Chaitman B R, Fisher L D, Bourassa M G, Davis K, Rogers W J, Maynard C, Tyras D H, Berger R L, Judkins M P, Ringqvist I, Mock M B, Killip T
Am J Cardiol. 1981 Oct;48(4):765-77. doi: 10.1016/0002-9149(81)90156-9.
The 3 year cumulative survival rate of 1,492 patients with left main coronary artery disease (50 percent or greater stenosis of luminal diameter) enrolled in the Collaborative Study in Coronary Artery Surgery (CASS) was 91 percent for the surgical group and 69 percent for patients treated medically (p less than 0.0001). Mortality was significantly greater in patients with impaired left ventricular function. The difference between medical and surgical therapy was significant for patients who had normal, moderately abnormal and severely impaired left ventricular function and for patients with stenosis of the left main coronary artery of 50 to 59, 60 to 69, 70 to 79 and 80 percent or greater. Aortocoronary bypass surgery did not significantly improve survival in patient subgroups who had (1) a nonstenotic dominant right or balanced coronary circulation, (2) a stenotic dominant right coronary artery and normal left ventricular function, and (3) left main coronary stenosis of 50 to 59 percent and normal or mildly abnormal left ventricular function. The Cox proportional hazards model was used to select baseline variables that were independent predictors of long-time mortality. The model selected left ventricular score, age, congestive heart failure score, hypertension, percent left main coronary arterial stenosis and coronary arterial dominance as the baseline variables most predictive of long-term survival. A clinical and angiographic prognostic risk index developed from these six baseline variables showed significantly improved survival for the surgical cohort in each of four risk categories. In the best and worst risk category, the 3 year survival rate was 97 and 82 percent, respectively, for the surgical group and 85 and 34 percent, respectively, for the medical group (p less than or equal to 0.0002). The data from this observational study show that coronary bypass surgery prolongs life in most patients with left main coronary artery disease, particularly those who have severe narrowing of the left main coronary artery or impaired left ventricular function. The results permit a better understanding of the natural history of left main coronary artery disease and permit a more accurate estimate of long-term survival for individual patients through the use of a clinical-angiographic risk index.
在冠状动脉外科合作研究（CASS）中登记的1492例左主冠状动脉疾病（管腔直径狭窄50%或以上）患者，手术组的3年累积生存率为91%，药物治疗组为69%（p<0.0001）。左心室功能受损患者的死亡率显著更高。对于左心室功能正常、中度异常和严重受损的患者，以及左主冠状动脉狭窄50%至59%、60%至69%、70%至79%和80%或更高的患者，药物治疗和手术治疗之间的差异显著。主动脉冠状动脉搭桥手术在以下患者亚组中并未显著提高生存率：（1）无狭窄的优势右冠状动脉或均衡冠状动脉循环；（2）狭窄的优势右冠状动脉且左心室功能正常；（3）左主冠状动脉狭窄50%至59%且左心室功能正常或轻度异常。采用Cox比例风险模型选择作为长期死亡率独立预测因素的基线变量。该模型选择左心室评分、年龄、充血性心力衰竭评分、高血压、左主冠状动脉狭窄百分比和冠状动脉优势作为最能预测长期生存的基线变量。根据这六个基线变量制定的临床和血管造影预后风险指数显示，手术队列在四个风险类别中的生存率均显著提高。在最佳和最差风险类别中，手术组的3年生存率分别为97%和82%，药物治疗组分别为85%和34%（p≤0.0002）。这项观察性研究的数据表明，冠状动脉搭桥手术可延长大多数左主冠状动脉疾病患者的生命，尤其是那些左主冠状动脉严重狭窄或左心室功能受损的患者。这些结果有助于更好地了解左主冠状动脉疾病的自然病史，并通过使用临床血管造影风险指数更准确地估计个体患者的长期生存率。
