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Junichi Yoshikawa - One of the best experts on this subject based on the ideXlab platform.
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physiologic assessment of Coronary Artery Stenosis by Coronary flow reserve measurements with transthoracic doppler echocardiography comparison with exercise thallium 201 single photon emission computed tomography
Journal of the American College of Cardiology, 2001Co-Authors: Masao Daimon, Hiroyuki Watanabe, Hiroyuki Yamagishi, Takashi Muro, Kaname Akioka, Kumiko Hirata, Kazuhide Takeuchi, Junichi YoshikawaAbstract:OBJECTIVES: We evaluated the value of Coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of Coronary Artery Stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT). BACKGROUND: Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending Coronary Artery (LAD) Stenosis. However, discrepancies exist between angiographic and physiologic estimates of Coronary lesion severity. METHODS: We studied 36 patients suspected of having Coronary Artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201-SPECT. RESULTS: Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201-SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value +/- SD) were 1.5 +/- 0.6 and 1.5 +/- 0.7 in group A and 2.8 +/- 0.8 and 2.7 +/- 0.7 in group B, respectively. Both peak and mean CFR < or = 2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively. CONCLUSIONS: Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201-SPECT for physiologic estimation of the severity of LAD Stenosis.
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physiologic assessment of Coronary Artery Stenosis by Coronary flow reserve measurements with transthoracic doppler echocardiography comparison with exercise thallium 201 single photon emission computed tomography
Journal of the American College of Cardiology, 2001Co-Authors: Masao Daimon, Hiroyuki Watanabe, Hiroyuki Yamagishi, Takashi Muro, Kaname Akioka, Kumiko Hirata, Kazuhide Takeuchi, Junichi YoshikawaAbstract:Abstract OBJECTIVES We evaluated the value of Coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of Coronary Artery Stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT). BACKGROUND Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending Coronary Artery (LAD) Stenosis. However, discrepancies exist between angiographic and physiologic estimates of Coronary lesion severity. METHODS We studied 36 patients suspected of having Coronary Artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201–SPECT. RESULTS Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201–SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value ± SD) were 1.5 ± 0.6 and 1.5 ± 0.7 in group A and 2.8 ± 0.8 and 2.7 ± 0.7 in group B, respectively. Both peak and mean CFR ≤2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively. CONCLUSIONS Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201–SPECT for physiologic estimation of the severity of LAD Stenosis.
Lewis C Becker - One of the best experts on this subject based on the ideXlab platform.
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assessment of severity of Coronary Artery Stenosis in a canine model using the pet agent 18f fluorobenzyl triphenyl phosphonium comparison with 99mtc tetrofosmin
The Journal of Nuclear Medicine, 2007Co-Authors: Igal Madar, Hayden T Ravert, Antony Dipaula, Robert F Dannals, Lewis C BeckerAbstract:Myocardial perfusion imaging plays an important role in clinical management of Coronary Artery disease, but the most commonly used radionuclides significantly underestimate the severity of Coronary Artery Stenosis. The objective of this study was to evaluate the potential clinical utility of the PET compound 18F-fluorobenzyl triphenyl phosphonium (18F-FBnTP) and characterize its capacity to assess the severity of Coronary Artery Stenosis in a canine model in vivo and ex vivo. Methods:18F-FBnTP myocardial uptake was measured in 17 dogs with various degrees of Stenosis of the left anterior descending (LAD) or circumflex (LCx) Coronary arteries during adenosine vasodilation, using dynamic PET and γ-well counting. True myocardial blood flow in ischemic (IS) and nonischemic (NIS) beds of the left ventricle was determined with radioactive microspheres. 18F-FBnTP and 99mTc-tetrofosmin activities were compared in 8 dogs ex vivo. Results: The quantitative assessment of the perfusion defect was significantly (P
