• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.339-347
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• 2009

Purpose : This study was to investigate the influence of heart rate and coronary calcification on diagnostic accuracy of 64-slice multidetector CT(MDCT) in coronary artery disease. Methods : 178 patients(84 men, 94 women) undergoing cardiac CT were included in this study. 3 coronary arteries(LAD, LCX, RCA) were assessed the presence of significant stenosis($\geq50%$) and the results compared with those of coronary angiography. Results : On a patient-based analysis, the diagnostic accuracy of 64-slice MDCT was 96.6%. The diagnostic accuracy on left anterior descending, left circumflex, right coronary artery were 86.5%, 84.3%, 92.1% respectively. Body mass index and blood pressure were not influenced on diagnostic accuracy of 64-slice MDCT. In less than 60/min of heart rate, accuracy was 90.1% and $\kappa$ value was 0.78. While in more than 70/min of heart rate, accuracy was 75.8% and $\kappa$ value was 0.52. In less than 100 of coronary calcification, accuracy was 91.3% and $\kappa$ value was 0.81. While in more than 400, accuracy was 68.6% and $\kappa$ value was 0.33. Conclusion : 64-slice MDCT shows similar diagnostic accuracy as coronary angiography. But in the context of more than 70/min of heart rate and 400 of coronary calcification, diagnostic accuracy was decreased. So there needs to identify heart rate and coronary calcification in cardiac CT, and if heart rate shows more than 70/min, use beta-blocker to regulate it.

• Physical Therapy Korea
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• v.10 no.4
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• pp.69-76
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• 2003

본 연구는 급성기가 지난 뇌졸중 환자를 위한 치료적 운동 프로그램이 심박동수에 미치는 영향과 부가적으로 뇌졸중 환자의 기능적 상태에 따라 치료적 운동 형태를 알아보기 위해서 시행되었다. 대상자는 뇌졸중이 발생한지 3개월이 지난 23명의 환자이었다. 심박동수의 변화는 대상자가 각자의 치료적 운동을 수행하는 동안 Polar Vantage XL Heart Rate Monitor를 사용하여 측정하였다. 그 결과, 치료적 운동 동안 환자의 기능 수준 및 발병 기간에 따른 심박동수와 치료 형태의 차이는 없었다. 또한 전체 치료 시간 중 목표심박동수에 도달하는 시간은 2.47%에 불과하였다. 이는 치료적 운동이 뇌졸중 환자에게 과도한 심혈관 부담을 주지 않을 뿐만 아니라 유산소 훈련의 효과는 거의 존재하지 않음을 의미한다. 따라서 환자의 상태에 적절하고 유산소 훈련 효과를 고려한 치료적 운동 프로그램의 구성이 필요하다.

• Journal of radiological science and technology
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• v.37 no.4
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• pp.307-313
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• 2014

The purpose of this study is that in coronary artery angiography computed tomography (coronary CTA), to gain high quality of image and to use low dose radiation by administrating normal saline and converting the mode of scanning heart rate (HR) characteristics before infusing contrast media. All patients data (total specimens: 200, male: 108, female: 92) were measured by using appropriate mode of scanning the heart rate (HR) after injection of saline. in addition we measured radiation dose (CTDIvol, effective dose) in all examinations. CT number and noise, and blurring of coronary artery (proximal RCA, middle RCA, proximal LCA) were measured and compared. The result of this study after injection of saline, mean heart rate was decreased about $4.8{\pm}0.3bpm$ (beats per minute). 33 patients (13%) got converting scan mode due to reducing heart rate (HR). In prospective gating mode, radiation dose were measured less $6.0{\pm}1.0mSv$ (54.1%) than retrospective gating mode. Also showed a significant difference in heart rate decrease in image evaluation.

