We investigated the effects of milrinone administered during cardiopulmonary bypass (CPB) for open heart surgery. Ten patients (group M) received milrinone after aortic declamping during CPB. Ten other patients served as controls with no administration (group C). Soon after the bolus infusion of milrinone, the perfusion pressure dropped significantly in the M group, however, after CPB and at the end of operation, aortic pressure showed no difference between the two groups. There were no differences in heart rate, pulmonary artery pressure and pulmonary capillary wedge pressure. After CPB, cardiac index was high and systemic vascular resistance index was low in the M group. The need for cathecholamine and time for rewarming showed also no significant differences. No adverse reaction was recognized. During CPB, a single administration of milrinone was useful for peri- and post-operative management of patients undergoing open heart surgery.

An 81-year-old patient, who had a postinfarction left ventricular aneurysm with thrombus underwent left ventricular aneurysmectomy with right coronary artery bypass grafting (CABG). Preoperative examination showed 99% stenosis of the left coronary artery (#7) and 90% stenosis of the right coronary artery (#3). The operation was performed because angina was not improved and formation of thrombus was suspected on the wall of the aneurysm. The operation was performed under cardiopulmonary bypass and by antegrade and continuous retrograde cardioplegia. The aneurysm was resected and a relatively fresh thrombus which was detected on the endocardium of the aneurysm was extracted. The left ventricle was closed by direct linear suture with felt reinforcement. Because the area of resection included part of the left anterior descending artery, only right CABG (#3) with a saphenous vein was done. Weaning from bypass was very easy and the postoperative course was uneventful.

Using the DDG-2001 pulse dye densitometer, cardiac output (CO) and circulating blood volume (BV) were determined before and after the operation, and its accuracy and the significance of postoperative management were studied. Referring to 14 cases undergoing open heart surgery, CO and BV were determined using the DDG-2001 before application of the cardiopulmonary bypass and immediately, 4h and 12h after the operation. The level of CO was compared with that determined by the thermodilution method, and the level of BV with that calculated from hemoglobin levels determined before and after the cardiopulmonary bypass application and the priming volume in the circuit. Further, body fluid balance after the operation was calculated, and its relation to BV was studied. As to the correlation coefficient and inclination of the regression line, they were 0.77 and 0.849 with CO, and 0.821 and 0.844 with BV, respectively. Upon completion of the operation BV decreased, but increased again 4h and 12h later, although the body fluid balance was negative. CO and BV determined by the pulse dye densitometry favorably correlated with those determined by other methods. Immediately after the operation BV decreased, but then increased in the course of time, although the body fluid balance was negative.

Coronary artery bypass surgery and abdominal aortic aneurysm repair were performed simultaneously during cardiopulmonary bypass in two patients with severe left ventricular dysfunction. Both patients underwent coronary artery bypass surgery first, followed by abdominal aortic aneurysm repair during cardiopulmonary bypass. Combined surgery is reasonable for patients with combined coronary artery disease and abdominal aortic aneurysm. Aortic aneurysm repair during cardiopulmonary bypass for patients with severe left ventricular dysfunction also appears safe and effective.