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assessment of severity of Coronary Artery Stenosis in a canine model using the pet agent 18f fluorobenzyl triphenyl phosphonium comparison with 99mtc tetrofosmin
The Journal of Nuclear Medicine, 2007Co-Authors: Igal Madar, Hayden T Ravert, Antony Dipaula, Robert F Dannals, Lewis C BeckerAbstract:Myocardial perfusion imaging plays an important role in clinical management of Coronary Artery disease, but the most commonly used radionuclides significantly underestimate the severity of Coronary Artery Stenosis. The objective of this study was to evaluate the potential clinical utility of the PET compound 18 F-fluorobenzyl triphenyl phosphonium ( 18 F-FBnTP) and characterize its capacity to assess the severity of Coronary Artery Stenosis in a canine model in vivo and ex vivo. Methods: 18 F-FBnTP myocardial uptake was measured in 17 dogs with various degrees of Stenosis of the left anterior descending (LAD) or circumflex (LCx) Coronary arteries during adenosine vasodilation, using dynamic PET and γ-well counting. True myocardial blood flow in ischemic (IS) and nonischemic (NIS) beds of the left ventricle was determined with radioactive microspheres. 18 F-FBnTP and 99m Tc-tetrofosmin activities were compared in 8 dogs ex vivo. Results: The quantitative assessment of the perfusion defect was significantly (P < 0.03) more accurate with 18 F-FBnTP than with 99m Tc-tetrofosmin, in mild (IS/NIS; 0.72 ± 0.08, 0.93 ± 0.07, respectively, mean ± SE) and severe Stenosis (0.42 ± 0.05, 0.64 ± 0.08, respectively), compared with microsphere flow (mild, 0.43 ± 0.06; severe, 0.22 ± 0.04). The IS/NIS ratio of both radionuclides correlated linearly with microsphere flow disparity with a similar slope. Flow defect contrast was 2.7 times greater for 18 F-FBnTP than for 99m Tc-tetrofosmin, as inferred from the regression line intercept (0.14 vs. 0.38, respectively). The 18 F-FBnTP PET IS/NIS ratio (mild, 0.70 ± 0.04; severe, 0.46 ± 0.02), did not differ statistically (P≥0.330) from that measured ex vivo. A nearly identical qualitative and quantitative estimate of Stenosis severity was obtained by early, short (5-15-min) and delayed, prolonged (30-60-min) 18 F-FBnTP PET scans. The stenotic area measured by PET was 16% smaller than that defined by tissue staining. Conclusion: 18 F-FBnTP PET is a promising new technology for rapid noninvasive detection and assessment of perfusion defect severity in the myocardium.
Masao Daimon - One of the best experts on this subject based on the ideXlab platform.
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prediction of Coronary Artery Stenosis at rest in patients with normal left ventricular wall motion segmental analyses using strain imaging diastolic index
International Heart Journal, 2013Co-Authors: Bei Yang, Masao Daimon, Katsuhisa Ishii, Takayuki Kawata, Sakiko Miyazaki, Kuniaki Hirose, Ryoko Ichikawa, Shuo Ju Chiang, Hiromasa Suzuki, Katsumi MiyauchiAbstract:Noninvasive detection of Coronary Artery Stenosis usually requires a stress test in patients without left ventricular (LV) regional wall motion abnormalities (RWMA). In contrast, abnormal regional LV relaxation caused by ischemia may persist beyond recovery from transient ischemia. The aim of the present study was to determine whether segmental analysis of abnormal regional LV relaxation using the strain imaging diastolic index (SI-DI) at rest could predict Coronary Artery Stenosis in the three major vessels in patients without LV dysfunction or RWMA. We performed 2D speckle tracking echocardiography and Coronary angiography in 85 patients without RWMA with suspected Coronary Artery disease. Patients with LV dysfunction or acute Coronary syndrome were excluded. Echocardiographic images of the LV were obtained in the apical 2-, 3-, and 4-chamber views and divided into 6 segments. In each segment, SI-DI derived from transverse strain imaging was determined. Forty-eight patients had significant Coronary Artery Stenosis (≥ 70%). The optimal cutoff values of SI-DI were 60.5% in the mid anteroseptal segment for detecting left anterior descending Artery Stenosis (sensitivity, 83.3%; specificity, 81.1%), 60.5% in the basal anterolateral segment for detecting left circumflex Artery Stenosis (sensitivity, 80.9%; specificity, 90.3%), and 61.5% in the basal inferior segment for detecting right Coronary Artery Stenosis (sensitivity, 74.1%; specificity, 77.8%). A segmental analysis of SI-DI at rest predicted Coronary Artery Stenosis in the three major vessels in patients without RWMA. This noninvasive method may be useful for detecting Coronary Artery Stenosis without a stress test.
