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Satoshi Nakatani - One of the best experts on this subject based on the ideXlab platform.

  • compensatory increase of left atrial external work to left ventricular dysfunction caused by afterload increase
    American Journal of Physiology-heart and Circulatory Physiology, 2015
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Satoshi Nakatani
    Abstract:

    Afterload mismatch can cause acute decompensation leading to an occurrence of acute heart failure. We investigated how the left atrium (LA) and left ventricle (LV) react to acute increases in afterload using speckle tracking echocardiography (STE). LA strain and volume were obtained by STE in 10 dogs during banding of descending aorta (AoB). Simultaneously, LA pressure was measured by a micromanometer-tipped catheter. LA peak negative strain during LA contraction, strain change during LA relaxation (early reservoir strain), and that during LA dilatation (late reservoir strain) were obtained from LA longitudinal strain-volume curves. From pressure-strain curves, the areas of A-loop and V-loops were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work). AoB increased LV systolic pressure (105 ± 15 vs. 163 ± 12 mmHg, P < 0.01) and mean LA pressure (3.8 ± 1.2 vs. 7.1 ± 2.0 mmHg, P < 0.01). LV global circumferential strain decreased (-18.8 ± 3.5 vs. -13.2 ± 3.5%, P < 0.01), but LV stroke volume was maintained (8.4 ± 2.3 vs. 9.6 ± 3.6 ml). LA peak negative strain (-2.9 ± 2.3 vs. -9.8 ± 4.0%, P < 0.01) and early reservoir strain (4.5 ± 2.1 vs. 7.7 ± 2.4%, P < 0.05) increased by AoB, but late reservoir strain did not change (8.9 ± 3.4 vs. 6.1 ± 3.4%). A-work significantly increased (3.2 ± 2.0 vs. 19.2 ± 15.1 mmHg %, P < 0.01), whereas V-work did not change (13.3 ± 7.1 vs. 13.1 ± 7.7 mmHg %). In conclusion, LA external work during active contraction and relaxation increased as compensation for LV dysfunction during aortic banding. Atrial dysfunction may lead failure of this mechanism and hemodynamic decompensation.

  • abstract 12325 compensatory increase of left atrial external work to left ventricular dysfunction during afterload increase insights into the mechanism of decompensation in heart failure with preserved ejection fraction
    Circulation, 2014
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Masamichi Oka, Koichiro Kotani, Satoshi Nakatani
    Abstract:

    Introduction: Afterload mismatch is considered as a cause of acute decompensation in patients with heart failure with preserved ejection fraction (HFPEF). However, behaviors of left atrium (LA) and ventricle (LV) to afterload increase have not been fully elucidated. We investigated how LA and LV acted to acute increase in afterload using speckle tracking echocardiography. Methods: Serial echocardiographic and hemodynamic data were acquired in 10 dogs during banding of the descending aorta (AoB). LA pressure was measured by a micromanometer via left pulmonary vein. As shown in Figure, peak negative strain during LA contraction and strain change during LA relaxation (early reservoir strain) and that during systole (late reservoir strain) were generated by simultaneous acquisition of LA longitudinal strain and volume. Pressure-strain curve showed 2 loops (A-loop, V-loop) and areas in A-loop and V-loop were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work), respectively. Results: AoB increased LV systolic pressure by about 60 mmHg, mean LA pressure (3.8±1.3 vs. 7.1±2.0 mmHg) and LV end-diastolic pressure (4.5±1.7 vs. 10.7±4.0 mmHg, all p < 0.01). LV global circumferential strain decreased (-18.8±3.5 vs. -13.2±3.5%, p < 0.01) but LV stroke volume was maintained (8.4±2.3 vs. 9.6±3.6 ml). LA peak negative strain (-2.9±2.3 vs. -9.8±4.0%, p < 0.01) and early reservoir strain (3.4±1.1 vs. 7.8±2.6%, p < 0.01) increased substantially by AoB, but late reservoir function did not change (9.3±3.5 vs. 6.1±2.0%). A-work significantly increased (3.2±2.0 to 19.2±15.1 mmHg %, p < 0.01), while V-work did not change (13.3±7.1 vs. 13.6±8.0 mmHg %). Conclusions: During aortic banding, LA contraction, early reservoir function and thereby external work during the phase increased as a compensation to LV dysfunction. The failure of this mechanism may lead to decompensation in HFPEF. ![][1] [1]: /embed/graphic-1.gif

Katsuji Inoue - One of the best experts on this subject based on the ideXlab platform.

