Oeff M, Gödde P, Agrawal R, Endt P, Trahms L, Schultheiss H P
Medizinische Klinik II Kardiologie und Pulmologie, Universitätsklinikum Bejamin Franklin, Freie Universität Berlin, Hindenburgdamm 30, 12200, Berlin.
Herzschrittmacherther Elektrophysiol. 1997 Sep;8(3):195-204. doi: 10.1007/BF03042402.
Fragmented and delayed activation of ventricular myocardium can cause malignant tachyarrhythmias. By detection of ventricular late potentials only a severely delayed depolarisation is registered, but not the intra QRS-activation. The aim of this study was to examine the complete phase of ventricular depolarisation, to detect and to quantify abnormal electrical activation by magnetocardiography and to estimate in a small group of patients with coronary heart disease the prognostic significance.In 26 healthy subjects, 32 patients after myocardial infarction without malignant ventricular arrhythmias and 10 patients with coronary heart disease and a history of sustained, monomorph ventricular tachycardia magnetocardiography was performed in a magnetically shielded room. To quantify the fragmentation of QRS a fragmentation-index (FI) was calculated. Besides signal averaged ECG, in patients with coronary heart disease cardiac catheterisation and in patients with arrhythmias electrophysiological testing was performed. The FI for the three groups was significantly different (p<0,005). The mean FI in the group of healthy subjects was 20,4+/-5,4, in the group of postinfarction-patients without arrhythmias 27+/-12,1 and in the group of patients with coronary heart disease and ventricular arrhythmias 49,5+/-17,9. Dichotomized at 36 the sensitivity was 80%, the specifity 93%, the positive predictive value was 66% and the negative predictive value 96%. The FI was correlated to the extent of regional wall-motion-irregularity and global ejection fraction.Analyzing late potentials, the values for sensitivity and positive predictive value were surprisingly low (20% and 50%, respectively). The specifity was 96%, the negative predictive value was 88%. Calculating the FI on the basis of electrical signals only an insufficient discrimination of the groups was possible.In the follow-up period of two years one post-infarctional patient was resusciated because of ventricular fibrillation. The FI of this patient was 17.One patient with coronary 3-vessel-disease and left ventricular ejection fraction of 50% died due to acute myocardial infarction, his FI was 39.
By means of magnetocardiography fragmented ventricular activation in patients with coronary heart disease was demonstrated even within the QRS-complex and could be correlated to ventricular tachyarrhythmias.
心室心肌的碎裂和延迟激活可导致恶性快速性心律失常。通过检测心室晚电位，仅记录到严重延迟的去极化，但未记录到QRS波群内的激活情况。本研究的目的是检查心室去极化的完整阶段，通过磁心动图检测并量化异常电激活，并在一小群冠心病患者中评估其预后意义。对26名健康受试者、32名无恶性室性心律失常的心肌梗死后患者以及10名有持续性单形性室性心动过速病史的冠心病患者，在磁屏蔽室内进行了磁心动图检查。为了量化QRS波群的碎裂程度，计算了碎裂指数（FI）。除了信号平均心电图外，对冠心病患者进行了心导管检查，对心律失常患者进行了电生理检查。三组的FI有显著差异（p<0.005）。健康受试者组的平均FI为20.4±5.4，无心律失常的心肌梗死后患者组为27±12.1，有冠心病和室性心律失常的患者组为49.5±17.9。以36为界进行二分法分析，敏感性为80%，特异性为93%，阳性预测值为66%，阴性预测值为96%。FI与局部室壁运动不规则程度和整体射血分数相关。分析晚电位时，敏感性和阳性预测值出人意料地低（分别为20%和50%）。特异性为96%，阴性预测值为88%。仅根据电信号计算FI，对各组的区分能力不足。在两年的随访期内，一名心肌梗死后患者因心室颤动复苏。该患者的FI为17。一名患有三支血管病变且左心室射血分数为50%的冠心病患者因急性心肌梗死死亡，其FI为39。
通过磁心动图证明，冠心病患者即使在QRS波群内也存在心室激活碎裂，且与室性快速性心律失常相关。
