@article{ISI:000343239800010,
 abstract = {Wave propagation around various geometric expansions, structures, and
obstacles in cardiac tissue may result in the formation of
unidirectional block of wave propagation and the onset of reentrant
arrhythmias in the heart. Therefore, we investigated the conditions
under which reentrant spiral waves can be generated by high-frequency
stimulation at sharp-edged obstacles in the ten
Tusscher-Noble-Noble-Panfilov (TNNP) ionic model for human cardiac
tissue. We show that, in a large range of parameters that account for
the conductance of major inward and outward ionic currents of the model
[fast inward Na+ current (INa), L-type slow inward Ca2+ current
(I-CaL), slow delayed-rectifier current (I-Ks), rapid delayed-rectifier
current (I-Kr), inward rectifier K+ current (I-K1)], the critical period
necessary for spiral formation is close to the period of a spiral wave
rotating in the same tissue. We also show that there is a minimal size
of the obstacle for which formation of spirals is possible; this size is
similar to 2.5 cm and decreases with a decrease in the excitability of
cardiac tissue. We show that other factors, such as the obstacle
thickness and direction of wave propagation in relation to the obstacle,
are of secondary importance and affect the conditions for spiral wave
initiation only slightly. We also perform studies for obstacle shapes
derived from experimental measurements of infarction scars and show that
the formation of spiral waves there is facilitated by tissue remodeling
around it. Overall, we demonstrate that the formation of reentrant
sources around inexcitable obstacles is a potential mechanism for the
onset of cardiac arrhythmias in the presence of a fast heart rate.},
 author = {Majumder, Rupamanjari and Pandit, Rahul and Panfilov, A. V.},
 doi = {10.1152/ajpheart.00593.2013},
 eissn = {1522-1539},
 issn = {0363-6135},
 journal = {AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY},
 month = {OCT 1},
 number = {7},
 orcid-numbers = {Panfilov, Alexander/0000-0003-2643-642X},
 pages = {H1024-H1035},
 researcherid-numbers = {Panfilov, Alexander/G-8459-2016},
 times-cited = {6},
 title = {Turbulent electrical activity at sharp-edged inexcitable obstacles in a
model for human cardiac tissue},
 unique-id = {ISI:000343239800010},
 volume = {307},
 year = {2014}
}