OBJECTIVE: This study aimed to determine the efficacy of flexible pole training combined with lumbar stabilization in improving trunk muscle activities and to investigate the difference according to posture in young adults. METHODS: Twenty-five participants were enrolled in this study. The subjects were randomly allocated into either the flexible pole group or the rigid pole group. Participants performed lumbar stabilization exercises on quadruped and curl-up, with the flexible pole or rigid pole. Electromyography was used to assess the percent maximal voluntary isometric contracion (%MVIC) of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spine (ES) muscles. All participants completed one 30-minute session per day, 3 days per week, for 6 weeks. The evaluation was performed before and 6 weeks after the training, and follow-up. The data were analyzed using independent t-test and two-way repeated measure analysis of variance to determine the statistical significance. RESULTS: The flexible pole in curl-up showed significant differences in EO and IO muscle activities compared with the rigid pole. The flexible pole in quadruped showed significant differences in IO and ES muscle activities compared with the rigid pole. The RA, EO, IO, and ES muscle activities of both groups were significantly higher after 6 weeks training. CONCLUSION: The flexible pole in curl-up and quadruped showed an improvement in trunk muscle activation. The flexible pole combined with lumbar stabilization will be useful as an exercise tool to improve activity of trunk muscles.
Adult ; Electromyography ; Exercise ; Follow-Up Studies ; Humans ; Jupiter ; Muscles ; Posture ; Rectus Abdominis ; Spine ; Young Adult

BACKGROUND AND OBJECTIVES: Electrocardiography (ECG) is a cost-effective and useful method for diagnosing left ventricular hypertrophy (LVH) in a large-scale study or in clinical practice. Among ECG criteria, the Cornell product (Cor P) and Sokolow-Lyon criteria were adopted by the European Society of Hypertension-European Society of Cardiology Guidelines but have different performances among races. The aim of this study was to compare the diagnostic performance of two voltage criteria in Korean patients. SUBJECTS AND METHODS: Electrocardiography and echocardiographic LV mass of 332 (159 male, 173 female) consecutive patients were analyzed. Cornell voltage criteria and the Cor P were compared with Sokolow-Lyon voltage (Sok V) and the Sokolow-Lyon product (Sok P). The sensitivities and specificities were estimated using a receiver-operating characteristics (ROC) curve in relation to the LVH diagnosis. The sensitivities and revised cut-off values were derived at specificity levels of 90, 95, and 100%. RESULTS: The Cornell-based criteria generally showed better performance than that of the Sok V criteria and Sok P in the area under the ROC curve analysis. The revised cut-off values for the Cornell voltage criteria (20 and 16 mm for males and females, respectively) showed an improved sensitivity (19.7 and 30.3% for males and females, respectively), with a high specificity of 95%. CONCLUSION: The Cornell-based criteria had better performance than that of the Sokolow-Lyon criteria in both Korean men and women. However, revised cut-off values are needed to improve accuracy.
Cardiology ; Continental Population Groups ; Echocardiography ; Electrocardiography ; Female ; Humans ; Hypertrophy, Left Ventricular ; Male ; ROC Curve ; Sensitivity and Specificity

BACKGROUND: Although the net atrioventricular compliance can be obtained by invasive catheterization (Ccath) in mitral stenosis (MS), feasibility of noninvasive echocardiographic calculation of the compliance (Cecho) and its hemodynamic significance were not tested. METHODS: Using valve area by 2D planimetry (A2D) and deceleration slope (dv/dt) of transmitral velocity decay in continuous wave Doppler echocardiographic tracing, Cecho was defined as -A2D/(gamma dv/dt), which was compared with Ccath obtained directly during the catheterization in 30 MS patients with sinus rhythm. Exercise Doppler echocardiography with symptom-limited treadmill was performed in 66 patients with moderate to tight MS: mean mitral gradient (MG) and peak pressure gradient of tricuspid regurgitation (PGTR) at baseline and immediately after exercise were obtained using continuous wave Doppler echocardiographic tracing. Hemodynamic variables including Cecho, MG, PGTR and mitral valve area were analyzed to determine the association with patients' exercise tolerance. RESULTS: Cecho in 30 patients with tight MS (valve area 0.9+/-0.2 cm 2) was 4+/-1 ml/mmHg (2-7 mmHg), which showed a significant correlation with Ccath (r=0.48, p=0.01). Exercise time in 66 patients with moderate to tight MS showed significant negative correlation with resting MG, resting and postexercise PGTR, and positive correlation with Cecho: exercise time in those patients did not show any significant correlation with resting valve area. In multivariate analysis, Cecho and postexercise PGTR were independent factors determining exercise time in MS. CONCLUSIONS: The net atrioventricular compliance in MS can be calculated by noninvasive echocardiography, and it is an important hemodynamic factor determining exercise tolerance in MS.
Catheterization ; Catheters ; Compliance ; Deceleration ; Echocardiography ; Echocardiography, Doppler ; Exercise Tolerance ; Hemodynamics ; Humans ; Mitral Valve ; Mitral Valve Stenosis ; Multivariate Analysis ; Tricuspid Valve Insufficiency