  • compensatory increase of left atrial external work to left ventricular dysfunction caused by afterload increase
    American Journal of Physiology-heart and Circulatory Physiology, 2015
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Satoshi Nakatani
    Abstract:

    Afterload mismatch can cause acute decompensation leading to an occurrence of acute heart failure. We investigated how the left atrium (LA) and left ventricle (LV) react to acute increases in afterload using speckle tracking echocardiography (STE). LA strain and volume were obtained by STE in 10 dogs during banding of descending aorta (AoB). Simultaneously, LA pressure was measured by a micromanometer-tipped catheter. LA peak negative strain during LA contraction, strain change during LA relaxation (early reservoir strain), and that during LA dilatation (late reservoir strain) were obtained from LA longitudinal strain-volume curves. From pressure-strain curves, the areas of A-loop and V-loops were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work). AoB increased LV systolic pressure (105 ± 15 vs. 163 ± 12 mmHg, P < 0.01) and mean LA pressure (3.8 ± 1.2 vs. 7.1 ± 2.0 mmHg, P < 0.01). LV global circumferential strain decreased (-18.8 ± 3.5 vs. -13.2 ± 3.5%, P < 0.01), but LV stroke volume was maintained (8.4 ± 2.3 vs. 9.6 ± 3.6 ml). LA peak negative strain (-2.9 ± 2.3 vs. -9.8 ± 4.0%, P < 0.01) and early reservoir strain (4.5 ± 2.1 vs. 7.7 ± 2.4%, P < 0.05) increased by AoB, but late reservoir strain did not change (8.9 ± 3.4 vs. 6.1 ± 3.4%). A-work significantly increased (3.2 ± 2.0 vs. 19.2 ± 15.1 mmHg %, P < 0.01), whereas V-work did not change (13.3 ± 7.1 vs. 13.1 ± 7.7 mmHg %). In conclusion, LA external work during active contraction and relaxation increased as compensation for LV dysfunction during aortic banding. Atrial dysfunction may lead failure of this mechanism and hemodynamic decompensation.

  • abstract 12325 compensatory increase of left atrial external work to left ventricular dysfunction during afterload increase insights into the mechanism of decompensation in heart failure with preserved ejection fraction
    Circulation, 2014
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Masamichi Oka, Koichiro Kotani, Satoshi Nakatani
    Abstract:

    Introduction: Afterload mismatch is considered as a cause of acute decompensation in patients with heart failure with preserved ejection fraction (HFPEF). However, behaviors of left atrium (LA) and ventricle (LV) to afterload increase have not been fully elucidated. We investigated how LA and LV acted to acute increase in afterload using speckle tracking echocardiography. Methods: Serial echocardiographic and hemodynamic data were acquired in 10 dogs during banding of the descending aorta (AoB). LA pressure was measured by a micromanometer via left pulmonary vein. As shown in Figure, peak negative strain during LA contraction and strain change during LA relaxation (early reservoir strain) and that during systole (late reservoir strain) were generated by simultaneous acquisition of LA longitudinal strain and volume. Pressure-strain curve showed 2 loops (A-loop, V-loop) and areas in A-loop and V-loop were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work), respectively. Results: AoB increased LV systolic pressure by about 60 mmHg, mean LA pressure (3.8±1.3 vs. 7.1±2.0 mmHg) and LV end-diastolic pressure (4.5±1.7 vs. 10.7±4.0 mmHg, all p < 0.01). LV global circumferential strain decreased (-18.8±3.5 vs. -13.2±3.5%, p < 0.01) but LV stroke volume was maintained (8.4±2.3 vs. 9.6±3.6 ml). LA peak negative strain (-2.9±2.3 vs. -9.8±4.0%, p < 0.01) and early reservoir strain (3.4±1.1 vs. 7.8±2.6%, p < 0.01) increased substantially by AoB, but late reservoir function did not change (9.3±3.5 vs. 6.1±2.0%). A-work significantly increased (3.2±2.0 to 19.2±15.1 mmHg %, p < 0.01), while V-work did not change (13.3±7.1 vs. 13.6±8.0 mmHg %). Conclusions: During aortic banding, LA contraction, early reservoir function and thereby external work during the phase increased as a compensation to LV dysfunction. The failure of this mechanism may lead to decompensation in HFPEF. ![][1] [1]: /embed/graphic-1.gif

Toshihiko Asanuma - One of the best experts on this subject based on the ideXlab platform.

