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Dive into the research topics where Kyoko Otani is active.

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Featured researches published by Kyoko Otani.


Journal of The American Society of Echocardiography | 2011

Age- and Gender-Dependency of Left Ventricular Geometry Assessed with Real-Time Three-Dimensional Transthoracic Echocardiography

Kyoko Kaku; Masaaki Takeuchi; Kyoko Otani; Lissa Sugeng; Hiromi Nakai; Nobuhiko Haruki; Hidetoshi Yoshitani; Nozomi Watanabe; Kiyoshi Yoshida; Yutaka Otsuji; Victor Mor-Avi; Roberto M. Lang

BACKGROUND Aging and gender may affect left ventricular (LV) mechanics. The aim of this study was to determine the age and gender dependency of LV mechanical indices obtained from real-time three-dimensional echocardiography (RT3DE). METHODS RT3DE was performed in 280 healthy subjects (age range, 1-88 years; 137 men). From full-volume data sets, LV endocardial and epicardial borders were semiautomatically traced using quantitative software. LV volumes and corresponding long-axis diameter were measured throughout the cardiac cycle. Sphericity index was defined as the ratio of LV volume and spherical volume, calculated as 4/3 × π × (long-axis diameter/2)(3). LV mass was calculated as (LV epicardial volume - LV endocardial volume) × 1.05. The ratio of LV mass to LV volume was also calculated. RESULTS The mean value of LV ejection fraction did not change with age. However, LV volumes, mass, sphericity index, and LV mass/volume ratio were altered by age: (1) sphericity index was highest in the first decade of age and then declined until the fifth decade, (2) LV mass/volume ratio significantly increased in older age, and (3) LV mass/volume ratio was significantly higher in aged women compared with age-matched men. CONCLUSIONS Age has heterogeneous effects on LV shape and LV mass/volume ratio, potentially due to the growing process of myocardial fibers and the surrounding architecture in the younger population, as well as the aging process, with an increase in vascular stiffness and a loss of myocytes in older populations. Higher LV mass/volume ratios in older women might be a contributor to the preferential development of diastolic heart failure in this population.


European Journal of Echocardiography | 2015

Normal values and clinical relevance of left atrial myocardial function analysed by speckle-tracking echocardiography: multicentre study

Daniel A. Morris; Masaaki Takeuchi; Maximilian Krisper; Clemens Köhncke; Tarek Bekfani; Tim Carstensen; Sabine Hassfeld; Marc Dorenkamp; Kyoko Otani; Kiyohiro Takigiku; Chisato Izumi; Satoshi Yuda; Konomi Sakata; Nobuyuki Ohte; Kazuaki Tanabe; Engin Osmanoglou; York Kühnle; Hans-Dirk Düngen; Satoshi Nakatani; Yutaka Otsuji; Wilhelm Haverkamp; Leif-Hendrik Boldt

AIMS The aim of this multicentre study was to determine the normal range and the clinical relevance of the myocardial function of the left atrium (LA) analysed by 2D speckle-tracking echocardiography (2DSTE). METHODS AND RESULTS We analysed 329 healthy adult subjects prospectively included in 10 centres and a validation group of 377 patients with left ventricular diastolic dysfunction (LVDD). LA myocardial function was analysed by LA strain rate peak during LA contraction (LA-SRa) and LA strain peak during LA relaxation (LA-Strain). The range of values of LA myocardial function in healthy subjects was LA-SRa -2.11 ± 0.61 s(-1) and LA-Strain 45.5 ± 11.4%, and the lowest expected values of these LA analyses (calculated as -1.96 SD from the mean of healthy subjects) were LA-SRa -0.91 s(-1) and LA-Strain 23.1%. Concerning the clinical relevance of these LA myocardial analyses, LA-SRa and LA-Strain detected subtle LA dysfunction in patients with LVDD, even though LA volumetric measurements were normal. In addition, in these patients we found that the functional class (dyspnoea-NYHA classification) was inversely related to both LA-Strain and LA-SRa. CONCLUSION In the present multicentre study analysing a large cohort of healthy subjects and patients with LVDD, the normal range and the clinical relevance of the myocardial function of the LA using 2DSTE have been determined.


Jacc-cardiovascular Imaging | 2013

Prognostic value of LA volumes assessed by transthoracic 3D echocardiography: comparison with 2D echocardiography.

