scholarly journals B-PO01-016 INDUCIBILITY OF ATRIAL FIBRILLATION IS RELATED TO CONDUCTION ABNORMALITIES AT BACHMANN’S BUNDLE

Heart Rhythm ◽  
2021 ◽  
Vol 18 (8) ◽  
pp. S57
Author(s):  
Lianne N. van Staveren ◽  
Willemijn F.B. van der Does ◽  
Annejet Heida ◽  
Yannick J.H.J. Taverne ◽  
Natasja M.S. De Groot
Keyword(s):  
Atrial Fibrillation ◽  
Conduction Abnormalities ◽  
Bachmann’S Bundle

RELATIVE CONTRIBUTIONS OF FIBROSIS AND CONNEXIN CHANGES TOTHE ATRIAL FIBRILLATION SUBSTRATE DURING THE DEVELOPMENT AND REVERSAL OF CONGESTIVEHEART FAILURE

2008 ◽  
Vol 31 (4) ◽  
pp. 5
Author(s):  
Brett Burstein ◽  
Kunihiro Nishida ◽  
Philippe Comtois ◽  
Louis Villenuve ◽  
Yung-Hsin Yeh ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Potential Model ◽  
Diastolic Pressure ◽  
Recovery Period ◽  
Left Ventricular ◽  
Muscle Bundle ◽  
Protein Ratio ◽  
Conduction Disturbances ◽  
Conduction Abnormalities ◽  
Mrna And Protein Expression

Background: Connexin alterations occur in various atrial fibrillation (AF) paradigms, but their functional significance remains unclear. No data are available regarding the effects of CHF on atrial connexin expression and phosphorylation. We therefore analyzed connexin changes and their contribution to the AF substrate during the development and reversal ofCHF. Methods and Results: Dogs were allocated to three groups: CHF induced by 2-week ventricular tachypacing (CHF, n=15); CHF dogs allowed to recover for 4 weeks after 2-week tachypacing (REC, n=15) and non-paced shams (CTL, n=11). Left ventricular end-diastolic pressure increased with CHF (14.5±1.0*** vs.3.7±0.7, ***P < 0.001 vs. CTL) and normalized upon CHF recovery (5.1±1.0^†††, ^††† P < 0.001 vs. CHF). Real-time PCR and Western-blot analyses revealed connexin43 (Cx43) and connexin40 (Cx40) mRNA and protein expression to be unchanged by CHF and REC. However, CHF caused Cx43 dephosphorylation(by ~73%***) and increased Cx40/Cx43 protein ratio (by ~35%***), with both alterations completely reversing in REC. Immunofluorescent confocal microscopy confirmed connexin protein trends, with a reduction in phosphorylated Cx43 (by ~68%*** in CHF) that returned to control in REC. CHF caused conduction abnormalities (phasedelay-range and heterogeneity index, both P < 0.01) and burst pacing-induced AF prolongation (CTL 22±7s, CHF 1100±171s***, REC 884±220s***) which persisted in the recovery period, along with residual fibrosis (CTL 3.6±0.7%, CHF 14.7±1.5%***, REC13.3±2.3%***). Fibrosis physically interrupted muscle bundle continuity and anionically-based action potential model of canine atrium showed that fibrosiswas able to account for the observed conduction abnormalities. Conclusions: CHF causes connexin-dephosphorylation and Cx40/Cx43ratio increases. With CHF reversal, atrial connexin alterations recover completely, but tissue fibrosis, conduction abnormalities and a substrate forAF remain with fibrosis accounting for conduction abnormalities. Thus, althougha trial connexin changes occur with CHF, they are not essential for conduction disturbances and AF promotion, which appear rather to be related primarily tofibrotic interruption of muscle-bundle continuity.

