Beat-to-beat variability in the tricuspid annulus dimensions and dynamics is markedly increased in atrial fibrillation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J Naser ◽  
A Ciobanu ◽  
S Wen ◽  
J Thaden ◽  
V Nkomo ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Tricuspid Valve ◽  
Cycle Length ◽  
Cardiac Cycle ◽  
Absolute Difference ◽  
Funding Source ◽  
Accurate Assessment ◽  
Tricuspid Annulus ◽  
Median Absolute Difference

Abstract Background Atrial fibrillation (Afib) leads to beat-to-beat variability in cycle length; however, whether there is associated beat-to-beat variability in the tricuspid annulus (TA) dimensions or variability in the time in cardiac cycle when TA reaches maximal size is unknown. Purpose We aim to assess the beat-to-beat variability in the TA dimensions in Afib compared with sinus rhythm (SR). Methods Images were obtained from 58 patients (29 in Afib, 29 in SR) undergoing either 3D TTE or TEE examination. We measured TA in 3–6 cardiac cycles per patient using commercially available software (TomTec 4MV). Results Median absolute difference in maximal TA area over 3–6 cardiac cycles was 1.60 cm2 (range 0.35 cm2 to 4.08 cm2) in Afib vs. 1.17 cm2 (range 0.32 cm2 to 2.19 cm2) in SR, p=0.0063. Median absolute difference in the maximal circumference was 0.79 cm (range 0.09 cm to 2.2 cm) in Afib vs 0.54 cm (range 0.12 cm to 1.43 cm) in SR, p=0.0175. A total of 118 cardiac cycles were analyzed in patients in SR and 147 in Afib. Timing of maximal TA area was most commonly recorded at end-diastole (80–100% of the R-R interval) in 62% of cycles in SR; however, it was distributed over a broad range in Afib, p<0.0001, [Figure]. Conclusion Afib leads to significant beat-to-beat variability in the maximal TA area, minimal TA area, maximal TA circumference, and in the time of maximal TA area. These findings suggest that accurate assessment of TA dimensions should be based on continuous tracking of the TA over several cardiac cycles, especially in patients with Afib. These observations have significant implications for device sizing in percutaneous tricuspid valve interventions. Timing of Maximal TA Area Funding Acknowledgement Type of funding source: None

scholarly journals Atrial fibrillation is associated with large beat-to-beat variability in mitral and tricuspid annulus dimensions

2021 ◽  
Author(s):  
Jwan A Naser ◽  
Hilal Olgun Kucuk ◽  
Andrea O Ciobanu ◽  
Hayan Jouni ◽  
Didem Oguz ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Tricuspid Valve ◽  
Mitral Annulus ◽  
Absolute Difference ◽  
Time Interval ◽  
Tricuspid Annulus ◽  
Maximal Size ◽  
Valve Diseases ◽  
Median Absolute Difference ◽  
Selection Of

Abstract Aims Beat-to-beat variability in cycle length is well-known in atrial fibrillation (Afib); whether this also translates to variability in annulus size remains unknown. Defining annulus maximal size in Afib is critical for accurate selection of percutaneous devices given the frequent association with mitral and tricuspid valve diseases. Methods and results Images were obtained from 170 patients undergoing 3D echocardiography [100 (50 sinus rhythm (SR) and 50 Afib) for mitral annulus (MA) and 70 (35 SR and 35 Afib) for tricuspid annulus (TA)]. Images were analysed for differences in annular dynamics with a commercially available software. Number of cardiac cycles analysed was 567 in mitral valve and 346 in tricuspid valve. Median absolute difference in maximal MA area over four to six cycles was 1.8 cm2 (range 0.5–5.2 cm2) in Afib vs. 0.8 cm2 (range 0.1–2.9 cm2) in SR, P < 0.001. Maximal MA area was observed within 30–70% of the R-R interval in 81% of cardiac cycles in SR and in 73% of cycles in Afib. Median absolute difference in maximal TA area over four to six cycles was 1.4 cm2 (range 0.5–3.6 cm2) in Afib vs. 0.7 cm2 (range 0.3–1.7 cm2) in SR, P < 0.001. Maximal TA area was observed within 60–100% of the R-R interval in 81% of cardiac cycles in SR, but only in 49% of cycles in Afib. Conclusion MA and TA reach maximal size within a broad time interval centred around end-systole and end-diastole, respectively, with significant beat-to-beat variability. Afib leads to a larger beat-to-beat variability in both timing of occurrence and values of annulus size than in SR.