• Journal of the Korean Society of Radiology
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• v.12 no.3
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• pp.321-328
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• 2018

The purpose of this study was to investigate factors affecting the heart rate, to analyze the relevance and to use it as a management index of factors of increase in heart rate. A total of 204 adults from November, 2016 to March, 2017 who responded to a personal questionnaire among the adults who underwent coronary computed tomography scans for health screening, were the target of the investigation. In the study, there was a statistically significant difference (p <.05) between the heart rate and the gender, CACS, Stenosis and the forces affecting cardiovascular disease. CACS, Stenosis had a statistically significant difference (p <.05) compared with the other groups in the group with a heart rate of 80 bpm or more, the ability to influence cardiovascular disease was different from that of other groups There was a meaning difference in the heart rate below 60 bpm group compared (p <.05). In conclusion, it is important and desirable to maintain heart rate below 60 bpm in order to prevent having cardiovascular disease history, and below 80 bpm to prevent CACS and stenosis.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.250-257
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• 2010

This study was to analysis what factors could affect left ventricle ejection fraction(LVEF) using 64-slice multidetector CT. 164 patients(84 men, 80 women) had a cardiac CT in this study, and their blood pressure, body mass index(BMI), heart rate(HR) measured. LVEF was 52.00${\pm}$18.95% in below 25kg/$m^2$, 59.50${\pm}$16.05% in above 25kg/$m^2$ of BMI. LVEF was 57.26${\pm}$17.84% in normal blood pressure group(NBPG), 49.95${\pm}$17.63 in hypertension group(HG). LVEF was 60.76${\pm}$17.26 in below 60 beats/min, 54.14${\pm}$16.56 in 60-70 beats/min, 50.83${\pm}$20.56 in above 70 beats/min of HR. LVEF was negatively correlated with age, HR(r=-0.283 p<0.05, r=-0.231 p<0.05. respectively). And LVEF was positively correlated with BMI(r=0.228 p<0.05). A measurement of LVEF at cardiac CT by using MDCT may be considered to age, blood pressure, heart rate and BMI.

• The Korean Journal of Physiology
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• v.21 no.2
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• pp.201-210
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• 1987

수온변화에 따른 심맥관계 및 신장기능의 변화와 생체실험을 통한 온도에 의한 adrenoceptor의 변형을 알아보기 위해, 무마취 자라에서 $18^{\circ}C$에서 $25^{\circ}C$로 수온을 증가시 나타나는 혈압, 심박동수 및 신장기능의 변화를 관찰하고, epinephrine 1 ug/kg과 10 ug/kg을 상이한 온도에 노출된 자라의 정맥내 투여하여 나타나는 효과를 비교하였다. 1) $18^{\circ}C$에서 $25^{\circ}C$로 수온을 증가시킴에 따라 심박동수는 현저히 증가하여 일정하게 유지되었으나, 혈압 및 혈장 renin 활성도는 변화하지 않았다. 온도증가에 의해 뇨량, 사구체여과율 및 전해질 배설량의 현저한 증가를 보였으나 90분부터는 서서히 감소하기 시작하였다. 2) 수온 $18^{\circ}C$에 노출된 자라에서 epinephrine은 dose-dependent한 양상으로 혈압 및 심박동수를 증가시켰으며, 다량의 epinephrine 투여시 작용시간은 현저히 연장되어 있었다. $25^{\circ}C$에 노출된 자라에서는 epinephrine에 의한 혈압상승 효과 및 심박동수 증가는 나타났으나, dose dependency나 작용시간의 차이는 발견할 수 없었다. 3) 동량의 epinephrine에 의한 혈압 및 심박동수의 증가효과는 $18^{\circ}C$와 $25^{\circ}C$에 노출된 자라에서 유의한 차이를 발견할 수 없었으나, $18^{\circ}C$에 노출된 자라에서 epinephrine의 작용시간 및 반감기가 현저히 연장되어 있었다. 4) Epinephrine 투여에 의해 뇨량, 사구체여과율 및 전해질 배설량의 증가를 관찰하였으며, 이는 dose-dependent 양상이었다. 그러나, 신장효과의 유의한 차이는 상이한 온도에 노출된 두 군에서 발견할 수 없었다. 이상의 결과로, 온도증가에 의한 이뇨 및 sodium 배설효과는 혈관이완에 의한 사구체여과율의 증가에 기인한 것으로 사료되며, 상이한 온도에 노출된 자라에서 epinephrine 효과의 차이를 발견할 수 없었던 것은 본 실험에서 가한 좁은 범위의 온도의 변화 내에서는 adrenoceptor의 변형이 나타나지 않을 것이라고 추론하였다. 그러나 저온에서의 epinephrine의 작용시간의 연장은 아마도 epinephrine의 파괴 효소의 활성도의 감소인 것으로 사료된다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.3
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• pp.71-78
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• 2009