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 &lt;0.05NA= not available

scholarly journals Effect of bachmann's bundle pacing on atrial fibrillation: Electrophysiologic assessment

2004 ◽  
Vol 27 (1) ◽  
pp. 50-53 ◽  
Author(s):  
A. John Camm ◽  
Koichiro Kumagai ◽  
Hideaki Tojo ◽  
Tomoo Yasuda ◽  
Keijiro Saku
Keyword(s):  
Atrial Fibrillation ◽  
Bachmann’S Bundle

scholarly journals Rates of Cardiac Rhythm Abnormalities in Patients with CKD and Diabetes

2019 ◽  
Vol 14 (4) ◽  
pp. 549-556 ◽  
Author(s):  
Nazem Akoum ◽  
Leila R. Zelnick ◽  
Ian H. de Boer ◽  
Irl B. Hirsch ◽  
Dace Trence ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cardiac Arrhythmias ◽  
Ventricular Arrhythmias ◽  
Cardiac Rhythm ◽  
Cardiac Monitoring ◽  
Premature Ventricular Contractions ◽  
Mortality And Morbidity ◽  
Conduction Abnormalities ◽  
Patients With Diabetes ◽  
New Diagnosis

Background and objectivesCardiac arrhythmias increase mortality and morbidity in CKD. We evaluated the rates of subclinical arrhythmias in a population with type 2 diabetes and patients with moderate to severe CKD who were not on dialysis.Design, setting, participants & measurementsThis is a prospective observational study, using continuous ambulatory cardiac monitors to determine the rate of atrial and ventricular arrhythmias, as well as conduction abnormalities in this group.ResultsA total of 38 patients (34% women), with mean eGFR of 38±13 ml/min per 1.73 m2, underwent ambulatory cardiac monitoring for 11.2±3.9 days. The overall mean rate of any cardiac arrhythmia was 88.8 (95% confidence interval [95% CI], 27.1 to 184.6) episodes per person-year (PY). A history of cardiovascular disease was associated with a higher rate of detected arrhythmia (rate ratio, 5.87; 95% CI, 1.37 to 25.21; P<0.001). The most common arrhythmia was atrial fibrillation, which was observed in two participants with known atrial fibrillation and was a new diagnosis in four patients (11%), none of whom experienced symptoms. Overall, atrial fibrillation episodes occurred at a rate of 37.6 (95% CI, 2.4 to 112.3) per PY. Conduction abnormalities were found in eight patients (21%), a rate of 26.5 (95% CI, 4.2 to 65.5) per PY. Rates of ventricular arrhythmias were low (14.5 per PY; 95% CI, 4.3 to 32.0) and driven by premature ventricular contractions.ConclusionsCardiac rhythm abnormalities are common in patients with diabetes with moderate to severe CKD not requiring dialysis. Rates of atrial fibrillation are high and episodes are asymptomatic. Future studies are needed to determine the role of screening and upstream therapy of cardiac arrhythmias in this group.

Abstract 17255: Premature Atrial Stimulation Reveals Increased Conduction Slowing and Block in Cardiac Surgery Patients That Develop Postoperative Atrial Fibrillation

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Muhammad S Khan ◽  
Vikas Sharma ◽  
Ravi Ranjan ◽  
Jason P Glotzbach ◽  
Craig Selzman ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cardiac Surgery ◽  
Pulmonary Veins ◽  
Conduction Block ◽  
Postoperative Atrial Fibrillation ◽  
Conduction Delay ◽  
Epicardial Mapping ◽  
Conduction Abnormalities ◽  
History Of ◽  
Atrial Stimulation

Introduction: Postoperative atrial fibrillation (POAF) is a common cardiac surgery complication that is highly associated with increased morbidity and mortality. The relation of presurgical left atrial (LA) conduction abnormalities and POAF during intraoperative premature atrial stimulation (S1S2) pacing is investigated and reported. Hypothesis: Intraoperative premature atrial stimulation reveals increased areas of slowed or blocked conduction in patients that develop POAF. Methods: High-density intraoperative epicardial mapping was conducted in 20 cardiac surgery patients with no history of preoperative atrial fibrillation (AF) both in sinus rhythm (SR) and during S1S2 pacing. A flexible array comprised of 240 electrodes was placed on the posterior LA wall in between the pulmonary veins. For each patient, the area of conduction block (CB), conduction delay (CD) and combined conduction delay and block (CDCB) for conduction velocity <0.1 m/s, 0.1 - 0.2 m/s and <0.2 m/s, respectively were quantified. Results: In 20 patients, 6 (30%) developed POAF. As shown in the Figure, conduction maps revealed the presence of significantly higher areas of CD (13.2±6.6% vs. 6.1±4.2%, p=0.03) and CDCB (17.5±8.7% vs. 7.4±6.4%, p=0.03), and a trend toward larger CB (4.2±3.8% vs. 1.3±2.9%, p=0.09) in patients that developed POAF for premature atrial beat S2 compared to patients that remained in SR after cardiac surgery. S1 paced beats and SR did not show significant differences in abnormal conduction percentages between patients with and without POAF. Conclusions: Premature atrial stimulation accentuates conduction abnormalities in cardiac surgery patients that develop POAF, revealing a pre-surgical substrate that may indicate greater risk for post-surgical atrial arrhythmias.

