point of inversion of atrial magnetic field (MF). Eight parameters were calculated from inverse solution with “Effective Magnetic Dipole (EMD) model” and 5 from “MF Extrema” analysis. Discriminant analysis (DA) was used to assess MCG predictive accuracy to differentiate AF patients from controls. Results: All but one (P‐rep) intervals were significantly longer in AF patients. At univariate analysis, three EMD parameters differed significantly: in AF patients, the dipole‐ angle‐elevation angular speed was lower during P‐dep (p &lt; 0.05) and higher during P‐rep (p &lt; 0.001) intervals. The space‐trajectory during P‐rep and the angledynamics during P‐dep were higher (p &lt; 0.05), whereas ratio‐dynamics P‐dep was lower (p &lt; 0.01), in AF. At DA, with a combination of MCG and clinical parameters, 81.5% accuracy in differentiating AF patients from controls was achieved. At Cox‐regression, the angle‐dynamics P‐dep was an independent predictor of AF recurrences (p = 0.037). Conclusions: Quantitative analysis of atrial MF dynamics in SR and the solution of the inverse problem provide new sensitive markers of vulnerability to AF