The erythrocyte-perfused "working heart" model: hemodynamic and metabolic performance in comparison to crystalloid perfused hearts.
A brief period of ischemia was used to evaluate an erythrocyte-enriched Krebs-Henseleit (KH) buffer (n=8) compared to KH only (n=8) in an isolated working rabbit heart. Experimental protocol was as follows: preischemic baseline, 5 min of global ischemia followed by 45 min of reperfusion. Preischemic heart rate was identical, coronary flow was significantly lower (2.7 versus 5.6 mL/min/g wet wt, p<0.01), the other hemodynamic and biochemical values were significantly higher in erythrocyte-perfused hearts: aortic flow 23.5 versus 12.0, p<0.01; cardiac output 26.2 versus 17.6, p<0.01; all in mL/min/g wet wt; dp/dt max 1286 versus 997 mmHg/s, p<0.01; myocardial oxygen consumption 3.5 versus 2.3 micromol/min/g wet wt, p<0.05. During early reperfusion, in the erythrocyte-perfused hearts, coronary flow further increased (p<0.003), the other hemodynamic parameters returned to baseline values in both groups. High-energy phosphates showed significantly higher values (ATP 2.0+/-0.1 versus 1.3+/-0.1, p<0.05; CrP 2.0+/-0.2 versus 1.6+/-0.1, p<0.05 all in micromol/g wct wt), water content was significantly lower (81% versus 74%, p<0.05) in erythrocyte-perfused hearts. It can be concluded that the erythrocyte-perfused working heart model provides excellent oxygenation, leading to superior hemodynamic and metabolic performance. Additionally, in the erythrocyte-perfused hearts preservation of coronary flow reserve underlines the physiological competency of this preparation.
Podesser
B K
BK
Department of Cardiothoracic Surgery, University of Vienna, AKH Wien, Austria. Bruno.Podesser@akh-wien.ac.at
Hallström
S
S
Schima
H
H
Huber
L
L
Weisser
J
J
Kröner
A
A
Fürst
W
W
Wolner
E
E
D000227:Adenine Nucleotides / Q000378:metabolism; D000818:Animals; D001834:Body Water / Q000378:metabolism; D002021:Buffers; D003331:Coronary Vessels / Q000502:physiology; D004912:Erythrocytes / Q000502:physiology*; D006321:Heart / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D008955:Models, Cardiovascular; D017202:Myocardial Ischemia / Q000378:metabolism / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000503:physiopathology; D009206:Myocardium / Q000378:metabolism; D010101:Oxygen Consumption; D010477:Perfusion / Q000295:instrumentation / Q000379:methods*; D011817:Rabbits; D014655:Vascular Resistance / Q000502:physiology
D000227:Adenine Nucleotides; D002021:Buffers