Myocardial protection during cardiac operations

Abstract

The efficacy of myocardial protection with a single aortic crossclamp and blood cardioplegia was evaluated in 819 consecutive patients stratified for preoperative condition by means of a new clinical risk scoring system. A protocol using either antegrade or antegrade/retrograde blood cardioplegia was compared with antegrade crystalloid cardioplegia in 2582 similar, consecutive, and concurrent patients. In the blood cardioplegia cohort, 97 (11.8%) patients had 129 complications compared with 407 (15.8%) patients and 675 complications in the crystalloid cardioplegia group (p = 0.006). In high-risk patients, combined antegrade/retrograde cardioplegia significantly reduced myocardial infarction, stroke, and respiratory and wound complications. Despite the significantly longer aortic crossclamp time required for blood cardioplegia, patients undergoing crystalloid cardioplegia were 1.7 (95% confidence interval 1.3, 2.1) times more likely to have a morbid event. Time in the intensive care unit, length of hospitalization, and length-of-stay outlier status were significantly decreased in the blood cardioplegia compared with the crystalloid cardioplegia group. The net savings in hospital cost amounted to $2196 per case. When compared separately with crystalloid cardioplegia, combined antegrade/retrograde blood cardioplegia accounted for most of the morbidity reduction by significantly reducing perioperative myocardial infarction, wound complications, and length of stay in patients having reoperations. Antegrade/retrograde blood cardioplegia did not influence 1-year survival or event-free survival, even when risk was considered.