A cool modality to restore sinus rhythm

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
O Yasin ◽  
A Sugrue ◽  
M Van Zyl ◽  
A Ladejobi ◽  
J Tri ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Body Temperature ◽  
Sinus Rhythm ◽  
Animal Experiments ◽  
Funding Source ◽  
Atrial Pacing ◽  
Exact Test ◽  
Chi Squared ◽  
Cool Device ◽  
Atrial Defibrillation

Abstract Background Slowing electrical conduction by cooling the myocardium can be used for defibrillation. We previously demonstrated the efficacy of a small cold device placed in oblique sinus (OS) in terminating atrial fibrillation (AF). However, the parameters needed to achieve effective atrial defibrillation are unknown. Purpose Assess effect of the size of cooled myocardium on frequency of AF termination in acute canine animal models. Methods Sternotomy was performed under general anesthesia in 10 acute canine experiments. AF was induced using rapid atrial pacing and intra-myocardial epinephrine and acetylcholine injections. Once AF sustained for at least 30s, either a cool (7–9°C) or placebo (body temperature) device was placed in the OS. Four device sizes were tested; ½X½, ¾X¾, and 1X1 inch devices and two ¾X¾ inch devices placed side by side simultaneously. Time to AF termination was recorded. Chi-squared or Fisher's exact test were used to compare the frequency of arrhythmia termination with cooling versus placebo. Results A total of 166 applications were performed (89 cool vs 77 placebo) in 10 animal experiments. Overall, AF terminated in 82% of the cooling applications vs. 67.5% of placebo (P=0.03, Figure 1). For the ½X½ inch device 88% of cold applications restored sinus rhythm vs. 63.6% for placebo (P=0.05). The frequency of sinus restoration for cold ¾X¾, 1X1 and two ¾X¾ side by side devices was 86.7%, 83.3% and 70% respectively. Time to sinus restoration when achieved was within three minutes was also not significantly changed. Conclusion Placing a cool device in the oblique sinus can terminate AF and efficacy is not affected by the size of device. Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): MediCool Technologies

The role of epicardial fat tissue in atrial fibrillation onset in patients with hypertension

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Tarzimanova ◽  
V.I Podzolkov ◽  
M.V Pisarev ◽  
R.G Gataulin ◽  
K.A Oganesian
Keyword(s):  
Atrial Fibrillation ◽  
Plasma Concentration ◽  
Sinus Rhythm ◽  
Epicardial Fat ◽  
Funding Source ◽  
Fat Tissue ◽  
Hypertensive Patients ◽  
Group I ◽  
Epicardial Fat Tissue ◽  
Group Ii

