Journal article
Dual-dye optical mapping after myocardial infarction: does the site of ventricular stimulation alter the properties of electrical propagation?
Journal of cardiovascular electrophysiology, Vol.19(2), pp.197-202
02/2008
DOI: 10.1111/j.1540-8167.2007.00998.x
PMID: 17971142
Abstract
Myocardial infarction (MI) disrupts electrical conduction in affected ventricular areas. We investigated the effect of MI on the regional voltage and calcium (Ca) signals and their propagation properties, with special attention to the effect of the site of ventricular pacing on these properties.
New Zealand White rabbits were divided into four study groups: sham-operated (C, n = 6), MI with no pacing (MI, n = 7), MI with right ventricular pacing (MI + RV, n = 6), and MI with BIV pacing (MI + BIV, n = 7). At 4 weeks, hearts were excised, perfused, and optically mapped. As previously shown, systolic and diastolic dilation of the LV were prevented by BIV pacing, as was the reduction in LV fractional shortening.
Four weeks after MI, optical mapping revealed markedly reduced action potential amplitudes and conduction velocities (CV) in MI zones, and these increased gradually in the border zone and normal myocardial areas. Also, Ca transients were absent in the infarcted areas and increased gradually 3-5 mm from the border of the normal zone. Neither BIV nor RV pacing affected these findings in any of the MI, border, or normal zones.
MI has profound effects on the regional electrical and Ca signals and on their propagation properties in this rabbit model. The absence of differences in these parameters by study group suggests that altering the properties of myocardial electrical conduction and Ca signaling are unlikely mechanisms by which BIV pacing confers its benefits. Further studies into the regional, cellular, and molecular benefits of BIV pacing are therefore warranted.
Details
- Title: Subtitle
- Dual-dye optical mapping after myocardial infarction: does the site of ventricular stimulation alter the properties of electrical propagation?
- Creators
- Samir Saba - Cardiovascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA. sabas@upmc.eduMichael A MathierHaider MehdiTong LiuBum-Rak ChoiBarry LondonGuy Salama
- Resource Type
- Journal article
- Publication Details
- Journal of cardiovascular electrophysiology, Vol.19(2), pp.197-202
- Publisher
- United States
- DOI
- 10.1111/j.1540-8167.2007.00998.x
- PMID
- 17971142
- ISSN
- 1045-3873
- eISSN
- 1540-8167
- Grant note
- HL57929 / NHLBI NIH HHS HL 70722 / NHLBI NIH HHS K08 HL080106-01 A1 / NHLBI NIH HHS
- Language
- English
- Date published
- 02/2008
- Academic Unit
- Molecular Physiology and Biophysics; Cardiovascular Medicine; Internal Medicine
- Record Identifier
- 9984025699202771
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