title: Dielectrical spectroscopy of canine myocardium during acute ischemia and hypoxia at frequency spectrum from 100 kHz to 6 GHz.
abstract: We studied dielectrical properties of canine myocardium during acute ischemia and hypoxia using dielectrical spectroscopy method at frequency spectrum from 100 kHz to 6 GHz. This study was conducted on a group of six canines with acute ischemia and seven canines with hypoxia. Hypoxia (10% for 30 min) decreases myocardial resistance (rho), while the dielectrical permittivity (epsilon') of the myocardial tissue remains statistically unchanged. Acute ischemia for 2 hr causes significant frequency-dependent changes in both epsilon' and rho of myocardial tissue. Myocardial resistance increases, while the sign and amplitude of changes in the myocardial epsilon' are frequency and time dependent. These observations open up an opportunity for assessing the properties of myocardial tissue using dielectrical spectroscopy as well as noninvasively with the help of imaging methods based on electrical impedance and microwave tomography.
authors.affiliation: Biophysical Laboratory, Carolinas Medical Center, Charlotte, NC 28203, USA. ssemenov@carolinas.org
authors.forename: Serguei Y
authors.initials: SY
authors.lastname: Semenov
authors.forename: Robert H
authors.initials: RH
authors.lastname: Svenson
authors.forename: Vitaly G
authors.initials: VG
authors.lastname: Posukh
authors.forename: Alexei G
authors.initials: AG
authors.lastname: Nazarov
authors.forename: Yuri E
authors.initials: YE
authors.lastname: Sizov
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Bulyshev
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Souvorov
authors.forename: Wendy
authors.initials: W
authors.lastname: Chen
authors.forename: Jackie
authors.initials: J
authors.lastname: Kasell
authors.forename: George P
authors.initials: GP
authors.lastname: Tatsis
mesh_terms: D000208:Acute Disease; D000818:Animals; D004285:Dogs; D017097:Electric Impedance; D004574:Electromagnetic Fields; D006321:Heart / Q000503:physiopathology*; D000860:Hypoxia / Q000150:complications / Q000503:physiopathology*; D017202:Myocardial Ischemia / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis / Q000379:methods*