Comparison of two strategies for myocardial management during coronary artery operations

• Published in: The Annals of thoracic surgery Vol. 58; no. 3; pp. 768 - 772
• Main Authors: Anderson, Jonathan R., Hossein-Nia, Mojgan, Kallis, Panny, Pye, Maurice, Holt, David W., Murday, Andrew J., Treasure, Tom
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.09.1994
• Subjects: Aged; Anastomosis, Surgical; Biomarkers - blood; Coronary Artery Bypass - methods; Creatine Kinase - blood; Female; Heart Arrest, Induced; Humans; Hypothermia, Induced; Isoenzymes; Male; Middle Aged; Myocardial Ischemia - blood; Myocardial Ischemia - enzymology; Myocardial Ischemia - etiology; Myocardial Reperfusion - methods; Myocardial Reperfusion Injury - blood; Myocardial Reperfusion Injury - enzymology; Myocardial Reperfusion Injury - prevention & control; Prospective Studies; Time Factors; Troponin - blood; Troponin T; Ventricular Fibrillation - blood; Ventricular Fibrillation - enzymology; Ventricular Fibrillation - etiology
• ISSN: 0003-4975; 1552-6259
• DOI: 10.1016/0003-4975(94)90745-5

Despite the current trend for using blood cardioplegia, ventricular fibrillation with intermittent ischemia is still used as a strategy to manage the myocardium with impressive results. These two methods of myocardial management were compared in 40 patients undergoing elective coronary artery operations using creatine kinase MB isoforms and troponin T assays. Each patient was randomized to have either cold blood cardioplegia (n = 20) or ventricular fibrillation with intermittent ischemia (n = 20) for myocardial management during the construction of distal anastomoses. Until recently, the comparison of different methods of myocardial management has been hindered by the lack of a specific and sensitive marker of myocardial damage. Analysis of creatine kinase MB isoforms (MB2, cardiac tissue form; MB1, plasma-modified form) and cardiac-specific troponin T (a structural protein) has been shown to improve the sensitivity for the detection of myocardial damage. There were no significant differences between the two groups in age, sex ratio, extent of disease, or left ventricular function. Blood samples for analysis were collected before cross-clamp application and at time intervals up to 48 hours after. Median peak creatine kinase MB2 activity was found to be significantly higher in the blood cardioplegia group compared with ventricular fibrillation (26.5 U/L versus 19.5 U/L, respectively, p = 0.04). Although median peak troponin T concentration was higher in the blood cardioplegia group, the difference failed to reach significance (22. ng/mL versus 1.6 ng/mL, p = 0.15). The area under the time-activity curves (a reflection of total release) constructed for creatine kinase MB, MB2, and troponin T were not significantly different between the groups ( p = 0.51, 0.82, and 0.31, respectively). These results suggest that, for elective coronary artery operations, ventricular fibrillation is as effective a strategy to manage the myocardium as blood cardioplegia and it may even be superior.