Cerqueira M D, Maynard C, Ritchie J L, Davis K B, Kennedy J W
Department of Medicine, University of Washington School of Medicine, Seattle.
J Am Coll Cardiol. 1992 Dec;20(7):1452-9. doi: 10.1016/0735-1097(92)90436-q.
The aim of this study was to determine whether streptokinase treatment improves long-term survival in patients with acute myocardial infarction.
Thrombolytic treatment for acute myocardial infarction reduces early mortality and improves the 1-year survival rate, but the long-term (3 to 8 years) survival benefits of treatment and the relation between survival and baseline clinical characteristics, infarct size and ventricular function have not been established.
We assessed survival status at a minimum of 3 and a mean of 4.9 +/- 2.3 years in 618 patients randomized between 1981 and 1986 to receive conventional treatment (n = 293) or thrombolysis with streptokinase (n = 325) in the Western Washington Intracoronary (n = 250) and Intravenous (n = 368) Streptokinase in Myocardial Infarction trials. The relation between long-term survival and thrombolytic treatment, admission baseline clinical characteristics and late radionuclide tomographic thallium-201 infarct size and ejection fraction was assessed in a subset of patients.
Survival at 6 weeks was 94% in patients who received streptokinase versus 88% in the control group (p = 0.01). However, survival at 3 years was 84% in the streptokinase group and 82% in the control group and for the total period of follow-up, there was no significant survival benefit (p = 0.16). Analysis by infarct location showed a higher survival rate at 3 years for patients treated with anterior infarction (76% vs. 67% for the control group), but no overall survival benefit (p = 0.14). Survival at 3 years for patients with an inferior infarction was 89% in the streptokinase group and 91% in the control group (p = 0.62). By stepwise Cox regression analysis, admission clinical variables associated with decreased long-term survival were anterior infarction, advanced age, history of prior infarction and the presence of pulmonary edema or hypotension. Although streptokinase therapy was associated with improved survival, it was not an independent determinant of survival (p = 0.069). Ejection fraction and thallium-201 infarct size measured approximately 8 weeks after enrollment had a strong association with long-term survival. Univariate analysis in a subgroup of 289 patients with complete data selected infarct size, ejection fraction, age and history of prior infarction as predictors of survival. In the multivariate model, only ejection fraction (p < 0.0001), age (p = 0.008) and prior myocardial infarction (p = 0.02) remained strong predictors.
In these early trials of thrombolytic therapy for acute myocardial infarction, streptokinase improved early survival, but there was little long-term survival benefit. This failure to show an improvement in the 3- to 8-year survival rate may also reflect the need to study a larger group of patients or to initiate treatment earlier after symptom onset.
本研究旨在确定链激酶治疗是否能提高急性心肌梗死患者的长期生存率。
急性心肌梗死的溶栓治疗可降低早期死亡率并提高1年生存率，但治疗的长期（3至8年）生存获益以及生存与基线临床特征、梗死面积和心室功能之间的关系尚未明确。
我们评估了1981年至1986年间随机接受传统治疗（n = 293）或链激酶溶栓治疗（n = 325）的618例患者的生存状况，这些患者来自西华盛顿冠状动脉内（n = 250）和静脉内（n = 368）链激酶治疗心肌梗死试验。在一部分患者中评估了长期生存与溶栓治疗、入院基线临床特征以及晚期放射性核素断层心肌灌注显像测定的铊-201梗死面积和射血分数之间的关系。
接受链激酶治疗的患者6周时生存率为94%，而对照组为88%（p = 0.01）。然而，链激酶组3年生存率为84%，对照组为82%，在整个随访期间，没有显著的生存获益（p = 0.16）。按梗死部位分析显示，前壁梗死患者3年生存率较高（76%对对照组的67%），但总体生存无获益（p = 0.14）。下壁梗死患者链激酶组3年生存率为89%，对照组为91%（p = 0.62）。通过逐步Cox回归分析，与长期生存降低相关的入院临床变量包括前壁梗死、高龄、既往梗死史以及肺水肿或低血压的存在。虽然链激酶治疗与生存改善相关，但它不是生存的独立决定因素（p = 0.069）。入组后约8周测量的射血分数和铊-201梗死面积与长期生存密切相关。在289例有完整数据的亚组患者中进行单因素分析，选择梗死面积、射血分数、年龄和既往梗死史作为生存预测因素。在多变量模型中，只有射血分数（p < 0.0001）、年龄（p = 0.008）和既往心肌梗死（p = 0.02）仍然是强有力的预测因素。
在这些急性心肌梗死溶栓治疗的早期试验中，链激酶改善了早期生存，但长期生存获益甚微。未能显示3至8年生存率的改善可能也反映了需要研究更大规模的患者群体或在症状发作后更早开始治疗。
