Tags

Type your tag names separated by a space and hit enter

Difference between electrical remodelling after pulmonary veins and right atrium appendage pacing.
Europace. 2007 Aug; 9(8):608-12.E

Abstract

OBJECTIVE

Pulmonary veins (PVs) are important sources of paroxysmal atrial fibrillation (AF). Rapid atrial pacing changes atrial electrophysiology, and facilitates the induction and maintenance of AF. The purpose of our study was to evaluate the changes in atrial effective refractory period (AERP) proprieties and in ionic currents in PVs myocytes from dogs subjected to rapid atrial pacing in PVs and right atrial appendage (RAA) and to relate these changes to the ability to induce AF.

METHODS

Twelve mongrel dogs in normal sinus rhythm were paced from the superior left PVs or RAA at 500 bpm for 4 h. Electrophysiological studies were conducted to determine the changes in AERP, dispersion, and rhythm. Ionic currents were evaluated using patch clamp technique in single PVs myocytes in sham-operated dogs, and the results were compared with those from PVs and RAA pacing groups.

RESULTS

The presence of rapid atrial pacing was associated with a marked shortening in AERP in both PVs and RAA pacing group with a marked increase in AERP dispersion in PVs pacing. Both L-type calcium current (I(Ca,L)) and the transient outward current (I(to)) were reduced in both groups with an increased significance in PVs pacing group. The density of I(Ca,L) was decreased significantly from (-6.03 +/- 0.63) pA/pF in the control group to (-3.21 +/- 0.34) pA/pF in the PVs pacing group and (-4.75 +/- 0.41) pA/pF in the RAA pacing group (n = 6, P < 0.05), whereas the density of I(to) was decreased significantly from (8.45 +/- 0.71) pA/pF in the control group to (5.21 +/- 0.763) pA/pF in the PVs pacing group and (6.84 +/- 0.69) pA/pF in the RAA pacing group (n = 6, P < 0.05).

CONCLUSION

Our findings provide likely ionic mechanisms of shortened repolarization in induced atrial tachycardia with a decrease in I(Ca,L) and I(to) densities, which is the likely mechanism for a decrease in action potential duration rate adaptation in the canine rapid pacing model more pronounced in the PVs pacing group underlying the crucial role of PVs in initiating AF.

Links

Publisher Full Text
Aggregator Full Text

Authors+Show Affiliations

Hafid KA
Department of Cardiology, Renmin Hospital of Wuhan University, Jiefang Road 238, Wuhan 430060, People's Republic of China.
Xin HC
No affiliation info available
Xi W
No affiliation info available
Yan ZQ
No affiliation info available
Bo Y
No affiliation info available

MeSH

Action PotentialsAnimalsAtrial FibrillationBiological ClocksCardiac Pacing, ArtificialCells, CulturedDogsHeart AtriaHeart Conduction SystemMyocytes, CardiacPulmonary Veins

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

17630393

Citation

Hafid, Kebbati A., et al. "Difference Between Electrical Remodelling After Pulmonary Veins and Right Atrium Appendage Pacing." Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups On Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology, vol. 9, no. 8, 2007, pp. 608-12.
Hafid KA, Xin HC, Xi W, et al. Difference between electrical remodelling after pulmonary veins and right atrium appendage pacing. Europace. 2007;9(8):608-12.
Hafid, K. A., Xin, H. C., Xi, W., Yan, Z. Q., & Bo, Y. (2007). Difference between electrical remodelling after pulmonary veins and right atrium appendage pacing. Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups On Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology, 9(8), 608-12.
Hafid KA, et al. Difference Between Electrical Remodelling After Pulmonary Veins and Right Atrium Appendage Pacing. Europace. 2007;9(8):608-12. PubMed PMID: 17630393.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Difference between electrical remodelling after pulmonary veins and right atrium appendage pacing. AU - Hafid,Kebbati A, AU - Xin,Huang Cong, AU - Xi,Wang, AU - Yan,Zhao Qing, AU - Bo,Yang, Y1 - 2007/07/13/ PY - 2007/7/17/pubmed PY - 2007/12/14/medline PY - 2007/7/17/entrez SP - 608 EP - 12 JF - Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology JO - Europace VL - 9 IS - 8 N2 - OBJECTIVE: Pulmonary veins (PVs) are important sources of paroxysmal atrial fibrillation (AF). Rapid atrial pacing changes atrial electrophysiology, and facilitates the induction and maintenance of AF. The purpose of our study was to evaluate the changes in atrial effective refractory period (AERP) proprieties and in ionic currents in PVs myocytes from dogs subjected to rapid atrial pacing in PVs and right atrial appendage (RAA) and to relate these changes to the ability to induce AF. METHODS: Twelve mongrel dogs in normal sinus rhythm were paced from the superior left PVs or RAA at 500 bpm for 4 h. Electrophysiological studies were conducted to determine the changes in AERP, dispersion, and rhythm. Ionic currents were evaluated using patch clamp technique in single PVs myocytes in sham-operated dogs, and the results were compared with those from PVs and RAA pacing groups. RESULTS: The presence of rapid atrial pacing was associated with a marked shortening in AERP in both PVs and RAA pacing group with a marked increase in AERP dispersion in PVs pacing. Both L-type calcium current (I(Ca,L)) and the transient outward current (I(to)) were reduced in both groups with an increased significance in PVs pacing group. The density of I(Ca,L) was decreased significantly from (-6.03 +/- 0.63) pA/pF in the control group to (-3.21 +/- 0.34) pA/pF in the PVs pacing group and (-4.75 +/- 0.41) pA/pF in the RAA pacing group (n = 6, P < 0.05), whereas the density of I(to) was decreased significantly from (8.45 +/- 0.71) pA/pF in the control group to (5.21 +/- 0.763) pA/pF in the PVs pacing group and (6.84 +/- 0.69) pA/pF in the RAA pacing group (n = 6, P < 0.05). CONCLUSION: Our findings provide likely ionic mechanisms of shortened repolarization in induced atrial tachycardia with a decrease in I(Ca,L) and I(to) densities, which is the likely mechanism for a decrease in action potential duration rate adaptation in the canine rapid pacing model more pronounced in the PVs pacing group underlying the crucial role of PVs in initiating AF. SN - 1099-5129 UR - https://www.unboundmedicine.com/medline/citation/17630393/Difference_between_electrical_remodelling_after_pulmonary_veins_and_right_atrium_appendage_pacing_ L2 - https://academic.oup.com/europace/article-lookup/doi/10.1093/europace/eum108 DB - PRIME DP - Unbound Medicine ER -