PURPOSE: Although the quality of life (QoL) of prostate cancer (PCa) patients is a major issue, there is no unified and useful methodology for assessing QoL. The Expanded Prostate Cancer Index Composite (EPIC) is a globally used tool to measure QoL after PCa treatment that comprises urinary, bowel, sexual, and hormonal domains. Acknowledging the need for such a tool applicable to Korean PCa patients, we translated EPIC into Korean and validated the new version. MATERIALS AND METHODS: The Korean version of EPIC was devised by translation, back-translation, and reconciliation. Subsequently, we randomly selected 153 patients with localized PCa treated with radical perineal prostatectomy (67, 43.8%), radical retropubic prostatectomy (19, 12.4%), laparoscopic radical prostatectomy (12, 7.8%), robot-assisted laparoscopic radical prostatectomy (36, 23.5%), and high-intensity focused ultrasound ablation of the prostate (19, 12.4%) and asked them to complete EPIC. Reliability was assessed by test-retest correlation and Cronbach's alpha. Validity was assessed by factor analysis, interscale correlation, and correlation with Functional Assessment of Cancer Therapy-Prostate (FACT-P). RESULTS: Test-retest correlation and Cronbach's alpha were high in each of the domains (0.92, 0.91, 0.76, 0.84 and 0.86, 0.84, 0.92, 0.83, p<0.0001). Interscale correlation among the domains was low (r<0.37), which indicated that EPIC is composed of proper domains. Interscale correlation between the function and bother subscales was high (0.94, 0.81, 0.84 and 0.80, p<0.0001). EPIC domains had low correlation with FACT-P, permitting complementary use. CONCLUSIONS: The Korean version of EPIC was developed by a proper process, as evident by its high reliability and validity. Therefore, it is a reliable, comprehensive, systematic method that evaluates QoL in Korean patients after PCa treatment. Furthermore, it can be adapted as an objective methodology for research globally.
High-Intensity Focused Ultrasound Ablation ; Humans ; Passive Cutaneous Anaphylaxis ; Prostate ; Prostatectomy ; Prostatic Neoplasms ; Quality of Life ; Reproducibility of Results

BACKGROUND AND OBJECTIVES: The structural significance of the inappropriateness of left ventricular mass (iLVM) is known to be an important prognostic factor for cardiovascular events; however, the functional changes associated with iLVM have not been established. This study was performed to determine if diastolic dysfunction is associated with iLVM using a tissue Doppler technique. SUBJECTS AND METHODS: Three hundred sixty consecutive subjects, including 221 hypertension patients from the echocardiography database, were analyzed. Regarding the appropriateness of left ventricular (LV) mass, an observed/predicted ratio of LV mass (OPR) >130% was defined as inappropriate. Echocardiographic parameters, including early diastolic peak velocity (E)/late diastolic peak velocity (A), deceleration time (DT), isovolumetric relaxation time (IVRT), and E/early mitral annulus velocity (E'), were compared between the appropriate LV mass (aLVM) group and the iLVM group. RESULTS: Among transmitral flow parameters, only the E velocity was negatively correlated with the OPR when adjusted for age (adjusted r=-0.107, p=0.04). Based on multiple regression analysis, the OPR (beta=0.163, p=0.003), as well as age (beta=0.286, p=0.0001), systolic blood pressure (beta=0.120, p=0.019), fasting blood glucose (beta=0.098, p=0.042), and male gender (beta=0.157, p=0.002) were independent factors determining E/E'. The cholesterol level was not an independent factor (beta=-0.059, p=0.355). In the iLVM group (n=105), the adjusted E/E' was higher than in the aLVM group (n=255; 11.7+/-3.4 vs. 10.8+/-3.1, p=0.02), while the peak E flow velocity was significantly lower than in the aLVM group (70.9+/-15.1 vs. 75.5+/-17.6, p=0.03). CONCLUSION: Inappropriateness of LV mass is independently associated with increased E/E'. Thus, E/E' may be a useful parameter for the evaluation of diastolic dysfunction.
Blood Glucose ; Blood Pressure ; Cholesterol ; Deceleration ; Echocardiography ; Fasting ; Heart Ventricles ; Humans ; Hypertension ; Hypertrophy ; Male ; Relaxation

