心肌桥冠状动脉血流显像与冠状动脉内多普勒检测对照分析

Assessment of coronary flow of myocardial bridging using coronary flow imaging in comparison with intracoronary Doppler

目的与冠状动脉内多普勒(ICD)对照,分析冠状动脉血流显像(CFI)测量前降支心肌桥冠状动脉血流频谱特征和血流速度储备(CFVR)变化。方法冠状动脉造影、冠状动脉血管内超声和ICD检查确诊为冠状动脉左前降支心肌桥且无明显狭窄患者9例(心肌桥组)和健康者9例(对照组),利用CFI检测基础状态和经静脉注射腺苷140μg·kg-1·min-1达到最大充血反应状态时冠状动脉左前降支血流,分别通过舒张期最大峰值血流速度(PDV)、舒张期平均血流速度(MDV)和平均峰值血流速度(APV)计算冠状动脉血流速度储备。与ICD测值相比较,分析CFI方法的准确性。结果CFI测量心肌桥组和对照组冠状动脉前降支中远端血流,心肌桥组中6例CFI频谱表现为"拇指征",其测值与ICD测值的回归方程分别为y1=0.54x+1.22、y2=0.55x+1.08和y=0.87x+0.39,相关系数r分别为0.65、0.70和0.81(P<0.01)。与对照组比较,冠状动脉血流速度参数中年龄和基础状态的差异无统计学意义;心肌桥组最大充血反应状态冠状动脉血流速度参数明显低于对照组,CFVR亦明显低于对照组,均有统计学差异。结论CFI是一项准确测量CFVR的方法,通过舒张期平均血流速度计算CFVR,测值准确且简便,可广泛用于临床;CFVR的减低,可能是导致心肌桥患者心绞痛的原因之一。

Objective To analyze coronary flow spectral features and coronary flow velocity reserve （CFVR） changes of anterior descending myocardial bridging（MB） by coronary flow imaging （CFI）, compared with intracoronary Doppler （ICD）. Methods Nine patients with myocardial bridging in the coronary left anterior descending （LAD） without significant stenosis, diagnosed by coronary angiography （CA）, coronary intravascular ultrasotmd （IVUS）, and intracoronary Doppler （ICD）, were analyzed. The LAD flow veloci- ties were measured by CFI at basehne and hyperemic conditions （ intravenous administration of adenosine 140 μg· kg^-1· min^-1 ）, diastolic peak flow velocity （PDV）, average diastolic flow velocity （MDV）and average peak velocity （APV） were applied to calculate coronary flow velocity reserve （ CFVR）. Compared with the measurements of intracoronary Doppler （ICD）, the accuracy of CFI was analyzed. Nine cases without significant coronary stenosis served as control group. Results Flow velocities were measured by CFI in the middle - distal anterior descending coronary artery in both MB group and control group. CFI spectrum appeared as ＂finger tip＂ in 6 cases in MB group. CFVR calculated by PDV, MDV, and APV well correlated with those measured by ICD respectively（regression equation： y1 = 0.54x1 ＋ 1.22, y2 = 0.55x2 ＋ 1.08 and y3 = 0.87x3 ＋ 0.39; correlation coefficient： r2 = 0.65, r2 = 0.70 and r3 = 0.81, p 〈 0.01）. There was no significant difference of coronary flow velocity both at baseline and ages of patients between the two groups. The coronary flow velocities in hyperemic conditions were signitlcantly lower in the MB group than in the control group. CFVR were also signiticantly lower in the MB group than in the control group. Conclusion CFI is an accurate method for assessment of CFVR. The CFVR calculated by MDV are accurate, concise, and convenient. This method can be widely used in clinic. Decreased CFVR of patients with MB may be one of the causes of angina pectoris.