White James A, Yee Raymond, Yuan Xiaping, Krahn Andrew, Skanes Allan, Parker Michele, Klein George, Drangova Maria
Division of Cardiology, Department of Medicine, University of Western Ontario, London, Ontario, Canada.
J Am Coll Cardiol. 2006 Nov 21;48(10):1953-60. doi: 10.1016/j.jacc.2006.07.046. Epub 2006 Oct 31.
We evaluated the ability of delayed enhancement magnetic resonance imaging (DE-MRI) to predict clinical response to cardiac resynchronization therapy (CRT).
Cardiac resynchronization therapy reduces morbidity and mortality in selected heart failure patients. However, up to 30% of patients do not have a response. We hypothesized that scar burden on DE-MRI predicts response to CRT.
The DE-MRI was performed on 28 heart failure patients undergoing CRT. Patients with QRS > or =120 ms, left ventricular ejection fraction < or =35%, New York Heart Association functional class II to IV, and dyssynchrony > or =60 ms were studied. Baseline and 3-month clinical follow-up, wall motion, 6-min walk, and quality of life assessment were performed. The DE-MRI was performed 10 min after 0.20 mmol/kg intravenous gadolinium. Scar measured by planimetry was correlated with response criteria.
Twenty-three patients completed the protocol (mean age 64.9 +/- 11.7 years), with 12 (52%) having a history of myocardial infarction. Thirteen (57%) patients met response criteria. Percent total scar was significantly higher in the nonresponse versus response group (median and interquartile range of 24.7% [18.1 to 48.7] vs. 1.0% [0.0 to 8.7], p = 0.0022) and predicted nonresponse by receiver-operating characteristic analysis (area = 0.94). At a cutoff value of 15%, percent total scar provided a sensitivity and specificity of 85% and 90%, respectively, for clinical response to CRT. Similarly, septal scar < or =40% provided a 100% sensitivity and specificity for response. Regression analysis showed linear correlations between percent total scar and change in each of the individual response criteria.
The DE-MRI accurately predicted clinical response to CRT. This technique offers unique information in the assessment of patients referred for CRT.
我们评估了延迟强化磁共振成像（DE-MRI）预测心脏再同步治疗（CRT）临床反应的能力。
心脏再同步治疗可降低特定心力衰竭患者的发病率和死亡率。然而，高达30%的患者无反应。我们假设DE-MRI上的瘢痕负荷可预测CRT的反应。
对28例接受CRT的心力衰竭患者进行DE-MRI检查。研究对象为QRS≥120毫秒、左心室射血分数≤35%、纽约心脏协会心功能分级为II至IV级且不同步≥60毫秒的患者。进行了基线和3个月的临床随访、室壁运动、6分钟步行及生活质量评估。静脉注射0.20 mmol/kg钆喷酸葡胺10分钟后进行DE-MRI检查。通过面积测量法测得的瘢痕与反应标准相关。
23例患者完成了方案（平均年龄64.9±11.7岁），其中12例（52%）有心肌梗死病史。13例（57%）患者达到反应标准。无反应组的总瘢痕百分比显著高于反应组（中位数及四分位数间距分别为24.7%[18.1至48.7]对1.0%[0.0至8.7]，p = 0.0022），且通过受试者操作特征分析预测无反应（曲线下面积 = 0.94）。总瘢痕百分比为15%时，对CRT临床反应的敏感性和特异性分别为85%和90%。同样，间隔瘢痕≤40%时，对反应的敏感性和特异性均为100%。回归分析显示总瘢痕百分比与各个反应标准的变化之间呈线性相关。
DE-MRI准确预测了CRT的临床反应。该技术在评估接受CRT的患者时提供了独特信息。
