Abstract：
:Point cathodal stimulation of cardiac tissue was shown previously to produce both a dog-bone shaped virtual cathode transverse to the muscle fibers and two longitudinal virtual anodes. We hypothesize that virtual anodes can cause a region of delayed activation, separating two regions of early activation caused by the virtual cathode. Using a high-density electrode array in 42 superfused epicardial slices from 14 canine left ventricles, we observed regions of early and delayed activation and different pathways of retrograde propagation corresponding to the earlier patterns. Retrograde propagation was seen from the transversely located early activation area through areas of delayed activation toward the cathode, and from the early activation area toward the cathode directly. These pathways caused a wide dispersion in the direction of retrograde propagation (2 degrees +/- 31 degrees, n = 179, relative to the fast axis of threshold activation; radial velocity: 0.5 +/- 0.2 m/s, n = 95, in 12 slices from 8 hearts with stimuli of 330 micros, 0.8-30 mA). Delayed activations were observed 0 degrees +/- 6 degrees (n = 32) from the axis in 23 maps (at differing stimulation strengths) recorded in 13 slices from 10 hearts. We conclude that point cathodal stimulation induce delayed activation along the fiber axis and retrograde propagation both along and transverse to the axis.
journal_name
Ann Biomed Engjournal_title
Annals of biomedical engineeringauthors
Wu J,Roden DM,Wikswo JP Jrdoi
10.1114/1.1326029subject
Has Abstractpub_date
2000-11-01 00:00:00pages
1318-25issue
11eissn
0090-6964issn
1573-9686journal_volume
28pub_type
杂志文章abstract：:Intramuscular pressure (IMP) shows promise for estimating individual muscle tension in vivo. However, previous pressure measurements show high variability during isometric contraction and poor correlation with tension during dynamic contraction. We hypothesized that enhanced sensor anchoring/orientation would improve ...
journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
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更新日期：2017-11-01 00:00:00
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章,评审
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-010-0155-7
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journal_title：Annals of biomedical engineering
pub_type： 临床试验,杂志文章
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
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journal_title：Annals of biomedical engineering
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doi：10.1007/s10439-011-0329-y
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-008-9555-3
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
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doi：10.1007/s10439-010-0023-5
更新日期：2010-08-01 00:00:00
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-018-2073-z
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journal_title：Annals of biomedical engineering
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doi：10.1007/s10439-018-02113-z
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journal_title：Annals of biomedical engineering
pub_type： 临床试验,杂志文章
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
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journal_title：Annals of biomedical engineering
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
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journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-005-9050-z
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journal_title：Annals of biomedical engineering
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更新日期：1990-01-01 00:00:00