BACKGROUND AND OBJECTIVES: Inappropriately high left ventricular mass (iLVM) is known to be related to cardiovascular prognosis. A non-dipper pattern has a greater mean left ventricular (LV) mass than the dipper pattern in hypertensive patients. However, the appropriateness of LV mass in dipper or non-dipper patterns has not been adequately investigated. The aim of this study was to define the relationship between nocturnal dipping and the appropriateness of LV mass. SUBJECTS AND METHODS: Using the ambulatory blood pressure monitoring (ABPM) database, the data of 361 patients who underwent ABPM and echocardiography was analyzed retrospectively. Appropriateness of LV mass was calculated as observed/predicted ratio of LV mass (OPR) using a Korean-specified equation. Nocturnal dipping was expressed as percent fall in systolic blood pressure (BP) during the night compared to the day. RESULTS: Daytime, nighttime and 24 hours BP in hypertensive patients was 140.4+/-14.8 mmHg, 143.7+/-15.2 mmHg and 129.4+/-20.0 mmHg, respectively. OPR was 106.3+/-19.9% and nocturnal dipping was 10.2+/-10.9 mmHg. In a multiple linear regression model, 24 hours systolic BP (beta=0.097, p=0.043) and nocturnal dipping (beta=-0.098, p=0.046) were independent determinants of OPR as well as age (beta=0.130, p=0.025) and body mass index (BMI) (beta=0.363, p<0.001). Odds ratio of the non-dipper pattern was 2.134 for iLVM (p=0.021) and 3.694 for obesity (p<0.001; BMI >25 kg/m2). CONCLUSION: The non-dipper pattern is independently associated with iLVM in hypertensive patients as well as obesity.
Blood Pressure ; Blood Pressure Monitoring, Ambulatory ; Body Mass Index ; Echocardiography ; Humans ; Hypertension ; Hypertrophy, Left Ventricular ; Linear Models ; Obesity ; Odds Ratio ; Prognosis ; Retrospective Studies

BACKGROUND AND OBJECTIVES: The aim of the study was to evaluate the difference of temporal lability in myocardial repolarization between acute non-Q (NQMI) and Q-wave myocardial infarction (QMI), and to discern whether the locations of myocardial infarction influence such temporal lability. SUBJECTS AND METHODS: Twelve patients with NQMI and 28 with QMI, including 16 anterior (AMI) and 12 inferior MI (IMI) patients were enrolled. Twenty four-hour ambulatory ECG recordings of each patient were analyzed, and the digitized data was partitioned into 30-min sections. The QT intervals were measured using a template matching strategy. We then calculated the low (LF:0.03 - 0.15 Hz) and high frequency (HF:0.15 - 0.4 Hz) power of the QT interval variability using an algorithm capable of removing the influence of the RR-interval on QT interval variability (Normalized Idioventricular QT variability Index:IV-QT). RESULTS: For patients with QMI, the low frequency IV QT (LF IV-QT) was higher than that of NQMI (1.941+/-0.101 and 1.556+/-0.114 respectively, p<0.05). No difference was seen in the high frequency IV QT (HF IV-QT) of the two groups. For QMI patients, both the LF IV-QT and HF IV-QT were higher in day time (6AM-6PM) than in night time (6PM-6AM). Comparing the differences of these indices by the location of QMI, both the LF IV-QT and HF IV-QT of AMI were higher than those of IMI patients (2.231+/-0.135 vs 1.355+/-0.131 and 2.341+/-0.161 vs 1.346+/-0.145 respectively, p<0.0005). Both indices of each group also demonstrated a circadian change. CONCLUSION: In cases of QMI, the temporal lability in myocardial repolarization is larger than that seen in NQMI. Moreover, it was worse in AMI than IMI. Finally, such temporal repolarization lability tends to have a circadian pattern in QMI.
Electrocardiography ; Electrocardiography, Ambulatory ; Humans ; Myocardial Infarction*