Abstract Aim To study the influence of epicardial fat tissue (EFT) on atrial fibrillation (AF) occurrence in hypertensive patients. Materials and methods The study included 195 patients with hypertension aged from 38 to 72 years (mean age was 61.5±1.8 years). All patients were divided into two groups: group I included 95 hypertensive patients with paroxysmal AF; 100 patients with hypertension in sinus rhythm were enrolled into group II. Echocardiography was performed to evaluate the thickness of EFT in a parasternal long-axis view. The EFT volume was assessed with computed tomography (CT) scan. The plasma concentration of tissue inhibitor of metalloproteinase-1 (TIMP-1) and metalloproteinase-9 (MMP-9) was measured to evaluate the myocardial fibrosis process. Results There was no significant difference between the studied groups of patients in body mass index: 34.43±1.2 kg/m2 in group I vs 31.97±1.67 kg/m2 in the group II. Waist circumference was significantly higher in group I in comparison with the group II patients: 118.9±3.3 cm vs 110.2±1.4 cm, respectively (p=0.038). EFT thickness was significantly higher in patients with paroxysmal AF (11.6±0.8 mm) in comparison with the patients in sinus rhythm (8.6±0.4 mm) (p<0.001). In group I patients a significant increase of EFT volume (4.6±0.4) in comparison with II group (3.5±0.25) (p=0.002) was noted. A significant positive correlation was revealed in hypertensive patients with paroxysmal AF between EFT volume and left atrial (LA) volume (r=0.7, p=0.022). Also, the plasma concentrations of TIMP-1 and MMP-1 were significantly higher in patients with paroxysmal AF and hypertension. There was a strong positive correlation between EFT volume and plasma concentration of TIMP-1 (r=0.72; p=0.01) and between the EFT volume and the LA volume (r=0.7, p=0.022) in group I patients. Multivariate regression analysis revealed the significant influence of increased EFT thickness more than 10 mm (prevalence ratio (PR) 4.1; 95% CI 1.1; 15.6) and EFT volume more than 6 ml (PR 3.7; 95% CI 1.0; 14.2) on AF occurrence. Conclusion Increased EFT thickness (more than 10 mm) and EFT volume (more than 6 ml) are predictors of AF onset in hypertensive patients. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): The complex subject of the Department

scholarly journals Termination of atrial fibrillation during pharmacological cardioversion in the goat requires inter-atrial synchronisation of conduction

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
V Sobota ◽  
A Van Hunnik ◽  
S Zeemering ◽  
G Gatta ◽  
D Opacic ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Left Atrium ◽  
Conduction Velocity ◽  
Right Atrium ◽  
Path Length ◽  
Cycle Length ◽  
Final Phase ◽  
Periodic Activity ◽  
Bachmann’S Bundle

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ITN Networks PersonalizeAF: Personalized Therapies for Atrial Fibrillation. A Translational Approach, No. 860974; CATCH ME: Characterizing Atrial fibrillation by Translating its Causes into Health Modifiers in the Elderly, No. 633196; MAESTRIA: Machine Learning and Artificial Intelligence for Early Detection of Stroke and Atrial Fibrillation, No. 965286; AFib-TrainNet: EU Training Network on Novel Targets and Methods in Atrial Fibrillation, No. 675351 Netherlands Heart Foundation: CVON2014-09, RACE V Reappraisal of Atrial Fibrillation: Interaction between hyperCoagulability, Electrical remodeling, and Vascular Destabilization in the Progression of Atrial Fibrillation Background Few studies report on mechanisms leading to termination of atrial fibrillation (AF). Purpose To characterise electrophysiological parameters and conduction patterns during the transition from AF to sinus rhythm under various conditions of AF termination. Methods A retrospective evaluation of 6 goat studies was performed. AF was maintained for 3-4 weeks in 29 animals. Four animals were in SR. Unipolar electrograms were acquired with one 249-electrode array/atrium. Pharmacological termination of AF was evoked by various drugs; AP14145 (n = 5), PA6 (n = 7), XAF-1407 (n = 9) vernakalant (n = 8). In animals with sinus rhythm, AF was acutely induced and terminated spontaneously. Baseline AF and ≤3 recordings of the last 10 seconds preceding AF termination were analysed. Intervals with temporal continuous and periodic activity were distinguished in the recordings. AF cycle length (AFCL), conduction velocity and path length were determined for each interval. Results In total, 85 AF terminations were recorded. Switches between temporal continuous and periodic activity were seen frequently during AF. However, termination of AF was always preceded by a phase of periodic activity (PA). The final phase of PA persisted for a median number of 21 [IQR 10-28] cycles in the left atrium and somewhat shorter in the right atrium, Table 1. This final phase of PA was accompanied by a profound bi-atrial increase of AFCL, conduction velocity and path length and a disappearance of inter-atrial cycle length differences. Equipotent changes were not observed in the preceding PAs. During the final AF beats, the number of wave fronts were low, 1 or 2. Interestingly, 92% of the patterns during the last beats of AF involved the Bachmann’s bundle as main source of atrial conduction. Conclusion AF termination is preceded by an increased organisation of fibrillatory conduction, associated with abrupt prolongation of the path length. Propagation in atrial free walls regularly originated from the Bachmann’s bundle. These findings suggest that AF termination was not a random process but follows common spatiotemporal patterns. Final period of temporal organisation Left atrium Right atrium Final PA start Final PA end Final PA start Final PA end Af cycle length (ms) 163 ± 37 204 ± 50* 146 ± 44 207 ± 49* Conduction velocity (cm/s) 77 ± 15 96 ± 25* 83 ± 20 103 ± 24* Path Length (cm) 12.2 ± 2.7 19.3 ± 6.3* 12.0 ± 4.1 21.2 ± 6.4* Length of final periodic activity (beats) NA 21 [IQR 10-28] NA 15 [IQR 10- 25] Electrophysiological changes during the final period periodic activity (PA). Wilcoxon signed rank test. *p <0.05NA= not available

