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Three-dimensional reconstruction of flow jets in prosthetic mitral valves: An in vitro pulsatile flow study
Journal o f the American Society o f Eclrocardiography Volume 9 N u m b e r 3
7C
THREE-DIMENSIONAL RECONSTRUCTION OF FLOW JETS IN PROSTHETIC MITRAL VALVES: AN IN VITRO PULSATILE FLOW STUDY Tsui-Lieh Hsa MD, Hsing-Wen Sung Phl), Mu-Jen Chiang BSc, Pei-Shin Yu BSc, Jen-Her Lu MD, Shih-Pu Wang MD, Mau-Song Chang M D Veterans General Hospital-Taipei and Department of Chemical Engineering, National Central University, Taiwan, Republic of China
Abstracts
Oral Abstract Session C7 Congenital Echocardiography C7A
THE PROGNOSTIC SIGNIFICANCE OF A POSITIVE DOBUTAMINE STRESS ECHOCARDIOGRAM IN PEDIATRIC HEART TRANSPLANT PATIENTS Thomas R. Kimball, MD, Sandra A. Witt,RDCS. Applied Echocardiography Research Laboratory, Children's Hospital, Cincinnati, OH Accelerated coronary artery disease (TxCAD) is the leading cause of death after the first year of heart transplant. Since arteriography has been shown to seriously underestimate the extent of allograft coronary artery disease we have performed dobutamine stress echocardiography (DSE) to detect TxCAD. We sought to determine the predictive value of a positive DSE. "Fentransplant patients (1-17 y.o.) underwent DSE using a modified adult protocol. Coronary insufficiency was diagnosed by the presence of regional wall motion abnormalities during DSE. Cardiac events and anglo and intracoronary ultrasound (IVUS) results have been monitored during follow-up (6-24mos). Results: Six of the 10 patients had no evidence of ischemia (Group 1=no ischemia) by DSE. All 6 continue to show no evidence of coronary artery disease during F/U. Four of the 10 patients had ischemia (Group 2=ischemia) by DSE. One Group 2 patient also had positive angio simultaneously, and was started on aggressive medical management and now has a negative DSE. The IVUS and anglo of 2 other Group 2 patients became positive only recently (20 mos. after initial positive DSE). Both patients are now receiving aggressive medical treatment. The anglo and IVUS of the fourth Group 2 patient became positive 3 months after DSE. This patient developed an anginal variant and heart failure and underwent re-transplant. Patholoqy of the diseased heart showed >95% occlusion of all 3 coronary arteries. In all 4 Group 2 patients DSE was the first indication of the presence of anatomically significant TXCAD. AlI of these patients later developed evidence for TxCAD by angio, IVUS, and/or pathology. We conclude that a positive DSE in pediatric heart transplant patients carries an unfavorable prognosis.
C7B
IDENTIFICATION OF PATIENTS WITH KAWASAKI DISEASE AT RISK FOR MYOCARDIAL ISCHEMIA WITH DOBUTAMINE STRESS ECHOCARDIOGRAPHY Thomas R. Kimball, MD, Sandra A. Witt, RDCS. Applied Echocardiography Research Laboratory, Chilcren's Hospital, Cincinnati, OH Coronary artery aneurysms occur in approximately 10-20% of patients with Kawasaki disease. Currently, angiography is used to monitor progressive changes from aneurysms to stenotic lesions. However, the physiologic significance of these lesions is unknown, making it difficult to determine when restriction of activity or surgical intervention should occur. We have previously shown that dobutamine stress echocardiography (DSE) is safe and effective in children. The aim of this study was to determine the role of DSE in identifying Kawasaki patients that are at risk for myocardial ischemia. DSE was performed in 14 Kawasaki patients with aneurysms (3 - 20.5 y.o.) using a modified adult protocol. Ischemia was diagnosed if a regional wall motion abnormality developed. Cardiac events in all patients have been recorded during follow-up (3-18 months). Results: DSE was normal in 12 of the 14 patients (Group 1=no ischemia). There have been no cardiac events during FlU in 11 of the 12 Group 1 patients. The remaining Group 1 patient was referred to surgery as a conservative approach despite a normal physiologic response to stress and extensive collateralization secondary to near occlusion of the left anterior descending coronary artery and only 30% narrowing of the right coronary artery. Ischemia was evident by DSE in 2 of the 14 patients (Group 2=isehemia). In one, angina has subsequently developed during FlU. The parents refuse surgery, and the patient is on calcium channel blockers, warfarin, and aspirin. In the other Group 2 patient, bypass grafting was performed and repeat DSE is now normal. We conclude that DSE identifies Kawasaki patients at risk for myocardial ischemia. DSE can be used in patients with aneurysms to determine risk for myocardial ischemia allowing for improved medical management and surgicN timing.
