Improvement in Left Ventricular Systolic Dyssynchrony in Hypertensive Patients After Treatment of Hypertension

배병석,김기주,박정길,정연수,류한준,강현재,이봉렬,정병천 대한심장학회 2011 Korean Circulation Journal Vol.41 No.1

Background and Objectives: Left ventricular (LV) dyssynchrony has been commonly detected among hypertensive patients with normal LV systolic function and no evidence of congestive heart failure. The purpose of our study was to assess the changes in LV systolic dyssynchrony (SDS_(LV)) among hypertensive patients after antihypertensive treatment, and to determine the relationship between SDS_(LV) and other conventional echocardiographic parameters. Subjects and Methods: Forty one hypertensive patients with normal LV ejection fraction were enrolled. By performing a conventional echocardiographic study, the SDS_(LV) was measured as the time difference between the shortest and longest time of the peak myocardial systolic velocities among 12 segments of the basal and mid-levels of the 3 apical views, and radial dyssynchrony of the basal (RDS_(base)) and mid-levels (RDS_(mid)) measured as the time difference between the earliest and latest peak values on the radial strain curves of each level of the parasternal short-axis views. Results: Compared to baseline after six months of antihypertensive treatment, the SDS_(LV) improved significantly (48.7±37.9 ms vs. 29.5±34.1 ms, p=0.020). Also the RDSbase and RDS_(mid) improved significantly in respect to the baseline values (129.9±136.3 ms vs. 38.8±45.4 ms, p=0.002 and 75.2±63.8 ms vs. 28.2±37.7 ms, respectively, p<0.001). Conclusion: The severity of SDS_(LV) improved with antihypertensive treatment, and was associated with the regression of LV mass. Furthermore, it might precede improvement in the mitral inflow pattern, as assessed by conventional echocardiography, so that early detection of the benefit of antihypertensive treatment may be possible.

수준별 수영 참여자의 동기유형 분석

배병석,정재은,육동원,김지수,김민현 한국스포츠리서치 2005 한국 스포츠 리서치 Vol.16 No.2

The purpose of this study was to examine motivation type of swimmers by competency level. A total of 262 swimmers were composed of 111 beginners, 58 inter-mediates and 93 advancers participated in the study. For the study, duration of participation, frequency of participation and the level of sport performance of participants were set as the independent variable, while motivation type was the dependent variable. The study used analysis methods such as frequency analysis, t-test, one-way ANOVA between the independent and dependent variables. A significant difference was found after conducting an analysis on the difference in motivation type by duration of participation. The analysis on the difference in motivation type by frequency of participation showed that a group that swam three to five times per week recorded higher marks in terms of physical condition and social life factors than that swam two to three times per week. The analysis on the difference in the motivation type by level of sport performance of participants showed a significant difference in development of skills, enjoyment, achievement, physical condition. social life. external ostentation and amotivation factors.

웨이블릿 영역에서 혼합 모델을 사용한 영상 잡음 제거

배병석(Byoung Suk Bae),강문기(Moon Gi Kang) 대한전기학회 2008 정보 및 제어 심포지엄 논문집 Vol.2008 No.1

AWGN(Additive white gaussian noise)에 의해 영상은 자주 훼손되곤 한다. 최근 이를 복원하기위해 웨이블릿(Wavelet) 영역에서의 베이시안(Bayesian) 추정법이 연구되고 있다. 웨이블릿 변환된 영상 신호의 밀도 함수(pdf)는 표족한 첨두와 긴 꼬리(long-tail)를 갖는 경향이 있다. 이러한 사전 밀도 함수(a priori probability density function)를 상황에 적합하게 추정한다면 좋은 성능의 복원 결과를 얻을 수 있다. 빈번이 제안되는 밀도 함수로 가우시안(Gaussian) 분포 함수와 라플라스(Laplace) 분포 함수가 있다. 이들 각각의 모델은 훌륭히 변환 계수들을 모델링하며 나름대로의 장점을 나타낸다. 본 연구에서는 가우시안 분포와 라플라스(Laplace) 분포의 혼합 분포 모델을 밀도 함수로 제안하여, 이 둘의 장점을 종합하였다. 이를 MAP(Maximum a Posteriori) 추정 방법에 적용하여 잡음을 제거 하였다. 그 걸과 기존의 알고리즘에 비해 시각적인 면(Visual aspect) 수치적인 면(PSNR) , 그리고 연산량(Complexity) 측면에서 향상된 결과를 얻었다.