scholarly journals Distinguishing sinus rhythm from atrial fibrillation on single-lead ECGs using a deep neural network

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Oudkerk Pool ◽  
B.D De Vos ◽  
J.M Wolterink ◽  
S Blok ◽  
M.J Schuuring ◽  
...  
Keyword(s):  
Neural Network ◽  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Roc Curve ◽  
Model Development ◽  
Independent Set ◽  
Funding Source ◽  
National Budget ◽  
Validation Set ◽  
Public Grant

Abstract Background The growing availability of mobile phones increases the popularity of portable telemonitoring devices. An atrial fibrillation diagnosis can be reached with a recording of 30s on such telemonitoring devices. However, current commercially available automatic algorithms still require approval by experts. Purpose In this research we aimed to build an artificial intelligence (AI) algorithm to improve automatic distinction of atrial fibrillation (AF) from sinus rhythm (SR), to ultimately save time, costs, and to facilitate telemonitoring programs. Methods We developed a deep convolutional neural network (CNN), based on a residual neural network (ResNet), tailored to single-lead ECG analysis. The CNN was trained using publicly available single-lead ECGs from the 2017 PhysioNet/ Computing in Cardiology Challenge. This dataset consists of 60% SR, 9% AF, 30% alternative rhythm, and 1% noise ECGs. The 8528 available ECGs were divided into a training (90%) and validation set (10%) for model development and hyperparameter optimization. Results The trained CNN was applied to an independent set containing single-lead ECGs of 600 patients equally divided into two groups: SR and AF. Both groups comprised of 300 unique ECGs (SR; 60% male, 63±11 years, AF; 38% male, 56±14 years). In distinguishing between AF and SR, the method achieved an accuracy of 0.92, an F1-score of 0.91, and area under the ROC-curve of 0.98. Conclusion The results demonstrate that distinguishing SR and AF by a fully automatic AI algorithm is feasible. This approach has the potential to reduce cost by minimizing expert supervision, especially when extending the algorithm to other heart rhythms, like premature atrial/ventricular contractions and atrial flutter. Figure 1. ROC curve Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Dekkerbeurs - Hartstichting

scholarly journals Repetitive Evaluation of Fibrillation Cycle Length Predicts the Effect of Bepridil for Conversion of Long-Lasting Persistent Atrial Fibrillation to Sinus Rhythm