In this study, estimation of heart rate from measured PPG signal is proposed. PPG signal is to be measured blood flow in a blood vessel effected by systole and diastole. PPG sianl has single frequency so that PPG frequency can be tracked by 2nd IIR adaptive notch filter. PPG frequency is obtained continually from updating filter coefficient throughout adaptive algorithm and then the heart rate of human is approximately estimated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.765-773
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• 2018

The purpose of this study was to investigate the effect of Healing Beat on autonomic balance, heart rate, and anxiety in healthy adults exposed to stressors. Data were collected from 64 healthy volunteers who volunteered after responded to a recruitment announcement at D City University and analyzed using descriptive statistics, the X2-test, the t-test, and repeated measures of ANOVA. Results showed that both experimental and control general characteristics and variables were homogeneous. Significant intergroup differences were obtained for autonomic balance (F = 6.151, p <.001), heart rate (F = 5.455, p <.001), and anxiety (t = -7.633, p <.001). These results indicate Healing Beat is effective at relieving anxiety in stressful situations, and that Healing Beat can be used to relieve stress in many clinical situations or daily life when individuals are exposed to various stressors.

• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.1-11
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• 1989

In this study, it was aimed to investigate the role of serotonergic neurotransmission in nucleus tractus solitarius (NTS) for the central regulation of blood pressure and heart rate and its involvement in baroreceptor reflex activation in rats. A microinjection of 5-hydroxytryptamine (5-HT) into the NTS produced decreases in blood pressure and heart rate. Maximal decreases were $34.4{\pm}1.6$ mmHg and $41.7{\pm}10.2$ beats per min by 300 pmol of 5-HT. Microinjections of ${\alpha}-methylnor-adrenaline$ $({\alpha}-MNE)$ and clonidine manifested similar decreases in blood pressure and heart rate. The hypotensive and bradycardial effects of 5-HT were blocked by previous applications of 5-HT antagonists, ritanserin, methysergide and ketanserin into the NTS, respectively. By pretreatment with reserpine and 6-hydroxydopamine (6-OHDA, i.c.v.), both hypotensive and bradycardial effects of 5-HT were significantly attenuated. Pretreatment with 5, 7-dihydroxytryptamine (5,7-DHT, i.c.v.) enhanced the hypotensive and bradycardial effects of 5-HT. Similarly, following pretreatment with 6-OHDA, the effects of clonidine were increased. Pretreatment either with 5,7-DHT or 6-OHDA significantly attenuated the sensitivity of baroreflex produced either by phenylephrine or by sodium nitroprusside. When either 5,7-DHT or 6-OHDA was injected into the NTS $(5,7-DHT;\;8{\mu}g\;6-OHDA;\;10{\mu}g)$, both of the baroreflex sensitivities were impaired. In the immunohistochemical study, the injection of 6-OHDA into the the NTS led to reduction of axon terminal varicosity, however, the injection did not reduce the numbers of catecholaminergic cell bodies. Likewise, when 5,7-DHT was injected into the NTS, the varicosity of serotonergic axon terminals was markedly reduced. Based on these results, it is suggested that (1) stimulation of serotonergic receptors in the NTS leads to decreases in blood pressure and heart rate as observed with the stimulation of catecholaminergic system, (2) both serotonergic and catecholaminergic receptors may be located postsynaptically, and (3) the serotonergic neurons as well as catecholaminergic neurons may have a close relevance for the activation of baroreflex.

• Korean Journal of Psychosomatic Medicine
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• v.14 no.1
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• pp.33-38
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• 2006

Biofeedback training to increase the amplitude of respiratory sinus arrhythmia(RSA) maximally increases the amplitude of heart rate variability(HRV) only in respiratory rate at approximately 0.1Hz. To perform this task, people slow their breathing to this rate to point where resonance occur between respiratory sinus arrhythmia(RSA) and oscillation that naturally occur at this rate, probably triggered in part by baroreflex activity. The biofeedback technique allows each individual to breathe at a rate that is specifically adapted to the rhythms of his or her own body. A manual is presented for carrying out this method.