This study was designed to characterize the 3-dimensional(3D) flow profile in prosthetic mitral valves and to examine the variability of mnltiplane 2dimensional(2D) color Doppler flow images(CDF]). Seven prosthetic mitral valves (porcine, pericardial, Start-Edwards caged-ball, caged-disc, BjorkShiley and Medtronic-Hall tilting disc and St. Jude Medical bileafiet valves) with various geometric configurations were evaluated in an in vitro pulse duplicator system. Sequential 2D CDFI were acquired using rotational scanning. Volume-rendered 3D reconstruction of distal and proximal flow jets were performed by dedicated software. Multiplane 2-D CDFI findings were correlated with 3-D flow jets orientation. In the distal 3D flow maps, for the caged ball and caged disc prostheses, a circumferential flow eminated around the ball and disc were demonstrated. However, only two narrow peripheral jets were observed in all the 2D planes imaged. For the tilting disc valves, two eccentric jets with different volume emerging from the major and minor orifices were seen in 3D maps However, only one jet from the major or minor orifice was imaged as the 2D imaging plmle was parallel to the disc. For the bileaflet valve, three central jets with smaller one in the center were observed. The number of jets in 2D CDFI may vary in different planes. For the bioprosthetic valves, 3D images of distal flow showed a star-shape central jet configuration. In the proximal 3D flow maps, regurgitant jets were imaged for the tilting disc, bileaflet and pericardial valves. However the number and direction of the regurgitant jets might vary during the rotation of the 2D imaging plane. The proximal convergence zone could be imaged in all of the mitral prosthesis with various shape. We concluded that the 2D flow maps may vau, according to the angle of the imaged plane. Three-D reconstruction of proximal and distal flow jets provide better understanding the flow dynamics in prosthetic heart valves.
7D
AORTIC REGURGITATION FLOW VOLUME AND RATE CAN BE RELIABLY QUANTIFIED BY 3-D ECHOCARDIOGRAPHIC MEASUREMENT OF COLOR DOPPLER AR JET VOLUME Philippe Acar MD, Michael Jones MD, Takahiro Shiota MD, Alain Delabays MD, Izumi Yamada MD, David Sahn MD, Natesa Pandian MD.
Tufts-New EnglandMedical Center, Boston, MA NIH-LAMS, Bethesda, MD, Oregon Health Sciences University, Portland, OR. While 2-D echo and color Doppler (CD) is useful in the qualitative assessment of aortic regurgitation (AR), 2D CD is unable quantify of AR flow volume (V) because of the complex geometry of AR jets. We hypothesized that measurement of the actual 3D V of CD AR jets would correlate with true AR flow V and rates and thus could quantify AR severity. To assess this, we performed volume-rendered 3-D echo (3DE) in 6 sheep with surgically induced chronic AR. We obtained a total of 22 different states of AR by altering load. Instantaneous AR flow V were obtained by aortic and pulmonary electromagnetic flow meters (EFM). With an ATL/Interspec CD scanner interfaced to a 3DE system (TomTec), AR was imaged using rotational scanning. We acquired 2D CD images of aliased AR jets at every 1 degree (0-180) and performed 3DE reconstructions. We measured AR jet areas in 10-12 paraplane images, derived 3D V of the AR jets and correlated them with EMF flow data. We also compared conventional 2D CD AR jet areas to EMF AR V. Results (Mean+SD): 3DE displayed the AR jets of complex shapes and sizes in multiple views. By EMF, AR flow rate varied from 0.14 to 3.1 I/min; AR V ranged 1 to 34 ml/beat (12+8). 3DE measured V of AR jet was 13+7 ml/beat (range 3-30 ml). While the correlation between max area of AR jet by 2D CD correlated poorly with EMF AR V (r=.34, p=NS ), 3DE AR let V had an excellent correlation with AR V by EMF: y=.77x+3.6, r=.92, p<.O001. Bland-Altman analysis showed a mean difference of only 0.71+3.3 mi/beat. Conclusion: Dynamic 3DE can allow appraisal of the true 3D geometry of AR jets and quantification of AR volumes.
