The Experts below are selected from a list of 219 Experts worldwide ranked by ideXlab platform
Kazuaki Wakami - One of the best experts on this subject based on the ideXlab platform.
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abstract 15137 vector flow mapping is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2014Co-Authors: Kazuaki Wakami, Tomomitsu Tani, Kenta Hachiya, Syunsuke Murai, Hidekatsu Fukuta, Toshihiko Goto, Hiroshi Fujita, Nobuyuki OhteAbstract:Background: We previously reported that the inertia force (IF) of blood flowing out of left ventricle (LV) during late-Systole produces greater LV elastic recoil force and brings faster LV relaxation. Vector flow mapping (VFMTM, Hitachi-Aloka) enables us to see blood flow velocity vectors that are generated from conventional color Doppler imaging data at any phase of cardiac cycle without angle dependency. Using VFM, kinetic energy (KE) of ejecting blood flow during Systole at the LV outflow tract (LVOT) can be obtained. Thus, we investigated whether the KE obtained at the LVOT during late Systole (KE-ls) had any relations with the IF and invasively obtained LV function parameters. Method: Study subjects were 33 patients who underwent diagnostic cardiac catheterization and echocardiographic examination on the same day. Color Doppler images were acquired in the apical 3-chamber view. The frame rate ranged was from 40 to 51 frames per minute. Data analyses were performed offline using the commercially avail...
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correlation between left ventricular end diastolic pressure and peak left atrial wall strain during left ventricular Systole
Journal of The American Society of Echocardiography, 2009Co-Authors: Kazuaki Wakami, Kaoru Asada, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Hitomi Narita, Genjiro KimuraAbstract:Objective Left atrial (LA) reservoir function is determined by integration of LA relaxation and left ventricular (LV) systolic function, and LV diastolic dysfunction increases LA volume at end Systole. This study investigates the effect of LV end-diastolic pressure on LA wall tension during LV Systole. Methods A total of 101 stable patients with sinus rhythm undergoing cardiac catheterization were studied. LA wall extension during LV Systole was evaluated as LA wall strain in the longitudinal direction obtained using two-dimensional ultrasound speckle tracking imaging. LV end-diastolic pressure and LV end-systolic and end-diastolic volumes were obtained in cardiac catheterization, and LV ejection fraction was determined. Results Peak LA wall strain during LV Systole had a significant inverse correlation with LV end-diastolic pressure ( r = − 0.76, P r = − 0.64, P Conclusion Elevated LV end-diastolic pressure is associated with a decrease of peak LA wall strain in the longitudinal direction during LV Systole. In patients with peak LA wall strain during LV Systole of less than 30%, the majority had elevated LV end-diastolic pressure, while most patients with peak LA wall strain during LV Systole 45% or higher had normal LV end-diastolic pressures. In patients whose LV ejection fraction is 50% or more, when peak LA wall strain during LV Systole is between 30% and 44%, it is not possible to predict LV end-diastolic pressure from peak LA wall strain measures.
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abstract 4734 echodynamography is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2008Co-Authors: Kazuaki Wakami, Kaoru Asada, Chika Kato, Syogo Suzuki, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Genjiro KimuraAbstract:We previously reported that the inertia force (IF) of the blood flowing out of left ventricle (LV) during late systolic phase produces greater LV elastic recoil force and brings faster LV relaxation. Echodynamography (ALOKA) is a novel technique that enables us to obtain the flow velocity vector from conventional color Doppler velocity data on the range of interest at any phase of cardiac cycle without angle dependency. We investigated whether the flow velocity vector obtained at LV outflow tract (LVOT) in late Systole had a relation with IF and invasively obtained LV relaxation parameters. Method: Study subjects were consecutive 26 patients who underwent diagnostic cardiac catheterization and conventional color Doppler imaging on the same day. Color Doppler image was acquired in the apical 3-chamber view. The analyses for flow velocity vector were performed offline using an echo image analyzer. The late systolic velocity of the blood flowing was obtained as an average value of the L VOT (V LVOT −late Systole). LV pressure was obtained using a catheter-tipped micromanometer. From the recorded pressure waves, first derivative of LV pressure (dP/dt) and a time constant τ of LV pressure decay during isovolumic relaxation were calculated. From LV pressure-dP/dt relationships (phase loop), IF was determined. Results: A significant positive correlation was observed between the V LVOT -late Systole and IF (r=0.75, p LVOT -late Systole also had significant correlations both with peak negative dP/dt (r=0.49, p Conclusion: This study indicates that the V LVOT -late Systole, which may be a noninvasive substitute for IF, has significant correlations with the parameters of LV relaxation. Echodynamography is a new useful technique to estimate LV early diastolic function.
