心磁图对静态心电图正常的冠心病患者的诊断价值

Diagnostic value of magnetocardiography in coronary heart disease patients with normal resting electrocardiogram

目的 探讨心磁图 (MCG)法对静息心电图正常的冠心病患者的诊断价值。方法 采用安装于非屏蔽室内的德国SQUID公司的 7通道MCG仪检测 6 4例静息心电图正常的冠心病患者 (冠状动脉造影至少有1支血管狭窄≥ 70 %) (CHD组 )和 5 8名健康体检者 (对照组 )的心脏MCG和电流密度分布图 ,分析两个定量指标 :①α平均角 :计算ST T间期内J点至T波顶点的第 2个 1/ 4段所包含的心电向量图的平均角α ;②R值 :异常MCG所占的百分率。结果 CHD组的α平均角为 2 36 .91°± 76 .46° ,显著高于对照组的 2 8.73°± 2 6 .43°(P <0 .0 1) ;CHD组的R值为 (5 3.40± 2 8.5 8) %,显著高于对照组的 (2 8.2 3± 2 4.2 0 ) %(P <0 .0 1)。结论 具有精细数据分析的静息MCG对静态心电图正常的冠心病患者的诊断价值优于心电图。MCG可以检测心肌缺血损伤电流造成的ST段基线位移 ,有利于早期诊断冠心病。

Objective To appraise the diagnostic value of magnetocardiography (MCG) in coronary heart disease (CHD) patients with normal resting electrocardiogram (ECG).Methods MCG measurements were performed in sixty-four coronary heart patients with normal resting ECG and fifty-eight healthy volunteers by seven-channel magnetocardiograph (MCG7,SQUID AG,Germany) installed in an unshielded room. CHD was diagnosed in case of one-vessel stenosis≥70% . Two quantitative indicators were analyzed: α average angle: average direction of maximal vectors during the interval of the ST-segment which included the second quarter from the J-point to the apex of T wave according to the vectocardiogram and R value: percentage of abnormal magnetocardiogram.Results α average angle of CHD group was 236.91° ±76.46°, much greater than that of the healthy group ( 28.73° ±26.43°,P <0.01).R value of CHD group( 53.40% ±28.58%)was much higher than that of the healthy group ( 28.23% ±24.20%,P< 0.01). Conclusion The resting MCG with precise data analysis is superior to conventional resting ECG for diagnosis in patients with CHD. MCG can detect displacement of ST-segment caused by electric current due to ischemic myocardial injury and is helpful in early diagnosis of coronary heart disease.