369
7C
THREE-DIMENSIONAL RECONSTRUCTION OF FLOW JETS IN PROSTHETIC MITRAL VALVES: AN IN VITRO PULSATILE FLOW STUDY Tsui-Lieh Hsa MD, Hsing-Wen Sung Phl), Mu-Jen Chiang BSc, Pei-Shin Yu BSc, Jen-Her Lu MD, Shih-Pu Wang MD, Mau-Song Chang M D Veterans General Hospital-Taipei and Department of Chemical Engineering, National Central University, Taiwan, Republic of China
Abstracts
Oral Abstract Session C7 Congenital Echocardiography C7A
THE PROGNOSTIC SIGNIFICANCE OF A POSITIVE DOBUTAMINE STRESS ECHOCARDIOGRAM IN PEDIATRIC HEART TRANSPLANT PATIENTS Thomas R. Kimball, MD, Sandra A. Witt,RDCS. Applied Echocardiography Research Laboratory, Children's Hospital, Cincinnati, OH Accelerated coronary artery disease (TxCAD) is the leading cause of death after the first year of heart transplant. Since arteriography has been shown to seriously underestimate the extent of allograft coronary artery disease we have performed dobutamine stress echocardiography (DSE) to detect TxCAD. We sought to determine the predictive value of a positive DSE. "Fentransplant patients (1-17 y.o.) underwent DSE using a modified adult protocol. Coronary insufficiency was diagnosed by the presence of regional wall motion abnormalities during DSE. Cardiac events and anglo and intracoronary ultrasound (IVUS) results have been monitored during follow-up (6-24mos). Results: Six of the 10 patients had no evidence of ischemia (Group 1=no ischemia) by DSE. All 6 continue to show no evidence of coronary artery disease during F/U. Four of the 10 patients had ischemia (Group 2=ischemia) by DSE. One Group 2 patient also had positive angio simultaneously, and was started on aggressive medical management and now has a negative DSE. The IVUS and anglo of 2 other Group 2 patients became positive only recently (20 mos. after initial positive DSE). Both patients are now receiving aggressive medical treatment. The anglo and IVUS of the fourth Group 2 patient became positive 3 months after DSE. This patient developed an anginal variant and heart failure and underwent re-transplant. Patholoqy of the diseased heart showed >95% occlusion of all 3 coronary arteries. In all 4 Group 2 patients DSE was the first indication of the presence of anatomically significant TXCAD. AlI of these patients later developed evidence for TxCAD by angio, IVUS, and/or pathology. We conclude that a positive DSE in pediatric heart transplant patients carries an unfavorable prognosis.
C7B
IDENTIFICATION OF PATIENTS WITH KAWASAKI DISEASE AT RISK FOR MYOCARDIAL ISCHEMIA WITH DOBUTAMINE STRESS ECHOCARDIOGRAPHY Thomas R. Kimball, MD, Sandra A. Witt, RDCS. Applied Echocardiography Research Laboratory, Chilcren's Hospital, Cincinnati, OH Coronary artery aneurysms occur in approximately 10-20% of patients with Kawasaki disease. Currently, angiography is used to monitor progressive changes from aneurysms to stenotic lesions. However, the physiologic significance of these lesions is unknown, making it difficult to determine when restriction of activity or surgical intervention should occur. We have previously shown that dobutamine stress echocardiography (DSE) is safe and effective in children. The aim of this study was to determine the role of DSE in identifying Kawasaki patients that are at risk for myocardial ischemia. DSE was performed in 14 Kawasaki patients with aneurysms (3 - 20.5 y.o.) using a modified adult protocol. Ischemia was diagnosed if a regional wall motion abnormality developed. Cardiac events in all patients have been recorded during follow-up (3-18 months). Results: DSE was normal in 12 of the 14 patients (Group 1=no ischemia). There have been no cardiac events during FlU in 11 of the 12 Group 1 patients. The remaining Group 1 patient was referred to surgery as a conservative approach despite a normal physiologic response to stress and extensive collateralization secondary to near occlusion of the left anterior descending coronary artery and only 30% narrowing of the right coronary artery. Ischemia was evident by DSE in 2 of the 14 patients (Group 2=isehemia). In one, angina has subsequently developed during FlU. The parents refuse surgery, and the patient is on calcium channel blockers, warfarin, and aspirin. In the other Group 2 patient, bypass grafting was performed and repeat DSE is now normal. We conclude that DSE identifies Kawasaki patients at risk for myocardial ischemia. DSE can be used in patients with aneurysms to determine risk for myocardial ischemia allowing for improved medical management and surgicN timing.
