The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Jul 1992
Effects of coronary artery bypass grafting on global and regional myocardial function. An intraoperative echocardiographic assessment.
The immediate effect of coronary artery bypass grafting on global and regional myocardial function was studied by means of epicardial two-dimensional echocardiography during operations in 20 patients. Echocardiograms were recorded before cardiopulmonary bypass and 5 and 30 minutes after bypass. Global left ventricular function was expressed as percent short-axis area change and regional function as percent fractional area change. ⋯ This improvement was maintained 30 minutes after bypass (22.8% +/- 1.5%, p less than 0.001). We conclude that coronary revascularization exhibits an immediate beneficial effect on chronically underperfused myocardium having severely depressed baseline function. However, in normal and moderately hypokinetic areas, the depressant effects of global ischemia and reperfusion prevail in the immediate postbypass period, leading to a global depression of cardiac function.
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J. Thorac. Cardiovasc. Surg. · Jul 1992
Hematologic changes during and after cardiopulmonary bypass and their relationship to the bleeding time and nonsurgical blood loss.
The hemostatic dysfunction induced by cardiopulmonary bypass is due, in part, to a platelet dysfunction evidenced by a postoperative extension of the bleeding time; it leads to increased postoperative blood loss and morbidity. This study, which was conducted in 85 patients undergoing cardiopulmonary bypass, was designed to characterize the hematologic changes during and after cardiopulmonary bypass and to elucidate the relationships between these changes, the extension of the bleeding time, and the magnitude of the postoperative nonsurgical blood loss. Variables were measured before, during, and 2, 24, 48, and 72 hours after cardiopulmonary bypass. ⋯ In addition, the postoperative bleeding time correlated with the skin temperature and the plasma level of D-dimer, while the postoperative blood loss also correlated with temperature and the plasma levels of C3. These data establish a direct relationship between the postoperative bleeding time, the postoperative blood loss, and temperature. They indicate that the reversal of the postoperative extension of the bleeding time is due in part to rewarming and to the release of larger platelets into the circulation, and they suggest that hyperfibrinolysis and complement activation may play an important role in the cardiopulmonary bypass-induced platelet dysfunction.
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J. Thorac. Cardiovasc. Surg. · Jul 1992
Comparative StudyAortic valve replacement. Aortic root versus coronary sinus perfusion with blood cardioplegic solution.
The role of retrograde coronary sinus cardioplegia in patients undergoing aortic valve replacement for aortic stenosis alone or in combination with myocardial revascularization has not been fully defined. Sixty-three patients undergoing elective aortic valve replacement received cold potassium blood cardioplegic solution via either the aortic root (36 patients) or the coronary sinus (27 patients). The patients were similar with respect to age, degree of aortic stenosis, ventricular function, severity of coronary artery disease, crossclamp time, completeness of revascularization, and mean volume and temperature of the infusion solution. ⋯ Right and left ventricular function was preserved equally in the two groups, and volume-loading studies suggested improved diastolic performance in patients having retrograde cardioplegia. There were no differences between the two groups with respect to clinical outcome. We conclude that coronary sinus cardioplegia is as safe as aortic root perfusion for myocardial preservation in patients undergoing elective aortic valve replacement.
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J. Thorac. Cardiovasc. Surg. · Jul 1992
Equivalent eighteen-hour lung preservation with low-potassium dextran or Euro-Collins solution after prostaglandin E1 infusion.
Improved techniques of pulmonary preservation would help alleviate the critical shortage of donor organs in lung transplantation and would improve early graft function. A previous study demonstrated that cold pulmonary artery flush with low-potassium dextran solution was superior to Euro-Collins solution in preservation of canine lung allografts stored for 12 hours when no pulmonary vasodilator was used before donor lung flush. The present study was designed to determine whether donor pretreatment with prostaglandin E1 would affect the superiority of low-potassium dextran as a preservation solution. ⋯ Lungs flushed and stored in Euro-Collins or low-potassium dextran solution provided equivalent gas exchange function on day 0 (arterial oxygen tension: Euro-Collins 289 +/- 105 mm Hg versus low-potassium dextran 265 +/- 111 mm Hg; mean +/- standard error of the mean) and on day 3 (Euro-Collins 516 +/- 45 mm Hg versus low-potassium dextran 354 +/- 77 mm Hg; p = 0.10). Mean pulmonary artery pressures in the transplanted lung were not significantly different in the Euro-Collins and low-potassium dextran groups on day 0 (21.4 +/- 2 mm Hg versus 33.7 +/- 5 mm Hg, respectively; p = 0.09) or on day 3 (20.2 +/- 2.7 mm Hg versus 24.2 +/- 5.1 mm Hg, respectively; p = 0.50). We conclude that there was no advantage of low-potassium dextran over Euro-Collins as a flush solution in this 18-hour canine single lung allograft model in which prostaglandin E1 was administered before pulmonary artery flush.