Birnbaum Y, Luo H, Atar S, Fishbein M C, Brasch A V, Nagai T, Pal D, Nishioka T, Chae J S, Zanelli C, Peterson T M, Siegel R J
Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA.
J Thromb Thrombolysis. 2001 May;11(3):229-34. doi: 10.1023/a:1011964904848.
Recently it has been demonstrated that transcutaneous delivery of ultrasound combined with tissue plasminogen activator (tPA) is more effective than tPA alone in recanalizing acutely thrombosed canine coronary arteries. In the present study, we investigated the incidence of partial (> or =50%) and complete (> or =70%) ST-segment elevation resolution in the precordial leads of dogs with experimental acute myocardial infarction that were treated with tissue plasminogen activator (tPA) alone or in combination with noninvasive transcutaneous delivery of high-intensity low frequency (27[emsp3 ]kHz) ultrasound.
Thrombotic coronary occlusions were induced in the midportion of left anterior descending (LAD) coronary artery by electrical injury in 24 dogs. All dogs were given intravenous heparin and tPA. Dogs were randomized to tPA alone (n=12) or combined tPA and adjunctive transcutaneous ultrasound (US) delivery (n=12). Electrocardiograms were recorded at 1) baseline, 2) after coronary occlusion just before initiation of therapy, 3) when coronary angiography showed recanalization of the coronary artery (or at 90 minutes after initiation of therapy if reperfusion did not occur before then) and 4) 90 minutes later. ST amplitude was measured in all 6 precordial leads.
ST-segment amplitude at baseline was comparable between the tPA and the US group. Before initiation of therapy, sum of ST-segment elevation tended to be higher in the US group. At reperfusion and 90 minutes thereafter, sum of ST-segment amplitude tended to be smaller for the US group than in the tPA group (p<0.001 for the time effect; p=0.118 for the time x group interaction). Up to 90 minutes after initiation of therapy >/=50% resolution of the sum of precordial ST elevation was detected in 7 out of 11 dogs (63.6%) in the tPA group versus 10 out of 11 dogs (90.9%) in the US group. Ninety minutes thereafter, 3 out of 7 dogs in the tPA group (42.9%) versus 9 of 11 dogs in the US group (81.8%) had >/=50% resolution of the sum of precordial ST elevation.
The combination of tPA with noninvasive transcutaneous delivery of low frequency high-intensity ultrasound resulted in greater resolution of ST-segment elevation when reperfusion occurs and 90 minutes thereafter, as well as a higher rate of epicardial coronary artery reperfusion.
最近有研究表明，经皮超声联合组织型纤溶酶原激活剂（tPA）在使急性血栓形成的犬冠状动脉再通方面比单独使用tPA更有效。在本研究中，我们调查了单独使用组织型纤溶酶原激活剂（tPA）或联合无创经皮高强度低频（27kHz）超声治疗的实验性急性心肌梗死犬胸前导联部分（≥50%）和完全（≥70%）ST段抬高消退的发生率。
通过电损伤在24只犬的左前降支（LAD）冠状动脉中段诱导血栓性冠状动脉闭塞。所有犬均静脉给予肝素和tPA。犬被随机分为单独使用tPA组（n = 12）或联合tPA及辅助经皮超声（US）治疗组（n = 12）。在以下时间点记录心电图：1）基线时；2）冠状动脉闭塞后、治疗开始前；3）冠状动脉造影显示冠状动脉再通时（如果在此之前未发生再灌注，则在治疗开始后90分钟）；4）90分钟后。测量所有6个胸前导联的ST段幅度。
tPA组和US组基线时的ST段幅度相当。治疗开始前，US组的ST段抬高总和往往更高。在再灌注时及之后90分钟，US组的ST段幅度总和往往比tPA组小（时间效应p<0.001；时间×组交互作用p = 0.118）。治疗开始后90分钟内，tPA组11只犬中有7只（63.6%）胸前导联ST段抬高总和消退≥50%，而US组11只犬中有10只（90.9%）。90分钟后，tPA组7只犬中有3只（42.9%）胸前导联ST段抬高总和消退≥50%，而US组11只犬中有9只（81.8%）。
tPA与无创经皮低频高强度超声联合使用，在再灌注时及之后90分钟，ST段抬高的消退更明显，心外膜冠状动脉再灌注率也更高。
