Aminosulfonic acid buffer preserves myocardium during prolonged ischemia.
Prevention of myocardial acidosis during global ischemia in operative cardiopreservation was explored in two series of dogs where acid-base control was the only variable. A specifically designed aminosulfonic acid buffer composition, 3:1 molar equivalents NaMOPS to HEPES, 0.2 mol/L, was compared with NaHCO3 (pH 8). Dissolved in standard cardioplegic solution it was given every 30 minutes by coronary infusion at 20 degrees C during 3 hours of global ischemia. Glass electrode intramyocardial pH, adenosine triphosphate (ATP) level, left ventricular contractility (Dp/Dt) and compliance (-Dp/Dt), and other cardiovascular parameters were measured frequently throughout ischemia and for 75 minutes thereafter. In the buffer group (n = 6) myocardial pH remained above entry levels throughout the study period, adenosine triphosphate level remained normal during ischemia, and Dp/Dt and -Dp/Dt at 75 minutes of reperfusion were above entry levels. In the NaHCO3 group (n = 6) pH declined and remained depressed throughout ischemia, adenosine triphosphate level fell steadily and significantly throughout the experiment, and Dp/Dt and -Dp/Dt never regained entry levels. The difference in each parameter between the two groups was statistically significant (p < 0.05). We conclude that control of myocardial acid-base equilibrium alone during global ischemia will preserve myocardial function and minimize reperfusion injury.
Swan
H
H
Department of Surgery, University of Colorado School of Medicine, Denver.
Cowan
M
M
Tornabene
M
M
Owens
L
L
D000138:Acidosis / Q000503:physiopathology / Q000517:prevention & control*; D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D001831:Body Temperature; D002021:Buffers; D002245:Carbon Dioxide / Q000097:blood; D009202:Cardiomyopathies / Q000503:physiopathology / Q000517:prevention & control*; D002314:Cardioplegic Solutions / Q000627:therapeutic use*; D002315:Cardiopulmonary Bypass; D004285:Dogs; D006531:HEPES / Q000627:therapeutic use; D006863:Hydrogen-Ion Concentration; D007511:Ischemia / Q000378:metabolism; D007773:Lactates / Q000032:analysis; D009025:Morpholines / Q000627:therapeutic use; D009200:Myocardial Contraction / Q000502:physiology; D009206:Myocardium / Q000737:chemistry / Q000378:metabolism*; D017693:Sodium Bicarbonate / Q000627:therapeutic use; D013451:Sulfonic Acids / Q000494:pharmacology*; D016277:Ventricular Function, Left / Q000502:physiology; D017725:Ventricular Pressure / Q000502:physiology
D002021:Buffers; D002314:Cardioplegic Solutions; D007773:Lactates; D009025:Morpholines; D013451:Sulfonic Acids; D002245:Carbon Dioxide; C008550:morpholinopropane sulfonic acid; D000255:Adenosine Triphosphate; D017693:Sodium Bicarbonate; C005741:sulfamic acid; D006531:HEPES