1996 Fiscal Year Final Research Report Summary
ESTABL ISHMENT OF DIELECTRIC SPECTROSCOPY FOR INSTANTANEOUS EVALUATING MYOCARDIAL VIABILITY
| Project/Area Number |
07671458
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Thoracic surgery
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| Research Institution | GIFU UNIVERSITY |
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Principal Investigator |
MURAKAWA Shinji Gifu univ.school of Med., First dept.of Surg., research associate, 医学部, 助手 (40229977)
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| Co-Investigator(Kenkyū-buntansha) |
TAKAGI Hisato Gifu univ.school of Med., First dept.of Surg., reseach associate, 医学部・附属病院, 助手 (50262770)
SASAKI Eisaku Gifu univ.school of Med., First dept.of Surg., reseach associate, 医学部・附属病院, 助手 (20273138)
MORI Yoshio Gifu univ.school of Med., First dept.of Surg., reseach associate, 医学部・附属病院, 助手 (40220032)
HIROSE Hajime Gifu univ.school of Med., First dept.of Surg., professor, 医学部, 教授 (20101272)
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| Project Period (FY) |
1995 – 1996
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| Keywords | dielectric spectroscopy / heart preservation / electrical impedance / cardiac transplantation / left ventricular Emax / myocardial ATP |
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| Research Abstract |
The aim of this work is to establish the dielectric spectroscopy for instantaneous evaluating myocardial viability. Canine hearts were immersed in 4ﾟC saline solution (group S) and 4ﾟC UW solution (group U) for 8 hours. We measured the peak value of tan delta loss tangent (tan delta m) of myocardium intermittently. In addition, changes of tan delta were compared with changes of myocardial ATP measured every 2 hours. During preservation the change of tan delta m (%tan delta m) correlated well with the change of ATP (%ATP) [group S : r^2=0.81, group U : r^2=0.66].
And we examined whether tan delta couldpredict ventricular contractility after reperfusion. Preserved porcine hearts were immersed in 4ﾟC saline solution, and tan delta were measured intermittently. Then heterotopic cardiac transplantation followed. During preservation (150 to 360 minutes), the peak value of tan delta (tan delta m) decreased gradually from 5.5(]SY.+-。[)0.5 to 3.8(]SY.+-。[)0.8.Two hours after reperfusion, the tan delta m at the end of preservation was correlated with the percent recovery of left ventricular Emax (%Emax) (r=0.85), while preservation time was not correlated with it (r=0.37). And, changes of tan delta during preservation were compared with myocardial structural changes observed by electron microscopy. The change of tan delta m correlated with the destruction of cellular membrane structure.
Dielectric spectroscopy of myocardium can reflect ischemic injury of cell during preservation. The tan delta m may be useful parameter for evaluation of myocardial viability instantaneously and prediction of the ventricular contractility after reperfusion.
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