扩张型心肌病患者微伏级T波电交替检测分析

Detection and analysis of microvolt T-wave alternans in patients with dilated cardiomyopathy

目的研究扩张型心肌病患者微伏级T波电交替(MTWA)的发生情况及与心率的关系。方法对31例扩张型心肌病患者用频谱法检测MTWA,分析扩张型心肌病MTWA的阳性率及不确定结果的原因,静息和运动时MTWA的发生情况,心率与交替压(Valt)的关系。结果①扩张型心肌病患者MTWA的阳性率为35.48%;②扩张型心肌病者,运动时的心率大于静息时,运动时各导联的Valt值大于静息时(P均<0.01)。静息时MTWA阳性2例,运动时MTWA阳性11例,运动时MTWA的阳性率高于静息时(35.48%vs 6.45%,P<0.01);③心率与综合导联Valt呈正相关,随心率的增加,Valt增大(r=0.984,P<0.01)。结论①扩张型心肌病患者MTWA阳性率高于正常人;②MTWA的发生与心率相关,随心率增快,Valt增大,MTWA阳性检出率增加。

Objective To investigate the prevalence of Microvoh T-wave ahernans （MTWA） in patients with dilated cardiomyopathy. Methods MTWA was assessed in 31 dilated cardiomyopathy patients with spectral method. The MTWA positive rate of patients with dilated cardiomyopathy and the cause of indeterminate MTWA were analyzed. The prevalence of MTWA in patients with dilated cardiomyopathy at rest and exercise and the correlation between the heart rate and ahernans voltage（ Valt ） were analyzed. Results The MTWA positive rate of patients with dilated cardiomyopathy was 35.48%. The mean heart rate for patients with cardiomyopathy during exercise was higher than that at rest. The Valt during exercise was larger than that at rest（ all P 〈 0.01 ）. The MTWA positive rate during exercise was higher than that at rest （ 35.48% vs 6.45% ,P 〈 0.01 ）. There was significant correlation between the heart rate and Val, in vector magnitude（ r = 0. 984, P 〈0.0I ）, and Valt, increased with the increase of heart rate. Conclusion The MTWA positive rate of patients with dilated cardiomyopathy is higher than that in healthy subjects. The prevalence of MTWA is positively correlated with heart rate.