Victor Chien-Chia Wu; Masaaki Takeuchi; Hiroshi Kuwaki; Mai Iwataki; Yasufumi Nagata; Kyoko Otani; Nobuhiko Haruki; Hidetoshi Yoshitani; Masahito Tamura; Haruhiko Abe; Kazuaki Negishi; Fen-Chiung Lin; Yutaka Otsuji

OBJECTIVES The hypothesis of this study was that minimal left atrial volume index (LAVImin) by 3-dimensional echocardiography (3DE) is the best predictor of future cardiovascular events. BACKGROUND Although maximal left atrial volume index (LAVImax) by 2-dimensional echocardiography (2DE) is a robust index for predicting prognosis, the prognostic value of LAVImin and the superiority of measurements by 3DE over 2DE have not been determined in a large group of patients. METHODS In protocol 1, we assessed age and sex dependency of LAVIs using 2DE and 3DE in 124 normal subjects and determined their cutoff values (mean + 2 SD). In protocol 2, 2-dimensional (2D) and 3-dimensional (3D) LAVImax/LAVImin were measured in 556 patients with high prevalence of cardiovascular disease. After excluding patients with atrial fibrillation, mitral valve disease, and age <18 years, 439 subjects were followed to record major adverse cardiovascular events (MACE). Patients were divided into 2 groups by the cutoff criteria of LAVI in each method. RESULTS In protocol 1, there was no significant age and sex dependency for each 2D and 3D LAVI. In protocol 2, during a mean of 2.5 years of follow-up, MACE developed in 88 patients, including 32 cardiac deaths. Kaplan-Meier survival analyses showed that all 4 LAVI cutoff criteria had significant predictive power of MACE. After variables were adjusted for clinical variables and left ventricular ejection fraction, all 4 methods were still independently and significantly associated with MACE, but 3D-derived LAVImin had the highest risk ratio. 3D LAVImin also had an incremental prognostic value over 3D LAVImax. CONCLUSIONS LAVIs by both 2DE and 3DE are powerful predictors of future cardiac events. 3D LAVImin tended to have a stronger and additive prognostic value than 3D LAVImax.


Journal of The American Society of Echocardiography | 2013

Effect of Through-Plane and Twisting Motion on Left Ventricular Strain Calculation: Direct Comparison between Two-Dimensional and Three-Dimensional Speckle-Tracking Echocardiography

Victor Chien-Chia Wu; Masaaki Takeuchi; Kyoko Otani; Nobuhiko Haruki; Hidetoshi Yoshitani; Masahito Tamura; Haruhiko Abe; Fen-Chiung Lin; Yutaka Otsuji

BACKGROUND The aim of this study was to investigate the effect of out-of-plane motion on discrepancies in strain measurements between two-dimensional (2D) and three-dimensional (3D) echocardiography. METHODS Two-dimensional and 3D data sets were acquired in 54 patients. Using 2D and 3D speckle-tracking software, global circumferential strain (CS) and longitudinal strain (LS) as well as CS and LS at three left ventricular (LV) levels was measured. The effect of through-plane motion was assessed by mitral annular displacement. RESULTS Although a good correlation of global CS was noted between the two methods (r = 0.80, P < .01), mean values of global CS were significantly higher on 3D compared with 2D echocardiography. Correlations of CS and their mean differences were 0.65 and -4.61 at the basal level, 0.76 and -4.17 at the midventricular level, and 0.60 and -2.23 at the apical level, respectively. Correlation of global CS between the two methods was higher in patients who showed mitral annular displacement < 9.4 mm (r = 0.81) compared with those with mitral annular displacement ≥ 9.4 mm (r = 0.61). A good correlation of global LS (r = 0.89, P < .01) was noted, with no significant bias. Correlations of LS and their mean differences were 0.52 and 1.59 at the basal level, 0.89 and -1.17 at the midventricular level, and 0.73 and 1.46 at the apical level, respectively. Correlation of LS between the two methods was higher in patients who showed LV twist < 12.2° (r = 0.94) compared with patients with LV twist ≥ 12.2° (r = 0.68). CONCLUSIONS Through-plane motion produced discrepancies in CS measurements, especially at the LV basal level. Larger bias of LS at the basal and apical LV levels compared with the midventricular level between the two methods suggests that LV twisting also affects the calculation of 2D LS.