  • compensatory increase of left atrial external work to left ventricular dysfunction caused by afterload increase
    American Journal of Physiology-heart and Circulatory Physiology, 2015
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Satoshi Nakatani
    Abstract:

    Afterload mismatch can cause acute decompensation leading to an occurrence of acute heart failure. We investigated how the left atrium (LA) and left ventricle (LV) react to acute increases in afterload using speckle tracking echocardiography (STE). LA strain and volume were obtained by STE in 10 dogs during banding of descending aorta (AoB). Simultaneously, LA pressure was measured by a micromanometer-tipped catheter. LA peak negative strain during LA contraction, strain change during LA relaxation (early reservoir strain), and that during LA dilatation (late reservoir strain) were obtained from LA longitudinal strain-volume curves. From pressure-strain curves, the areas of A-loop and V-loops were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work). AoB increased LV systolic pressure (105 ± 15 vs. 163 ± 12 mmHg, P < 0.01) and mean LA pressure (3.8 ± 1.2 vs. 7.1 ± 2.0 mmHg, P < 0.01). LV global circumferential strain decreased (-18.8 ± 3.5 vs. -13.2 ± 3.5%, P < 0.01), but LV stroke volume was maintained (8.4 ± 2.3 vs. 9.6 ± 3.6 ml). LA peak negative strain (-2.9 ± 2.3 vs. -9.8 ± 4.0%, P < 0.01) and early reservoir strain (4.5 ± 2.1 vs. 7.7 ± 2.4%, P < 0.05) increased by AoB, but late reservoir strain did not change (8.9 ± 3.4 vs. 6.1 ± 3.4%). A-work significantly increased (3.2 ± 2.0 vs. 19.2 ± 15.1 mmHg %, P < 0.01), whereas V-work did not change (13.3 ± 7.1 vs. 13.1 ± 7.7 mmHg %). In conclusion, LA external work during active contraction and relaxation increased as compensation for LV dysfunction during aortic banding. Atrial dysfunction may lead failure of this mechanism and hemodynamic decompensation.

  • abstract 12325 compensatory increase of left atrial external work to left ventricular dysfunction during afterload increase insights into the mechanism of decompensation in heart failure with preserved ejection fraction
    Circulation, 2014
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Masamichi Oka, Koichiro Kotani, Satoshi Nakatani
    Abstract:

    Introduction: Afterload mismatch is considered as a cause of acute decompensation in patients with heart failure with preserved ejection fraction (HFPEF). However, behaviors of left atrium (LA) and ventricle (LV) to afterload increase have not been fully elucidated. We investigated how LA and LV acted to acute increase in afterload using speckle tracking echocardiography. Methods: Serial echocardiographic and hemodynamic data were acquired in 10 dogs during banding of the descending aorta (AoB). LA pressure was measured by a micromanometer via left pulmonary vein. As shown in Figure, peak negative strain during LA contraction and strain change during LA relaxation (early reservoir strain) and that during systole (late reservoir strain) were generated by simultaneous acquisition of LA longitudinal strain and volume. Pressure-strain curve showed 2 loops (A-loop, V-loop) and areas in A-loop and V-loop were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work), respectively. Results: AoB increased LV systolic pressure by about 60 mmHg, mean LA pressure (3.8±1.3 vs. 7.1±2.0 mmHg) and LV end-diastolic pressure (4.5±1.7 vs. 10.7±4.0 mmHg, all p < 0.01). LV global circumferential strain decreased (-18.8±3.5 vs. -13.2±3.5%, p < 0.01) but LV stroke volume was maintained (8.4±2.3 vs. 9.6±3.6 ml). LA peak negative strain (-2.9±2.3 vs. -9.8±4.0%, p < 0.01) and early reservoir strain (3.4±1.1 vs. 7.8±2.6%, p < 0.01) increased substantially by AoB, but late reservoir function did not change (9.3±3.5 vs. 6.1±2.0%). A-work significantly increased (3.2±2.0 to 19.2±15.1 mmHg %, p < 0.01), while V-work did not change (13.3±7.1 vs. 13.6±8.0 mmHg %). Conclusions: During aortic banding, LA contraction, early reservoir function and thereby external work during the phase increased as a compensation to LV dysfunction. The failure of this mechanism may lead to decompensation in HFPEF. ![][1] [1]: /embed/graphic-1.gif

Kasumi Masuda - One of the best experts on this subject based on the ideXlab platform.

