A prospective randomised study of continuous warm versus intermittent cold blood cardioplegia for coronary artery surgery: preliminary report

Abstract

Between October 1991 and March 1993, 281 consecutive patients underwent non-emergency isolated coronary artery surgery under the care of one surgeon (A.R.). They were prospectively randomised to receive either intermittent cold (Group I-144 patients) or continuous warm (Group II-137 patients) blood cardioplegia for myocardial protection. There were no significant differences in clinical outcome between the two groups, as judged by operative mortality, rates of peri-operative myocardial infarction, blood loss, need for circulatory support, post-operative neurological deficit, or duration of intensive care or hospital stay. However, sinus rhythm returned spontaneously with greater frequency (91.2% vs 45.8%, P < 0.001) in Group II patients. There was greater transmyocardial oxidative stress in Group I patients, as evidenced by a significant rise in oxidised glutathione in coronary sinus blood on myocardial reperfusion. Also, the serum CKMb isoenzyme level 2 h post-operatively was significantly raised in Group I patients, although this difference had disappeared by the day after surgery. In conclusion this preliminary report suggests that continuous warm blood cardioplegia provides comparable myocardial protection to that achieved with standard hypothermic techniques in patients undergoing coronary artery surgery.

Benefits and Risks of Maintaining Normothermia during Cardiopulmonary Bypass in Adult Cardiac Surgery: A Systematic Review

“…A total of 6731 patients from 44 randomized controlled trials in 14 countries were identified and subject to meta‐analysis (Fig. 1) [12,13,15–63]. All studies were published in English.…”

Functional Recovery of Chronic Ischemic Myocardium after Surgical Revascularization Correlates with Magnitude of Oxidative Metabolism

“…Clinical monitoring of the postischemic human myocardium is focused only on the global myocardial function, systemic hemodynamics and on indirect criteria to assess oxidative stress in the clinical setting [24, 25]. The reason for this lack of information was the inability to monitor cell metabolism in the human myocardium in vivo.…”

The History of Myocardial Protection

“…However, the need to deliver cardioplegia in a near continuous fashion for the normothermic techniques of warm heart surgery led some surgeons to reexamine the retrograde route of administration [161,162]. Coronary sinus perfusion was used initially with crystalloid cardioplegia, and then with blood cardioplegia, and both were used "cold."…”