Hozumi T, Yoshida K, Ogata Y, Akasaka T, Asami Y, Takagi T, Morioka S
Division of Cardiology, Kobe General Hospital, Japan.
Circulation. 1998 Apr 28;97(16):1557-62. doi: 10.1161/01.cir.97.16.1557.
Coronary flow reserve has been considered an important diagnostic index of the functional significance of coronary artery stenosis. With Doppler technique, it has been assessed as the ratio of hyperemic to basal coronary flow velocity (coronary flow velocity reserve [CFVR]) by invasive or semiinvasive methods with a Doppler catheter, a Doppler guide wire, and a transesophageal Doppler echocardiographic probe. Recent technological advancement in transthoracic Doppler echocardiography (TTDE) provides measurement of coronary flow velocity in the distal portion of the left anterior descending coronary artery (LAD) and may be useful in the noninvasive CFVR measurement. The purpose of this study was to evaluate the value of CFVR determined by TTDE for the assessment of significant LAD stenosis.
We studied 36 patients who underwent coronary angiography for the assessment of coronary artery disease. The study population consisted of 12 patients with significant LAD stenosis (group A) and 24 patients without significant LAD stenosis (group B). With TTDE, coronary flow velocities in the distal LAD were recorded at rest and during hyperemia induced by intravenous infusion of adenosine (0.14 mg x kg(-1) x min(-1)) under the guidance of color Doppler flow mapping. Adequate spectral Doppler recordings of coronary flow in the distal LAD for the assessment of CFVR were obtained in 34 of 36 study patients (94%). The peak and mean diastolic coronary flow velocities at baseline did not differ between groups A and B (23.6+/-10.3 versus 22.9+/-6.6 cm/s and 16.4+/-8.6 versus 14.5+/-4.0 cm/s, respectively). However, the peak and mean coronary flow velocities during hyperemia in group A were significantly smaller than those in group B (35.6+/-16.3 versus 54.2+/-16.3 cm/s and 24.7+/-13.1 versus 37.9+/-13.0 cm/s, respectively; P<.01). There were significant differences in CFVR obtained from peak and mean diastolic velocity between groups A and B (1.5+/-0.2 versus 2.4+/-0.4 and 1.5+/-0.2 versus 2.6+/-0.4, respectively; P<.001). A CFVR from peak diastolic velocity <2.0 had a sensitivity of 92% and a specificity of 82% for the presence of significant LAD stenosis. A CFVR from mean diastolic velocity <2.0 had a sensitivity of 92% and a specificity of 86% for the presence of significant LAD stenosis.
CFVR determined by TTDE is useful in the noninvasive assessment of significant stenotic lesion in the LAD.
冠状动脉血流储备一直被视为冠状动脉狭窄功能意义的重要诊断指标。借助多普勒技术，通过使用多普勒导管、多普勒导丝和经食管多普勒超声心动图探头的有创或半有创方法，将其评估为充血期与基础冠状动脉血流速度之比（冠状动脉血流速度储备[CFVR]）。经胸多普勒超声心动图（TTDE）的最新技术进展可测量左前降支冠状动脉（LAD）远端的冠状动脉血流速度，可能有助于无创性CFVR测量。本研究的目的是评估TTDE测定的CFVR对评估LAD明显狭窄的价值。
我们研究了36例因评估冠状动脉疾病而接受冠状动脉造影的患者。研究人群包括12例LAD明显狭窄患者（A组）和24例LAD无明显狭窄患者（B组）。采用TTDE，在彩色多普勒血流图引导下，记录静息状态及静脉输注腺苷（0.14 mg·kg⁻¹·min⁻¹）诱发充血期间LAD远端的冠状动脉血流速度。36例研究患者中有34例（94%）获得了用于评估CFVR的LAD远端冠状动脉血流的充分频谱多普勒记录。A组和B组基线时舒张期冠状动脉血流速度峰值和平均值无差异（分别为23.6±10.3与22.9±6.6 cm/s以及16.4±8.6与14.5±4.0 cm/s）。然而，A组充血期冠状动脉血流速度峰值和平均值显著低于B组（分别为35.6±16.3与54.2±16.3 cm/s以及24.7±13.1与37.9±13.0 cm/s；P<0.01）。A组和B组从舒张期速度峰值和平均值获得的CFVR存在显著差异（分别为1.5±0.2与2.4±0.4以及1.5±0.2与2.6±0.4；P<0.001）。舒张期速度峰值CFVR<2.0对存在明显LAD狭窄的敏感性为92%，特异性为82%。舒张期平均速度CFVR<2.0对存在明显LAD狭窄的敏感性为92%，特异性为86%。
TTDE测定的CFVR有助于无创评估LAD明显狭窄病变。
