Haude M, Caspari G, Baumgart D, Ehring T, Schulz R, Roth T, Koch L, Erbel R, Spiller P, Heusch G
Department of Cardiology, University-GHS Essen, Germany.
Basic Res Cardiol. 2000 Jun;95(3):261-70. doi: 10.1007/s003950050189.
The evaluation of regional myocardial blood flow (RMBF) during cardiac catheterization is of particular diagnostic interest. The purpose of this investigation was to validate x-ray densitometric parameters for the evaluation of RMBF. In five anesthetized dogs, arterial flow in the circumflex coronary artery was measured continuously with an electromagnetic flowmeter, and RMBF was determined by colored microspheres. Five different perfusion levels were created by mechanical obstruction of the coronary artery or by intravenous infusion of adenosine. At each steady-state perfusion level, digital subtraction coronary angiograms were obtained for densitometric analysis. Results documented a close correlation between the related time parameters 1/Mean Transit Time (1/MTT, r2 = 0.969), and 1/Rise Time (1/RT, r2 = 0.965) and RMBF over a wide range between 0.36 ml/(min x g) and 11.16 ml/(min x g). Maximum myocardial contrast density (Imax) also showed a good, but inverse correlation (r2 = 0.889) with RMBF and, therefore, did not reflect vascular volume. Contrast medium Appearance Time (AT) showed no correlation to RMBF (r2 = 0.017). Repeat densitometric measurements for different perfusion levels revealed a good reproducibility for MTT (accuracy: 0.001 s; precision: 0.447 s or 6.7 %) and RT (accuracy: 0.014 s; precision: 0.202 s or 10.4 %), while AT (accuracy: 0.072 s; precision: 0.420 s or 68.5%) and Imax (accuracy: 0.022 GL; precision: 1.197 GL or 44.5%) showed substantial variation. Myocardial perfusion reserve (MPR) calculated from RT (r2 = 0.90) or MTT (r2 = 0.94) showed better correlations to RMBF reserve than MPR calculated from AT (r2 = 0.04). In conclusion, only 1/MTT and 1/RT showed a good reproducibility and a close correlation to RMBF. Therefore, only these parameters can be recommended for calculations of RMBF and its reserve under clinical conditions.
在心脏导管插入术期间评估局部心肌血流量（RMBF）具有特殊的诊断意义。本研究的目的是验证用于评估RMBF的X射线密度测定参数。在五只麻醉的狗中，用电磁流量计连续测量回旋支冠状动脉中的动脉血流量，并通过彩色微球测定RMBF。通过冠状动脉的机械阻塞或静脉注射腺苷创建五种不同的灌注水平。在每个稳态灌注水平下，获取数字减法冠状动脉血管造影以进行密度测定分析。结果表明，在0.36 ml/（min×g）至11.16 ml/（min×g）的宽范围内，相关时间参数1/平均通过时间（1/MTT，r2 = 0.969）和1/上升时间（1/RT，r2 = 0.965）与RMBF之间存在密切相关性。最大心肌对比密度（Imax）也与RMBF呈现良好但相反的相关性（r2 = 0.889），因此不能反映血管容积。对比剂出现时间（AT）与RMBF无相关性（r2 = 0.017）。对不同灌注水平进行重复密度测定显示，MTT（准确度：0.001 s；精密度：0.447 s或6.7%）和RT（准确度：0.014 s；精密度：0.202 s或10.4%）具有良好的可重复性，而AT（准确度：0.072 s；精密度：0.420 s或68.5%）和Imax（准确度：0.022 GL；精密度：1.197 GL或44.5%）显示出较大变化。由RT（r2 = 0.90）或MTT（r2 = 0.94）计算得出的心肌灌注储备（MPR）与RMBF储备的相关性优于由AT计算得出的MPR（r2 = 0.04）。总之，只有1/MTT和1/RT具有良好的可重复性且与RMBF密切相关。因此，在临床条件下，只有这些参数可推荐用于计算RMBF及其储备。
