자기장 측정 홀소자 집게형 맥진기를 이용한 허맥과 실맥 예측 알고리즘 개발

이남규(Nam-Kyu Lee),김근호(Keun-Ho Kim),이상석(Sang-Suk Lee),유지혜(Ji-Hye Yu),유준상(Jun-Sang Yu),선승호(Seung-Ho Sun),장세진(Sei Jin Chang),홍유식(Yu-Sik Hong) 한국자기학회 2013 韓國磁氣學會誌 Vol.23 No.3

Clip-type pulsimeter equipped with Hall device and a minute permanent magnet as sensing the minute movement of a radial artery was developed. The clinical data of the 120 number of subject acquisited through the clip-type pulsimeter did treated with a typical statistical logistic regression analysis. The prediction algorithm for the replete pulse and vacuous pulse was studied. The reflective peak time and the notch peak time were major parameters to discern the replete pulse and vacuous pulse. The discrimination rate was 65 %. It suggests that the logistic regression equations are possible to use the diagnosis index to predict and discern the oriental pulse wave.

맥파전달속도를 이용한 내중막 두께 추정에 관한 연구

송상하,장승진,김원식,이현숙,윤영로,Song, Sang-Ha,Jang, Seung-Jin,Kim, Wuon-Shik,Lee, Hyun-Sook,Yoon, Young-Ro 대한의용생체공학회 2009 의공학회지 Vol.30 No.5

In this paper, we correct pulse wave velocity(PWV) with heart-rate and derive regression equations to estimate intima-media thickness(IMT). Widely used methods for diagnosis of arteriosclerosis are IMT and PWV. Arterial wall stiffness determines the degree of energy absorbed by the elastic aorta and its recoil in diastole but there is not correlation between sclerosis and IMT in an existing study. In this study, we will correct PWV with heart-rate and get regression equation to estimate IMT using heart-rate correction index(HCI). We executed experiments for this study. Made up question of physical condition and measured electrocardiogram(ECG), photoplethysmogram (PPG) of finger-tip and toe-tip and ultrasound image of carotid artery. Calculated PWV and IMT using ECG, PPG and ultrasound image. We found that every p-value between PWV and IMT is not significant(<0.05). But p-value between IMT and HCI which is a corrected PWV using heart-rate is significant(>0.01). We use HCI and various measured parameter for estimating regression equation and apply backward estimation to select parameters for regression analysis. Result of backward estimation, found that only HCI is possible to derive proper regression equation of IMT. Relationship between PWV and IMT is the second order. Result of regression equation of E-H PWV is $R^2$=0.735, adj $R^2$=0.711. This is the best correlation value. We calculate error of its analysis for verification of earlobe PWV regression equation. Its result is RMSEP=0.0328, MAPE(%) = 4.7622. Like this regression analysis, we know that HCI is useful parameter and relationship between PWV, HCI and IMT. In addition, we are able to suggest possibility which is that we can get different parameter of prediction throughout just one measurement.

Augmentation Index in Connective Tissue Diseases

( Joon Hyouk Choi ),( Jinseok Kim ) 대한류마티스학회 2017 대한류마티스학회지 Vol.24 No.4

Atherosclerosis and its complications are often reported in patients with connective tissue diseases (CTDs) showing chronic inflammation. Traditional cardiovascular risk factors do not account for accelerated atherosclerosis in patients with CTDs. Inflammation, although non-traditional, is considered one of the risk factors for endothelial dysfunction, atrial stiffness, and atherosclerosis. Therefore, it is essential to evaluate other risk factors for cardiovascular disease (CVD) in patients with CTDs. The interest in pulse wave analysis (PWA) is growing because of its predictive value for CVD. The arterial pressure waveform is a composite of an incidental wave produced by a ventricular contraction and a reflected wave. The wave reflection can be quantified using the augmentation index (AIx); it is defined as the difference between the inflection and peak systolic pressure, and expressed as a percentage of the pulse pressure. The PWA is represented by AIx. Risk score systems, such as the Framingham scoring system, were correlated with AIx. Many studies have analyzed the ability of the AIx to predict the CAD severity in the general population. In patients with CTDs, the AIx was found to increase compared to a healthy control group. The AIx was related to the activity of CTDs. The treatment for inflammation appeared to improve the AIx in some CTDs. Although more studies will be needed to obtain conclusive evidence, AIx is expected to be a prognostic factor or a risk factor for CVD in patients with CTDs. (J Rheum Dis 2017;24:185-191)