Does Bachmann's bundle pacing prevent atrial fibrillation in myotonic dystrophy type 1 patients? A 12 months follow-up study

EP Europace ◽  
2010 ◽  
Vol 12 (9) ◽  
pp. 1219-1223 ◽  
Author(s):  
G. Nigro ◽  
V. Russo ◽  
L. Politano ◽  
N. Della Cioppa ◽  
A. Rago ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Myotonic Dystrophy ◽  
Myotonic Dystrophy Type 1 ◽  
Myotonic Dystrophy Type ◽  
Follow Up Study ◽  
Bachmann’S Bundle

The role of bachmann’s bundle during chronic atrial fibrillation in patients with mitral valve disease

Heart Rhythm ◽  
2005 ◽  
Vol 2 (5) ◽  
pp. S269
Author(s):  
Natasja M. De Groot ◽  
Pieter Voigt ◽  
Jerry Braun ◽  
Martin J. Schalij ◽  
Maurits Allessie
Keyword(s):  
Atrial Fibrillation ◽  
Mitral Valve ◽  
Mitral Valve Disease ◽  
Chronic Atrial Fibrillation ◽  
Valve Disease ◽  
Bachmann’S Bundle

scholarly journals Conduction Abnormalities: Types, Associated Factors and their Effect on Clinical Outcomes of Patients Admitted to the Coronary Care Unit at King Abdulaziz University Hospital

2019 ◽  
Vol 9 (1) ◽  
pp. 37-43
Author(s):  
Nahla K. Ibrahim ◽  
Kamal W. Alghalayini ◽  
Asmaa A. Milyani ◽  
Afnan M. Neyas ◽  
Rahaf F. Alturkistani ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Hospital Stay ◽  
Coronary Care Unit ◽  
University Hospital ◽  
Bundle Branch Block ◽  
Conduction Abnormality ◽  
Conduction Abnormalities ◽  
King Abdulaziz University ◽  
Coronary Care ◽  
Time Of Admission

Background: Since conduction abnormalities represent a major cause of sudden death and cardiovascular complications, with a high incidence of increased length of hospital stay, risk of disabilities and healthcare costs, the aim was to discern the influence of conduction abnormalities at the time of admission on the clinical outcomes of patients admitted at the Coronary Care Unit in King Abdulaziz University Hospital. Method: The study adopted a retrospective-record review, episode-based design for a period of 2 years. All patients with sustained conduction abnormalities at the time of admission that had either self-terminated or required intervention were recruited. Statistical analysis was conducted by SPSS. Results:  A total of 1763 admissions occurred during the study period, conduction abnormalities represented 11.5% of all these cases. The most common types were left bundle branch block and atrial fibrillation. Types that were significantly associated with the length of stay were atrial fibrillation (p = 0.045), ventricular tachycardia (p = 0.020), and ventricular fibrillation (p = 0.007) and complete heart block (p = 0.004). Right bundle branch block was the only conduction abnormality that was significantly associated with higher mortality (p = 0.011). Conclusion:  Patients with right bundle branch block need close monitoring and optimal care to reduce risks of increased hospital stay and death. Further, it is imperative that attention should be directed in general to all patients admitted to the Coronary Care Unit with any kind of conduction abnormality in order to attempt to reduce their stay.

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