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physiologic assessment of Coronary Artery Stenosis by Coronary flow reserve measurements with transthoracic doppler echocardiography comparison with exercise thallium 201 single photon emission computed tomography
Journal of the American College of Cardiology, 2001Co-Authors: Masao Daimon, Hiroyuki Watanabe, Hiroyuki Yamagishi, Takashi Muro, Kaname Akioka, Kumiko Hirata, Kazuhide Takeuchi, Junichi YoshikawaAbstract:OBJECTIVES: We evaluated the value of Coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of Coronary Artery Stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT). BACKGROUND: Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending Coronary Artery (LAD) Stenosis. However, discrepancies exist between angiographic and physiologic estimates of Coronary lesion severity. METHODS: We studied 36 patients suspected of having Coronary Artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201-SPECT. RESULTS: Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201-SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value +/- SD) were 1.5 +/- 0.6 and 1.5 +/- 0.7 in group A and 2.8 +/- 0.8 and 2.7 +/- 0.7 in group B, respectively. Both peak and mean CFR < or = 2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively. CONCLUSIONS: Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201-SPECT for physiologic estimation of the severity of LAD Stenosis.
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physiologic assessment of Coronary Artery Stenosis by Coronary flow reserve measurements with transthoracic doppler echocardiography comparison with exercise thallium 201 single photon emission computed tomography
Journal of the American College of Cardiology, 2001Co-Authors: Masao Daimon, Hiroyuki Watanabe, Hiroyuki Yamagishi, Takashi Muro, Kaname Akioka, Kumiko Hirata, Kazuhide Takeuchi, Junichi YoshikawaAbstract:Abstract OBJECTIVES We evaluated the value of Coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of Coronary Artery Stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT). BACKGROUND Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending Coronary Artery (LAD) Stenosis. However, discrepancies exist between angiographic and physiologic estimates of Coronary lesion severity. METHODS We studied 36 patients suspected of having Coronary Artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201–SPECT. RESULTS Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201–SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value ± SD) were 1.5 ± 0.6 and 1.5 ± 0.7 in group A and 2.8 ± 0.8 and 2.7 ± 0.7 in group B, respectively. Both peak and mean CFR ≤2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively. CONCLUSIONS Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201–SPECT for physiologic estimation of the severity of LAD Stenosis.
Igal Madar - One of the best experts on this subject based on the ideXlab platform.
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assessment of severity of Coronary Artery Stenosis in a canine model using the pet agent 18f fluorobenzyl triphenyl phosphonium comparison with 99mtc tetrofosmin
The Journal of Nuclear Medicine, 2007Co-Authors: Igal Madar, Hayden T Ravert, Antony Dipaula, Robert F Dannals, Lewis C BeckerAbstract:Myocardial perfusion imaging plays an important role in clinical management of Coronary Artery disease, but the most commonly used radionuclides significantly underestimate the severity of Coronary Artery Stenosis. The objective of this study was to evaluate the potential clinical utility of the PET compound 18F-fluorobenzyl triphenyl phosphonium (18F-FBnTP) and characterize its capacity to assess the severity of Coronary Artery Stenosis in a canine model in vivo and ex vivo. Methods:18F-FBnTP myocardial uptake was measured in 17 dogs with various degrees of Stenosis of the left anterior descending (LAD) or circumflex (LCx) Coronary arteries during adenosine vasodilation, using dynamic PET and γ-well counting. True myocardial blood flow in ischemic (IS) and nonischemic (NIS) beds of the left ventricle was determined with radioactive microspheres. 18F-FBnTP and 99mTc-tetrofosmin activities were compared in 8 dogs ex vivo. Results: The quantitative assessment of the perfusion defect was significantly (P
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assessment of severity of Coronary Artery Stenosis in a canine model using the pet agent 18f fluorobenzyl triphenyl phosphonium comparison with 99mtc tetrofosmin