Seismic Vulnerability Analysis of Multi-main-span High Pier Continuous Rigid-frame Bridge in Terms of Cloud Method

Jingang Zhao,Hongyu Jia,Yulin Zhan 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.6

Due to the complex canyon topography in southwestern regions of China, several multi-main-span high pier continuous rigid-frame bridges (MHPCRFBs) are built to meet the special terrain. Owing to the great effect of high-order modes, the seismic responses of MHPCRFBs are more complicated than the conventional signal main span continuous rigid-frame bridges. However, there has been very limited researches focus on the seismic vulnerability of MHPCRFBs. This study selects a practical five-span (three main span) high pier continuous rigid-frame bridge as a study object to investigate the seismic vulnerability of MHPCRFBs under near-field pulse-like seismic wave excitation. And a finite element model of the example bridge is built by OpenSees incorporating the influence of abutment, and simultaneously100 near-field pulse-like seismic waves are chosen to research their effect on the seismic vulnerability of the MHPCRFB. The dynamic nonlinear time-history analyses are carried out to record the peak demand values of the example bridge under three seismic excitation calculation cases (longitudinal earthquake, biaxial earthquake, and triaxial earthquake). Thirty-three intensity measures are compared with respect to two statistical parameters including correlation efficient and root mean square error, the peak ground velocity (PGV) turns out to be the optimal intensity measure for seismic vulnerability analysis of MHPCRFB. Subsequently, by using the analysis procedures of the cloud method, the seismic vulnerability curves of MHPCRFB are developed and compared. The results of this study show that the bottom and top areas of the high piers are more fragile at the slight and moderate damage stages along longitudinal direction, and only the bottom areas are prone to damage along transverse direction. And the seismic wave excitation directions have an obvious influence on the seismic damage probability of the MHPCRFB. In addition, the zone with larger failure probabilities of the lower pier is significantly longer than the higher pier. The obtained results provide helpful reference for the seismic-resistant design and consolidation of MHPCRFBs, shed light on the lower pier of MHPCRFBs should be paid high concern to the anti-seismic design.

Arterial stiffness and its associations with left ventricular diastolic function according to heart failure types

김학령,Jaehoon Chung,한석문,Hyun Sung Joh,Woo‑Hyun Lim,Jae‑Bin Seo,Sang‑Hyun Kim,Joo‑Hee Zo,Myung‑A Kim 대한고혈압학회 2023 Clinical Hypertension Vol.29 No.-

Background Little is known about the characteristics of arterial stifness in heart failure (HF). This study was per‑ formed to compare the degree of arterial stifness and its association with left ventricular (LV) diastolic function among three groups: control subjects, patients with HF with reduced ejection fraction (HFrEF), and patients with HF with preserved ejection fraction (HFpEF). Methods A total of 83 patients with HFrEF, 68 patients with HFpEF, and 84 control subjects were analyzed. All HF patients had a history of hospitalization for HF treatment. Brachial-ankle pulse wave velocity (baPWV) measurement and transthoracic echocardiography were performed at the same day in a stable condition. Results The baPWV was signifcantly higher in patients with both HFrEF and HFpEF compared to control subjects (1,661±390, 1,909±466, and 1,477±296 cm/sec, respectively; P<0.05 for each). After adjustment of age, baPWV val‑ ues were similar between patients with HFrEF and HFpEF (P=0.948). In the multiple linear regression analysis, baPWV was signifcantly associated with both septal e′ velocity (β=–0.360, P=0.001) and E/e′ (β=0.344, P=0.001). How‑ ever, baPWV was not associated with either of the diastolic indices in HFrEF group. The baPWV was associated only with septal e′ velocity (β=–0.429, P=0.002) but not with E/e′ in the HFpEF group in the same multivariable analysis. Conclusions Although arterial stifness was increased, its association with LV diastolic function was attenuated in HF patients compared to control subjects. The degree of arterial stifening was similar between HFrEF and HFpEF.

