Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block
Background: Cardiac resynchronization therapy is an effective device therapy for heart failure patients with conduction block. However, a problem with this invasive technique is the nearly 30% of non-responders. A number of studies have reported a functional line of block of cardiac excitation propa...
Main Authors: | , , , , , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Frontiers Media S.A.
2018-02-01
|
Series: | Frontiers in Physiology |
Subjects: | |
Online Access: | http://journal.frontiersin.org/article/10.3389/fphys.2018.00056/full |
id |
doaj-8e569f9fd2924833bd8f77620d2ace68 |
---|---|
record_format |
Article |
spelling |
doaj-8e569f9fd2924833bd8f77620d2ace682020-11-24T23:12:18ZengFrontiers Media S.A.Frontiers in Physiology1664-042X2018-02-01910.3389/fphys.2018.00056326229Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch BlockJun-ichi Okada0Takumi Washio1Machiko Nakagawa2Masahiro Watanabe3Yoshimasa Kadooka4Taro Kariya5Hiroshi Yamashita6Yoko Yamada7Shin-ichi Momomura8Ryozo Nagai9Toshiaki Hisada10Seiryo Sugiura11Department of Human and Engineered Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, JapanDepartment of Human and Engineered Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, JapanHealthcare System Unit, Fujitsu Ltd., Tokyo, JapanHealthcare System Unit, Fujitsu Ltd., Tokyo, JapanHealthcare System Unit, Fujitsu Ltd., Tokyo, JapanDepartment of Cardiovascular Medicine, School of Medicine, The University of Tokyo, Tokyo, JapanDepartment of Cardiovascular Medicine, School of Medicine, The University of Tokyo, Tokyo, JapanDepartment of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, Saitama, JapanDepartment of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, Saitama, JapanDepartment of Cardiovascular Medicine, School of Medicine, The University of Tokyo, Tokyo, JapanDepartment of Human and Engineered Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, JapanDepartment of Human and Engineered Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, JapanBackground: Cardiac resynchronization therapy is an effective device therapy for heart failure patients with conduction block. However, a problem with this invasive technique is the nearly 30% of non-responders. A number of studies have reported a functional line of block of cardiac excitation propagation in responders. However, this can only be detected using non-contact endocardial mapping. Further, although the line of block is considered a sign of responders to therapy, the mechanism remains unclear.Methods: Herein, we created two patient-specific heart models with conduction block and simulated the propagation of excitation based on a cellmodel of electrophysiology. In one model with a relatively narrow QRS width (176 ms), we modeled the Purkinje network using a thin endocardial layer with rapid conduction. To reproduce a wider QRS complex (200 ms) in the second model, we eliminated the Purkinje network, and we simulated the endocardial mapping by solving the inverse problem according to the actual mapping system.Results: We successfully observed the line of block using non-contact mapping in the model without the rapid propagation of excitation through the Purkinje network, although the excitation in the wall propagated smoothly. This model of slow conduction also reproduced the characteristic properties of the line of block, including dense isochronal lines and fractionated local electrocardiograms. Further, simulation of ventricular pacing from the lateral wall shifted the location of the line of block. By contrast, in the model with the Purkinje network, propagation of excitation in the endocardial map faithfully followed the actual propagation in the wall, without showing the line of block. Finally, switching the mode of propagation between the two models completely reversed these findings.Conclusions: Our simulation data suggest that the absence of rapid propagation of excitation through the Purkinje network is the major cause of the functional line of block recorded by non-contact endocardial mapping. The line of block can be used to identify responders as these patients loose rapid propagation through the Purkinje network.http://journal.frontiersin.org/article/10.3389/fphys.2018.00056/fullmulti-scale simulationconduction blocknon-contact mappingline of blockPurkinje networkelectrophysiology |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Jun-ichi Okada Takumi Washio Machiko Nakagawa Masahiro Watanabe Yoshimasa Kadooka Taro Kariya Hiroshi Yamashita Yoko Yamada Shin-ichi Momomura Ryozo Nagai Toshiaki Hisada Seiryo Sugiura |
spellingShingle |
Jun-ichi Okada Takumi Washio Machiko Nakagawa Masahiro Watanabe Yoshimasa Kadooka Taro Kariya Hiroshi Yamashita Yoko Yamada Shin-ichi Momomura Ryozo Nagai Toshiaki Hisada Seiryo Sugiura Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block Frontiers in Physiology multi-scale simulation conduction block non-contact mapping line of block Purkinje network electrophysiology |
author_facet |
Jun-ichi Okada Takumi Washio Machiko Nakagawa Masahiro Watanabe Yoshimasa Kadooka Taro Kariya Hiroshi Yamashita Yoko Yamada Shin-ichi Momomura Ryozo Nagai Toshiaki Hisada Seiryo Sugiura |
author_sort |
Jun-ichi Okada |
title |
Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block |
title_short |
Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block |
title_full |
Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block |
title_fullStr |
Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block |
title_full_unstemmed |
Absence of Rapid Propagation through the Purkinje Network as a Potential Cause of Line Block in the Human Heart with Left Bundle Branch Block |
title_sort |
absence of rapid propagation through the purkinje network as a potential cause of line block in the human heart with left bundle branch block |
publisher |
Frontiers Media S.A. |
series |
Frontiers in Physiology |
issn |
1664-042X |
publishDate |
2018-02-01 |
description |
Background: Cardiac resynchronization therapy is an effective device therapy for heart failure patients with conduction block. However, a problem with this invasive technique is the nearly 30% of non-responders. A number of studies have reported a functional line of block of cardiac excitation propagation in responders. However, this can only be detected using non-contact endocardial mapping. Further, although the line of block is considered a sign of responders to therapy, the mechanism remains unclear.Methods: Herein, we created two patient-specific heart models with conduction block and simulated the propagation of excitation based on a cellmodel of electrophysiology. In one model with a relatively narrow QRS width (176 ms), we modeled the Purkinje network using a thin endocardial layer with rapid conduction. To reproduce a wider QRS complex (200 ms) in the second model, we eliminated the Purkinje network, and we simulated the endocardial mapping by solving the inverse problem according to the actual mapping system.Results: We successfully observed the line of block using non-contact mapping in the model without the rapid propagation of excitation through the Purkinje network, although the excitation in the wall propagated smoothly. This model of slow conduction also reproduced the characteristic properties of the line of block, including dense isochronal lines and fractionated local electrocardiograms. Further, simulation of ventricular pacing from the lateral wall shifted the location of the line of block. By contrast, in the model with the Purkinje network, propagation of excitation in the endocardial map faithfully followed the actual propagation in the wall, without showing the line of block. Finally, switching the mode of propagation between the two models completely reversed these findings.Conclusions: Our simulation data suggest that the absence of rapid propagation of excitation through the Purkinje network is the major cause of the functional line of block recorded by non-contact endocardial mapping. The line of block can be used to identify responders as these patients loose rapid propagation through the Purkinje network. |
topic |
multi-scale simulation conduction block non-contact mapping line of block Purkinje network electrophysiology |
url |
http://journal.frontiersin.org/article/10.3389/fphys.2018.00056/full |
work_keys_str_mv |
AT junichiokada absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT takumiwashio absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT machikonakagawa absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT masahirowatanabe absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT yoshimasakadooka absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT tarokariya absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT hiroshiyamashita absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT yokoyamada absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT shinichimomomura absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT ryozonagai absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT toshiakihisada absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock AT seiryosugiura absenceofrapidpropagationthroughthepurkinjenetworkasapotentialcauseoflineblockinthehumanheartwithleftbundlebranchblock |
_version_ |
1725601487006990336 |