MYOCARDIAL-FUNCTION IN EARLY HOURS AFTER CORONARY-ARTERY BYPASS-GRAFTING - COMPARISON OF 2 CARDIOPLEGIC METHODS

The theoretical advantages of retrograde blood cardioplegia combined w ith anterograde blood cardioplegia and warm reperfusion before aortic unclamping during coronary surgery were evaluated in 41 patients (grou p 2). The early postoperative myocardial function of this group was co mpared with that of 55 patients (group 1) in whom cold crystalloid car dioplegia was administered. The following variables were measured and analyzed by multivariate statistical analysis: heart rate, left atrial pressure, systemic arterial pressure, cardiac index, left ventricular stroke work index, ventricular function, oxygen delivery, hemoglobin, partial oxygen pressure in mixed venous blood, arteriovenous oxygen d ifference, carbon dioxide production per square meter, and cardiac iso enzyme of creatine-kinase. The myocardial function improved progressiv ely and cardiac enzymatic release was low for both groups 9 hours afte r admission to the intensive care unit. However, group 2 had significa ntly higher oxygen delivery, carbon dioxide production per square mete r, cardiac index, left ventricular stroke work index, and ventricular function and significantly lower left atrial pressure and mean systemi c arterial pressure than that of group 1. The best separation of group 2 from group I occurred at the ninth hour, with a probability of corr ect recognition of 92.1%.