肥厚型心肌病合并心房颤动患者射频消融术后心律失常复发心电指标的预测

目的:探讨心电指标f QRS与QTc联合是否能更好预测肥厚型心肌病(HCM)合并心房颤动患者导管消融术后的复发。方法:纳入在北京安贞医院行导管消融术的HCM合并心房颤动患者共120例(阵发/持续性心房颤动72/48)。消融策略包括:阵发性心房颤动患者行双侧肺静脉隔离(PVI);持续性心房颤动患者行PVI加左心房顶、二尖瓣峡部和三尖瓣峡部线性消融。术前评估基线心电图,f QRS定义为常规12导联心电图中至少两个连续导联的QRS波存在≥2个R波或者R波的波顶或S波的波谷出现顿挫波。采用Bazett公式校正QT间期。术后定期随访,复发定义为导管消融术后心电图或动态心电图记录的任何类型的>30 s的房性快速性心律失常。结果:59.2%(71/120)患者f QRR阳性。f QRS最常见于下壁导联(81.7%)。QTc间期(443.90±38.59)ms。平均随访13.4个月,窦性心律维持率为42.5%。多因素Cox回归分析表明,f QRS阳性(HR=1.922,95%CI:1.151~3.210,P=0.012)和QTc>448 ms(HR=1.982,95%CI 1.155~3.402,P=0.013)分别是术后复发的危险因素。f QRS和QTc联合能更好预测心房颤动术后复发。结论:f QRS和QTc延长是HCM合并心房颤动患者导管消融术后复发的独立预测因素。f QRS和QTc联合可用于预测该类患者心房颤动射频术后转归。     

右心室不同间隔部位起搏对左心室收缩功能的影响

目的 通过比较右心室心尖部及不同间隔部位（室间隔高位、中位、低位）起搏患者血浆N端B型利钠肽前体（NT-proBNP）水平、QRS时限,探讨右心室不同部位起搏对左心室收缩功能的影响.方法 选择植入VVI或DDD型起搏器患者122例,按照右心室不同起搏部位采用随机数字法分为4组：右心室心尖部起搏（RVAP）组、右心室间隔面起搏高位组（RVSP1组）、右心室间隔面起搏中位组（RVSP2组）、右心室间隔面起搏低位组（RVSP3组）,观察4组患者起搏器植入术前及术后18个月心电图QRS时限、血浆NT-proBNP水平、左心室射血分数（LVEF）、左心室舒张末期容积（LVEDV）以及出现心血管事件等指标.结果 所有患者均顺利完成导线和起搏器植入,并完成随访.心血管事件发生率比较,RVSP2组较RVAP组显著减低（4.5％对40％,P＜0.05）.术后RVAP组QRS时限最宽,RVSP2组起搏QRS时限最窄,差异有统计学意义（P＜0.05）;术后18个月患者RVAP、RVSP1、RVSP3组NTproBNP均有不同程度增加,其中RVAP组最高（P＜0.05）;4组患者LVEDV术后18个月与术前比较,RVSP3组与RVAP组有不同程度增加（P＜0.05）,其中RVAP组增加显著（P＜0.05）;术后18个月RVSP组LVEF均无显著减低（P＞0.05）,而RVAP组显著减低（P＜0.05）.结论 选择右心室中位间隔部起搏,起搏QRS时限最窄,患者NT-proBNP水平低,可能为起搏器植入患者理想的起搏部位.     

慢性心衰患者QRS时程和新发房颤的相关性研究

目的 探讨慢性心衰患者QRS时程（QRSd）增宽对新发房颤的预测价值.方法 选择患有心衰但无房颤病史的患者1098例,将其分为三组：QRSd≤120 ms、120 ms〈QRSd〈150 ms及QRSd≥150 ms组,随访跟踪各组新发房颤的概率.通过二元分析和多元logistic回归分析探讨QRS时程和房颤新发概率之间的相关性.结果 对患者群体的统计表明,房颤的新发概率为35.7%.通过二元分析发现,房颤的新发概率存在组间差别（21.7%、35.9%、42.5%,P〈0.01）;进一步通过多元回归发现,QRS时程是独立的影响因素.结论 QRS是慢性心衰患者新发房颤的独立预测因素.     