The Relationship Between Chronic Atrial Fibrillation and Reduced Pulmonary Function in Cases of Preserved Left Ventricular Systolic Function

강현재,배병석,김재훈,이봉렬,정병천,장희상 대한심장학회 2009 Korean Circulation Journal Vol.39 No.9

Background and Objectives: The purpose of this study was to investigate the relationship between chronic atrial fibrillation (AF) and reduced pulmonary function. Subjects and Methods: Eighty-six chronic AF patients who were enrolled from annual health examination programs were studied using echocardiography and pulmonary function tests (PFT). Echocardiography and PFT matched for age, gender, and year performed were selected by the control group who had normal sinus rhythms. Patients with ejection fractions <50%, valvular heart disease, or ischemic heart disease were excluded. Results: In the chronic AF patients, the forced expiratory volume at one second (FEV1), FEV1%, and FEV1/forced vital capacity (FVC) were significantly reduced, and the right ventricular systolic pressure was significantly increased. Episodes of heart failure were more frequently associated with the chronic AF patients than the controls. In particular, the FEV1% had the most meaningful relationship to chronic AF after an adjustment for cardiovascular risk factors {p=0.003, Exp (B)=0.978, 95% confidence interval (CI): 0.963-0.993}. Conclusion: Reduced FEV1%, which represents the severity of airway obstruction, was associated with chronic AF, and the greater the pulmonary function impairment, the greater the co-existence with AF and congestive heart failure in those with preserved left ventricular systolic function. Background and Objectives: The purpose of this study was to investigate the relationship between chronic atrial fibrillation (AF) and reduced pulmonary function. Subjects and Methods: Eighty-six chronic AF patients who were enrolled from annual health examination programs were studied using echocardiography and pulmonary function tests (PFT). Echocardiography and PFT matched for age, gender, and year performed were selected by the control group who had normal sinus rhythms. Patients with ejection fractions <50%, valvular heart disease, or ischemic heart disease were excluded. Results: In the chronic AF patients, the forced expiratory volume at one second (FEV1), FEV1%, and FEV1/forced vital capacity (FVC) were significantly reduced, and the right ventricular systolic pressure was significantly increased. Episodes of heart failure were more frequently associated with the chronic AF patients than the controls. In particular, the FEV1% had the most meaningful relationship to chronic AF after an adjustment for cardiovascular risk factors {p=0.003, Exp (B)=0.978, 95% confidence interval (CI): 0.963-0.993}. Conclusion: Reduced FEV1%, which represents the severity of airway obstruction, was associated with chronic AF, and the greater the pulmonary function impairment, the greater the co-existence with AF and congestive heart failure in those with preserved left ventricular systolic function.

Characteristics of Myocardial Deformation and Rotation in Subjects With Diastolic Dysfunction Without Diastolic Heart Failure

장희상,김재훈,배병석,신승민,김기주,박정길,강현재,이봉렬,정병천 대한심장학회 2009 Korean Circulation Journal Vol.39 No.12

