Cold blood versus cold crystalloid cardioplegia: a prospective randomised study of 345 aortic valve patients

Although experimental studies have indicated that blood cardioplegia may be superior to crystalloid cardioplegia for myocardial protection, clinical data still remain uncertain. In a previous randomised study from our institution, including 1440 patients undergoing coronary artery bypass grafting (CABG), no beneficial effects of blood cardioplegia were seen in any relevant outcome variables. The investigation was therefore extended to a patient population having longer pump times and ischaemic periods.

Over a 48-month period, all patients undergoing aortic valve replacement with or without CABG performed by two surgeons, were prospectively randomised to receive either intermittent cold retrograde blood cardioplegia (group B) or intermittent cold retrograde crystalloid cardioplegia (group C) during aortic cross-clamping.

A total of 345 patients aged 28-90 years (median, 72 years) entered the study (group B, n=172, group C, n=173). All relevant demographic and operative variables were similar for both groups. As for the clinical course, no statistically significant differences were seen concerning spontaneous sinus rhythm after aortic declamping, use of inotropic drugs, duration of ventilatory support, bleeding and rate of allogeneic blood transfusions, perioperative myocardial infarction, episodes of atrial fibrillation, stroke or minor neurological dysfunction, renal function, infections, physical rehabilitation or mortality. Further, in the patients with the longest ischaemic times, no statistically significant differences between the groups could be demonstrated.

There were no indications that retrograde cold blood cardioplegia was superior to retrograde cold crystalloid cardioplegia patients undergoing aortic valve replacement, with or without CABG.