This study was designed to characterize the 3-dimensional(3D) flow profile in prosthetic mitral valves and to examine the variability of mnltiplane 2dimensional(2D) color Doppler flow images(CDF]). Seven prosthetic mitral valves (porcine, pericardial, Start-Edwards caged-ball, caged-disc, BjorkShiley and Medtronic-Hall tilting disc and St. Jude Medical bileafiet valves) with various geometric configurations were evaluated in an in vitro pulse duplicator system. Sequential 2D CDFI were acquired using rotational scanning. Volume-rendered 3D reconstruction of distal and proximal flow jets were performed by dedicated software. Multiplane 2-D CDFI findings were correlated with 3-D flow jets orientation. In the distal 3D flow maps, for the caged ball and caged disc prostheses, a circumferential flow eminated around the ball and disc were demonstrated. However, only two narrow peripheral jets were observed in all the 2D planes imaged. For the tilting disc valves, two eccentric jets with different volume emerging from the major and minor orifices were seen in 3D maps However, only one jet from the major or minor orifice was imaged as the 2D imaging plmle was parallel to the disc. For the bileaflet valve, three central jets with smaller one in the center were observed. The number of jets in 2D CDFI may vary in different planes. For the bioprosthetic valves, 3D images of distal flow showed a star-shape central jet configuration. In the proximal 3D flow maps, regurgitant jets were imaged for the tilting disc, bileaflet and pericardial valves. However the number and direction of the regurgitant jets might vary during the rotation of the 2D imaging plane. The proximal convergence zone could be imaged in all of the mitral prosthesis with various shape. We concluded that the 2D flow maps may vau, according to the angle of the imaged plane. Three-D reconstruction of proximal and distal flow jets provide better understanding the flow dynamics in prosthetic heart valves.
7D
AORTIC REGURGITATION FLOW VOLUME AND RATE CAN BE RELIABLY QUANTIFIED BY 3-D ECHOCARDIOGRAPHIC MEASUREMENT OF COLOR DOPPLER AR JET VOLUME Philippe Acar MD, Michael Jones MD, Takahiro Shiota MD, Alain Delabays MD, Izumi Yamada MD, David Sahn MD, Natesa Pandian MD.
Tufts-New EnglandMedical Center, Boston, MA NIH-LAMS, Bethesda, MD, Oregon Health Sciences University, Portland, OR. While 2-D echo and color Doppler (CD) is useful in the qualitative assessment of aortic regurgitation (AR), 2D CD is unable quantify of AR flow volume (V) because of the complex geometry of AR jets. We hypothesized that measurement of the actual 3D V of CD AR jets would correlate with true AR flow V and rates and thus could quantify AR severity. To assess this, we performed volume-rendered 3-D echo (3DE) in 6 sheep with surgically induced chronic AR. We obtained a total of 22 different states of AR by altering load. Instantaneous AR flow V were obtained by aortic and pulmonary electromagnetic flow meters (EFM). With an ATL/Interspec CD scanner interfaced to a 3DE system (TomTec), AR was imaged using rotational scanning. We acquired 2D CD images of aliased AR jets at every 1 degree (0-180) and performed 3DE reconstructions. We measured AR jet areas in 10-12 paraplane images, derived 3D V of the AR jets and correlated them with EMF flow data. We also compared conventional 2D CD AR jet areas to EMF AR V. Results (Mean+SD): 3DE displayed the AR jets of complex shapes and sizes in multiple views. By EMF, AR flow rate varied from 0.14 to 3.1 I/min; AR V ranged 1 to 34 ml/beat (12+8). 3DE measured V of AR jet was 13+7 ml/beat (range 3-30 ml). While the correlation between max area of AR jet by 2D CD correlated poorly with EMF AR V (r=.34, p=NS ), 3DE AR let V had an excellent correlation with AR V by EMF: y=.77x+3.6, r=.92, p<.O001. Bland-Altman analysis showed a mean difference of only 0.71+3.3 mi/beat. Conclusion: Dynamic 3DE can allow appraisal of the true 3D geometry of AR jets and quantification of AR volumes.
369