The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Mar 1994
Prevention of complement-induced pulmonary hypertension and improvement of right ventricular function by selective thromboxane receptor antagonism.
The effect of complement activation on the pulmonary vascular system and on right ventricular function was studied in sheep (n = 12) by injection of cobra venom factor. Animals were instrumented for measurement of pulmonary flow, mean pulmonary artery pressure, right ventricular stroke work, arterial blood gases, and systemic vascular resistance. Blood was sampled from the left atrium and pulmonary artery to measure thromboxane B2, the metabolite of thromboxane A2, by radioimmunoassay. ⋯ A pulmonary vascular thromboxane B2 gradient of approximately 1000 pg/ml was measured at 15 and 30 minutes in both control and treated groups. (p < 0.05) We conclude that after complement activation in this model pulmonary hypertension and decreased oxygen tension are mediated by thromboxane release from the pulmonary vascular bed. This increased afterload causes a stress on the right ventricle as demonstrated by the increased right ventricular stroke work. Selective thromboxane receptor antagonism may be a beneficial therapy for pulmonary hypertension in patients after cardiopulmonary bypass.
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J. Thorac. Cardiovasc. Surg. · Mar 1994
Multicenter StudyLong-term outcome of myocardial revascularization in patients with Kawasaki coronary artery disease. A multicenter cooperative study.
The long-term outcome of myocardial revascularization by coronary artery bypass grafting in patients with severe coronary obstruction caused by Kawasaki disease is largely unknown. A multicenter follow-up study was performed in 1991. A total of 168 patients with Kawasaki disease (127 male [75.6%] and 41 female patients [24.4%]) who had undergone coronary bypass grafting were enrolled. ⋯ Late death was strongly related to the absence of an internal thoracic artery graft (p < 0.003) and to the age at the time of operation (p < 0.05). The actuarial patency rate was significantly higher for arterial grafts (77.1% +/- 1.1%, n = 151) than for vein grafts (46.2% +/- 6.3%, n = 126) 85 months after the operation (p < 0.003). Arterial grafts were used for the non-left anterior descending coronary arteries in only 41 of 155 grafts (26.5%); in contrast, vein grafts were used in 85 of 133 grafts (63.9%) (p < 0.005 to 0.001).(ABSTRACT TRUNCATED AT 400 WORDS)
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J. Thorac. Cardiovasc. Surg. · Mar 1994
Comparative StudyDelayed sternal closure after neonatal cardiac operations.
We retrospectively compared the use of primary elective open sternum coupled with delayed sternal closure with the use of primary sternal closure in neonates after cardiac operations. Primary elective open sternum/delayed sternal closure was selectively used in patients who demonstrated hemodynamic or respiratory deterioration, or both, during an intraoperative trial of sternal closure; otherwise primary sternal closure was used. Primary elective open sternum was used in 55 (61.8%) and primary sternal closure in 34 (38.2%) of the 89 patients studied. ⋯ The overall morbidity and duration of inotropic support were not significantly different between the two groups, although seven (20.6%) of the patients with primary sternal closure did have to undergo delayed sternal reopening for refractory postoperative low cardiac output. There was one superficial wound infection in the primary elective open sternum/delayed sternal closure group. Primary elective open sternum/delayed sternal closure is an effective treatment for postoperative neonatal mediastinal compression for the following reasons: (1) the morbidity is low; (2) the mortality of the critically ill group of neonates in whom primary elective open sternum/delayed sternal closure was used was similar to that of the less critically ill primary sternal closure group; and (3) 20.6% of the primary sternal closure group eventually had to undergo delayed sternal reopening to treat refractory postoperative low cardiac output.
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J. Thorac. Cardiovasc. Surg. · Mar 1994
The effects of dynamic cardiac compression on ventricular mechanics and energetics. Role of ventricular size and contractility.
The purpose of this study was to determine the role of ventricular size or contractility in the effectiveness of dynamic cardiac compression in terms of the pressure-volume relationship and myocardial oxygen consumption. In 10 isolated cross-circulated dog hearts, the ventricle was directly compressed during systole. For the volume run, measurements for slope of the end-systolic pressure-volume relation, pressure-volume area, external work, coronary blood flow, and myocardial oxygen consumption were achieved before and during a fixed amount of dynamic cardiac compression. ⋯ Despite the significant differences in the native left ventricular contractility, the increases in slope of the end-systolic pressure-volume relation, pressure-volume area, and external work did not differ among the three groups. We conclude that dynamic cardiac compression enhances left ventricular systolic function independent of ventricular contractility and without affecting coronary blood flow or myocardial oxygen consumption. Mechanical enhancement is more effective in the dilated heart.