Journal of The American Society of Echocardiography | 2014

Multidirectional Global Left Ventricular Systolic Function in Normal Subjects and Patients with Hypertension: Multicenter Evaluation

Daniel A. Morris; Kyoko Otani; Tarek Bekfani; Kiyohiro Takigiku; Chisato Izumi; Satoshi Yuda; Konomi Sakata; Nobuyuki Ohte; Kazuaki Tanabe; Katharina Friedrich; York Kühnle; Satoshi Nakatani; Yutaka Otsuji; Wilhelm Haverkamp; Leif-Hendrik Boldt; Masaaki Takeuchi

BACKGROUND The aim of this multicenter study was to determine the normal ranges and the clinical relevance of multidirectional systolic parameters to evaluate global left ventricular (LV) systolic function. METHODS Three hundred twenty-three healthy adult subjects prospectively included at 10 centers and a cohort of 310 patients with hypertension were analyzed. Multidirectional global LV systolic function was analyzed using two-dimensional speckle-tracking echocardiography by means of two indices: longitudinal-circumferential systolic index (the average of longitudinal and circumferential global systolic strain) and global systolic index (the average of longitudinal, circumferential, and radial global systolic strain). RESULTS The ranges of values of the multidirectional systolic parameters in healthy subjects were -21.22 ± 2.22% for longitudinal-circumferential systolic index and 29.71 ± 5.28% for global systolic index. In addition, the lowest expected values of these multidirectional indices were determined in this population (calculated as -1.96 SDs from the mean): -16.86% for longitudinal-circumferential systolic index and 19.36% for global systolic index. Concerning the clinical relevance of these measurements, these indices indicated the presence of subtle LV global systolic dysfunction in patients with hypertension, even though LV global longitudinal systolic strain and LV ejection fraction were normal. Moreover, in these patients, functional class (dyspnea [New York Heart Association classification]) was inversely related to both the longitudinal-circumferential index and the global systolic index. CONCLUSIONS In the present multicenter study analyzing a large cohort of healthy subjects and patients with hypertension, the normal range and the clinical relevance of multidirectional systolic parameters to evaluate global LV systolic function have been determined.


Circulation | 2012

Evidence of a Vicious Cycle in Mitral Regurgitation With Prolapse Secondary Tethering Attributed to Primary Prolapse Demonstrated by Three-Dimensional Echocardiography Exacerbates Regurgitation

Kyoko Otani; Masaaki Takeuchi; Kyoko Kaku; Nobuhiko Haruki; Hidetoshi Yoshitani; Masataka Eto; Masahito Tamura; Masahiro Okazaki; Haruhiko Abe; Yoshihisa Fujino; Yousuke Nishimura; Robert A. Levine; Yutaka Otsuji

Background— In patients with mitral valve prolapse, nonprolapsed leaflets are often apically tented. We hypothesized that secondary left ventricular dilatation attributed to primary mitral regurgitation (MR) causes papillary muscle (PM) displacement, resulting in this leaflet tenting/tethering, and that secondary tethering further exacerbates malcoaptation and contributes to MR severity. Methods and Results— Three-dimensional transesophageal echocardiography was performed in 25 patients with posterior mitral leaflet prolapse with an intact anterior mitral leaflet (AML) and 20 controls. From 3D zoom data sets, 11 equidistant antero-posterior cut planes of the mitral valve at midsystole were obtained. In each plane, tenting area of nonprolapsed leaflet and prolapse area of prolapsed leaflet were measured. Prolapse/tenting volume of each region was obtained as the product of interslice distance and the prolapse/tenting area. AML tenting volume and whole leaflet prolapse/tenting volume were then obtained. The PM tethering distance between PM tips and anterior mitral annulus was measured from 3D full-volume data sets. The severity of MR was quantified by vena contracta area extracted from color 3D transesophageal echocardiography data sets. AML tenting volume was significantly larger in patients with posterior mitral leaflet prolapse compared with that in controls (1.2±0.5 versus 0.6±0.2 mL/m2; P<0.001). Multivariate regression analysis identified independent contribution to AML tenting volume from an increase in PM tethering distance. Multivariate regression analysis identified independent contributions to MR severity (vena contracta area) from both whole leaflet tenting volume (r=0.44; P<0.05) and prolapse volume (r=0.44; P<0.05). AML tenting volume decreased along with left ventricular volume and PM tethering distance postrepair (n=8; P<0.01). Conclusions— These results suggest that primary mitral valve prolapse with MR causes secondary mitral leaflet tethering with PM displacement by left ventricular dilatation, which further exacerbates valve leakage, constituting a vicious cycle that would suggest a pathophysiologic rationale for early surgical repair.


