• Journal of Chest Surgery
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• v.27 no.5
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• pp.339-344
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• 1994

Sinus node dysfunction is common after orthotopic heart transplantation.Electrophysiologic studies have documented a high incidence [46% to 50%] of impaired sinus node automaticity and sinoatrial conduction in the early posttransplantation period. Sinus node dysfunction persists in over 20 % of patients and leads to prolonged bradyarrythmias, including sinus or nodal bradycardia and sinus arrest.The purpose of this paper was to observe sinus node dysfunction after orthotopic heart transplantation. Ten cardiac recipient dogs were monitored continuously after orthotopic transplantations between unrelated adult mongrel dogs. Crystalloid cardioplegic solution [Choongwoi Cardioplegia

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.219-230
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• 1988

The effect of glycine, structurally the most simple amino acid was investigated on the electrophysiological characteristics of the isolated superfused atrial muscle and sinus node cells of the rabbit heart. Superfusion of the sinus node cell with glycine solution (3, 5 and 8 mM) produced concentration-dependent increments of OS (overshoot potential) and MDP (maximum diastolic potential). Generally action potential amplitude increased as a result of greater increment of OS than that of MDP. The changes in action potential of the sinus node cell peaked in $7{\sim}10{\;}minutes$ after onset of superfusioin. On the contrary to the response to intravenously administered glycine, the rate of spontaneous firing of sinus node cell was invariably increased following superfusion with glycine. Action potential duration manifested as $APD_{60}$ (time to 60% repolarization) was significantly shortened by glycine. And the electrophysiological effects of glycine on the atrial muscle cell were similar to that on the sinus node cells. The results of present study suggest that glycine can exert direct effects on the atrial muscle and sinus node cells of the rabbit heart.

• The Korean Journal of Physiology
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• v.23 no.2
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• pp.339-350
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• 1989

Electrophysiological effects of ammonia was studied in the isolated superfused sinus node and atrial muscle cells of the rabbit heart. No significant changes were observed in the overshoot potential (05), maximum diastolic potential (MDP), and action potential amplitude (APA) of the sinus node cells following superfusion with 3.0 mM ammonia, fifty times upper limit of the normal human plasma level. However the action potential duration (APD) of sinus node cells were significantly prolonged after superfusion with 0.6 mM ammonia for 20 min or with 1.2 and 3.0 mM ammonia for 5 minutes. Ammonia in all the concentrations tested decreased the rate of spontaneous firing (RSF) from the sinus node cells. After superfusion of sinus node cells with 0.3 mM ammonia for 20 min, the RSF significantly decreased from 20 min to 25 min after onset of superfusion while a significant decrement in the RSF was observed from 7 min to 30 min following superfusion with 3.0 mM ammonia for S min. On the other hand, the effects of ammonia on the action potential of the rabbit atrial muscle cell were much similar to those on pacemaker cells except that the atrial cell was generally less sensitive to ammonia. The results suggest that ammonia may cause changes in the action potential of the rabbit cardiac cells by the direct action, and that the cardiac effects of ammonia are generally opposite to those of glycine.

• Applied Microscopy
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• v.20 no.1
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• pp.77-89
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• 1990

The ultrastructures of the hemal node and the hemolymph node in the Korean native goat were observed by transmission and scanning elelctron microscopies for their morphological features. The sinus of hemal node was lined by endothelial-like reticular cells that had an euchromatin-rich nucleus and many cytoplasmic processes by which reticular fibers were surrounded. In the hemolymph node, the mast cell and the plasma cell were closely contact each other by the cytoplasmic process. The hemal node had venous sinusal-like vessels which were different from the deep sinus, and the hemolymph node had lymph capillaries. The lymph vessels with valves were observed in the capsule of the hemolymph node.

• Journal of Chest Surgery
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• v.28 no.6
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• pp.579-582
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• 1995

The extended transseptal approach to the mitral valve replacement has been used for 30 patients. There were 19 women and 11 men. Twenty five patients had rheumatic heart disease, 4 had degenerative valve ,and 1 had valve prolapse. Fifteen of 30 patients had other associated procedure; 10 had aortic valve replacement; 5 had tricuspid annuloplasty. There were no postoperative complications associated with the approaches, ie, no bleeding, no sinus node dysfuction, and no atrioventricular conduction disturbance. Despite division of the sinus node artery, preoperative atrial rhythms[3 sinus rhythms and 27 atrial fibrillations were not changed during postoperative period. The extended transseptal approach provides good mitral valve exposure without inherent complications, and is superior to that of standard approach, so we use it routinely for mitral valve procedure.

• Journal of Chest Surgery
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• v.16 no.2
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• pp.199-212
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• 1983

