PMID- 19964069
OWN - NLM
STAT- MEDLINE
DCOM- 20100422
LR  - 20200928
IS  - 2375-7477 (Print)
IS  - 2375-7477 (Linking)
VI  - 2009
DP  - 2009
TI  - A computer study of the effects of branching dimension on safety factor 
      distribution and propagation in a cardiac conduction network.
PG  - 3278-81
LID - 10.1109/IEMBS.2009.5333514 [doi]
AB  - Branching conduction networks are responsible for coordinated distribution of 
      activation throughout the heart, but the effects of branching geometry on the 
      efficiency of distribution and the safety of propagation remain unclear. We have 
      developed a simplified computer model to investigate this issue in a systemic 
      fashion. A simplified 2D model that reproduces key features of the right atrial 
      pectinate muscle network has been developed. This consists of a large main strand 
      that gives rise to regularly spaced perpendicular branches. Safety factor (SF) 
      and activation time (AT) within the network are estimated for a range of 
      different branch dimensions. The SF is reduced as branch dimension is increased 
      due to the larger current load and is least at the proximal edge of the junction 
      between the main strand and branches. On the other hand, activation efficiency 
      depends on appropriate balance between the load imposed by branching and source 
      which they subsequently provide. With repeated stimulation at progressively 
      decreasing coupling intervals, the SF and conduction fall within the network, but 
      the locations of block varied with branching dimension, again reflecting spatial 
      variation in the balance between current source and current load. We hypothesize 
      that the observed geometry of the branching network optimizes distribution 
      efficiency and propagation safety.
FAU - Zhao, Jichao
AU  - Zhao J
AD  - Bioengineering Institute, The University of Auckland, 1142, New Zealand. 
      j.zhao@auckland.ac.nz
FAU - Smaill, Bruce H
AU  - Smaill BH
FAU - Pullan, Andrew J
AU  - Pullan AJ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Annu Int Conf IEEE Eng Med Biol Soc
JT  - Annual International Conference of the IEEE Engineering in Medicine and Biology 
      Society. IEEE Engineering in Medicine and Biology Society. Annual International 
      Conference
JID - 101763872
SB  - IM
MH  - Animals
MH  - Biophysics/methods
MH  - Cardiovascular Physiological Phenomena
MH  - Computer Simulation
MH  - Heart/*anatomy & histology/physiology
MH  - Heart Atria/anatomy & histology
MH  - Heart Conduction System/metabolism/*physiology
MH  - Models, Cardiovascular
MH  - Models, Theoretical
MH  - Myocardial Contraction
MH  - Myocardium/metabolism
MH  - Software
MH  - Swine
EDAT- 2009/12/08 06:00
MHDA- 2010/04/23 06:00
CRDT- 2009/12/08 06:00
PHST- 2009/12/08 06:00 [entrez]
PHST- 2009/12/08 06:00 [pubmed]
PHST- 2010/04/23 06:00 [medline]
AID - 10.1109/IEMBS.2009.5333514 [doi]
PST - ppublish
SO  - Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:3278-81. doi: 
      10.1109/IEMBS.2009.5333514.