The Experts below are selected from a list of 14643 Experts worldwide ranked by ideXlab platform
Ajit P Yoganathan - One of the best experts on this subject based on the ideXlab platform.
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Quantitative Evaluation of Annuloplasty on Mitral Valve Chordae Tendineae Forces to Supplement Surgical Planning Model Development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts ( N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets ( N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation ( p
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quantitative evaluation of Annuloplasty on mitral valve chordae tendineae forces to supplement surgical planning model development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts (N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets (N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation (p < .05). Compared to the IMR condition, increasing levels of downsized Annuloplasty significantly reduced regurgitation, increased coaptation, reduced posteromedial papillary muscle strut chordal forces, and reduced intermediary chordal forces from the anterolateral papillary muscle (p < .05). These results provide for the first time a novel comprehensive data set for refining the ability of computational MV models to simulate IMR and varying sizes of complete rigid ring Annuloplasty.
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saddle shaped mitral valve Annuloplasty rings experience lower forces compared with flat rings
Circulation, 2008Co-Authors: Morten O. Jensen, Hans Nygaard, H Jensen, Morten Smerup, Robert A Levine, Ajit P Yoganathan, Michael J Hasenkam, Sten Lyager NielsenAbstract:Background— New insight into the 3D dynamic behavior of the mitral valve has prompted a reevaluation of Annuloplasty ring designs. Force balance analysis indicates correlation between annulus forces and stresses in leaflets and chords. Improving this stress distribution can intuitively enhance the durability of mitral valve repair. We tested the hypothesis that saddle-shaped Annuloplasty rings have superior uniform systolic force distribution compared with a nonuniform force distribution in flat Annuloplasty rings. Methods and Results— Sixteen 80-kg pigs had a flat (n=8) or saddle-shaped (n=8) mitral Annuloplasty ring implanted. Mitral annulus 3D dynamic geometry was obtained with sonomicrometry before ring insertion. Strain gauges mounted on dedicated D-shaped rigid flat and saddle-shaped Annuloplasty rings provided the intraoperative force distribution perpendicular to the annular plane. Average systolic annular height to commissural width ratio before ring implantation was 14.0%±1.6%. After flat and sa...
Andrew W Siefert - One of the best experts on this subject based on the ideXlab platform.
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Quantitative Evaluation of Annuloplasty on Mitral Valve Chordae Tendineae Forces to Supplement Surgical Planning Model Development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts ( N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets ( N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation ( p
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quantitative evaluation of Annuloplasty on mitral valve chordae tendineae forces to supplement surgical planning model development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts (N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets (N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation (p < .05). Compared to the IMR condition, increasing levels of downsized Annuloplasty significantly reduced regurgitation, increased coaptation, reduced posteromedial papillary muscle strut chordal forces, and reduced intermediary chordal forces from the anterolateral papillary muscle (p < .05). These results provide for the first time a novel comprehensive data set for refining the ability of computational MV models to simulate IMR and varying sizes of complete rigid ring Annuloplasty.
Muralidhar Padala - One of the best experts on this subject based on the ideXlab platform.
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Hemodynamic outcomes after undersizing ring Annuloplasty and focal suture Annuloplasty for surgical repair of functional tricuspid regurgitation
The Journal of thoracic and cardiovascular surgery, 2020Co-Authors: Alan Amedi, Daisuke Onohara, Kirthana Sreerangathama Suresh, Muralidhar PadalaAbstract:OBJECTIVE Surgical Annuloplasty for functional tricuspid regurgitation (FTR) is on the rise and can be performed in several ways with varied outcomes. In this study, we sought to compare the hemodynamic outcomes of tricuspid Annuloplasty performed with a commercially available Annuloplasty ring (tricuspid valve Annuloplasty [TVA]) compared with focal suture Annuloplasty (Hetzer) in an experimental FTR model. METHODS An ex vivo FTR model was developed by inducing right ventricular dilatation by acute afterload elevation, causing severe tricuspid valve tethering and annular dilatation, leading to regurgitation. Ten porcine hearts in which FTR was induced underwent TVA with a 26-mm Edwards MC3 ring and Hetzer Annuloplasty with a pledgeted suture cinching the anteroposterior and septal annulus. FTR was measured before after each repair, and tenting geometry, valve kinematics, and subvalvular geometry were measured with echocardiography. RESULTS At baseline, none of the hearts had FTR, but upon afterload elevation an FTR volume of 17.7 ± 9.2 mL (26.38 ± 17.47% regurgitant fraction) was measured (P
