Effects of Blood and Crystalloid Cardioplegia on Cardiac Function at Organ and Cellular Levels During Hypothermic Cardiac Arrest

Abstract

The present investigation was undertaken to compare the effects of cold crystalloid and blood cardioplegia on the functional recovery of the heart; on Ca++ binding and uptake, Ca++-ATPase of the sarcoplasmic reticulum (SR), and sarcolemmal (SL) ATPase; and on serum MB fraction of creatine kinase (MBCK) after one and half hours of reperfusion following one hour of ischemic cardiac arrest in dog. This study was made also to determine if the functional changes are related to the changes in biochemistry at the molecular level. The dogs were divided into three groups: sham bypass (SB), cold crystalloid cardioplegia (CC), and pump blood cardioplegia (PB). There was a decrease in the cardiac index (CI), left ventricular work index (LVWI), and mean aortic pressure (MAP) in all three groups. The index of myocardial contractility [dp/dt)/IIP) and CI were lower in the CC group as compared with the SB and PB groups. All the hemodynamic values for the PB group were similar to those of the SB group except total systemic vascular resistance (TSVR) and left ventricular end-diastolic pressure (LVEDP) which were lower in the PB group. The index of myocardial contractility and cardiac index appeared to be greater in the PB group than in the CC group. There was a decrease in the Ca++ uptake by SR from both the CC and PB groups. Ca++ binding and Ca++,-ATPase of SR from the PB group were depressed. The sarcolemmal ATPase was unaffected in both groups. The serum MBCK increased in both PB and CC groups, though the increase was smaller in the PB group. These results indicate that the functional recovery of the heart was slightly better with pump blood cardioplegia than with cold crystalloid cardioplegia. The depressed myocardial contractility and cardiac function in the CC group were associated with a decrease in the Ca++ uptake by SR. However, the decreases in the Ca++ binding, Ca++ uptake, and Ca++ ATPase by SR from the pump blood cardioplegic group were not accompanied by decreases in the cardiac contractility and cardiac function. Myocardial damage as assessed by serum MBCK was smaller in the PB group than in the CC group.

Circulatory Arrest under Hypothermic Anesthesia Using Abdominal Cavity Cooling.

“…Previous studies have shown that sufficient brain and myocardial protection during circulatory arrest can lead to good prognosis with or without CPB [2,16,20,21,24]. It was reported that protection of the myocardium and the brain is the most important factor governing the success of * * * * facts that the peritoneal area is almost equal to the body surface area, and that the peritoneal blood supply is more abundant than the supply to the body surface [15,22].…”

Comparative Study of Five Blood Cardioplegia Systems

“…Adequate myocardial protection as accomplished by efficient delivery systems is crucial to the post-operative course of the patient (1)(2)(3). While some of the advantages of blood cardioplegia remain theoretical and/or controversial, many experimental and clinical studies indicate a superiority in myocardial protection when compared to crystalloid cardioplegia (4)(5)(6)(7)(8). Myocardial preservation may be enhanced by blood cardioplegia's increased capacity to carry oxygen, natural buffers, oncotic constituents, and antioxidants (9)(10)(11)(12)(13).…”