A new method of assessing left ventricular function under assisted circulation using a conductance catheter.
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.
Matsuwaka
R
R
First Department of Surgery, Osaka University Medical School, Japan.
Matsuda
H
H
Nakano
S
S
Shirakura
R
R
Kaneko
M
M
Taniguchi
K
K
Matsuki
O
O
Masai
T
T
Fukushima
N
N
Kawashima
Y
Y
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