The Journal of Nuclear Medicine, 2007Co-Authors: Igal Madar, Hayden T Ravert, Antony Dipaula, Robert F Dannals, Lewis C BeckerAbstract:Myocardial perfusion imaging plays an important role in clinical management of Coronary Artery disease, but the most commonly used radionuclides significantly underestimate the severity of Coronary Artery Stenosis. The objective of this study was to evaluate the potential clinical utility of the PET compound 18 F-fluorobenzyl triphenyl phosphonium ( 18 F-FBnTP) and characterize its capacity to assess the severity of Coronary Artery Stenosis in a canine model in vivo and ex vivo. Methods: 18 F-FBnTP myocardial uptake was measured in 17 dogs with various degrees of Stenosis of the left anterior descending (LAD) or circumflex (LCx) Coronary arteries during adenosine vasodilation, using dynamic PET and γ-well counting. True myocardial blood flow in ischemic (IS) and nonischemic (NIS) beds of the left ventricle was determined with radioactive microspheres. 18 F-FBnTP and 99m Tc-tetrofosmin activities were compared in 8 dogs ex vivo. Results: The quantitative assessment of the perfusion defect was significantly (P < 0.03) more accurate with 18 F-FBnTP than with 99m Tc-tetrofosmin, in mild (IS/NIS; 0.72 ± 0.08, 0.93 ± 0.07, respectively, mean ± SE) and severe Stenosis (0.42 ± 0.05, 0.64 ± 0.08, respectively), compared with microsphere flow (mild, 0.43 ± 0.06; severe, 0.22 ± 0.04). The IS/NIS ratio of both radionuclides correlated linearly with microsphere flow disparity with a similar slope. Flow defect contrast was 2.7 times greater for 18 F-FBnTP than for 99m Tc-tetrofosmin, as inferred from the regression line intercept (0.14 vs. 0.38, respectively). The 18 F-FBnTP PET IS/NIS ratio (mild, 0.70 ± 0.04; severe, 0.46 ± 0.02), did not differ statistically (P≥0.330) from that measured ex vivo. A nearly identical qualitative and quantitative estimate of Stenosis severity was obtained by early, short (5-15-min) and delayed, prolonged (30-60-min) 18 F-FBnTP PET scans. The stenotic area measured by PET was 16% smaller than that defined by tissue staining. Conclusion: 18 F-FBnTP PET is a promising new technology for rapid noninvasive detection and assessment of perfusion defect severity in the myocardium.
Hiroyuki Yamagishi - One of the best experts on this subject based on the ideXlab platform.
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physiologic assessment of Coronary Artery Stenosis by Coronary flow reserve measurements with transthoracic doppler echocardiography comparison with exercise thallium 201 single photon emission computed tomography
Journal of the American College of Cardiology, 2001Co-Authors: Masao Daimon, Hiroyuki Watanabe, Hiroyuki Yamagishi, Takashi Muro, Kaname Akioka, Kumiko Hirata, Kazuhide Takeuchi, Junichi YoshikawaAbstract:OBJECTIVES: We evaluated the value of Coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of Coronary Artery Stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT). BACKGROUND: Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending Coronary Artery (LAD) Stenosis. However, discrepancies exist between angiographic and physiologic estimates of Coronary lesion severity. METHODS: We studied 36 patients suspected of having Coronary Artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201-SPECT. RESULTS: Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201-SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value +/- SD) were 1.5 +/- 0.6 and 1.5 +/- 0.7 in group A and 2.8 +/- 0.8 and 2.7 +/- 0.7 in group B, respectively. Both peak and mean CFR < or = 2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively. CONCLUSIONS: Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201-SPECT for physiologic estimation of the severity of LAD Stenosis.
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physiologic assessment of Coronary Artery Stenosis by Coronary flow reserve measurements with transthoracic doppler echocardiography comparison with exercise thallium 201 single photon emission computed tomography
Journal of the American College of Cardiology, 2001Co-Authors: Masao Daimon, Hiroyuki Watanabe, Hiroyuki Yamagishi, Takashi Muro, Kaname Akioka, Kumiko Hirata, Kazuhide Takeuchi, Junichi YoshikawaAbstract:Abstract OBJECTIVES We evaluated the value of Coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of Coronary Artery Stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT). BACKGROUND Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending Coronary Artery (LAD) Stenosis. However, discrepancies exist between angiographic and physiologic estimates of Coronary lesion severity. METHODS We studied 36 patients suspected of having Coronary Artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201–SPECT. RESULTS Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201–SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value ± SD) were 1.5 ± 0.6 and 1.5 ± 0.7 in group A and 2.8 ± 0.8 and 2.7 ± 0.7 in group B, respectively. Both peak and mean CFR ≤2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively. CONCLUSIONS Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201–SPECT for physiologic estimation of the severity of LAD Stenosis.