All-blood (miniplegia) versus dilute cardioplegia in experimental surgical revascularization of evolving infarction

• Published in: Circulation (New York, N.Y.) N.Y.), 2001-09, Vol.104 (12), p.I296
• Main Authors: Velez, Daniel A, Morris, Cullen D, Budde, Jason M, Muraki, Satoshi
• Format: Article
• Language: English
• ISSN: 0009-7322; 1524-4539

BACKGROUND: The advantages of blood cardioplegia include the oxygen-carrying capacity, superior oncotic and buffering properties, and endogenous antioxidants contained in blood. However, the partial dilution of blood in 4:1 (blood:crystalloid) cardioplegic solutions may nullify these advantages and progressively dilute blood during continuous retrograde delivery. This study tested the hypothesis that all-blood (66:1) cardioplegia provides superior myocardial protection compared with dilute (4:1) cardioplegia delivered in a continuous retrograde modality during surgical reperfusion of evolving myocardial infarction. METHODS AND RESULTS: After 60 minutes of left anterior descending coronary artery (LAD) occlusion, anesthetized canines were placed on cardiopulmonary bypass and randomized to either all-blood cardioplegia (AB group) or dilute blood cardioplegia (Dil group). After cross clamping, arrest was induced with 5 minutes of tepid (30 degrees C) antegrade potassium all-blood or dilute blood cardioplegia and maintained with tepid retrograde coronary sinus cardioplegia for a total of 1 hour. The LAD was released after 30 minutes of arrest, simulating revascularization. The cardioplegia hematocrit for the Dil group was lower than that for the AB group (7+/-1% versus 12+/-2%, P