Derumeaux G, Ovize M, Loufoua J, André-Fouet X, Minaire Y, Cribier A, Letac B
Départment de Cardiologie, Hôpital Charles Nicolle, Centre Hospitalier Universitaire de Rouen, France.
Circulation. 1998 May 19;97(19):1970-7. doi: 10.1161/01.cir.97.19.1970.
Quantification of regional myocardial function is a major unresolved issue in cardiology. We evaluated the accuracy of pulsed Doppler tissue imaging (DTI), a new echocardiographic technique, to quantify regional myocardial dysfunction induced by acute ischemia and reperfusion.
In nine open-chest anesthetized pigs, various degrees of regional wall motion abnormalities were induced by graded reduction of left anterior descending coronary artery (LAD) blood flow. Pulsed Doppler tissue imaging was performed from an epicardial apical four-chamber view with the sample placed within the middle part of the septal wall. Peak septal velocities were calculated during systole, isovolumic relaxation, and early and late diastole. Regional myocardial blood flow and systolic and diastolic dysfunctions were assessed by radioactive microspheres and ultrasonic crystals, respectively. Ischemia resulted in a significant rapid reduction of systolic velocities and an early decrease in the ratio of early to late diastolic velocities. Both changes were detected by pulsed DTI within 5 seconds of coronary artery occlusion. The decrease in systolic velocity significantly correlated with both systolic shortening (r=.90, P<.0001) and regional myocardial blood flow (r=.96, P<.0001) during reduction of LAD blood flow.
These results suggest that DTI may be a promising new tool for the quantification of ischemia-induced regional myocardial dysfunction.
局部心肌功能的量化是心脏病学中一个尚未解决的主要问题。我们评估了一种新的超声心动图技术——脉冲多普勒组织成像（DTI），用于量化急性缺血和再灌注诱导的局部心肌功能障碍的准确性。
在9只开胸麻醉的猪中，通过逐渐减少左前降支冠状动脉（LAD）血流诱导出不同程度的局部室壁运动异常。从心外膜心尖四腔视图进行脉冲多普勒组织成像，样本置于室间隔壁中部。计算收缩期、等容舒张期、舒张早期和晚期的室间隔峰值速度。分别通过放射性微球和超声晶体评估局部心肌血流以及收缩和舒张功能障碍。缺血导致收缩期速度显著快速降低，舒张早期与晚期速度之比早期下降。在冠状动脉闭塞5秒内，脉冲DTI检测到了这两种变化。在减少LAD血流期间，收缩期速度的降低与收缩期缩短（r = 0.90，P <.0001）和局部心肌血流（r = 0.96，P <.0001）均显著相关。
这些结果表明，DTI可能是一种用于量化缺血诱导的局部心肌功能障碍的有前景的新工具。
