The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Aug 1992
Comparative StudyResponses of human gastroepiploic arteries to vasoactive substances: comparison with responses of internal mammary arteries and saphenous veins.
We examined the responses of human gastroepiploic arteries to histamine, serotonin, and norepinephrine, comparing those of internal mammary arteries and saphenous veins. Fresh specimens of the vessels were obtained intraoperatively from 21 patients. The vessels were suspended in organ chambers to record isometric tensions. ⋯ With the gastroepiploic artery, the responses to norepinephrine and serotonin were similar to those of the internal mammary artery. Histamine induces endothelium-dependent relaxations only, and histaminergic receptors that induce contractions may be absent on vascular smooth muscle cells. These vasoactive properties may contribute to the high patency as a coronary graft.
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J. Thorac. Cardiovasc. Surg. · Aug 1992
Comparative StudySimilar endothelium-dependent relaxation, but enhanced contractility, of the right gastroepiploic artery as compared with the internal mammary artery.
The right gastroepiploic artery is an alternative coronary bypass graft. The excellent graft function of the internal mammary artery has been related to its physiologic properties, particularly to endothelial function. Isolated artery rings were suspended in organ chambers for recording of isometric tension. ⋯ The relaxation to the nitric oxide donor SIN-1 was identical in the two arteries. Thus the right gastroepiploic artery exhibits better contractility than the internal mammary artery but comparable endothelium-dependent and endothelium-independent relaxations. The good endothelial function of the gastroepiploic artery might be important for graft function and patency, whereas the enhanced contractility may facilitate vasospasm, especially in the presence of high circulating levels of catecholamines.
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J. Thorac. Cardiovasc. Surg. · Aug 1992
Comparative StudySuperior qualities of University of Wisconsin solution for ex vivo preservation of the pig heart.
The components of the University of Wisconsin solution have the potential to enhance and extend heart preservation. We have evaluated University of Wisconsin solution by comparing it with St. Thomas' Hospital cardioplegic solution in the isolated pig heart subjected to 8 hours of ischemia at 4 degrees C (n = 6 in each). ⋯ Myocytes from hearts receiving University of Wisconsin solution, unlike those given St. Thomas' Hospital solution, showed relaxed myofibrils with prominent I-bands. We conclude that University of Wisconsin solution has the potential to improve the preservation of the heart and possibly prolong the ischemic period in clinical cardiac transplantation.
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Between December 1982 and March 1990, 65 patients with active infective endocarditis underwent cardiac operations. Their mean age was 28.6 years (range 1 to 65 years). The most common infecting organisms were staphylococcus (33.8%), streptococcus (18.5%), and brucella (16.9%); 11 patients (16.9%) had cultures negative for infection. ⋯ There was one late death. Early operation should always be considered in active infective endocarditis, especially when a prosthetic valve is involved or the infecting organism is staphylococcal or fungal. The disclosure of moderate to large vegetations by two-dimensional echocardiography is an indication for operation.