Effect of Subject Posture on Pulse Wave Measurement

Ki Chang Nam,Eun Geun Kim,Hyun Heo,Young Huh 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

In this study, pulse wave parameters change were verified by changing a subject posture. To measure pulse wave in radial artery, noninvasive tonometric pulse wave measurement device (SphygmoCor PX, AtCor, Austrailia) was applied. And 20 parameters of pulse wave for peripheral and central artery were evaluated according to measurement posture; stand, sit and supine. As a result, there were significant differences on P_T1, P_T2, P_T2-T1, ED, PP_AI, PPAmpRatio, HR, SEVR, C_TTI and C_AI (p < 0.05) depend on measurement postures of the subject. Based on this study, for estimating central pulse wave by transfer function from radial pulse measurement, subject posture should be considered in several pulse wave characteristics.

要素分析法에 의한 單位脈狀 해석

박영배(Young-Bae Park) 대한미병의학회 2020 대한미병의학회지 Vol.1 No.1

In order to define the pulse type, the relevant contents were reviewed in literature, and the Elements analysis method for analyzing the pulse type according to the components and the Unit pulse type corresponding to the basic pulse type were proposed. The pulse can be analyzed by 9 elements such as pulse width, pulse shape, pulse depth, pulse length, pulse strength, pulse fluctuation, pulse ratio, pulse rhythm, pulse speed, and it can be interpreted by 20 unit pulse types such as floating-deep, slow-rapid, long-short, big-thin, empty-full, wiry-tight, slippery-choppy, hollow-leather-confined, hasty-knotted-intermittent. In addition, it was found that the combined pulse type composed of various units can be analyzed and expressed through the unit pulse type.

Correlation of Arterial Stiffness and Bone Mineral Density by Measuring Brachial-Ankle Pulse Wave Velocity in Healthy Korean Women

김남이,서희선 대한가정의학회 2015 Korean Journal of Family Medicine Vol.36 No.6

Background: An association between arterial stiffness and osteoporosis has previously been reported. Therefore, we investigated the relationship between arterial stiffness, measured by brachial-ankle pulse wave velocity, and bone mineral density in a sample of healthy women undergoing routine medical checkup. Methods: We retrospectively reviewed the medical charts of 135 women who had visited the Health Promotion Center (between May 2009 and December 2012). Brachial-ankle pulse wave velocity was measured using an automatic wave analyzer. Bone mineral density of the lumbar spine (L1–L4) and femur was measured by dual-energy Xray absorptiometry. Metabolic syndrome was defined according to National Cholesterol Education Program–Adult Treatment Panel III criteria, using body mass index >25 kg/m2 instead of waist circumference >88.9 cm. Results: Pearson’s correlation analysis revealed significant inverse relationships between pulse wave velocity and bone mineral density of the lumbar spine (r=-0.335, P<0.001), femur neck (r=-0.335, P<0.001), and total femur (r=-0.181, P=0.04). Pulse wave velocity showed the strongest association with age (r=0.586, P<0.001). Multiple regression analysis identified an independent relationship between pulse wave velocity and lumbar spine bone mineral density in women after adjusting for age, metabolic syndrome, body mass index, smoking status, alcohol intake, and exercise (r=-0.229, P=0.01). Conclusion: This study confirmed an association between arterial stiffness and bone mineral density in women.

손목의 피부특성을 고려한 맥상파 해석모델 개발

신상훈 ( Sang-hoon Shin ) 대한한의진단학회 2011 大韓韓醫診斷學會誌 Vol.15 No.2

Objectives The purpose of this study is to develop the pulse wave analysis model with the palpation pressure and the skin effect. Methods The position of pulse diagnosis was modeled with elastic string system. The skin was modeled with the elastic string, the palpation pressure with tension in the string, and the blood vessel pressure with external force on the string. Using the wave equation in the physics, the simplified pulse model was transformed to the mathematical model. Results To the verification of the model, the effects of the palpation pressure and the skin effect were tested. Conclusions There was optimal palpation pressure, describing the exact vessel pressure pattern and maximizing the amplitude of the skin displacement. For the optimal condition, the increased palpation pressure was needed with the increased skin thickness. Therefore, the developed pulse wave analysis model showed the good results.