  • compensatory increase of left atrial external work to left ventricular dysfunction caused by afterload increase
    American Journal of Physiology-heart and Circulatory Physiology, 2015
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Satoshi Nakatani
    Abstract:

    Afterload mismatch can cause acute decompensation leading to an occurrence of acute heart failure. We investigated how the left atrium (LA) and left ventricle (LV) react to acute increases in afterload using speckle tracking echocardiography (STE). LA strain and volume were obtained by STE in 10 dogs during banding of descending aorta (AoB). Simultaneously, LA pressure was measured by a micromanometer-tipped catheter. LA peak negative strain during LA contraction, strain change during LA relaxation (early reservoir strain), and that during LA dilatation (late reservoir strain) were obtained from LA longitudinal strain-volume curves. From pressure-strain curves, the areas of A-loop and V-loops were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work). AoB increased LV systolic pressure (105 ± 15 vs. 163 ± 12 mmHg, P < 0.01) and mean LA pressure (3.8 ± 1.2 vs. 7.1 ± 2.0 mmHg, P < 0.01). LV global circumferential strain decreased (-18.8 ± 3.5 vs. -13.2 ± 3.5%, P < 0.01), but LV stroke volume was maintained (8.4 ± 2.3 vs. 9.6 ± 3.6 ml). LA peak negative strain (-2.9 ± 2.3 vs. -9.8 ± 4.0%, P < 0.01) and early reservoir strain (4.5 ± 2.1 vs. 7.7 ± 2.4%, P < 0.05) increased by AoB, but late reservoir strain did not change (8.9 ± 3.4 vs. 6.1 ± 3.4%). A-work significantly increased (3.2 ± 2.0 vs. 19.2 ± 15.1 mmHg %, P < 0.01), whereas V-work did not change (13.3 ± 7.1 vs. 13.1 ± 7.7 mmHg %). In conclusion, LA external work during active contraction and relaxation increased as compensation for LV dysfunction during aortic banding. Atrial dysfunction may lead failure of this mechanism and hemodynamic decompensation.

  • abstract 12325 compensatory increase of left atrial external work to left ventricular dysfunction during afterload increase insights into the mechanism of decompensation in heart failure with preserved ejection fraction
    Circulation, 2014
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Masamichi Oka, Koichiro Kotani, Satoshi Nakatani
    Abstract:

    Introduction: Afterload mismatch is considered as a cause of acute decompensation in patients with heart failure with preserved ejection fraction (HFPEF). However, behaviors of left atrium (LA) and ventricle (LV) to afterload increase have not been fully elucidated. We investigated how LA and LV acted to acute increase in afterload using speckle tracking echocardiography. Methods: Serial echocardiographic and hemodynamic data were acquired in 10 dogs during banding of the descending aorta (AoB). LA pressure was measured by a micromanometer via left pulmonary vein. As shown in Figure, peak negative strain during LA contraction and strain change during LA relaxation (early reservoir strain) and that during systole (late reservoir strain) were generated by simultaneous acquisition of LA longitudinal strain and volume. Pressure-strain curve showed 2 loops (A-loop, V-loop) and areas in A-loop and V-loop were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work), respectively. Results: AoB increased LV systolic pressure by about 60 mmHg, mean LA pressure (3.8±1.3 vs. 7.1±2.0 mmHg) and LV end-diastolic pressure (4.5±1.7 vs. 10.7±4.0 mmHg, all p < 0.01). LV global circumferential strain decreased (-18.8±3.5 vs. -13.2±3.5%, p < 0.01) but LV stroke volume was maintained (8.4±2.3 vs. 9.6±3.6 ml). LA peak negative strain (-2.9±2.3 vs. -9.8±4.0%, p < 0.01) and early reservoir strain (3.4±1.1 vs. 7.8±2.6%, p < 0.01) increased substantially by AoB, but late reservoir function did not change (9.3±3.5 vs. 6.1±2.0%). A-work significantly increased (3.2±2.0 to 19.2±15.1 mmHg %, p < 0.01), while V-work did not change (13.3±7.1 vs. 13.6±8.0 mmHg %). Conclusions: During aortic banding, LA contraction, early reservoir function and thereby external work during the phase increased as a compensation to LV dysfunction. The failure of this mechanism may lead to decompensation in HFPEF. ![][1] [1]: /embed/graphic-1.gif

Daisuke Sakurai - One of the best experts on this subject based on the ideXlab platform.

