Resarch topics

Evaluating a Vascular Endothelial Function

Medical engineering group

We proposed a method to evaluate the endothelial function based on the expansion rate of the integrated air cuff plethysmogram measured using the oscillometric method. This method is not affected by blood pressure fluctuations and can be used to rapidly evaluate endothelial function. In this study, the expansion rate of the integrated air cuff plethysmogram was simulated to confirm that the proposed method is suitable for assessing changes in arterial compliance associated with endothelial function. Simulation results show that this technique can be used to evaluate changes in arterial viscoelastic characterisitics. We then compared the proposed expansion rate of the integrated air cuff plethysmogram and percent flow mediated vasodilation (% FMD) (the standard indicator used to evaluate endothelial function) and obtained a correlation of r = 0.589 (p<0.05). Furthermore, in order to verify the effectiveness in determining the risk of arteriosclerosis, a receiver operation characteristic (ROC) analysis was performed. The results showed that the area under the curve (AUC) of the proposed index is 0.914, which is above the% FMD value. Therefore, the proposed method has potential for clinical use.


1.Noninvasive evaluation of endothelial function based on dilation rate of integrated air-cuff plethysmogram (in Japanese)
Toshio Tsuji, Tiji Ukawa, Ryosuke Kubo, Harutoyo Hirano, Yuichi Kurita, Tsuneo Takayanagi, Haruka Morimoto, Naomi Idei, Yukihito Higashi, Ryuji Nakamura, Noboru Saeki, Masashi Kawamoto, and Masao Yoshizumi
The Japanese Journal of Physical Therapy Science, Vol. 82, No. 3, pp. 259-266, Jun. 2012.

2.Novel Non-invasive Method of Measurement of Endothelial Function: Enclosed-Zone Flow-Mediated Dilatation (ezFMD), Teiji Ukawa, Tsuneo Takayanagi, Haruka Morimoto, Yukihito Higashi, Naomi Idei, Masao Yoshizumi, and Toshio Tsuji, Medical and Biological Engineering and Computing,Vol. 50, No. 12, pp. 1239-1247, 2012.

3.A novel noninvasive and simple method for assessment of endothelial function: Enclosed zone flow-mediated vasodilation (ezFMD) using an oscillation amplitude measurement, Naomi Idei, Teiji Ukawa, Masato Kajikawa, Yumiko Iwamoto, Noritaka Fujimura, Tatsuya Maruhashi, Shinsuke Mikami, Takeshi Matsumoto, Yasuki Kihara, Kazuaki Chayama, Kensuke Noma, Ayumu Nakashima, Tsuneo Takayanagi, Haruka Morimoto, Toshio Tsuji, and Yukihito Higashi, Atherosclerosis, Volume 229, Issue 2, pp. 324-330, August 2013.

4.Endothelial Function Assessed by Automatic Measurement of Enclosed Zone Flow-mediated Vasodilation Using an Oscillometric Method Is an Independent Predictor of Cardiovascular Events, Haruka Morimoto, Masato Kajikawa, Nozomu Oda, Naomi Idei, Harutoyo Hirano, Eisuke Hida, Tatsuya Maruhashi, Yumiko Iwamoto, Shinji Kishimoto, Shogo Matsui, Yoshiki Aibara, Takayuki Hidaka, Yasuki Kihara, Kazuaki Chayama, Chikara Goto, Kensuke Noma, Ayumu Nakashima, Teiji Ukawa, Toshio Tsuji, and Yukihito Higashi, Journal of the American Heart Association (JAHA), 5(12). pii: e004385. doi: 10.1161/JAHA.116.004385., 2016 Dec 21 (SCI, IF=5.117).