Nobuyuki Ohte - One of the best experts on this subject based on the ideXlab platform.
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abstract 15137 vector flow mapping is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2014Co-Authors: Kazuaki Wakami, Tomomitsu Tani, Kenta Hachiya, Syunsuke Murai, Hidekatsu Fukuta, Toshihiko Goto, Hiroshi Fujita, Nobuyuki OhteAbstract:Background: We previously reported that the inertia force (IF) of blood flowing out of left ventricle (LV) during late-Systole produces greater LV elastic recoil force and brings faster LV relaxation. Vector flow mapping (VFMTM, Hitachi-Aloka) enables us to see blood flow velocity vectors that are generated from conventional color Doppler imaging data at any phase of cardiac cycle without angle dependency. Using VFM, kinetic energy (KE) of ejecting blood flow during Systole at the LV outflow tract (LVOT) can be obtained. Thus, we investigated whether the KE obtained at the LVOT during late Systole (KE-ls) had any relations with the IF and invasively obtained LV function parameters. Method: Study subjects were 33 patients who underwent diagnostic cardiac catheterization and echocardiographic examination on the same day. Color Doppler images were acquired in the apical 3-chamber view. The frame rate ranged was from 40 to 51 frames per minute. Data analyses were performed offline using the commercially avail...
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correlation between left ventricular end diastolic pressure and peak left atrial wall strain during left ventricular Systole
Journal of The American Society of Echocardiography, 2009Co-Authors: Kazuaki Wakami, Kaoru Asada, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Hitomi Narita, Genjiro KimuraAbstract:Objective Left atrial (LA) reservoir function is determined by integration of LA relaxation and left ventricular (LV) systolic function, and LV diastolic dysfunction increases LA volume at end Systole. This study investigates the effect of LV end-diastolic pressure on LA wall tension during LV Systole. Methods A total of 101 stable patients with sinus rhythm undergoing cardiac catheterization were studied. LA wall extension during LV Systole was evaluated as LA wall strain in the longitudinal direction obtained using two-dimensional ultrasound speckle tracking imaging. LV end-diastolic pressure and LV end-systolic and end-diastolic volumes were obtained in cardiac catheterization, and LV ejection fraction was determined. Results Peak LA wall strain during LV Systole had a significant inverse correlation with LV end-diastolic pressure ( r = − 0.76, P r = − 0.64, P Conclusion Elevated LV end-diastolic pressure is associated with a decrease of peak LA wall strain in the longitudinal direction during LV Systole. In patients with peak LA wall strain during LV Systole of less than 30%, the majority had elevated LV end-diastolic pressure, while most patients with peak LA wall strain during LV Systole 45% or higher had normal LV end-diastolic pressures. In patients whose LV ejection fraction is 50% or more, when peak LA wall strain during LV Systole is between 30% and 44%, it is not possible to predict LV end-diastolic pressure from peak LA wall strain measures.
