title: Effects of hypoxia and reoxygenation on maximum rate of early left ventricular filling.
abstract: Left ventricular early filling during hypoxia and reoxygenation was examined in isolated working rat hearts that contracted 300 times/min when perfused with Krebs-Henseleit solution at 37 degrees C. Left ventricular short-axial diameter (LVD = D) was measured with a pair of ultrasonic crystals. The maximum lengthening velocity of LVD [(dD/dt)max] decreased with hypoxia and recovered after reoxygenation (from a control of 20.3 +/- 6.7 to 7.3 +/- 1.7 mm/s after 15 min of hypoxia and to 16.3 +/- 8.1 mm/s after 15 min of reoxygenation; n = 7). However, (dD/dt)max/delta D (where delta D is systolic shortening) showed no significant change with either hypoxia or reoxygenation (from a control of 21.0 +/- 2.9 l/s to 22.2 +/- 2.7 l/s after 15 min of hypoxia and to 22.5 +/- 3.7 l/s after 15 min of reoxygenation; n = 7). Therefore, we concluded that the changes of (dD/dt)max with hypoxia and reoxygenation were caused by the changed systolic shortening and that left ventricular myocardial recoil, expressed by (dD/dt)max/delta D, showed no change with either hypoxia or reoxygenation.
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Kyoto University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kusunoki
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Konishi
authors.forename: C
authors.initials: C
authors.lastname: Kawai
mesh_terms: D000818:Animals; D001794:Blood Pressure; D006321:Heart / Q000502:physiology*; D006352:Heart Ventricles / Q000503:physiopathology; D000860:Hypoxia / Q000503:physiopathology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D016276:Ventricular Function