• Journal of Chest Surgery
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• v.29 no.2
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• pp.136-146
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• 1996

Studies on normal human embryos and on malformed human hearts have been two main sources of the information on the developmental cardiology, Recent advances in the biological technology has opened a new era and descriptive embryology is being shifted into dynamic developmental biology. In this review, we discuss the current understanding on the cardiac embryology relevant to clinical practices of pediatric cardiology. Classical cardiac embryology starts with understanding on five segments of a straight heart tube : the sinus venosus, the primitive atria, the embryonic left ventricle, the embryonic right ventricle and the truncus arteriosus. Key steps in the normal morphogenetic process are the complex spiral septation of ventriculoarterial junction and two jumping connections : between the embryonic right atrium and embryonic right ventricle, and between the embryonic left ventricle and the aorta. Only after these two steps are successfully completed, the third fetal stage tak s place, when myocardial growth and remodeling take place There are two outstanding progresses on the cardiac embryology during recent five-year period. One is immunohistochemical mapping of the conduction system in the developing heart and the other is the understanding on the neural crest cell migration followed by molecular detection of the microdeletion of chromosome 22. A balanced progress of classical morphological studies, modern biological technics and advanced clinical medicine is an urgent task for doctors and scientists dealing with children with sick hearts.

• Journal of Yeungnam Medical Science
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• v.22 no.1
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• pp.13-26
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• 2005

Atrial fibrillation (AF) is the most common cardiac rhythm disturbance, which carries significant cardiovascular morbidity and mortality. The medical treatment for AF is cumbersome and unsatisfactory, which has highlighted the need to develop alternative treatments for AF. The recent discovery that AF is often initiated by atrial ectopic beats has resulted in treatments designed to target the ectopic sources, particularly those within the pulmonary veins. Building on the pioneering work of Cox et al., a recent reported series demonstrated the feasibility of treating patients undergoing cardiac surgery for other structural heart diseases with limited, left-atrial ablation lesion sets using alternative energy sources. As less complex modifications of the Maze procedure have been developed, a number of energy sources have been introduced to create of electrically isolating lesions within the atria. These sources have been used both endocardially in arrest heart procedures as well as epicardially in a beating heart setting. This review summarizes the recent advances in surgery for AF that will aid in the development of an effective, minimally invasive surgical procedure to cure patients with AF.

• Korean Journal of Veterinary Research
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• v.43 no.2
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• pp.307-310
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• 2003

An atrial septal defect (ASD) is congenital heart disease with a communication between the atria, which allows blood to shoot from the atrium with pressure. A 3-month-old female Miniature Schunauzer was referred to the Veterinary Teaching Hospital of Konkuk University for the evaluation of systolic heart murmur. At presentation, the mucous membrane was cyanotic. On physical examination, an ejection-type systolic murmur was auscultated at the pulmonic area. In addition, thoracic radiography showed enlargement of main pulmonary artery and right atrial/ventricular enlargement. Echocardiography revealed dilated right atrium and atrial septal defect. However, mitral and tricuspid valve were still intact and well tolerating. The presence of an ASD was confirmed by identifying flow across the defect with color Doppler imaging. Doppler echocardiography provides a means of non-invasive documentation and quantification of ASD. Complete blood count and serum chemistry were not remarkable. Although large defect was confirmed between the two atrium, the patient did not show any obvious clinical signs of heart failure at this time.

• Journal of Biomedical Engineering Research
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• v.29 no.5
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• pp.343-347
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• 2008

