[Clinical and metabolic evaluation of myocardial protection by oxygenated cardioplegia (Hamburg solution) in multiple coronary bypass surgery or polyvalvular replacement].

Myocardial protection by the Hamburg oxygenated crystalloid cardioplegic solution was evaluated. A prospective metabolic study was conducted by measuring the myocardial adenosine triphosphate (ATP) and creatine phosphate (CP) contents by enzymatic techniques in 30 coronary bypass patients with a mean of 3.5 (+/- 0.9) aorto-coronary bypass grafts. Mean aortic cross clamp time was 48.4 (+/- 9.8) min. Myocardial samples were obtained from the left anterolateral ventricular wall: 1 = before CPB, 2 = before aortic cross clamp removal, 3 = 10 min following reperfusion. During ischemia, there was no statistically significant decrease in myocardial ATP contents [3.26 (+/- 0.82) vs 3.01 (+/- 0.92) mumol/g of frozen weight]; in contrast myocardial CP contents decreased significantly [2.71 (+/- 1.44) vs 1.87 (+/- 1.19) mumol/g; p = 0.01]. Following 10 min of reperfusion, the mean ATP level [2.96 (+/- 0.84) mumol/g] was 90% of the preischemic value, and myocardial CP levels (2.32 (+/- 0.92) mumol/g] increased to 85% of preischemic levels. Spontaneous myocardial defibrillation was observed in 93.3% of cases. Early postischemic myocardial function was studied in 228 cardiac operations using the same myocardial protection. 48 patients underwent multiple valve replacement (MUVR), and 180 patients had 4 or more aorto-coronary bypass grafts (CABG). Spontaneous myocardial defibrillation was observed in 90.3% of all; cases; mean CPB time after aortic cross clamp removal was 10.3 (+/- 8) min. Cardiac index by Swan-Ganz thermodilution catheter were measured just before cardiopulmonary bypass and one and twelve hours later.(ABSTRACT TRUNCATED AT 250 WORDS)