• Biomolecules & Therapeutics
• /
• v.14 no.1
• /
• pp.19-24
• /
• 2006

Atrial chambers serve as mechanosensory systems during the haemodynamic or mechanical disturbances, which initiates arrhythmia. Atrial myocytes, lacking t-tubules, have two functionally separate sarcoplasmic reticulums (SRs): those at the periphery close to the surface membrane, and those at the cell interior (center) not associated with the membrane. To explore possible role of fluid pressure (FP) in the regulation of atrial local $Ca^{2+}$ signaling we investigated the effect of FP on subcellular $Ca^{2+}$ signals in isolated rat atrial myocytes using confocal microscopy. FP was applied to whole area of single myocyte with pressurized automatic micro-jet (200-400 $mmH_2O$) positioned close to the cell. Application of FP enhanced spontaneous occurrences of peripheral and central $Ca^{2+}$ sparks with larger effects on the peripheral release sites. Unitary properties of single sparks were not altered by FP. Exposure to higher FP often triggered longitudinal $Ca^{2+}$ wave. These results suggest that fluid pressure may directly alter excitability of atrial myocytes by activating $Ca^{2+}$-dependent ionic conductance in the peripheral membrane and by enhancing spontaneous activation of central myofilaments.

• Journal of Korean Neurosurgical Society
• /
• v.53 no.6
• /
• pp.368-370
• /
• 2013

Post-stroke atrial fibrillation has been frequently reported especially in the patients with right insular infarct as an evidence of cerebrogenic mechanism affecting on cardiac rhythm. However, conversion to normal sinus rhythm after stroke in patients who had atrial fibrillation has not been reported. A 88-year-old men who had untreated atrial fibrillation was admitted to hospital due to left middle cerebral artery territory infarction. During admission, second ischemic attack occurred in right middle cerebral artery territory. At that time, his atrial fibrillation converted spontaneously to normal sinus rhythm. Restored sinus rhythm sustained until he died due to sepsis. This case is evidence supporting a theory that brain is associated with control of cardiac rhythm. If no risk factor is revealed by intensive investigation in patients with acute cerebral infarctions that cardioembolism is strongly suspected as a cause, physicians should concern transformation of atrial fibrillation to normal sinus rhythm after stroke.

• Journal of Chest Surgery
• /
• v.17 no.1
• /
• pp.74-77
• /
• 1984

Left ventricular-Right atrial canal is a rare congenital heart disease. The vast majority of the cases reported in the literature are clinically diagnosed as atrial septal defect or ventricular septal defect. The method of choice in establishing the diagnosis of left ventricular-right atrlal canal is selective left ventriculography. Recently we experienced one case of left ventricular-right atrial canal which was diagnosed as ventricular septal defect preoperatively. The type of defect was tricuspid perforation of infravalvular type, and repaired with direct suture. Postoperative course was uneventful and discharged without complication.

• Journal of Chest Surgery
• /
• v.20 no.2
• /
• pp.427-431
• /
• 1987

A case is presented of a steering wheel Injury to the chest which developed right atrial free wall rupture and cardiac tamponade without rib fractures or hemo-pneumothorax. A 30 year old man who sustained, blunt chest trauma by steering wheel injury to his chest developed right atrial rupture and cardiac tamponade. Pericardiocentesis was performed and cardiac tamponade was confirmed. After a median sternotomy, large right atrial free wall laceration [about 8cm] was noted. He was placed on cardiopulmonary bypass. The laceration wound of right atrium was closed with a 2 rows of continuous suture. Recovery was uneventful. The patient has returned to his previous level of activity.

• Journal of Chest Surgery
• /
• v.21 no.1
• /
• pp.131-135
• /
• 1988

Primary cardiac tumors usually are benign and are left atrial myxoma. We experienced with two cases of left atrial myxoma recently, and underwent surgical resection successfully. Diagnoses were obtained by echocardiogram and the angiocardiography was not performed. The operation consisted of excision of the tumor with a segment of atrial septum or wall through a right atriotomy, transseptal approach. Postoperative functional results were good and the literature is reviewed.

• Journal of Korean Neurosurgical Society
• /
• v.41 no.6
• /
• pp.429-431
• /
• 2007

Although the ventriculo-peritoneal shunt is the treatment of choice when hydrocephalus should be corrected, the ventriculo-atrial shunt still holds strong alternative when the peritonium is precluded due to the several reasons. During the ventriculo-atrial shunt operation, it is not always easy to dissect and find the corresponding venous structures. In this technical note, the author describes a simple method of percutaneous insertion for placement of the atrial end.