BACKGROUND AND OBJECTIVES: The left ventricular mass is known to be influenced by both hemodynamic and non-hemodynamic factors. Body size and gender are the most representative non-hemodynamic factors. This study was performed to establish the influences of these variables on the variation of the left ventricular mass in healthy Korean adults. SUBJECTS AND METHODS: 368 subjects (male=184, female=184), with a normal body mass index and blood pressure, were included in the echocardiographic analysis from the echocardiography database of the Hanyang University Hospital and of the Yangpyung Epidemiologic Survey 2004. The left ventricular mass was calculated using the equation: 1.04x(IVSd+LVDd+PWTd)3-LDVs3)x0.8+0.6. The stroke volume was calculated (mL/beat) using Teichholz's formula. The stroke work (SW in gram-meters/beat [g-m/beat]) was computed as the cuff systolic BPxstroke volumex0.0144. RESULTS: The stroke work (SW) was the most important factor associated with the LV mass (adjusted R2=0.501, p<0.001), and body weight, age and gender were independent factors (adjusted R2=0.642). In a regression model, including stroke work, gender and height2.7, the LV mass was predicted by the equation: 54.9+7.62xheight (m2.7)+0.67xSW (g-m/beat)-13.2xgender (male=1, female=2)(constant=54.9+/-14.7 g, adjusted R2=0.576, SEE=21.67, p=0.001). CONCLUSION: As with the studies in the western countries, the stroke work, gender and height2.7 were important determinants of the left ventricular mass in Korean adults with a normal weight and normal blood pressure.
Adult* ; Blood Pressure* ; Body Mass Index ; Body Size* ; Body Weight ; Echocardiography ; Hemodynamics ; Humans ; Hypertrophy, Left Ventricular ; Ideal Body Weight* ; Stroke ; Stroke Volume

BACKGROUND: To prevent unsolved problems of medical devices, we hypothesized that combinatorial effects of zwitterionic functional group and anti-bacterial metal ions can reduce effectively the thrombosis and bacterial infection of polymeric biomaterials. In this research, we designed a novel series of zwitterionic polyurethane (zPU) additives to impart anti-thrombotic properties to a polyvinyl chloride (PVC) matrix. METHODS: We have synthesized zPUs by combination of various components and zPUs complexed with metal ions. Zwitterion group was prepared by reaction with 1,3-propane sultone and Nmethyldiethanolamine and metal ions were incorporated into sulfobetaine chains via molecular complexation. These zPU additives were characterized using FT-IR, 1H-NMR, elemental analysis, and thermal analysis. The PVC film blended with zPU additives were prepared by utilizing a solvent casting and hot melting process. RESULTS: Water contact angle demonstrated that the introduction of zwitterion group has improved hydrophilicity of polyurethanes dramatically. Protein adsorption test resulted in improved anti-fouling effects dependent on additive concentration and decreases in their effects by metal complexation. Platelet adhesion test revealed anti-fouling effects by additive blending but not significant as compared to protein resistance results. CONCLUSION With further studies, the synthesized zPUs and zPUs complexed with metal ions are expected to be used as good biomaterials in biomedical fields. Based on our results, we can carefully estimate that the enhanced anti-fouling effect contributed to reduced platelet adhesion.

BACKGROUND AND OBJECTIVES: Ambulatory arterial stiffness index (AASI) is well known as a predictor of cardiovascular mortality in hypertensive patients. Mathematically, AASI reflect the standard deviation (SD) of blood pressure (BP) variation. AASI is measured higher levels in non-dipper than dipper. Thus, AASI has a possibility of not only reflecting arterial stiffness but also BP variability and/or autonomic nervous dysfunction. SUBJECTS AND METHODS: Consecutive data from 418 untreated hypertensive patients were analyzed retrospectively. We examined the association between the 24-hour ambulatory BP monitoring (ABPM) parameters and AASI. RESULTS: AASI had a simple correlation with age (R=0.189, p<0.001), relative wall thickness (RWT) (R=0.115, p=0.019), left ventricular mass index (LVMI) (R=0.192, p<0.001), average systolic BP (SBP) (R=0.232, p<0.001), average pulse pressure (PP) (R=0.363, p<0.001), SD of diastolic BP (DBP) (R=-0.352, p<0.001), SD of PP (R=0.330, p<0.001), SD of heart rate (HR) (R=-0.268, p<0.001), and nocturnal dipping (R=-0.137, p=0.005). In multiple linear regression analysis model including clinical parameters and 24 hour-ABPM parameters, independent predictors of AASI were SD of PP (beta=1.246, p<0.001), SD of DBP (beta=-1.067, p<0.001), SD of SBP (beta=-0.197, p<0.001), and non-dipper (beta=0.054, p=0.033). CONCLUSION: AASI is closely correlated with BP variability. The result of this study shows that AASI is not only a parameter for arterial stiffness, but also a parameter for BP variability.
Autonomic Nervous System Diseases ; Blood Pressure ; Blood Pressure Monitoring, Ambulatory ; Heart Rate ; Humans ; Linear Models ; Retrospective Studies ; Vascular Stiffness