Thermal conductivity, thermal diffusivity were measured in the atrium of a swine heart. Radiofrequency (RF) catheter ablation in an atrium has rapidly emerged at the treatment of symptomatic reentrant arrhythmia associated with accessory pathway or Atrioventricular (AV) node conduction. The thermal properties of an atrium are definitely necessary for these treatments because, in thermal treatments, conductivity and diffusivity are significant factors in the relationship between the applied RF power and the resulting atrium temperature rise. Thermal properties were measured using a self-heated thermistor probe. Thermistor probes were inserted into the tissue of interest and were used to supply heat within the tissue as well as to monitor the temperature rise in the tissue. The measurements were performed at temperatures of 25, 37, $50^{\circ}C$. Atrium thermal conductivity ranged from 5.17$\pm$0.12 mW/cm$^{\circ}C$ at $25^{\circ}C$ to 5.33$\pm$0.08 mW/cm$^{\circ}C$ at $37^{\circ}C$. Atrium thermal diffusivity ranged from 0.00132$\pm$0.00007$cm^2$/sec at $25^{\circ}C$ to 0.00138$\pm$0.00003 $cm^2$/sec at $50^{\circ}C$. This paper also present the thermal property comparison of both chambers of a heart (ventricle and atria).

• Biomolecules & Therapeutics
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• v.5 no.4
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• pp.390-401
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• 1997

In order to investigate the pharmacological properties of New Woohwangchungsimwon Liquid (NCL), effects of Woohwangchungsimwon Liquid (CL) and NCL were compared. In isolated rat aorta, NCL and CL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) without regard to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxation of NCL and CL. NCL and CL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NCL and CL significantly decreased heart rate. NCL and CL, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NCL and CL had no effects on parameters of action potential at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NCL and CL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between two preparations.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.66-78
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• 1999

In order to investigate the pharmacological properties of New Wonbang Woohwangchungsimwon Liquid (NSCL), effects of Wonbang Woohwangchungsimwon Liquid (SCL) and NSCL were compared. In isolated rat aorta, NSCL and SCL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) regardless to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxing effect of NSCL and SCL. NSCL and SCL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NSCL and SCL significantly decreased heart rate. NSCL and SCL, at high doses, had a negative inotropic effect that was a decrease of left ventricular developed pressure and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NSCL and SCL had no effects on parameters of action potential such as resting membrane potential, action potential amplitude, APD$_{90}$ and V$_{max}$ at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NSCL and SCL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between cardiovascular effects of two preparations.s.

• Journal of the Korean Society of Radiology
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• v.83 no.2
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• pp.444-449
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• 2022

Most cardiac tumors are metastases, and primary cardiac tumors are rare; even among primary cardiac tumors, primary cardiac neuroendocrine tumors (NETs) are extremely rare. Herein, we report a case of a patient presenting a left atrial mass without past medical history. Because of the location and movement of the mass, as well as the patient's cerebral infarction episode, the mass was initially suspected to be a thrombus. However, the mass was surgically diagnosed as NET.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.497-503
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• 2001

Evidence from the last 10 years have been suggested that melatonin mainly produce a depressant effect on the cardiac system, but we found an activating effect of melatonin on heart rate in this research. To determine the hypothesis that melatonin has dual effects on physiological behaviour of cardiac system, we investigated the effects of melatonin on heart rate in isolated rat atria and anesthetized rats. Regardless of concentration, melatonin produced bradycardia in the 84 cases of 148 experiments (57 %) and tachycardia in the 64 cases of 148 experiments (43 %). And in atrium, melatonin produced a decrease automaticity in 52 cases of 86 experiments (60 %) and increase automaticity in 40 % (34/86 cases). Also, these effects are not significnat relationship with concetration of melatonin. The melatonin-induced bradycardia in vivo was inhibited by pretreatment of atropine or bilateral cervical vagotomy. Also, in isolated atrium the melatonin-induced decrease in automaticity was inhibited by pretreatment of atropine. These melatonin-induced responses were potenitated by pretreatment of propranolol. The melatonin-induced tachycardia in vivo was inhibited by pretreatment of propranolol, nifedipine or bilateral cervical vagotomy, but not by pretreatment of atropine. The melatonin-induced incease in automaticity in isolated atrium was converted to decrease in automaticity by pretreatment of propranolol. In addition, the change in heart rate caused by adrenoceptor agonists was inhibited by pretreatment of melatonin. These results indicate that melatonin-induced bradycardia may be related to a muscarinic receptor activation and melatonin-induced tachycardia may be related to a $\beta$-adrenoceptor stimulation.

