Kyoung S. K. Chang

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Aortic regurgitation caused by leaflet perforation is most frequently seen in association with infective endocarditis that involves the aortic valve. There have been occasional reports of iatrogenic aortic regurgitation caused by aortic valve injury after cardiac surgery with the use of the transaortic approach or invasive cardiac procedures. Suture-related(More)
BACKGROUND Pentobarbital decreases the gain of the baroreceptor reflex on the order of 50%, and this blunting is caused nearly entirely by decreasing cardioinhibitory parasympathetic activity. The most likely site of action of pentobarbital is the gamma-aminobutyric acid type A (GABA(A)) receptor. The authors tested whether pentobarbital augments the(More)
The purpose of this study is to compare the speed and ease of establishing intraosseous infusion using a standard bone marrow needle (SBMN; $8) and a new screw-tipped intraosseous needle (Sur-Fast; $42). The study is an experimental design. A total of 42 medical students, without prior IO experience, were recruited as study subjects. Subjects were(More)
Isolated noncompaction of the ventricular myocardium (INVM) is a rare cardiomyopathy resulting from a failure of normal endomyocardial embryogenesis and it has been categorized as a form of unclassified cardiomyopathy. The disorder is characterized by an excessively prominent trabecular meshwork with deep intertrabecular recesses. Although the disorder is(More)
The effect of histamine-induced relaxation on thoracic aortic rings from rats 5, 12, 24 and 52 weeks following streptozotocin-induced diabetes was determined. Preliminary studies confirmed the dependence of histamine-induced relaxation and the independence of nitroglycerin-relaxation (GTN) on the presence of endothelium (EDRF). Diabetes was confirmed by(More)
PURPOSE Cardiac dysfunction and hyperdynamic systemic circulation may be present in patients with cirrhosis. The purpose of this study was to identify relations between plasma levels of N-terminal-proBNP (NT-proBNP), reflecting early ventricular dysfunction, and the severity of liver disease and cardiac dysfunction in cirrhotic patients. MATERIALS AND(More)
BACKGROUND Ketamine increases both blood pressure and heart rate, effects commonly thought of as sympathoexcitatory. The authors investigated the possibility that ketamine increases heart rate by inhibiting the central cardiac parasympathetic mechanisms. METHODS We used a novel in vitro approach to study the effect of ketamine on the identified cardiac(More)
BACKGROUND Ketamine increases blood pressure and heart rate by unknown mechanisms, but studies suggest that an intact central nervous system and arterial baroreceptors are required. In the brain stem, medial nucleus tractus solitarius receives afferents from nodose neurons that initiate cardiovascular autonomic reflexes. Here, the authors assessed ketamine(More)
BACKGROUND Isoflurane inhibits baroreflex control of heart rate (HR) by poorly understood mechanisms. The authors examined whether suprapontine central nervous system cardiovascular regulatory sites are required for anesthetic depression. METHODS The effects of isoflurane (1 and 2 rat minimum alveolar concentration [MAC]) on the baroreflex control of HR(More)
Background: Pentobarbital decreases the gain of the baroreceptor reflex on the order of 50%, and this blunting is caused nearly entirely by decreasing cardioinhibitory parasympathetic activity. The most likely site of action of pentobarbital is the -aminobutyric acid type A (GABAA) receptor. The authors tested whether pentobarbital augments the inhibitory(More)