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abstract 4734 echodynamography is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2008Co-Authors: Kazuaki Wakami, Kaoru Asada, Chika Kato, Syogo Suzuki, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Genjiro KimuraAbstract:We previously reported that the inertia force (IF) of the blood flowing out of left ventricle (LV) during late systolic phase produces greater LV elastic recoil force and brings faster LV relaxation. Echodynamography (ALOKA) is a novel technique that enables us to obtain the flow velocity vector from conventional color Doppler velocity data on the range of interest at any phase of cardiac cycle without angle dependency. We investigated whether the flow velocity vector obtained at LV outflow tract (LVOT) in late Systole had a relation with IF and invasively obtained LV relaxation parameters. Method: Study subjects were consecutive 26 patients who underwent diagnostic cardiac catheterization and conventional color Doppler imaging on the same day. Color Doppler image was acquired in the apical 3-chamber view. The analyses for flow velocity vector were performed offline using an echo image analyzer. The late systolic velocity of the blood flowing was obtained as an average value of the L VOT (V LVOT −late Systole). LV pressure was obtained using a catheter-tipped micromanometer. From the recorded pressure waves, first derivative of LV pressure (dP/dt) and a time constant τ of LV pressure decay during isovolumic relaxation were calculated. From LV pressure-dP/dt relationships (phase loop), IF was determined. Results: A significant positive correlation was observed between the V LVOT -late Systole and IF (r=0.75, p LVOT -late Systole also had significant correlations both with peak negative dP/dt (r=0.49, p Conclusion: This study indicates that the V LVOT -late Systole, which may be a noninvasive substitute for IF, has significant correlations with the parameters of LV relaxation. Echodynamography is a new useful technique to estimate LV early diastolic function.
Genjiro Kimura - One of the best experts on this subject based on the ideXlab platform.
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correlation between left ventricular end diastolic pressure and peak left atrial wall strain during left ventricular Systole
Journal of The American Society of Echocardiography, 2009Co-Authors: Kazuaki Wakami, Kaoru Asada, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Hitomi Narita, Genjiro KimuraAbstract:Objective Left atrial (LA) reservoir function is determined by integration of LA relaxation and left ventricular (LV) systolic function, and LV diastolic dysfunction increases LA volume at end Systole. This study investigates the effect of LV end-diastolic pressure on LA wall tension during LV Systole. Methods A total of 101 stable patients with sinus rhythm undergoing cardiac catheterization were studied. LA wall extension during LV Systole was evaluated as LA wall strain in the longitudinal direction obtained using two-dimensional ultrasound speckle tracking imaging. LV end-diastolic pressure and LV end-systolic and end-diastolic volumes were obtained in cardiac catheterization, and LV ejection fraction was determined. Results Peak LA wall strain during LV Systole had a significant inverse correlation with LV end-diastolic pressure ( r = − 0.76, P r = − 0.64, P Conclusion Elevated LV end-diastolic pressure is associated with a decrease of peak LA wall strain in the longitudinal direction during LV Systole. In patients with peak LA wall strain during LV Systole of less than 30%, the majority had elevated LV end-diastolic pressure, while most patients with peak LA wall strain during LV Systole 45% or higher had normal LV end-diastolic pressures. In patients whose LV ejection fraction is 50% or more, when peak LA wall strain during LV Systole is between 30% and 44%, it is not possible to predict LV end-diastolic pressure from peak LA wall strain measures.
