Lambertz H, Tries H P, Stein T, Lethen H
Department of Cardiology, Federal Republic of Germany.
J Am Soc Echocardiogr. 1999 Mar;12(3):186-95. doi: 10.1016/s0894-7317(99)70134-3.
The feasibility of noninvasive assessment of coronary flow reserve (CFR) in the distal left anterior descending artery (LAD) with echocardiography-enhanced transthoracic pulsed wave Doppler guided by high-resolution transthoracic color Doppler (TTCD) was investigated. The results were compared with the degree of coronary diameter stenosis obtained during cardiac catheterization.
Assessment of CFR has proven to be useful in the selection of patients undergoing invasive treatment of coronary artery disease and in estimating their prognosis. However, CFR could only be determined invasively in everyday practice during catheterization procedures. Recent development of high-resolution TTCD allows transthoracic visualization of distal LAD and supra-apical intramyocardial perforator branches and noninvasive measurement of CFR with pulsed wave Doppler technique.
CFR was determined by measuring the ratio of pulsed wave Doppler time velocity integral during adenosine-induced hyperemia (140 microgram/kg/min intravenously) to baseline value. If the baseline Doppler signal of LAD flow was insufficient, an echocardiography (echo) enhancer (Levovist) was used. Forty-five patients were examined by TTCD (7-MHz B-mode, 5-MHz color Doppler, and 3.5-MHz pulsed wave Doppler) after coronary angiography had been performed. Group 1 consisted of 15 patients without heart disease, group 2 of 15 patients with 50% to 85% isolated LAD diameter stenosis, and group 3 of 15 patients with >85% LAD diameter stenosis.
Peripheral LAD coronary flow at baseline condition was assessed in 40 (88%) patients with TTCD. CFR could be quantified in 36 (80%) of the 45 patients: in 18 patients without echo enhancer, and in 18 patients with echo-enhancing agent. CFR could not be assessed in 9 (20%) patients. CFR in the various groups was as follows: group 1, 3. 13 +/- 0.57; group 2, 2.23 +/- 0.20 (vs group 1: P <.01); and group 3, 1.64 +/- 0.30 (vs group 2: P <.02).
CFR in the LAD can be determined in 80% of patients with pulsed wave Doppler guided by high-resolution TTCD combined with intravenously administered echo-enhancing agent.
研究在高分辨率经胸彩色多普勒（TTCD）引导下，采用超声心动图增强经胸脉冲波多普勒对左前降支（LAD）远端冠状动脉血流储备（CFR）进行无创评估的可行性。将结果与心导管检查时获得的冠状动脉直径狭窄程度进行比较。
CFR评估已被证明在选择接受冠状动脉疾病侵入性治疗的患者以及评估其预后方面很有用。然而，在日常实践中，CFR只能在导管插入术过程中通过侵入性方法确定。高分辨率TTCD的最新发展使得能够经胸可视化LAD远端和心尖上心肌穿支分支，并使用脉冲波多普勒技术对CFR进行无创测量。
通过测量腺苷诱发充血（静脉注射140微克/千克/分钟）期间脉冲波多普勒时间速度积分与基线值的比值来确定CFR。如果LAD血流的基线多普勒信号不足，则使用超声心动图（回声）增强剂（Levovist）。45例患者在进行冠状动脉造影后接受了TTCD检查（7兆赫B型、5兆赫彩色多普勒和3.5兆赫脉冲波多普勒）。第1组由15例无心脏病患者组成，第2组由15例LAD直径孤立狭窄50%至85%的患者组成，第3组由15例LAD直径狭窄>85%的患者组成。
40例（88%）患者通过TTCD评估了基线状态下LAD外周冠状动脉血流。45例患者中有36例（80%）可对CFR进行量化：18例未使用回声增强剂的患者，以及18例使用回声增强剂的患者。9例（20%）患者无法评估CFR。各小组的CFR如下：第1组，3.13±0.57；第2组，2.23±0.20（与第I组相比：P<.01）；第3组，1.64±0.30（与第2组相比：P<.02）。
在高分辨率TTCD联合静脉注射回声增强剂引导下，80%的患者可通过脉冲波多普勒测定LAD中的CFR。