Circulation-cardiovascular Imaging | 2017

Prognostic value of right ventricular ejection fraction assessed by transthoracic 3D echocardiography

Yasufumi Nagata; Victor Chien-Chia Wu; Yuichiro Kado; Kyoko Otani; Fen-Chiung Lin; Yutaka Otsuji; Kazuaki Negishi; Masaaki Takeuchi

Background— Cardiac magnetic resonance is the gold standard for the evaluation of right ventricular (RV) volumes, but it is impractical to perform in every patient. Although reference values of RV volumes and RV ejection fraction by 3D transthoracic echocardiography (3DTTE) have been established, their prognostic values have not been elucidated yet. We hypothesized that RV ejection fraction measured by 3DTTE (3DRVEF) predicts future cardiovascular events. Methods and Results— In protocol 1, we determined the accuracy of RV volumes and RV ejection fraction measurements by 3DTTE against cardiac magnetic resonance in 60 subjects. In protocol 2, 3DRVEF was measured in 446 patients with various cardiovascular diseases. Study subjects were followed up to record cardiac death and major adverse cardiovascular events. In protocol 1, 3DTTE-determined RV end-diastolic volume, end-systolic volume, and RV ejection fraction had good correlations to those by cardiac magnetic resonance (r=0.74–0.90). In protocol 2, 38 cardiac deaths and 88 major adverse cardiovascular events occurred during a median follow-up of 4.1 years. Univariable Cox proportional analysis revealed that 3DRVEF was associated with both cardiac death (P<0.0001) and major adverse cardiovascular event (P<0.0001). 3DRVEF remained as an independent predictor for cardiac death (P<0.0001) and major adverse cardiovascular event (P<0.0001) even in a stepwise multivariable Cox proportional hazard analysis. Classification and regression-tree analysis demonstrated that 3DRVEF played an important role for risk stratification. Conclusions— 3DTTE-determined RV ejection fraction was independently associated with cardiac outcomes in patients with diverse backgrounds. 3DRVEF offered incremental value over clinical risk factors and the other echocardiographic parameters including left ventricular systolic and diastolic function for predicting future adverse outcome.


European Journal of Echocardiography | 2018

Three-dimensional echocardiographic quantification of the left-heart chambers using an automated adaptive analytics algorithm: multicentre validation study.

Diego Medvedofsky; Victor Mor-Avi; Mihaela Silvia Amzulescu; Covadonga Fernández-Golfín; Rocio Hinojar; Mark Monaghan; Kyoko Otani; Joseph Reiken; Masaaki Takeuchi; Wendy Tsang; Jean-Louis Vanoverschelde; Mathivathana Indrajith; Lynn Weinert; Jose Luis Zamorano; Roberto M. Lang

Aims Although recommended by current guidelines, adoption of three-dimensional echocardiographic (3DE) chamber quantification in clinical practice has lagged because of time-consuming analysis. We recently validated an automated algorithm that measures left atrial (LA) and left ventricular (LV) volumes and ejection fraction (EF). This study aimed to determine the accuracy and reproducibility of these measurements in a multicentre setting. Methods and results 180 patients underwent 3DE imaging (Philips) at six sites. Images were analysed using automated HeartModel (HM) software with endocardial border correction when necessary and by manual tracing. Measurements were performed by each site and by the Core Laboratory (CL) as the reference. Inter-technique comparisons included HM measurements by the sites against manual tracing by CL, and showed strong correlations (r-values: LVEDV: 0.97, LVESV: 0.97, LVEF: 0.88, LAV: 0.96), with the automated technique slightly underestimating LV volumes (biases: LVEDV: -14 ± 20 ml, LVESV: -6 ± 20 ml), LVEF (-2 ± 7%) and LAV (-9 ± 10 ml). Intra-technique comparisons included HM measurements by the sites against CL, with and without corrections. Corrections were unnecessary or minimal in most patients, and improved the measurements only modestly. Comparisons without corrections showed perfect agreement for all parameters. With corrections, correlations were better (r-values: LVEDV: 0.99, LVESV: 0.99, LVEF: 0.94, LAV: 0.99) and biases (LVEDV: -8 ± 12 ml, LVESV: -6 ± 12 ml, LVEF: 1 ± 5%, LAV: -10 ± 6 ml) smaller than in inter-technique comparison. All automated measurements with corrections were more reproducible than manual measurements. Conclusion Automated 3DE analysis of left-heart chambers is an accurate alternative to conventional manual methodology, which yields almost the same values across laboratories and is more reproducible. This technique may contribute towards full integration of 3DE quantification into clinical routine.