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abstract 4734 echodynamography is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2008Co-Authors: Kazuaki Wakami, Kaoru Asada, Chika Kato, Syogo Suzuki, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Genjiro KimuraAbstract:We previously reported that the inertia force (IF) of the blood flowing out of left ventricle (LV) during late systolic phase produces greater LV elastic recoil force and brings faster LV relaxation. Echodynamography (ALOKA) is a novel technique that enables us to obtain the flow velocity vector from conventional color Doppler velocity data on the range of interest at any phase of cardiac cycle without angle dependency. We investigated whether the flow velocity vector obtained at LV outflow tract (LVOT) in late Systole had a relation with IF and invasively obtained LV relaxation parameters. Method: Study subjects were consecutive 26 patients who underwent diagnostic cardiac catheterization and conventional color Doppler imaging on the same day. Color Doppler image was acquired in the apical 3-chamber view. The analyses for flow velocity vector were performed offline using an echo image analyzer. The late systolic velocity of the blood flowing was obtained as an average value of the L VOT (V LVOT −late Systole). LV pressure was obtained using a catheter-tipped micromanometer. From the recorded pressure waves, first derivative of LV pressure (dP/dt) and a time constant τ of LV pressure decay during isovolumic relaxation were calculated. From LV pressure-dP/dt relationships (phase loop), IF was determined. Results: A significant positive correlation was observed between the V LVOT -late Systole and IF (r=0.75, p LVOT -late Systole also had significant correlations both with peak negative dP/dt (r=0.49, p Conclusion: This study indicates that the V LVOT -late Systole, which may be a noninvasive substitute for IF, has significant correlations with the parameters of LV relaxation. Echodynamography is a new useful technique to estimate LV early diastolic function.
Jim M. Wild - One of the best experts on this subject based on the ideXlab platform.
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right ventricular mass has better reproducibility in Systole than diastole in patients with suspected pulmonary hypertension
Journal of Cardiovascular Magnetic Resonance, 2015Co-Authors: Andrew J Swift, Dave Capener, David G Kiely, Jim M. WildAbstract:Results 30 consecutive patients with suspected pulmonary hypertension were studied by both independent observers. RV mass measured in Systole had higher ICC agreement than diastole (0.983 verses 0.947) and showed less bias at Bland-Altman analysis, 1.9g compared to 8.7g, Figure 1. Of note, RV mass measurements were significantly higher when measured in Systole than diastole, with a mean difference of 10g (95% confidence interval of 6.6 to 13.2, p<0.0001). Bland Altman analysis shows RV mass measured in Systole to be systematically higher than in diastole with a bias of 9.9g, with limits of agreement ranging from -27.4g to 7.6g. Figure 2 illustrates that the RV endocardial border is more easily appreciated in Systole compared to diastole in patients with and without pulmonary hypertension. Conclusions RV mass possess a higher reproducibility profile at endSystole than end-diastole in patients with suspected pulmonary hypertension, this finding is of clinical relevance as mass measurements are typically measured in diastole.
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Right ventricular mass has better reproducibility in Systole than diastole in patients with suspected pulmonary hypertension
Journal of Cardiovascular Magnetic Resonance, 2015Co-Authors: Andrew J Swift, Dave Capener, David G Kiely, Jim M. WildAbstract:Results 30 consecutive patients with suspected pulmonary hypertension were studied by both independent observers. RV mass measured in Systole had higher ICC agreement than diastole (0.983 verses 0.947) and showed less bias at Bland-Altman analysis, 1.9g compared to 8.7g, Figure 1. Of note, RV mass measurements were significantly higher when measured in Systole than diastole, with a mean difference of 10g (95% confidence interval of 6.6 to 13.2, p
Hidekatsu Fukuta - One of the best experts on this subject based on the ideXlab platform.
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abstract 15137 vector flow mapping is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2014Co-Authors: Kazuaki Wakami, Tomomitsu Tani, Kenta Hachiya, Syunsuke Murai, Hidekatsu Fukuta, Toshihiko Goto, Hiroshi Fujita, Nobuyuki OhteAbstract:Background: We previously reported that the inertia force (IF) of blood flowing out of left ventricle (LV) during late-Systole produces greater LV elastic recoil force and brings faster LV relaxation. Vector flow mapping (VFMTM, Hitachi-Aloka) enables us to see blood flow velocity vectors that are generated from conventional color Doppler imaging data at any phase of cardiac cycle without angle dependency. Using VFM, kinetic energy (KE) of ejecting blood flow during Systole at the LV outflow tract (LVOT) can be obtained. Thus, we investigated whether the KE obtained at the LVOT during late Systole (KE-ls) had any relations with the IF and invasively obtained LV function parameters. Method: Study subjects were 33 patients who underwent diagnostic cardiac catheterization and echocardiographic examination on the same day. Color Doppler images were acquired in the apical 3-chamber view. The frame rate ranged was from 40 to 51 frames per minute. Data analyses were performed offline using the commercially avail...