QRS波时限对起搏器依赖患者心脏功能的影响

目的:观察右心室起搏QRS波时限对起搏器依赖患者心脏功能的影响。方法:选取在我院诊断为Ⅲ度房室传导阻滞并行永久性右心室起搏的患者112例,以起搏QRS波时限将患者分为A组(起搏QRS波时限<190ms)和B组(起搏QRS波时限≥190ms),并对每例患者进行临床评估和心脏彩色多普勒超声检查,动态随访心脏功能,以随访期间出现明显心功能下降为终点,观察起搏QRS波时限与心脏功能的关系。同时根据随访期间是否出现心功能下降将患者分为心功能下降组(Y组)和心功能无下降组(N组),并进行各因素与心功能下降之间的单因素分析,取P<0.1的因素纳入Logistic回归模型,寻找影响起搏器依赖患者心功能的因素。结果:平均随访(45.46±23.00)个月,40例(28.57%)出现明显心功能下降,其中,A组24例(27.27%),B组16例(66.67%),2组间差异有统计学意义(P=0.0004),Y组的起搏QRS波时限较N组明显延长[(176.58±22.71)∶(159.74±20.23)ms,P<0.0001]。多元Logistic逐步回归分析结果显示,左心室舒张末期内径增大、射血分数下降、左束支传导阻滞、起搏QRS波时限≥190ms、年龄及起搏时间是起搏器依赖患者心功能下降的危险因素。结论:起搏QRS波时限延长是心脏功能下降和心力衰竭发生的危险因素,可以作为起搏器依赖患者起搏后心脏功能下降的预测指标。除此之外,左心室增大、左束支传导阻滞、射血分数降低、年龄及起搏时间也是起搏器依赖患者心脏功能下降的危险因素。     

QRS Fragmentation and the Risk of Sudden Cardiac Death in MADIT II

QRS Fragmentation and the Risk of Sudden Cardiac Death in MADIT II. Background: QRS fragmentation (fQRS) has been reported as a useful ECG parameter in predicting mortality in high‐risk postinfarction patients. Its prognostic value for sudden cardiac death (SCD) and ventricular arrhythmias in ischemic cardiomyopathy (ICM) remains unknown. Methods: MADIT II enrollment 12‐lead ECGs were analyzed for fQRS defined as RSR’ patterns (≥1 R’ or notching of S or R wave) in patients with a normal QRS duration and >2 notches on the R or S wave in patients with abnormal QRS duration, present in 2 contiguous leads. Exclusion criteria included a paced rhythm and an uninterpretable or incomplete ECG. Study endpoints included SCD, SCD or appropriate implantable cardioverter defibrillator (ICD) shock, and total mortality (TM). Results: Of the 1,232 ECGs reviewed, 1,040 were of suitable quality for fQRS analysis. QRS fragmentation was found in 33% of patients in any leads, in 10% of patients in anterior leads, in 8% of patients in lateral leads and in 21% of patients in inferior leads. Anterior and lateral location of QRS fragmentation was not associated with follow‐up events. Inferior location of fQRS was found to be predictive of SCD/ICD shock (hazard ratio [HR] 1.46, P = 0.032), SCD (HR 2.05, P = 0.007), and TM (HR 1.44, P = 0.036). This association was driven primarily by the increase in events found in LBBB patients: SCD/ICD shock (HR 2.05, P = 0.046), SCD (HR 4.24, P = 0.002), and TM (HR 2.82, P = 0.001). Conclusions: Fragmented QRS, especially identified in inferior leads, is predictive of SCD, SCD or appropriate ICD shock, and all‐cause mortality in patients with ICM. Identifying inferior fQRS in patients with LBBB is of particular prognostic significance and should reinforce the use of ICD therapy in this high‐risk group. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1343‐1348, December 2012)     

ECG changes in patients with acute ethanol intoxication

Objectives. To assess how ethanol in potential lethal serum concentrations affects features of the ECG that may be associated with cardiac arrhythmias. Design. We included 84 patients, who were hospitalised with assumed acute ethanol intoxication. In the emergency room resting ECG was recorded and blood was collected for serum osmolality measurement used as a proxy for ethanol level. Thirty-two also had ECG recorded at discharge. Twenty-seven hospitalised patients without known alcohol ingestion served as controls. ECG segment durations were compared with controls and related to intoxication level. Results. In subjects with moderately elevated to high serum osmolality, the P wave and QTc intervals were prolonged compared with sober subjects. P wave, PR, QRS and QTc intervals were longer when the subjects had high blood ethanol levels (at admission) than at discharge (p-values: 0.0001, 0.0002, 0.010 and < 0.0001 for P wave, PR, QRS and QTc intervals. n = 32). Conclusions. Ethanol at high to very high blood concentration causes several changes in the ECG that might be associated with increased risk of arrhythmias.     