한국 여성의 추적검사에서 동맥 맥파속도 변화에 영향을 주는 인자

김대영,공성열,이성자,송하도,한은진,양지훈,김지연,이동현,신현호 대한고혈압학회 2012 Clinical Hypertension Vol.18 No.4

Background: Pulse Wave Velocity (PWV) correlates well with arterial distensibility and stiffness and is a useful approach for evaluating the severity of systemic arteriosclerosis in adults. In addition, measurement of brachial-ankle PWV (baPWV)has been commonly reported as a simple, noninvasive, and practicable method. Arterial stiffness assessed by PWV could predict cardiovascular morbidity and mortality. In this study, we investigated the association between the changes of baPWV and cardiovascular risk factors in Korean women using data from follow-up evaluations. Methods: The subjects were 626women (age, 47.2 ± 8.2) in whom we measured baPWV and cardiovascular risk factors at baseline and about one year later. Arterial stiffness was evaluated by baPWV and biological parameters were evaluated on the same day. We retrospectively analyzed the relationships between changes of baPWV and those other factors. All analyses were performed with SPSS ver. 20.0 and p-values < 0.05 were considered significant. Results: In correlation analysis, changes of baPWV were affected by changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure, total cholesterol, high density lipoprotein-cholesterol, and low density lipoprotein-cholesterol. Multiple regression analysis of relationship between changes of baPWV and other associated variables shows that improvement of baPWV was significantly positively associated with changes of SBP and hemoglobin A1c (HbA1c), and worsening of baPWV was significantly negatively associated with changes of DBP, age, and SBP in sequence. Conclusions: In improvement of baPWV, decreases of SBP and HbA1c and in worsening of baPWV, increases of DBP, age, and SBP were significant factors in Korean women. 연구배경: 상완-발목 맥파속도(brachial-ankle pulse wave velocity, baPWV)는 동맥 경직도를 수량적으로 측정함으로써, 동맥경화증의 정도를 예측하고 심혈관질환을 예견하는 지표로 사용되고 있다. 동맥 경직도에 영향을 미치는 것으로는 연령, 심혈관계 위험인자 그리고 심혈관계질환, 고혈압 및 당뇨병 가족력 등의 유전적 배경 등 수많은것이 알려져 있고, baPWV에 가장 강력한 영향을 미치는인자로는 나이와 혈압이 알려져 있다. 저자들은 baPWV 를 추적 관찰한 여성들을 대상으로 맥파속도의 변화에 영향을 끼치는 인자들에 대해 알아보고자 하였다. 방법: 관동의대 제일병원 건강증진센터에 내원하여 신체종합검사를 받은 여성 중에서 자동파형분석기를 이용하여 맥파속도를 추적 관찰한 626명을 대상으로 하였다. 신체계측, 수축기 및 이완기혈압, 맥압, 당화혈색소, 공복혈당 및 총 콜레스테롤, 중성지방, 고밀도 및 저밀도지단백 콜레스테롤 등을 약 1.3년 간격으로 측정하여 맥파속도의 변화와 상관관계를 구하였다. 결과: 추적검사를 통해 맥파속도가 좋아진 집단과 나빠진 집단을 감소와 증가 정도에 따라 세분하여서 맥파속도변화에 영향을 미치는 인자들을 조사해 본 결과, 좋아진집단에서는 체중 변화, 수축기와 이완기혈압 변화, 맥압변화, 총 콜레스테롤 변화, 저밀도지단백 콜레스테롤 변화, 당화혈색소 변화와 유의한 연관관계가 있었고, 나빠진 집단에서는 나이 변화, 수축기와 이완기혈압 변화, 맥압 변화, 고밀도지단백 콜레스테롤 변화와 연관성이 있었다. 맥파속도의 변화에 영향을 끼치는 인자들을 독립변수로 하고 맥파속도 변화를 종속변수로 하여 실시한 다중회귀분석결과 좋아진 집단에서는 수축기혈압 변화(β =0.262, p = 0.001), 당화혈색소 변화(β = 0.229, p = 0.001) 의 순서로 의미 있는 상관관계를 보이고, 나빠진 집단에서는 이완기혈압 변화(β = 0.159, p = 0.039), 나이 변화(β= 0.140, p = 0.008), 수축기혈압 변화(β = 0.121, p =0.040)의 순서로 의미 있는 상관관계를 보였다. 결론: 한국 여성에서 baPWV의 향상과 연관성이 있는인자는 순서대로 수축기혈압 감소와 당화혈색소 감소이고, 악화에는 이완기혈압 증가, 나이 증가, 수축기혈압 증가임을 확인할 수 있었다.