Myocardial protection with Hamburg oxygenated crystalloid cardioplegic solution for multiple coronary bypass and multivalvular replacement.

We evaluated myocardial protection with Hamburg oxygenated crystalloid cardioplegic solution in a double study. Part I was a prospective metabolic study, measuring myocardial adenosine triphosphate (ATP) and creatine phosphate (CP) contents before and after ischemia in 30 coronary bypass (CABG) patients. During ischemia, CP levels decreased significantly, whereas ATP did not. After 10 minute of reperfusion, mean ATP contents were 90% of preischemic values and CP levels increased to 85% of preischemic values. Spontaneous myocardial defibrillation was seen in 93.3% of patients. Part II included evaluation of early postischemic myocardial function in 228 patients, 48 with multiple valve replacement (MUVR) and 180 with CABG. Spontaneous myocardial defibrillation was seen in 90.3%. Cardiac index, measured before and 1 and 12 hours after surgery, increased significantly in the postischemic period (from 1.95 +/- 0.9 to 2.5 +/- 0.7 l/min m2 in MUVR, p 0.04; from 2.2 +/- 0.6 to 2.7 +/- 0.7 l/min/m2 in CABG, p 0.01). Myocardial infarction frequency was 3% among CABG patients, and unrelated to the number of distal anastomosis or to aortic cross-clamp time. Early postoperative mortality was 6.2% for MUVR and 0.5% for CABG. Thus, oxygenated cardioplegia with Hamburg solution preserves high-energy phosphate compounds and prevents ischemic injury, with excellent short-term clinical results.