• Journal of Chest Surgery
• /
• v.10 no.2
• /
• pp.230-240
• /
• 1977

Atrial septal defect is one of the most frequently encountered congenital heart disease. Up to December 31, 1976, 1682 cardiac patients received cardiac catheterization in the cardiac department of Yonsei university medical college. Out of the 1682 cardiac patients 723 cases had congenital heart disease and only 116 cases had congetial atrial septal defect. This amounted to 16.04% of all those with congenital heart disease. 58 cases of congenital atrial septal defect operated in the chest surgery department were presented. Of these 58 cases of atrial septal defect, 27 cases were male and 31 cases were female. Their ages ranged from 5 years to 54 years. The systolic pressure of the main pulmonary artery of 40 out of the 58 cases of atrial septal defect was below 40% of that of the systemic blood pressure: in 6 cases, the range of the systolic pressure of the main pulmonary artery was 50-90mmHg; in 12 cases, the range of the systolic pressure of the main pulmonary artery was 40-50mmHg. Average age of these was 30. 1 years. This study tends to show that Korean patients with atrial septal defect even though younger have a slight higher systolic pressure of the main pulmonary artery than Western patients have. The pulmonary blood is 1.5-2.5 times of systemic blood flow in 52 cases out of 58 cases of atrial septal defect.In only one of the 58 cases of atrial septal defect, the Rp was found to be as high as 45% of Rs. All other cases were below this level.51 cases had ostium secundum defect, 4 out of these cases had ostium secundum defect combined with mitral incompetence and 6 out of them had double ostium secundum defect. The remaining 7 cases had ostium primum defect. Their atrial defects were repaired under direct vision utilizing extracorporeal circulation, by hemodilution technic combined with moderate hypothermia. 44 cases [2nd atrial septal defect] were repaired by direct sutures while 14 cases, including the 7 cases ostium primum defects needed patches [1 pericardium and 13 teflon patch]. In 4 cases there were single defects while showed two defects. However the associated septal defect was so small that it could be closed by direct sutures. The size of the defect ranged between 6.0cm2and 10.0cm2 in 19 cases[33.7%]: the smallest being 0. 5cm2 and the largest 24cm2. The surgical mortality was 2 cases [3.4%]. These one case with ostium primum defect, could not be resuscitated on operation table. The cause of death in this case was myocardial failure and MI. The other, a case of ostium primum defect had a second operation on the first operative day due to massive bleeding from LV vent-line insertion site.The patient died on 26th post-operative day due to sepsis.

• The Korean Journal of Physiology and Pharmacology
• /
• v.1 no.1
• /
• pp.79-82
• /
• 1997

The present study was aimed to explore an interaction between endothelium-derived nitric oxide (NO) and atrial natriuretic peptide (ANP) systems in normotensive and hypertensive states. Rats were made two-kidney, one clip (2K1C) hypertensive and supplemented with either $N^G-nitro-L-arginine$ methyl ester (L-NAME, 5 mg/100 ml drinking water) or L-arginine hydrochloride (400 mg/100 ml drinking water). One group supplied with normal tap water served as control. Sham-clipped rats were also divided into the L-NAME, L-arginine, and control groups. The plasma levels and atrial contents of ANP were determined at day 28 following clipping the renal artery. In 2K1C rats, the plasma level of ANP was higher and the atrial content was lower than in the sham-clipped control. L-Arginine increased the atrial content of ANP in association with a decreased plasma ANP, whereas L-NAME significantly affected neither parameter. The increase of blood pressure in 2K1C rats was not affected by L-arginine or L-NAME. In sham-clipped rats, the plasma level of ANP was significantly increased by L-NAME along with an increase in blood pressure. On the contrary, L-arginine did not affect the blood pressure or plasma ANP. The atrial content of ANP was significantly altered neither by L-arginine nor by L-NAME. These results suggest that NO plays a tonic inhibitory role on the ANP release with concomitant increases of the atrial tissue content. In addition, hypertension is suggested to modify the release and tissue storage of ANP.

• Journal of Chest Surgery
• /
• v.32 no.10
• /
• pp.903-909
• /
• 1999

Background: The current study was undertaken to investigate the results of a modification in the conventional Maze III Procedure devised by the authors. The aim of the technical modification was in improving the left atrial contractility. Material and Method: Between July 1997 and December 1998, 34 patients with chronic atrial fibrillation for more than 1 year duration underwent a modified Maze III procedure. The assessment of the left atrial function was made by various echocardiographic measurements and SA nodal recovery was evaluated by HRV Holter monitoring. Result: All 34 patients were in sinus rhythm. On echocardiography, right atrial contraction was detected in 32 patients(94.1%) and left atrial contraction in 33 patients(97.1%). The echocardiographic A wave at 1, 6, and 12 months or more were 50.5$\pm$31.5, 62.1$\pm$25.1, 66$\pm$20.6 cm/sec, respectively, and the E wave measurements at the same time points were 152$\pm$31.1, 134.4$\pm$35.2, 133$\pm$27.5 cm/sec. The corresponding A/E ratios were 0.32$\pm$0.13, 0.48$\pm$0.18, 0.5$\pm$0.15, showing a rising trend. Treadmill evaluation at 6 months showed a mean 82% increase in heart rate after excising, and the SDNN and SDANN upon HRV Holter at 1 and 3 months postoperatively were 65.3$\pm$28.1/87.8$\pm$27.2 ms, and 60.0$\pm$24.1/83.4$\pm$25.7 ms, respectively, showing a predoinant autonomic recovery in the parasympathetic system(PSDNN = 0.01, PSDANN =0.015). Conclusion: The results of our data suggest that the current modification in the conventional Maze III Procedure was efective in enhancing the postoperative left atrial contractility.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.5
• /
• pp.1047-1054
• /
• 2012

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice, and its risk increases with age. Conventionally, the way of detecting AF was the time·frequency domain analysis of RR variability. However, the detection of ECG signal is difficult because of the low amplitude of the P wave and the corruption by the noise. Also, the time·frequency domain analysis of RR variability has disadvantage to get the details of irregular RR interval rhythm. In this study, we describe an atrial fibrillation pattern analysis based on symbolization and information entropy. We transformed RR interval data into symbolic sequence through differential partition, analyzed RR interval pattern, quantified the complexity through Shannon entropy and detected atrial fibrillation. The detection algorithm was tested using the threshold between 10ms and 100ms on two databases, namely the MIT-BIH Atrial Fibrillation Database.