Main M L, Escobar J F, Hall S A, Killam A L, Grayburn P A
Department of Medicine, University of Texas Southwestern Medical Center, Dallas 75235-9047, USA.
J Am Soc Echocardiogr. 1998 Mar;11(3):228-35. doi: 10.1016/s0894-7317(98)70084-7.
Although myocardial contrast echocardiography accurately demarcates area at risk during total coronary occlusion, the ability of MCE to delineate area at risk in the presence of residual antegrade flow is unknown. We hypothesized that perfusion defects in myocardial segments supplied by severe coronary stenoses with residual antegrade flow could be detected by MCE using intravenous FS069. We studied 13 open-chest dogs using an intravenous injection of FS069 during intermittent harmonic imaging. Images were collected at baseline, during acute ischemia with residual antegrade flow, physiologic hyperemia (release of stenosis), and total coronary occlusion. Regional myocardial blood flow was assessed using colored microspheres. MCE risk area during acute ischemia with residual antegrade flow and total occlusion was planimetered and compared with pathologic risk area (area unstained by monastral blue). Background-subtracted peak videointensity in the risk area was assessed for all flow states. Regional myocardial blood flow confirmed expected flow states, being significantly greater during physiologic hyperemia (4.16 +/- 1.22 ml/min/g) than at baseline (0.71 +/- 0.19 ml/min/g) and significantly diminished during coronary stenosis with residual antegrade flow (0.20 +/- 0.16 ml/min/g) and total occlusion (0.09 +/- 0.06 ml/min/g; p < 0.0001). Myocardial risk area by MCE during coronary stenosis with residual antegrade flow correlated well with pathologic risk area determined by monastral blue staining (r = 0.86). Peak videointensity during coronary stenosis (111 +/- 27) was significantly less than at baseline (157 +/- 50) but greater than during total occlusion (81 +/- 34; p < 0.0001). In conclusion, intravenous FS069 in conjunction with intermittent harmonic imaging delineates area at risk in ischemic myocardium supplied by a coronary stenoses with residual antegrade flow. The presence of a perfusion defect on MCE does not necessarily imply that the coronary artery is totally occluded.
尽管心肌对比超声心动图能够准确界定完全冠状动脉闭塞时的危险区域，但在存在残余正向血流的情况下，心肌对比超声心动图界定危险区域的能力尚不清楚。我们推测，使用静脉注射FS069的心肌对比超声心动图能够检测出由严重冠状动脉狭窄且伴有残余正向血流所供应的心肌节段中的灌注缺损。我们对13只开胸犬进行了研究，在间歇谐波成像期间静脉注射FS069。在基线、存在残余正向血流的急性缺血、生理性充血（解除狭窄）以及完全冠状动脉闭塞期间采集图像。使用彩色微球评估局部心肌血流。对存在残余正向血流的急性缺血和完全闭塞期间的心肌对比超声心动图危险区域进行面积测量，并与病理危险区域（未被莫纳斯特蓝染色的区域）进行比较。对所有血流状态下危险区域的背景扣除后的峰值视频强度进行评估。局部心肌血流证实了预期的血流状态，生理性充血期间（4.16±1.22毫升/分钟/克）明显高于基线（0.71±0.19毫升/分钟/克），在伴有残余正向血流的冠状动脉狭窄期间（0.20±0.16毫升/分钟/克）和完全闭塞期间（0.09±0.06毫升/分钟/克；p<0.0001）明显减少。在伴有残余正向血流的冠状动脉狭窄期间，心肌对比超声心动图显示的心肌危险区域与莫纳斯特蓝染色确定的病理危险区域相关性良好（r=0.86）。冠状动脉狭窄期间的峰值视频强度（111±27）明显低于基线（157±50），但高于完全闭塞期间（81±34；p<0.0001）。总之，静脉注射FS069结合间歇谐波成像能够界定由伴有残余正向血流的冠状动脉狭窄所供应的缺血心肌中的危险区域。心肌对比超声心动图上存在灌注缺损并不一定意味着冠状动脉完全闭塞。