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hemodynamic outcomes after undersizing ring Annuloplasty and focal suture Annuloplasty for surgical repair of functional tricuspid regurgitation
The Journal of Thoracic and Cardiovascular Surgery, 2020Co-Authors: Alan Amedi, Daisuke Onohara, Kirthana Sreerangathama Suresh, Muralidhar PadalaAbstract:OBJECTIVE Surgical Annuloplasty for functional tricuspid regurgitation (FTR) is on the rise and can be performed in several ways with varied outcomes. In this study, we sought to compare the hemodynamic outcomes of tricuspid Annuloplasty performed with a commercially available Annuloplasty ring (tricuspid valve Annuloplasty [TVA]) compared with focal suture Annuloplasty (Hetzer) in an experimental FTR model. METHODS An ex vivo FTR model was developed by inducing right ventricular dilatation by acute afterload elevation, causing severe tricuspid valve tethering and annular dilatation, leading to regurgitation. Ten porcine hearts in which FTR was induced underwent TVA with a 26-mm Edwards MC3 ring and Hetzer Annuloplasty with a pledgeted suture cinching the anteroposterior and septal annulus. FTR was measured before after each repair, and tenting geometry, valve kinematics, and subvalvular geometry were measured with echocardiography. RESULTS At baseline, none of the hearts had FTR, but upon afterload elevation an FTR volume of 17.7 ± 9.2 mL (26.38 ± 17.47% regurgitant fraction) was measured (P < .0001). TVA reduced regurgitation by 50% and Hetzer Annuloplasty by 56% , respectively, but both left persistent FTR. Anteroseptal tenting area was 279.0 ± 158.9 mm2 before repair and decreased significantly to 147.2 ± 134.8 mm2 (P = .0195) with Hetzer but not with TVA. Posteroseptal tenting area was 425.1 ± 169.2 mm2 before repair and was significantly reduced by both techniques (TVA: 200.3 ± 102.9 mm2 [P = .0012]; Hetzer: 237.6 ± 127.6 mm2 [P = .0270]). CONCLUSIONS Tricuspid Annuloplasty with a ring or a focal suture can reduce FTR but not eliminate it. Annular approaches did not relieve tricuspid valve tethering and reduced leaflet mobility persisted. Either subannular repairs or judicious use of valve replacement may be necessary.
Eric L Pierce - One of the best experts on this subject based on the ideXlab platform.
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Quantitative Evaluation of Annuloplasty on Mitral Valve Chordae Tendineae Forces to Supplement Surgical Planning Model Development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts ( N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets ( N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation ( p
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quantitative evaluation of Annuloplasty on mitral valve chordae tendineae forces to supplement surgical planning model development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts (N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets (N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation (p < .05). Compared to the IMR condition, increasing levels of downsized Annuloplasty significantly reduced regurgitation, increased coaptation, reduced posteromedial papillary muscle strut chordal forces, and reduced intermediary chordal forces from the anterolateral papillary muscle (p < .05). These results provide for the first time a novel comprehensive data set for refining the ability of computational MV models to simulate IMR and varying sizes of complete rigid ring Annuloplasty.
Jeanpierre Rabbah - One of the best experts on this subject based on the ideXlab platform.
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Quantitative Evaluation of Annuloplasty on Mitral Valve Chordae Tendineae Forces to Supplement Surgical Planning Model Development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts ( N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets ( N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation ( p
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quantitative evaluation of Annuloplasty on mitral valve chordae tendineae forces to supplement surgical planning model development
Cardiovascular Engineering and Technology, 2014Co-Authors: Andrew W Siefert, Jeanpierre Rabbah, Eric L Pierce, Karyn S Kunzelman, Ajit P YoganathanAbstract:Computational models of the heart’s mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical Annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral Annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae. MVs were excised from ovine hearts (N = 15) and mounted in a pulsatile heart simulator which has been demonstrated to mimic the systolic MV geometry and coaptation of healthy and chronic IMR sheep. Strut and intermediary chordae from both MV leaflets (N = 4) were instrumented with force transducers. Tested conditions included a healthy control, IMR, oversized Annuloplasty, true-sized Annuloplasty, and undersized mitral Annuloplasty. A2-P2 leaflet coaptation length, regurgitation, and chordal tethering were quantified and statistically compared across experimental conditions. MR was successfully simulated with significant increases in MR, tethering forces for each of the chordae, and decrease in leaflet coaptation (p < .05). Compared to the IMR condition, increasing levels of downsized Annuloplasty significantly reduced regurgitation, increased coaptation, reduced posteromedial papillary muscle strut chordal forces, and reduced intermediary chordal forces from the anterolateral papillary muscle (p < .05). These results provide for the first time a novel comprehensive data set for refining the ability of computational MV models to simulate IMR and varying sizes of complete rigid ring Annuloplasty.