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correlation between left ventricular end diastolic pressure and peak left atrial wall strain during left ventricular Systole
Journal of The American Society of Echocardiography, 2009Co-Authors: Kazuaki Wakami, Kaoru Asada, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Hitomi Narita, Genjiro KimuraAbstract:Objective Left atrial (LA) reservoir function is determined by integration of LA relaxation and left ventricular (LV) systolic function, and LV diastolic dysfunction increases LA volume at end Systole. This study investigates the effect of LV end-diastolic pressure on LA wall tension during LV Systole. Methods A total of 101 stable patients with sinus rhythm undergoing cardiac catheterization were studied. LA wall extension during LV Systole was evaluated as LA wall strain in the longitudinal direction obtained using two-dimensional ultrasound speckle tracking imaging. LV end-diastolic pressure and LV end-systolic and end-diastolic volumes were obtained in cardiac catheterization, and LV ejection fraction was determined. Results Peak LA wall strain during LV Systole had a significant inverse correlation with LV end-diastolic pressure ( r = − 0.76, P r = − 0.64, P Conclusion Elevated LV end-diastolic pressure is associated with a decrease of peak LA wall strain in the longitudinal direction during LV Systole. In patients with peak LA wall strain during LV Systole of less than 30%, the majority had elevated LV end-diastolic pressure, while most patients with peak LA wall strain during LV Systole 45% or higher had normal LV end-diastolic pressures. In patients whose LV ejection fraction is 50% or more, when peak LA wall strain during LV Systole is between 30% and 44%, it is not possible to predict LV end-diastolic pressure from peak LA wall strain measures.
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abstract 4734 echodynamography is a novel useful technique in assessing inertia force of late systolic aortic flow and left ventricular early diastolic function
Circulation, 2008Co-Authors: Kazuaki Wakami, Kaoru Asada, Chika Kato, Syogo Suzuki, Seiji Mukai, Nobuyuki Ohte, Hidekatsu Fukuta, Toshihiko Goto, Genjiro KimuraAbstract:We previously reported that the inertia force (IF) of the blood flowing out of left ventricle (LV) during late systolic phase produces greater LV elastic recoil force and brings faster LV relaxation. Echodynamography (ALOKA) is a novel technique that enables us to obtain the flow velocity vector from conventional color Doppler velocity data on the range of interest at any phase of cardiac cycle without angle dependency. We investigated whether the flow velocity vector obtained at LV outflow tract (LVOT) in late Systole had a relation with IF and invasively obtained LV relaxation parameters. Method: Study subjects were consecutive 26 patients who underwent diagnostic cardiac catheterization and conventional color Doppler imaging on the same day. Color Doppler image was acquired in the apical 3-chamber view. The analyses for flow velocity vector were performed offline using an echo image analyzer. The late systolic velocity of the blood flowing was obtained as an average value of the L VOT (V LVOT −late Systole). LV pressure was obtained using a catheter-tipped micromanometer. From the recorded pressure waves, first derivative of LV pressure (dP/dt) and a time constant τ of LV pressure decay during isovolumic relaxation were calculated. From LV pressure-dP/dt relationships (phase loop), IF was determined. Results: A significant positive correlation was observed between the V LVOT -late Systole and IF (r=0.75, p LVOT -late Systole also had significant correlations both with peak negative dP/dt (r=0.49, p Conclusion: This study indicates that the V LVOT -late Systole, which may be a noninvasive substitute for IF, has significant correlations with the parameters of LV relaxation. Echodynamography is a new useful technique to estimate LV early diastolic function.