High triglyceride level is associated with severe coronary artery disease in hypertensive subjects

Background. The contribution of triglycerides (TG) to the extent of coronary artery disease (CAD) in hypertensive patients remained unclear. Methods. Consecutive 821 (aged 64.5±11.5 years, 482 males) hypertensive patients undergoing coronary angiography were included. The relationship of TG levels (<150 vs. ≥150 mg/dl) to the extent of CAD in all patients was examined by multiple logistic regression, adjusting for other CAD risk factors. In the lipid group, low levels of HDL were also adjusted. Results. Higher levels of TG were found in subjects with severe CAD compared to those with no or minimal CAD. The adjusted odds ratios for high levels of TG in the severe CAD subgroup versus the no or minimal CAD subgroup were 5.20 (95% CI, 3.13 to 8.63) in all patients and 7.51 (95% CI, 3.19 to 17.65) in the lipid group. Conclusions. High levels of TG are strong clinical markers of greater extent of CAD in hypertensive subjects undergoing coronary angiography. The results may have clinical relevance for physicians in therapeutic decision making.     

心电图碎裂QRS波与高血压患者左心室舒张功能的相关性研究

目的:本文拟探索心电图碎裂QRS波与高血压患者左心室舒张功能障碍之间的相关性。方法:前瞻性分析冠状动脉造影正常的102例原发性高血压患者资料。碎裂QRS波群定义为至少两个相关导联QRS波群(<120 ms)呈RSR'型(≥1个R'波、或S波、R波存在切迹),并无典型束支传导阻滞的心电图图形。所有患者经超声心动图检查并记录左心室舒张功能。左心室舒张功能不全分为两型:非严重型(1级舒张功能不全)和严重型(≥2级舒张功能不全)。结果:52例患者出现碎裂QRS波,为碎裂QRS波阳性组,50例无碎裂QRS波,为碎裂QRS波阴性组。两组基线情况基本相同。碎裂QRS波阳性组出现严重舒张功能不全比例明显高于碎裂QRS波阴性组(P<0.05)。碎裂QRS波阳性组高血压病程明显长于碎裂QRS波阴性组(P<0.05)。心电图中碎裂QRS波是左心室重度舒张期功能障碍的指标(OR=9.2;95%CI=3.4~31.4;P=0.009)。结论:心电图碎裂QRS波的存在可提示高血压患者左心室舒张功能严重不全。     

Optimal sensed atrio-ventricular interval determined by paced QRS morphology

BACKGROUND: In cardiac resynchronization therapy (CRT), the atrio-ventricular (AV) and interventricular (VV) intervals have to be optimized. For maximal optimization, the paced and sensed AV intervals have to be determined. We hypothesized that the morphology of the paced QRS complex at the optimal paced AV interval (PAV) can be used to determine the optimal sensed AV (SAV) interval in patients with normal AV conduction. PATIENTS AND METHODS: In 16 patients with implanted CRT devices, the optimal PAV and V-V interval were determined by invasive measurement of left ventricle (LV) dP/dt(max). A 12-lead electrocardiogram (ECG) was recorded at the optimum setting. Subsequently, during atrial sensing ventricular pacing, the SAV interval was changed until the QRS morphology was identical to the morphology at the optimal PAV interval. The optimal SAV interval was verified by repeated measurement of LV dP/dt(max). RESULTS: By optimization of the PAV and VV interval, the LV dP/dt(max) increased from 639 +/- 204 to 789 +/- 223 mmHg/s (+23%; P = 0.0000002). The optimized PAV was 149 +/- 19 ms; the optimized SAV was 100 +/- 20 ms and the corresponding LV dP/dt(max) at this interval was 774 +/- 204 ms (+21%; P = 0.000004). LV dP/dt(max) at optimized SAV - 20 ms and optimized SAV + 20 ms was 747 +/- 213 mmHg/s (P = 0.00004) and 751 +/- 203 mmHg/s (P = 0.0000003), respectively. The mean difference in optimized PAV and optimized SAV was 49 +/- 17 ms, ranging from 20 to 80 ms. CONCLUSIONS: The QRS morphology at optimized PAV can be used as a template to determine the optimal SAV, provided that the patient has normal AV conduction.