title: A new method of assessing left ventricular function under assisted circulation using a conductance catheter.
abstract: A new method of assessing left ventricular (LV) systolic function without terminating assisted circulation (AC) was investigated using a LV volume catheter (conductance catheter) in canine cardiopulmonary bypass (CPB) (Group 1, n = 7) and left heart bypass (LHB) (Group 2, n = 5) models. The hearts were subjected to either 20 min of global ischemia (IS), with a subsequent 80 min of reperfusion under CPB, or regional IS under LHB. Instantaneous LV pressure-volume data acquisitions were repeated during transient (15 sec) acute volume loading without terminating bypass. The relationship between the stroke work (SW), determined as the area of the pressure-volume loop, and the end-diastolic volume (EDV), were highly linear at every study point (mean: r = 0.956-0.986 in Group 1, r = 0.974-0.987 in Group 2). The slopes of SW and EDV (preload recruitable stroke work: PRSW) significantly decreased after IS, in both Group 1 and Group 2. In conclusion, measurement of PRSW without terminating bypass seemed to be useful in evaluating LV systolic function in patients under AC.
authors.affiliation: First Department of Surgery, Osaka University Medical School, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Matsuwaka
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
authors.forename: S
authors.initials: S
authors.lastname: Nakano
authors.forename: R
authors.initials: R
authors.lastname: Shirakura
authors.forename: M
authors.initials: M
authors.lastname: Kaneko
authors.forename: K
authors.initials: K
authors.lastname: Taniguchi
authors.forename: O
authors.initials: O
authors.lastname: Matsuki
authors.forename: T
authors.initials: T
authors.lastname: Masai
authors.forename: N
authors.initials: N
authors.lastname: Fukushima
authors.forename: Y
authors.initials: Y
authors.lastname: Kawashima
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization / Q000295:instrumentation*; D002408:Catheters, Indwelling; D004285:Dogs; D006353:Heart-Assist Devices; D008838:Microcomputers; D008955:Models, Cardiovascular; D009200:Myocardial Contraction / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D016276:Ventricular Function