The inhibition/influences of adenine compounds on the heart have been described repeatedly by many investigators, since the first report by Druny and Szent-Gyorgyi [1929]. These studies have shown that adenosine and adenine nucleotides have an over-all effect similar to that of acetylcholine [ACh] by slowing and weakening the heartbeat. The basic cellular and membrane events underlying the inhibitory action of adenosine on sinus rate, however, are not well understood. Furthermore, the physiological role of adenosine in regulation of the heartbeat remains still to be elucidated. Therefore, this study was undertaken in order to examine the response of rabbit SA node to adenosine and to compare the response to that of ACh. Isolated SA node preparation, whole atrial pair, or left atrlal strip was used in each experiment. Action potentials of SA node were recorded through the intracellular glass microelectrodes, which were filled with 3M KCI and had resistance of 30-50 M. All experiments were performed in a bicarbonate-buffered Tyrode solution which was aerated with 3% $CO_2-97%$ $O_2$ gas mixture and kept at $35^{\circ}C$. Spontaneous firing rate of SA node at 35C [Mean + SEM, n=16] was 154 + 3.3 beats/min. The parameters of action potentials were: maximum astolic potential [MDP], -731.7mV: overshoot [OS], 9 + 1.4mV; slope of pacemaker potential [SPP], 94 3.0mV/sec.Adenosine suppressed the firing rate of SA node in a dose dependent manner. This inhibitory effect appeared at the concentration of $10^{-6}M$ and was potentiated in parallel with the increase in adenosine concentration. Changes in action potential by adenosine were dose-dependent increase of MDP and decrease of SPP until $10^{-4}$. Above this concentration, however, the amplitude of action potential decreased markedly due to the simultaneous decrease of both MDP and OS. All these effects of adenosine were not affected by pretreatment of atropine [2mg/l] and propranolol [$5{\times}10^{-6}M$]. ACh [$10^{-6}M$] responses on action potential were similar to those of adenosine by increasing MDP and decreasing SPP. These effects of ACh disappeared by pretreatment of atropine [2mg/1]. Inhibition/effects of adenosine and ACh on sinus rate were enhanced synergistically with the simultaneous administration of adenosine and ACh. Marked decrease of overshoot potential was the most prominent feature on action potential. Dipyridamole [DPM], which is known to block the adenosine transport across cell membrane, definitely potentiated the action of adenosine . Adenosine suppressed the sinus rate and atrial contractility in the same dosage range, even in the reserpinized preparation. Above` results suggest that adenosine suppresses pacemaker activity, like ACh, by acting directly on the membrane of SA node, increasing MDP and decreasing SPP.

• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.195-197
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• 2003

Sick sinus syndrome(SSS) constitutes a spectrum of cardiac arrhythmia, including sinus bradycardia, sinus pause-arrest, sinoatrial block, slow escape rhythm, bradyarrhythmia and tachyarrhythmia. SSS is relatively uncommon in children but its exact incidence is unknown because diagnostic criteria are not uniform and most children with SSS, in general are asymptomatic. SSS may be primary(organic sinus node disease) or secondary(cardiac surgery comprises much of SSS in children and adolescents), but it can hardly be caused by familial relations as well. We reports an occurrence of familial sick sinus syndrome. Mother was diagnosed as SSS, which was presented by symptoms of dizziness and treated by permanent pacemaker(DDD). Also, two daughters revealed SSS with non-compacted cardiomyopathy on neonatal screening and fetal echocardiography respectively. We concluded that familial SSS may occur, so familial screening should be suggested.

• Korean Journal of Veterinary Service
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• v.46 no.1
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• pp.81-85
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• 2023

This case report is about hemolymph nodes found in a dairy cow whose function is still not fully elucidated. A 4-month Holstein cow presented severe respiratory symptoms and hematochezia for a while with respiratory acidosis and metabolic alkalosis. Coccidiosis was diagnosed and treated immediately, but the cow died from respiratory acidosis and metabolic alkalosis. At necropsy, no abnormal appearance in thoracic and peritoneal organs was observed, but hemolymph nodes were observed being multifocally stuck on omasum serosa and the subcutaneous fascia of abdominal region, and the larger dark red lymph nodes were found along the omasum great curvature. Microscopically, lymphoid depletion and lymphadenitis in the lymph nodes were examined to point systemic infection, and in the hemolymph node, multifocally demarcated pale lesions with macrophage infiltration and fibrin deposition nearby subcapsular sinus. In subcapsular sinus of the hemolymph node, rod to linear gram-negative bacteria were found. Through this study, we might conclude that the hemolymph node is involved in pathogen phagocytosis.

• Journal of Chest Surgery
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• v.28 no.2
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• pp.177-179
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• 1995

Sinus venosus type atrial septal defect is commonly associated with partial anomalous pulmonary venous return[PAPVR . Ideal surgical repair of sinus venosus ASD with PAPVR demands complete closure of septal defect with redirection of the anomalous pulmonary venous return to the left atrium without obstructing the superior vena cava[SVC or the anomalous pulmonary vein and without injury of sinoatrial node and residual shunt. In our two patients, the closure of sinus venosus ASD and correction of PAPVR could be accomplished by simple direct sutures without using a patch or flap. Both patients had a good outcome.

• Journal of the Institute of Convergence Signal Processing
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• v.23 no.2
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• pp.62-69
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• 2022

An electrocardiogram (ECG) is one of the most important biosignals, and in particular, continuous ECG monitoring is very important in patients with arrhythmia. There are many different types of arrhythmia (sinus node, sinus tachycardia, atrial premature beat (APB), and ventricular fibrillation) depending on the cause, and continuous ECG monitoring during daily life is very important for early diagnosis of arrhythmias and setting treatment directions. The ECG signal of arrhythmia patients is very unstable, and it is difficult to detect the R-peak point, which is a key feature for automatic arrhythmias detection. In this study, we develped a continuous measuring Holter ECG monitoring device and software for analysis and confirmed the utility of R-peak of the ECG signal with MIT-BIH arrhythmia database. In future studies, it needs the validation of algorithms and clinical data for morphological classification and prediction of arrhythmias due to various etiologies.