Di Carli M F, Asgarzadie F, Schelbert H R, Brunken R C, Laks H, Phelps M E, Maddahi J
Department of Medical and Molecular Pharmacology, University of California at Los Angeles, School of Medicine, USA.
Circulation. 1995 Dec 15;92(12):3436-44. doi: 10.1161/01.cir.92.12.3436.
Studies of patients with coronary artery disease and left ventricular dysfunction have shown that preoperative quantification of myocardial viability may be clinically useful to identify those patients who will benefit most from revascularization both functionally and prognostically. However, the relation between preoperative extent of viability and change in heart failure symptoms has not been documented carefully. We assessed the relation between the magnitude of improvement in heart failure symptoms after coronary artery bypass surgery (CABG) and the extent of myocardial viability as assessed by use of quantitative analysis of preoperative positron emission tomography (PET) images.
We studied 36 patients with ischemic cardiomyopathy (mean left ventricular ejection fraction, 28 +/- 6%) undergoing CABG. Preoperative extent and severity of perfusion abnormalities and myocardial viability (flow-metabolism mismatch) were assessed by use of quantitative analysis of PET images with 13N ammonia and fluorine-18-deoxyglucose. Each patient's functional status was determined before and after CABG by use of a Specific Activity Scale. Mean perfusion defect size and severity were 63 +/- 13% and 33 +/- 12%, respectively. Total extent of a PET mismatch correlated linearly and significantly with percent improvement in functional status after CABG (r = .87, P < .0001). A blood flow-metabolism mismatch > or = 18% was associated with a sensitivity of 76% and a specificity of 78% for predicting a change in functional status after revascularization. Patients with large mismatches (> or = 18%) achieved a significantly higher functional status compared with those with minimal or no PET mismatch (< 5%) (5.7 +/- 0.8 versus 4.9 +/- 0.7 metabolic equivalents, P = .009). This resulted in an improvement of 107% in patients with large mismatches compared with only 34% in patients with minimal or no PET mismatch.
In patients with ischemic cardiomyopathy, the magnitude of improvement in heart failure symptoms after CABG is related to the preoperative extent and magnitude of myocardial viability as assessed by use of PET imaging. Patients with large perfusion-metabolism mismatches exhibit the greatest clinical benefit after CABG.
对冠状动脉疾病和左心室功能不全患者的研究表明，术前对心肌存活性进行量化在临床上可能有助于识别那些在功能和预后方面能从血运重建中获益最大的患者。然而，术前存活性范围与心力衰竭症状变化之间的关系尚未得到仔细记录。我们评估了冠状动脉搭桥手术（CABG）后心力衰竭症状改善程度与通过术前正电子发射断层扫描（PET）图像定量分析评估的心肌存活性范围之间的关系。
我们研究了36例接受CABG的缺血性心肌病患者（平均左心室射血分数为28±6%）。通过使用13N氨和氟-18-脱氧葡萄糖对PET图像进行定量分析，评估术前灌注异常的范围和严重程度以及心肌存活性（血流-代谢不匹配）。使用特定活动量表在CABG前后确定每位患者的功能状态。平均灌注缺损大小和严重程度分别为63±13%和33±12%。PET不匹配的总范围与CABG后功能状态改善百分比呈线性且显著相关（r = 0.87，P < 0.0001）。血流-代谢不匹配≥18%对于预测血运重建后功能状态变化的敏感性为76%，特异性为78%。与PET不匹配最小或无PET不匹配（<5%）的患者相比，不匹配大（≥18%）的患者功能状态显著更高（5.7±0.8与4.9±0.7代谢当量，P = 0.009）。与PET不匹配最小或无PET不匹配的患者相比，不匹配大的患者改善了107%，而PET不匹配最小或无PET不匹配的患者仅改善了34%。
在缺血性心肌病患者中，CABG后心力衰竭症状改善程度与通过PET成像评估的术前心肌存活性范围和程度相关。灌注-代谢不匹配大的患者在CABG后表现出最大的临床获益。