Open Heart | 2014

Calcific extension towards the mitral valve causes non-rheumatic mitral stenosis in degenerative aortic stenosis: real-time 3D transoesophageal echocardiography study

Mai Iwataki; Masaaki Takeuchi; Kyoko Otani; Hiroshi Kuwaki; Hidetoshi Yoshitani; Haruhiko Abe; Roberto M. Lang; Robert A. Levine; Yutaka Otsuji

Objective Mitral annular/leaflet calcification (MALC) is frequently observed in patients with degenerative aortic stenosis (AS). However, the impact of MALC on mitral valve function has not been established. We aimed to investigate whether MALC reduces mitral annular area and restricts leaflet opening, resulting in non-rheumatic mitral stenosis. Methods Real-time three-dimensional transoesophageal images of the mitral valve were acquired in 101 patients with degenerative AS and 26 control participants. The outer and inner borders of the mitral annular area (MAA) and the maximal leaflet opening angle were measured at early diastole. The mitral valve area (MVA) was calculated as the left ventricular stroke volume divided by the velocity time integral of the transmitral flow velocity. Results Although the outer MAA was significantly larger in patients with AS compared to control participants (8.2±1.3 vs 7.3±0.9 cm2, p<0.001), the inner MAA was significantly smaller (4.5±1.1 vs 5.9±0.9 cm2, p<0.001), resulting in an average decrease of 45% in the effective MAA. The maximal anterior and posterior leaflet opening angle was also significantly smaller in patients with AS (64±10 vs 72±8°, p<0.001, 71±12 vs 87±7°, p<0.001). Thus, MVA was significantly smaller in patients with AS (2.5±1.0 vs 3.8±0.8 cm2, p<0.001). Twenty-four (24%) patients with AS showed MVA <1.5 cm2. Multivariate regression analysis including parameters for mitral valve geometry revealed that a decrease in effective MAA and a reduced posterior leaflet opening angle were independent predictors for MVA. Conclusions Calcific extension to the mitral valve in patients with AS reduced effective MAA and the leaflet opening, resulting in a significant non-rheumatic mitral stenosis in one-fourth of the patients.


Heart Lung and Circulation | 2013

Immediate Amelioration of Mechanical Pulsus Alternans by Adaptive Servo-ventilation Therapy

Nobuhiko Haruki; Masaaki Takeuchi; Hidetoshi Yoshitani; Kyoko Otani; Hiroshi Kuwaki; Mai Iwataki; Haruhiko Abe; Masahito Tamura; Masahiro Okazaki; Yutaka Otsuji

echanical pulsus alternans is sometimes seen inpatients with severe heart failure. This case reportdescribes a patient with medically refractory acute heartfailure due to severe left ventricular (LV) systolic dys-function withpulsusalternans,whereshort-termadaptiveservo-ventilation (ASV)therapyimmediatelyamelioratedthe mechanical pulsus alternans.A 52 year-old male was admitted to the hospitaldue to progressive exertional dyspnoea. Auscultationof the chest revealed fine crackles over both lungs.An S3 gallop rhythm and a grade 2/6 of pansystolicmurmur were audible at the apex. His blood pres-sure was 110/70mmHg and heart rate was 120bpm.Chest X ray showed cardiomegaly with bilateral pul-monary congestion. The electrocardiogram showed sinustachycardia with normal QRS duration. Blood exami-nation on admission revealed remarkable elevation inthe serum level of brain natriuretic peptide (BNP) of1740 pg/dl (<18.4pg/ml). Echocardiography showed aseverely dilated left ventricle (LV) with an ejection frac-tion of 15% (Movie 1). Estimated systolic pulmonaryartery pressure from tricuspid regurgitation velocity was64 mmHg. Initial treatment with angiotensin II recep-tor blockers, intravenous diuretics, and carperitide failedto provide a favourable response. Subsequently, intra-venous phosphodiesterase III inhibitor for three daysdid not improve his condition. Radial pulse revealedalternating strong and weak beats, indicating mechanicalpulsus alternans. Repeated echocardiography demon-strated alternating pulsed Doppler flow velocities acrossthe LV outflow tract (LVOT) with no significant change ofLV size and systolic function compared to the previousstudy (Fig. 1). Although oxygen saturation was preservedby

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Yutaka Otsuji

University of Occupational and Environmental Health Japan

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Nobuhiko Haruki

University Health Network

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Haruhiko Abe

University of Occupational and Environmental Health Japan

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Masahito Tamura

University of Occupational and Environmental Health Japan

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