Chiho Morita1, Takaaki Nakatsu2, Shozo Kusachi3, Tomoki Kitawaki4, Shinichi Usui4, Kazuo Tobe5, Shinji Toyonaga2, Hiroko Ogawa1, Satoshi Hirohata1, Yasushi Shiratori1. 1. Department of Medicine and Medical Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. 2. Department of Cardiology, Kagawa-ken Saiseikai Hospital, Kagawa, Japan. 3. Department of Medical Technology, Okayama University Graduate School of Health Sciences, 2-5-1 Shikata-cho, Okayama, 700-8558, Japan. sh-ksc56@po1.oninet.ne.jp. 4. Department of Medical Technology, Okayama University Graduate School of Health Sciences, 2-5-1 Shikata-cho, Okayama, 700-8558, Japan. 5. Health and Medical Section, Health and Environmental Center, Okayama University, Okayama, Japan.
Abstract
PURPOSE: Automatic Doppler flow signal detection systems can provide beat-to-beat information for large blood vessels. We have developed new equipment for automatic measurement of Doppler flow signals. The reliability of the system was examined, and the variability of aortic and pulmonary peak flow velocity was determined. METHODS: We measured peak flow velocity using a newly developed system in healthy volunteers and patients with atrial fibrillation. Analysis of variability of peak flow velocity was performed with maximal entropy methods. RESULTS: In Bland-Altman plots, the mean and standard deviation (SD) of differences in aortic peak flow velocities between the automatic and manual measurements were 0.22 ± 0.75 cm/s and 0.85 ± 0.38 cm/s, respectively, in five normal volunteers. Moreover, less than 5% of the plotted points were beyond ± 2 SD of the differences. Furthermore, good reproducibility was demonstrated using Bland-Altman plots and Pearson's correlation analysis. Identical reliability was obtained in patients with atrial fibrillation. The same results were obtained for pulmonary peak flow velocity. In five healthy subjects, aortic and pulmonary peak flow showed standard deviations of 7.2 ± 2.4 and 3.8 ± 0.6 cm/s, respectively, and coefficients of variation of 6.1% ± 1.0% and 5.1% ± 1.1%, respectively, in time-domain variability. Similarly, frequency-domain variability was obtained for both peak flow velocities. CONCLUSION: The present study demonstrated the reliability of a newly developed automatic Doppler flow signal detection system. Using this system, the present study demonstrated for the first time aortic and pulmonary peak flow velocity variability. The present analytical methods may have considerable potential for studying aortic and/or pulmonary flow variability in connection with cardiac performance and prognosis of cardiac disease.
PURPOSE: Automatic Doppler flow signal detection systems can provide beat-to-beat information for large blood vessels. We have developed new equipment for automatic measurement of Doppler flow signals. The reliability of the system was examined, and the variability of aortic and pulmonary peak flow velocity was determined. METHODS: We measured peak flow velocity using a newly developed system in healthy volunteers and patients with atrial fibrillation. Analysis of variability of peak flow velocity was performed with maximal entropy methods. RESULTS: In Bland-Altman plots, the mean and standard deviation (SD) of differences in aortic peak flow velocities between the automatic and manual measurements were 0.22 ± 0.75 cm/s and 0.85 ± 0.38 cm/s, respectively, in five normal volunteers. Moreover, less than 5% of the plotted points were beyond ± 2 SD of the differences. Furthermore, good reproducibility was demonstrated using Bland-Altman plots and Pearson's correlation analysis. Identical reliability was obtained in patients with atrial fibrillation. The same results were obtained for pulmonary peak flow velocity. In five healthy subjects, aortic and pulmonary peak flow showed standard deviations of 7.2 ± 2.4 and 3.8 ± 0.6 cm/s, respectively, and coefficients of variation of 6.1% ± 1.0% and 5.1% ± 1.1%, respectively, in time-domain variability. Similarly, frequency-domain variability was obtained for both peak flow velocities. CONCLUSION: The present study demonstrated the reliability of a newly developed automatic Doppler flow signal detection system. Using this system, the present study demonstrated for the first time aortic and pulmonary peak flow velocity variability. The present analytical methods may have considerable potential for studying aortic and/or pulmonary flow variability in connection with cardiac performance and prognosis of cardiac disease.
Authors: Y Sawada; N Ohtomo; Y Tanaka; G Tanaka; K Yamakoshi; S Terachi; K Shimamoto; M Nakagawa; S Satoh; S Kuroda; O Iimura Journal: Med Biol Eng Comput Date: 1997-07 Impact factor: 2.602
Authors: K Otsuka; S Murakami; Y Kubo; T Yamanaka; G Mitsutake; S Ohkawa; K Matsubayashi; S Yano; G Cornélissen; F Halberg Journal: Biomed Pharmacother Date: 2003-10 Impact factor: 6.529