Bøtker H E, Lassen J F, Hermansen F, Wiggers H, Søgaard P, Kim W Y, Bøttcher M, Thuesen L, Pedersen A K
Department of Cardiology, Skejby Hospital, Aarhus, Denmark.
Circulation. 2001 Mar 27;103(12):1631-7. doi: 10.1161/01.cir.103.12.1631.
We evaluated the ability of electromechanical mapping of the left ventricle to distinguish between nonviable and viable myocardium in patients with ischemic cardiomyopathy.
Unipolar voltage amplitudes and local endocardial shortening were measured in 31 patients (mean+/-SD age, 62+/-8 years) with ischemic cardiomyopathy (ejection fraction, 30+/-9%). Dysfunctional regions, identified by 3D echocardiography, were characterized as nonviable when PET revealed matched reduction of perfusion and metabolism and as viable when perfusion was reduced or normal and metabolism was preserved. Mean unipolar voltage amplitudes and local shortening differed among normal, nonviable, and viable dysfunctional segments. Coefficient of variation for local shortening exceeded differences between groups and did not allow distinction between normal and dysfunctional myocardium. Optimum nominal discriminatory unipolar voltage amplitude between nonviable and viable dysfunctional myocardium was 6.5 mV, but we observed a great overlap between groups. Individual cutoff levels calculated as a percentage of electrical activity in normal segments were more accurate in the detection of viable dysfunctional myocardium than a general nominal cutoff level. The optimum normalized discriminatory value was 68%. Sensitivity and specificity were 78% for the normalized discriminatory value compared with 69% for the nominal value (P:<0.02).
Endocardial ECG amplitudes in patients with ischemic cardiomyopathy display a wide scatter, complicating the establishment of exact nominal values that allow distinction between viable and nonviable areas. Individual normalization of unipolar voltage amplitudes improves diagnostic accuracy. Electroanatomic mapping may enable identification of myocardial viability.
我们评估了左心室机电标测在区分缺血性心肌病患者非存活心肌和存活心肌方面的能力。
对31例（平均年龄±标准差，62±8岁）缺血性心肌病患者（射血分数，30±9%）测量单极电压幅度和局部心内膜缩短情况。经三维超声心动图确定的功能障碍区域，当PET显示灌注和代谢匹配性降低时被判定为非存活心肌，当灌注降低或正常且代谢保留时被判定为存活心肌。正常、非存活和存活功能障碍节段的平均单极电压幅度和局部缩短情况有所不同。局部缩短的变异系数超过了组间差异，无法区分正常心肌和功能障碍心肌。非存活和存活功能障碍心肌之间的最佳名义鉴别单极电压幅度为6.5 mV，但我们观察到组间存在很大重叠。以正常节段电活动百分比计算的个体截断水平在检测存活功能障碍心肌方面比一般名义截断水平更准确。最佳归一化鉴别值为68%。归一化鉴别值的敏感性和特异性为78%，而名义值为69%（P<0.02）。
缺血性心肌病患者的心内膜心电图幅度呈现广泛离散，使得建立能够区分存活和非存活区域的精确名义值变得复杂。单极电压幅度的个体归一化提高了诊断准确性。电解剖标测可能有助于识别心肌存活情况。
