The Journal of Thoracic and Cardiovascular Surgery, Vol 96, 725-729, Copyright © 1988 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Right and left ventricular metabolites
KH Teoh, JC Mullen, RD Weisel, GT Christakis, MM Madonik, J Ivanov and DA Mickle
Division of Cardiovascular Surgery, Toronto General Hospital, Ontario, Canada.
Current methods of cardioplegic delivery may delay the recovery of right
ventricular metabolism and function. To evaluate right and left ventricular
metabolism, we performed biopsies in 37 patients undergoing elective
coronary bypass operation with aortic root blood cardioplegia. Right
ventricular temperatures were warmer than left ventricular temperatures
during cardioplegic arrest (right ventricle: 16.8 degrees +/- 3.8 degrees
C, left ventricle: 14.3 degrees +/- 3.7 degrees C, p = 0.02). Adenosine
triphosphate concentrations were lower in the right ventricle than in the
left ventricle before cardioplegic arrest (right ventricle: 13.8 +/- 7.8
mmol/kg, left ventricle: 21.5 +/- 8.7 mmol/kg, p = 0.02). After
reperfusion, right ventricular adenosine triphosphate concentrations fell
to low levels (10 +/- 6 mmol/kg). Postoperative left and right ventricular
high energy phosphate concentrations (the sum of adenosine triphosphate and
creatine phosphate levels) correlated inversely with myocardial
temperatures during cardioplegia (r = -0.29, p = 0.048). Aortic root
cardioplegia did not cool the right ventricle as well as it did the left
ventricle. The lower preoperative high energy phosphate concentrations may
have increased the susceptibility of the right ventricle to ischemic
injury. Alternative methods of myocardial preservation may improve right
ventricular cooling and protection.