摘要
目的:探讨碎裂QRS波(fragmented QRS complexes, f-QRS)对非缺血性心肌病患者心室同步性评价的意义。
方法:选取苏州大学附属第一医院心血管内科及外科的住院及门诊病人,共64人,其中男性37人,女性27人,年龄53.2±14.4岁,所入选患者满足以下条件:左室射血分数≤45%、窦性心律、QRS波时限<120ms;为排除缺血性心肌病对心室同步性的影响,所有患者既往均进行冠状动脉造影检查,另若存在以下情况之一均为排除标准:器质性的心脏瓣膜病,心肌梗死病史,有关心肌缺血的心电图阳性发现,冠脉造影发现的显著冠脉狭窄(任何冠脉狭窄>50%),持续性心房颤动、频发的室性、房性或交界性期前收缩等显著的心律不齐,永久起搏器植入病史。根据体表心电图分为两组:A组:f-QRS波组,共22人,其中男性13人,女性9人,年龄55.1±14.3岁;B组:无f-QRS波组,共42人,其中男性24人,女性18人,年龄52.0±14.1岁。两组人群均行超声心动图组织速度成像检查,以Ts-TD≥32.6ms作为存在室内不同步标准,比较两组人群室内同步性有无差异及差异有无显著性,并观察室内不同步节段与体表f-QRS波导联的对应关系。
结果:经超声心动图组织速度成像检查示A组存在室内不同步共17例,占A组76%(17/22),室内同步者5例,占24%(5/22);B组存在室内不同步患者共6例,占B组14%(6/42),室内同步者36例,占86%(36/42);两组间差别有显著统计学意义(P<0.0001);f-QRS波对非缺血性心肌病患者存在左室内不同步性的检测的特异度、灵敏度、阳性预测值、阴性预测值分别为88%,74%,77%,86%。在A组存在室内不同步的17例患者中,经组织速度成像检查有13名患者f-QRS波出现导联所提示的心脏节段为左室收缩最为延迟阶段或收缩不同步节段之一,占A组室内不同步患者的76%。
结论:1. f-QRS在非缺血性心肌病中并非少见,且常出现于下壁导联。
2. f-QRS波是非缺血性心肌病患者左室内同步不良的一个简便指标,对左室内同步不良预测具有较高的敏感性、特异性。
3.存在f-QRS波的非缺血性心肌病心衰患者,f-QRS波所代表的室内节段常为心室内收缩最为延迟节段或收缩不同步节段之一。
Objective: To investigate the relationship between fragmented QRS complexes andintraventricular dyssynchrony in patients with nonischemic cardiomyopathy in sinusrhythm.
Methods: The present study was conducted in the Inpatient and OutpatientDepartment of Cardiology in First Affiliated Hospital of Suzhou University. sixty-fourpatients were consecutively recruited,thirty-seven males, twenty-seven females, with amean age of53.2±14.4years. All patients meet the following requirements: Leftventricular ejection fraction of less than45%and sinus rhythm having narrow (less than120ms) QRS complexes. Coronary angiography was performed for all patients in orderto exclued ischemic etiology of dilated cardiomyopathy. patients with organic valvularheart disease, history of myocardial infarction, ischemic electrocardiogramfinding,angiographically significant coronary artery disease (>50stenosis in anyepicardial coronary artery), persistent atrial fibrillation, frequent ventricular、atrial orjunctional premature contraction and other arrhythmia, permanent pacemakers wereexcluded from the study. Patients were categorized into2subgroups according to theirbasal ECGs: Group A was the fragmented QRS group, twenty-two person, thirteen malesand nine females with mean age55.1±14.3years; Group B was nonfragmented QRSgroup, forty-two patients, twenty-four males and eighteen females with mean age52.0±14.1years, who did not have fragmented QRS complexs in their restingelectrocardiogram. All patients was evaluated carefully for their left ventricularsynchronization by Tissue Doppler Inaging, Significant systolic dyssynchrony wasdefined as a Ts-TD>32.6ms accroding to Yu et al study previously. We observed thedifferent of intraventricular synchrony of two groups and investigated the association off-QRS and maximal dyssynchronic segment or one of the dyssynchronic segment.
Results: There were seventeen patients (76%) with f-QRS complexes had significant LV dyssynchrony in Group A, five patients (24%) did not have LVdyssynchrony,only six patients (14%) in Group B had significant LV dyssynchrony,thrity-six patients (86%) did not have LV dyssynchrony guided by Tissue DopplerInaging.there was statistically significant diffierence between the two groups (P<0.0001).The presence of f-QRS complexes in the basal ECG in patients with nonischemiccardiomyopathy was found to detect intraventricular dyssynchrony with74%sensitivity,88%specificity, a positive predictive value of77%and a negative predictive value of86%. Among seventeen patients with significant intraventricular dyssynchrony onechocardiography in Group A,thirteen patients (76%,13/17) had ECG fragmentation inthe maximal dyssynchronic segment or one of the dyssynchronic segment.
Conclusion:1. Fragmented QRS complexes is very common in nonischemiccardiomyopathy, often appears in inferior leads.2. Fragmented QRS complexes in basalECG is a simple and convenient index to predict intraventricular dyssynchrony innonischemic cardiomyopathy patients with a narrow QRS interval and sinus rhythm. Ithas high sensitivity and specificity.3. The leads of fragmented QRS complexes in basalECG often indicate the maximal dyssynchronic segment or one of the dyssynchronicsegment.
引文
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