Background and Objectives: There have been very few pathophysiologic studies on isolated diastolic dysfunction. We hypothesized that the characteristics of isolated diastolic dysfunction would be located, on the clinical continuum, between those of a normal heart and diastolic heart failure. Subjects and Methods: We enrolled 102 subjects who had no history of overt symptoms of heart failure and who had a left ventricular ejection fraction of more than 50%. They were examined for myocardial deformation and rotation using the two-dimensional speckle tracking image (2D-STI) technique. Results: The circumferential strains and radial strain at the apical level (RSapex) were related to the ratio of the transmitral early peak velocity over the early diastolic mitral annulus velocity (E/E’). After adjustment for age, the RSapex showed a positive relationship with the E/E’ ratio; whereas, the circumferential strains did not. Instead, the circumferential strains demonstrated a significant correlation with age. Basal rotation and left ventricular (LV) torsion were also related to age, but had no relationship with the E/E’ ratio. However, as the E/E’ ratio value increased, systolic mitral annular velocity decreased. Conclusion: Except for the RSapex, LV myocardial deformation and rotation did not vary with the degree of E/E’ ratio elevation when there was no associated diastolic heart failure. Additionally, in clinical situations such as isolated diastolic dysfunction, the advancement of age has a relatively greater influence on characteristics of LV myocardial deformation and rotation rather than on the E/E’ ratio. Background and Objectives: There have been very few pathophysiologic studies on isolated diastolic dysfunction. We hypothesized that the characteristics of isolated diastolic dysfunction would be located, on the clinical continuum, between those of a normal heart and diastolic heart failure. Subjects and Methods: We enrolled 102 subjects who had no history of overt symptoms of heart failure and who had a left ventricular ejection fraction of more than 50%. They were examined for myocardial deformation and rotation using the two-dimensional speckle tracking image (2D-STI) technique. Results: The circumferential strains and radial strain at the apical level (RSapex) were related to the ratio of the transmitral early peak velocity over the early diastolic mitral annulus velocity (E/E’). After adjustment for age, the RSapex showed a positive relationship with the E/E’ ratio; whereas, the circumferential strains did not. Instead, the circumferential strains demonstrated a significant correlation with age. Basal rotation and left ventricular (LV) torsion were also related to age, but had no relationship with the E/E’ ratio. However, as the E/E’ ratio value increased, systolic mitral annular velocity decreased. Conclusion: Except for the RSapex, LV myocardial deformation and rotation did not vary with the degree of E/E’ ratio elevation when there was no associated diastolic heart failure. Additionally, in clinical situations such as isolated diastolic dysfunction, the advancement of age has a relatively greater influence on characteristics of LV myocardial deformation and rotation rather than on the E/E’ ratio.

수준별 수영 참여자의 동기유형 분석

정재은,김민현,배병석,육동원,김지수 한국스포츠리서치 2005 한국 스포츠 리서치 Vol.16 No.2

Age-Related Changes in Left Ventricular Torsion as Assessed by 2-Dimensional Ultrasound Speckle Tracking Imaging

이현직,김봉수,김재훈,장희상,배병석,강현재,이봉렬,정병천 대한심장학회 2008 Korean Circulation Journal Vol.38 No.10

Background and Objectives: The newly developed 2-dimensional ultrasound speckle tracking imaging (2D-STI) has enabled researchers to assess the changes of left ventricular (LV) rotation and torsion. The aims of the present study are to establish normal values and to examine the effect of advancing age on left ventricular torsion. Subjects and Methods: We enrolled 182 healthy persons in this study. After examined the standard clinical echocardiographic parameters, we obtained the degree of the LV rotation at the basal and apical levels of the short axis view with using a customized software program EchoPAC, GE. Results: Among the 182 healthy subjects, 109 healthy subjects were finally included (49 males and 60 females) due to the failure of obtaining reliable rotational patterns (feasibility: 59.8%). The basal and apical peak LV rotations during systole were 8.14±3.55 degrees and 8.48±3.70 degrees, respectively. The basal peak LV rotation and peak LV torsion had a tendency to increase with aging (r=0.277, p=0.004 and r=0.253, p=0.008, respectively). All the values of the basal LV rotation during systole tended to increase with aging. The apical LV rotation had no relationship with aging throughout the entire cardiac cycle. Conclusion: 2D-STI was a feasible methodology to measure the LV rotation. The peak LV torsion during systole shows statistically significant augmentation with advancing age, and this is mainly due to the increased basal LV rotation. Background and Objectives: The newly developed 2-dimensional ultrasound speckle tracking imaging (2D-STI) has enabled researchers to assess the changes of left ventricular (LV) rotation and torsion. The aims of the present study are to establish normal values and to examine the effect of advancing age on left ventricular torsion. Subjects and Methods: We enrolled 182 healthy persons in this study. After examined the standard clinical echocardiographic parameters, we obtained the degree of the LV rotation at the basal and apical levels of the short axis view with using a customized software program EchoPAC, GE. Results: Among the 182 healthy subjects, 109 healthy subjects were finally included (49 males and 60 females) due to the failure of obtaining reliable rotational patterns (feasibility: 59.8%). The basal and apical peak LV rotations during systole were 8.14±3.55 degrees and 8.48±3.70 degrees, respectively. The basal peak LV rotation and peak LV torsion had a tendency to increase with aging (r=0.277, p=0.004 and r=0.253, p=0.008, respectively). All the values of the basal LV rotation during systole tended to increase with aging. The apical LV rotation had no relationship with aging throughout the entire cardiac cycle. Conclusion: 2D-STI was a feasible methodology to measure the LV rotation. The peak LV torsion during systole shows statistically significant augmentation with advancing age, and this is mainly due to the increased basal LV rotation.