Prewitt R M, Gu S, Schick U, Ducas J
Department of Medicine, University of Manitoba, Winnipeg, Canada.
Chest. 1995 Apr;107(4):1146-51. doi: 10.1378/chest.107.4.1146.
Although many studies have confirmed the efficacy of thrombolytic therapy in treatment of acute myocardial infarction, few studies have been designed to determine which dose regimen optimizes the rate of coronary thrombolysis. This study was designed to compare the efficacy of coronary thrombolysis obtained with intravenous administration of three dose regimens of recombinant tissue plasminogen activator (rtPA). The same total dose was administered as a bolus, over 30 min, or over 90 min. A canine model was employed. Coronary thrombosis was induced by injection of radioactive blood clot through a catheter placed in the left anterior descending coronary artery. Subsequently, 18 dogs were randomized into 3 groups of 6 dogs each. In group 1 dogs, 0.5 mg/kg of rtPA was administered intravenously as a bolus; in the group 2 dogs, rtPA was administered intravenously over 30 min (rtPA30); in the group 3 dogs, the drug was administered over 90 min (rtPA90). Coronary thrombolysis was assessed with a gamma camera. While at 100 min, the extent of clot lysis was similar between groups, 15 and 30 min after the start of rtPA administration, coronary thrombolysis was significantly less in the rtPA90 group. These results indicate that for a given total dose of rtPA, the rate of intravenous administration may significantly affect the rate of coronary thrombolysis.
尽管许多研究已证实溶栓疗法在治疗急性心肌梗死方面的疗效，但很少有研究旨在确定哪种剂量方案能使冠状动脉溶栓率达到最佳。本研究旨在比较静脉注射三种剂量方案的重组组织型纤溶酶原激活剂（rtPA）后获得的冠状动脉溶栓疗效。相同的总剂量分别作为静脉推注、在30分钟内或在90分钟内给药。采用犬模型。通过将放射性血凝块注入置于左前降支冠状动脉的导管来诱导冠状动脉血栓形成。随后，18只狗被随机分为3组，每组6只。在第1组狗中，以静脉推注的方式给予0.5mg/kg的rtPA；在第2组狗中，rtPA在30分钟内静脉给药（rtPA30）；在第3组狗中，药物在90分钟内给药（rtPA90）。用γ相机评估冠状动脉溶栓情况。虽然在100分钟时，各组之间的血凝块溶解程度相似，但在rtPA给药开始后15分钟和30分钟时，rtPA90组的冠状动脉溶栓明显较少。这些结果表明，对于给定的rtPA总剂量，静脉给药速度可能会显著影响冠状动脉溶栓速度。
