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PubMed · 12085014

Brain death impairs coronary endothelial function.

Gabor Szabo·Volker Buhmann·Susanne Bahrle·Christian F Vahl·Siegfried Hagl
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Abstract

BACKGROUND: To characterize the impact of brain death (BD) on endothelial dysfunction after cardiac transplantation we investigated coronary circulation and vasomotor function in a canine model. METHODS: Left ventricular pressure-volume data (conductance catheter) and coronary blood flow (CBF) were monitored continuously. Endothelium-dependent vasodilatation after acetylcholine and endothelium-independent vasodilation after sodium nitroprusside were assessed before and 3 hr after BD induction (inflation of a subdural balloon). RESULTS: BD led to an initial hyperdynamic reaction with significant (P<0.05) increase of CBF. After 3 hr, CBF decreased significantly (P<0.05). Although before BD, application of acetylcholine led to a monophasic vasodilatative response, after BD a short mild vasodilatation was followed by a longer vasoconstriction. Endothelium-independent vasodilatation remained unchanged. CONCLUSIONS: BD affects coronary circulation by two means: (1) impairment of CBF to decrease in parallel in afterload with consecutive hemodynamic deterioration and (2) severe endothelial dysfunction that may be a contributing factor to posttransplant outcome.

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AcetylcholineAnimalsBrain DeathCoronary CirculationCoronary VesselsDogsEndothelium, VascularHeart TransplantationHemodynamicsNitroprussidePostoperative ComplicationsVasodilationVasodilator AgentsJournal ArticleResearch Support, Non-U.S. Gov't

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Gabor Szabo, Volker Buhmann, Susanne Bahrle, Christian F Vahl, Siegfried Hagl. 2002-06-15. Brain death impairs coronary endothelial function.. https://doi.org/10.1097/00007890-200206150-00027

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