Alternans by non-monotonic conduction velocity restitution, bistability and memory
Conduction velocity (CV) restitution is a key property that characterizes any medium supporting traveling waves. It reflects not only the dynamics of the individual constituents but also the coupling mechanism that mediates their interaction. Recent studies have suggested that cardiac tissues, which...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2013-01-01
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| Series: | New Journal of Physics |
| Online Access: | https://doi.org/10.1088/1367-2630/15/1/013046 |
| _version_ | 1827874581987196928 |
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| author | Tae Yun Kim Jin Hee Hong Ryoun Heo Kyoung J Lee |
| author_facet | Tae Yun Kim Jin Hee Hong Ryoun Heo Kyoung J Lee |
| author_sort | Tae Yun Kim |
| collection | DOAJ |
| description | Conduction velocity (CV) restitution is a key property that characterizes any medium supporting traveling waves. It reflects not only the dynamics of the individual constituents but also the coupling mechanism that mediates their interaction. Recent studies have suggested that cardiac tissues, which have a non-monotonic CV-restitution property, can support alternans , a period-2 oscillatory response of periodically paced cardiac tissue. This study finds that single-hump, non-monotonic, CV-restitution curves are a common feature of in vitro cultures of rat cardiac cells. We also find that the Fenton–Karma model, one of the well-established mathematical models of cardiac tissue, supports a very similar non-monotonic CV restitution in a physiologically relevant parameter regime. Surprisingly, the mathematical model as well as the cell cultures support bistability and show cardiac memory that tends to work against the generation of an alternans. Bistability was realized by adopting two different stimulation protocols, ‘S1S2’, which produces a period-1 wave train, and ‘alternans-pacing’, which favors a concordant alternans. Thus, we conclude that the single-hump non-monotonicity in the CV-restitution curve is not sufficient to guarantee a cardiac alternans, since cardiac memory interferes and the way the system is paced matters. |
| first_indexed | 2024-03-12T16:53:56Z |
| format | Article |
| id | doaj.art-b91a07cb7c6d4435a2a93f432ba84af8 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:53:56Z |
| publishDate | 2013-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-b91a07cb7c6d4435a2a93f432ba84af82023-08-08T11:03:32ZengIOP PublishingNew Journal of Physics1367-26302013-01-0115101304610.1088/1367-2630/15/1/013046Alternans by non-monotonic conduction velocity restitution, bistability and memoryTae Yun Kim0Jin Hee Hong1Ryoun Heo2Kyoung J Lee3Department of Physics, Korea University , Anam-dong 5-1, Sungbuk-gu, Seoul, KoreaDepartment of Physics, Korea University , Anam-dong 5-1, Sungbuk-gu, Seoul, KoreaDepartment of Physics, Korea University , Anam-dong 5-1, Sungbuk-gu, Seoul, KoreaDepartment of Physics, Korea University , Anam-dong 5-1, Sungbuk-gu, Seoul, KoreaConduction velocity (CV) restitution is a key property that characterizes any medium supporting traveling waves. It reflects not only the dynamics of the individual constituents but also the coupling mechanism that mediates their interaction. Recent studies have suggested that cardiac tissues, which have a non-monotonic CV-restitution property, can support alternans , a period-2 oscillatory response of periodically paced cardiac tissue. This study finds that single-hump, non-monotonic, CV-restitution curves are a common feature of in vitro cultures of rat cardiac cells. We also find that the Fenton–Karma model, one of the well-established mathematical models of cardiac tissue, supports a very similar non-monotonic CV restitution in a physiologically relevant parameter regime. Surprisingly, the mathematical model as well as the cell cultures support bistability and show cardiac memory that tends to work against the generation of an alternans. Bistability was realized by adopting two different stimulation protocols, ‘S1S2’, which produces a period-1 wave train, and ‘alternans-pacing’, which favors a concordant alternans. Thus, we conclude that the single-hump non-monotonicity in the CV-restitution curve is not sufficient to guarantee a cardiac alternans, since cardiac memory interferes and the way the system is paced matters.https://doi.org/10.1088/1367-2630/15/1/013046 |
| spellingShingle | Tae Yun Kim Jin Hee Hong Ryoun Heo Kyoung J Lee Alternans by non-monotonic conduction velocity restitution, bistability and memory New Journal of Physics |
| title | Alternans by non-monotonic conduction velocity restitution, bistability and memory |
| title_full | Alternans by non-monotonic conduction velocity restitution, bistability and memory |
| title_fullStr | Alternans by non-monotonic conduction velocity restitution, bistability and memory |
| title_full_unstemmed | Alternans by non-monotonic conduction velocity restitution, bistability and memory |
| title_short | Alternans by non-monotonic conduction velocity restitution, bistability and memory |
| title_sort | alternans by non monotonic conduction velocity restitution bistability and memory |
| url | https://doi.org/10.1088/1367-2630/15/1/013046 |
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