• The Korean Journal of Pharmacology
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• v.16 no.1 s.26
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• pp.41-50
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• 1980

Chenodeoxycholic acid(CDCA) has been used as a gallstone dissolving agent since 1972. Recently, ursodeoxycholic acid(UDCA) has been reported to be effective in dissolving gallstones. Both bile acids increased bile flow. The increase in bile flow associated with an increase in cholesterol level in bile after CDCA or UDCA infusion was reported. In this study, using the smooth muscle strips of guinea pig and fowl, responses of the cholates were observed. In addition, the influence of adrenergic blocking agents on the response of the strips to cholates was investigated. Also the effects of cholates on cardiac function were examined by using isolated atria of rabbit and heart of anesthetized frog. The results are as follows: 1) All cholates, such as UDCA, CDCA, and CA produced a marked inhibitory effect on the motility in isolated duodenal strip of guinea pig and fowl, however, only UDCA showed the contraction in the isolated esophagus of fowl. These effects of cholates were blocked by propranolol. 2) In isolated guinea pig stomach strip and gall bladder, cholates exhibited a marked inhibitory effect on the motility and the effects due to UDCA and CA were blocked by phenoxybenzamine while CDCA was not affected. 3) The spontaneous and ouabain induced arrhythmia was partially abolished by cholates. However, concomitant administration of cholates with ouabain or epinephrine caused a marked prolongation in occurrence of atrial arrhythmia in comparison with ouabain or epinephrine alone in isolated rabbit atria. 4) In the heart of anesthetized frog, the epinephrine-induced arrhythmia was partially abolished by cholates. The combined treatment with cholates and ouabain or epinephrine produced a marked prolongation in occurrence of the arrhythmia in comparison with, ouabain or epinephrine alone. From the above results, it can be suggested that the effects of cholates on the smooth muscle of duodenum and esophagus are produced in response to adrenergic ${\beta}$-receptor and the effect or gall bladder and stomach is more likely due to the direct effect on the muscle. In addition, cholates exhibit a slight antiarrhythmic effect on heart, therefore, cholates can be classified as a nonselective antiarrhythmic drug, such as propranolol.

• Korean Journal of Clinical Pharmacy
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• v.21 no.1
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• pp.6-13
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• 2011

Bolus intravenous injection of adenosine resulted the temporal decrease of systemic blood pressure and heart rate in the anesthetized rats. Adenosine also resulted the persistent decrease of contractility and heart rate in the isolated spontaneously beating rat right atria. Both of the above inhibition effets of adenosine were increased by the pretreatment of NBI (nitrobenzylthioinosine), whitch is an adenosine transport inhibitor, but decreased by the pretreatment of 8- phenyltheophy1line, which is an adenosine antagonist. In isolated thoracic aorta ring segment of normotensive rats, intact rings were relaxed by adenosine ($42.3{\pm}8.7%$) and ATP ($85.9{\pm}15.8%$) in the concentration of $10^{-4}M$, but rubbed rings were relaxed by adenosine ($35.2{\pm}1.9%$) and ATP ($11.3{\pm}9.0%$) in $10^{-4}M$. After pretreatment of L-NAME (N-Nitro-Larginine methyl ester), which is an NO inhibitor, adenosine-induced relaxation was not affected, but ATP-induced relax ation was significantly inhibited (P<0.01). Meanwhile, adenosine resulted almost same as vasorelaxation in isolated thoracic aorta of SHR comparing to those of normotensive rats. But, vasodilation responses of ATP in intact rings of SHR are significantly inhibited comparing to those of normotensive rats. Adenosine-induced relaxation is attenuated after 8-phenyltheophylline pretreatment, but increased after NBI pretreatment. However, ATP-induced relaxations are not affected by 8-phenyltheophylline or NBI pretreatment. These results suggested that the hypotensive effects of adenosine was due to the decrease of contractile force and heart rate through the A1 receptor and vasodilation are mediated by A2 receptor of the vascular smooth muscle. And, the heart protective and vasodilation effects of adenosine might suggest that it would be useful in the acute treatment of coronary artery disease.