2011 ◽  
Vol 27 (Supplement) ◽  
pp. OP51_4
Author(s):  
Yuya Aoyama ◽  
Shinichi Niwano ◽  
Hiroe Niwano ◽  
Yoshihiro Yumoto ◽  
Akira Sato ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Cycle Length ◽  
Persistent Atrial Fibrillation

scholarly journals Heartbeat Cycle Length Detection by a Ballistocardiographic Sensor in Atrial Fibrillation and Sinus Rhythm

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Matthias Daniel Zink ◽  
Christoph Brüser ◽  
Patrick Winnersbach ◽  
Andreas Napp ◽  
Steffen Leonhardt ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Heart Rate ◽  
Sinus Rhythm ◽  
Quality Index ◽  
Cycle Length ◽  
Heart Rate Monitoring ◽  
Mechanical Vibrations ◽  
Before And After ◽  
Registration Number ◽  
Novel Algorithm

Background.Heart rate monitoring is especially interesting in patients with atrial fibrillation (AF) and is routinely performed by ECG. A ballistocardiography (BCG) foil is an unobtrusive sensor for mechanical vibrations. We tested the correlation of heartbeat cycle length detection by a novel algorithm for a BCG foil to an ECG in AF and sinus rhythm (SR).Methods.In 22 patients we obtained BCG and synchronized ECG recordings before and after cardioversion and examined the correlation between heartbeat characteristics.Results.We analyzed a total of 4317 heartbeats during AF and 2445 during SR with a correlation between ECG and BCG during AF ofr=0.70(95% CI 0.68–0.71,P<0.0001) andr=0.75(95% CI 0.73–0.77,P<0.0001) during SR. By adding a quality index, artifacts could be reduced and the correlation increased for AF to 0.76 (95% CI 0.74–0.77,P<0.0001,n=3468) and for SR to 0.85 (95% CI 0.83–0.86,P<0.0001,n=2176).Conclusion.Heartbeat cycle length measurement by our novel algorithm for BCG foil is feasible during SR and AF, offering new possibilities of unobtrusive heart rate monitoring. This trial is registered with IRB registration number EK205/11. This trial is registered with clinical trials registration numberNCT01779674.

scholarly journals Estimating refractory periods during atrial fibrillation based on electrogram cycle lengths in a heterogeneous simulation setup

2017 ◽  
Vol 3 (2) ◽  
pp. 317-320 ◽  
Author(s):  
Laura Unger ◽  
Tobias Oesterlein ◽  
Gunnar Seemann ◽  
Olaf Dössel ◽  
Peter Spector ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Refractory Period ◽  
Cycle Length ◽  
Spherical Model ◽  
Effective Refractory Period ◽  
Absolute Difference ◽  
Sequential Approach ◽  
Tissue Properties ◽  
Refractory Periods ◽  
Mapping Techniques

AbstractAcquiring adequate mapping data in patients with atrial fibrillation is still one of the main obstacles in the treatment of this atrial arrhythmia. Due to the lack of catheters with both a panoramic field of view and sufficient electrode density for simultaneous mapping, electrophysiologists are forced to fall back on sequential mapping techniques. But, because activation patterns change rapidly during atrial fibrillation, they cannot be mapped sequentially. We propose that mapping tissue properties which are time independent, in contrast, allows a sequential approach. Here, we use the shortest measured electrogram cycle length to estimate the effective refractory period of the underlying tissue in a simulation study. Atrial fibrillation was simulated in a spherical model of the left atrium comprised of regions with varied refractory period. We found that the minimal measured electrogram cycle length correlates with the effective refractory period of the underlying tissue if the regions with distinct refractory properties are large enough and if the absolute difference in effective refractory periods is sufficient. This approach is capable of identifying regions of lowered effective refractory period without the need for cardioversion. Those regions are likely to harbor drivers of atrial fibrillation, which emphasizes the necessity of their localization.

Sign in / Sign up

Export Citation Format

Share Document