  • compensatory increase of left atrial external work to left ventricular dysfunction caused by afterload increase
    American Journal of Physiology-heart and Circulatory Physiology, 2015
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Satoshi Nakatani
    Abstract:

    Afterload mismatch can cause acute decompensation leading to an occurrence of acute heart failure. We investigated how the left atrium (LA) and left ventricle (LV) react to acute increases in afterload using speckle tracking echocardiography (STE). LA strain and volume were obtained by STE in 10 dogs during banding of descending aorta (AoB). Simultaneously, LA pressure was measured by a micromanometer-tipped catheter. LA peak negative strain during LA contraction, strain change during LA relaxation (early reservoir strain), and that during LA dilatation (late reservoir strain) were obtained from LA longitudinal strain-volume curves. From pressure-strain curves, the areas of A-loop and V-loops were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work). AoB increased LV systolic pressure (105 ± 15 vs. 163 ± 12 mmHg, P < 0.01) and mean LA pressure (3.8 ± 1.2 vs. 7.1 ± 2.0 mmHg, P < 0.01). LV global circumferential strain decreased (-18.8 ± 3.5 vs. -13.2 ± 3.5%, P < 0.01), but LV stroke volume was maintained (8.4 ± 2.3 vs. 9.6 ± 3.6 ml). LA peak negative strain (-2.9 ± 2.3 vs. -9.8 ± 4.0%, P < 0.01) and early reservoir strain (4.5 ± 2.1 vs. 7.7 ± 2.4%, P < 0.05) increased by AoB, but late reservoir strain did not change (8.9 ± 3.4 vs. 6.1 ± 3.4%). A-work significantly increased (3.2 ± 2.0 vs. 19.2 ± 15.1 mmHg %, P < 0.01), whereas V-work did not change (13.3 ± 7.1 vs. 13.1 ± 7.7 mmHg %). In conclusion, LA external work during active contraction and relaxation increased as compensation for LV dysfunction during aortic banding. Atrial dysfunction may lead failure of this mechanism and hemodynamic decompensation.

  • abstract 12325 compensatory increase of left atrial external work to left ventricular dysfunction during afterload increase insights into the mechanism of decompensation in heart failure with preserved ejection fraction
    Circulation, 2014
    Co-Authors: Katsuji Inoue, Toshihiko Asanuma, Kasumi Masuda, Daisuke Sakurai, Jitsuo Higaki, Masamichi Oka, Koichiro Kotani, Satoshi Nakatani
    Abstract:

    Introduction: Afterload mismatch is considered as a cause of acute decompensation in patients with heart failure with preserved ejection fraction (HFPEF). However, behaviors of left atrium (LA) and ventricle (LV) to afterload increase have not been fully elucidated. We investigated how LA and LV acted to acute increase in afterload using speckle tracking echocardiography. Methods: Serial echocardiographic and hemodynamic data were acquired in 10 dogs during banding of the descending aorta (AoB). LA pressure was measured by a micromanometer via left pulmonary vein. As shown in Figure, peak negative strain during LA contraction and strain change during LA relaxation (early reservoir strain) and that during systole (late reservoir strain) were generated by simultaneous acquisition of LA longitudinal strain and volume. Pressure-strain curve showed 2 loops (A-loop, V-loop) and areas in A-loop and V-loop were computed as the work during active contraction and relaxation (A-work) and that during Passive Filling and emptying (V-work), respectively. Results: AoB increased LV systolic pressure by about 60 mmHg, mean LA pressure (3.8±1.3 vs. 7.1±2.0 mmHg) and LV end-diastolic pressure (4.5±1.7 vs. 10.7±4.0 mmHg, all p < 0.01). LV global circumferential strain decreased (-18.8±3.5 vs. -13.2±3.5%, p < 0.01) but LV stroke volume was maintained (8.4±2.3 vs. 9.6±3.6 ml). LA peak negative strain (-2.9±2.3 vs. -9.8±4.0%, p < 0.01) and early reservoir strain (3.4±1.1 vs. 7.8±2.6%, p < 0.01) increased substantially by AoB, but late reservoir function did not change (9.3±3.5 vs. 6.1±2.0%). A-work significantly increased (3.2±2.0 to 19.2±15.1 mmHg %, p < 0.01), while V-work did not change (13.3±7.1 vs. 13.6±8.0 mmHg %). Conclusions: During aortic banding, LA contraction, early reservoir function and thereby external work during the phase increased as a compensation to LV dysfunction. The failure of this mechanism may lead to decompensation in HFPEF. ![][1] [1]: /embed/graphic-1.gif