穂積 健之, 吉川 純一, 吉田 清, 赤阪 隆史, 赤土 正洋, 山浦 泰子, 高木 力, 三宅 仁, 八木 登志員, 前西 文秋

Takeshi HOZUMI, Jun-ichi YOSHIKAWA, Kiyoshi YOSHIDA, Takashi AKASAKA, Masahiro SHAKUDO, Yasuko YAMAURA, Tsutomu TAKAGI, Shinobu MIYAKE, Toshikazu YAGI, Fumiaki MAENISHI

神戸市立中央市民病院循環器センター内科

Department of Cardiology, Kobe General Hospital

キーワード : Doppler guide wire, Coronary artery stenosis, Continuity equation

We evaluated the usefulness of a newly developed Doppler guide wire (0.018-in) in the assessment of the stenosis severity of the coronary artery. We recorded the Doppler spectra in three kinds of rigid straight tubes of diameter 4.0 mm with different stenosis severity (50%, 62.5%, 75% diameter stenosis, 5 mm stenosis length) using pulsatile flow. The spectral peak velocity was linearly related to the flow volume from 0 to 30 (ml/min) at the proximal, stenotic, and distal sites in each tube model (r=0.98, 0.99). Using the continuity equation, we calculated the Doppler-derived % diameter stenosis from 1) the proximal-stenotic velocity ratio and 2) the distal-stenotic velocity ratio in each model at each flow rate. The Doppler-derived % diameter stenosis from proximal-stenotic velocity ratio in each model was in agreement with the real stenosis severity (48.5±1.7%, 61.3±1.5%, and 74.2±0.6%, respectively). The Doppler-derived % diameter stenosis from the distal-stenotic velocity ratio was also in agreement with the real stenosis severity (47.8±2.8%, 59.7±1.5%, and 74.7±0.5%, respectively). When we calculated the % diameter stenosis from proximal-stenotic velocity ratio, stenosis severity in the model with a side branch proximal to the stenotic site was significantly smaller than that in the model without a side branch (62.7±1.6% vs. 74.9±1.8%, p