左心室收缩功能不全并完全性左束支传导阻滞QRS时间与左心室质量的关系研究

目的 探讨收缩功能不全并完全性左束支传导阻滞患者QRS时间与左心室质量的关系. 方法 将57例左心室收缩功能不全并完全性左束支传导阻滞患者按QRS时间分为120～160ms(观察组,n=42)及>160ms(对照组,n=15)两组.常规超声心动描记术计算左心室质量.观察两组ORS时间与左心室质量的关系. 结果 两组患者左心室质量分别为(220.68±87.26)g、(322.46±92.69)g,差异有非常显著性意义(P<0.01).QRS时间与左心室质量呈正相关(r=0.28,P<0.05). 结论 收缩功能不全并完全性左束支传导阻滞患者QRS间期延长反映左心室质量增加.     

Idiopathic Left Ventricular Aneurysm: An Unusual Substrate of Ventricular Fibrillation and Ventricular Tachycardia

Idiopathic left ventricular aneurysm (LVA) is a very rare clinical condition. This article describes a patient with idiopathic LVA associated with episodes of ventricular tachycardia and ventricular fibrillation. Clinical and instrumental examinations did not reveal the pathogenesis of the aneurysm. The malignant clinical course suggests that an aggressive antiarrhythmic treatment, including ICD implantation, may be warranted.     

Bundle Branch Reentry Ventricular Tachycardia with Two Distinct Left Bundle Branch Block Morphologies

Bundle Branch Reentry VT with Two Morphologies. Introduction: Bundle branch reentry ventricular tachycardia (VT) is usually amenable to treatment with radiofrequency ablation. Different QRS morphologies during VT are possible when anterograde ventricular activation is over the left bundle branch. Manifestations of tbis reentrant tachycardia with more than one QRS morphology with anterograde activation via the right bundle have not been reported and would be unusual due to the more discrete anatomy of the right bundle branch. Methods and Results: An electropbysiologic study was conducted in a patient with dilated ventricle and diminished ventricular function with VT, Typical characteristics of bundle branch reentry were noted when VT was induced. The study was notable for the presence of a right bundle recording only during macroreentrant beats or VT and the distal location of the recording. Radiofrequency ablation was performed. Postablation stimulation again induced VT, proven to be of the same bundle branch reentry mechanism but of a different QRS morphology. A second ablation was required for complete ablation of this patient's bundle branch reentry VT. Conclusion: In bundle branch reentry utilizing the left bundle as the retrograde limb and the right bundle branch as the anterograde limb of the circuit, VT of more than one distinct morphology can be seen. Careful evaluation to assess for the persistence of VT of the same mechanism is necessary to ensure complete ablation of the reentrant circuit. Preexisting right bundle disease and a dilated heart with more dispersed distal right bundle branches may predispose to such a phenomenon.     

Fragmented QRS Is Associated with All‐Cause Mortality and Ventricular Arrhythmias in Patient with Idiopathic Dilated Cardiomyopathy

Background: Several studies have showed that fragmented QRS complexes (f ‐ QRS, defined as different RSR′ patterns) on a routine 12 ‐ lead electrocardiogram were associated with increased mortality and arrhythmic events in patients with coronary artery disease, but relatively little data were available regarding idiopathic dilated cardiomyopathy (IDCM). Objective: The purpose of this study was to evaluate the relationship between fragmentation of QRS and the combined end point of all‐cause mortality and ventricular arrhythmias in patients with IDCM. Methods: One hundred twenty‐eight patients with IDCM and left ventricular dysfunction (ejection fraction, EF ≤ 40%) were analyzed, respectively. According to QRS duration and the existence of f ‐ QRS on 12‐lead electrocardiograph (ECG), the study populations were divided into three groups: (1) the f ‐ QRS group (QRS <120 ms and with fragmented QRS, n = 51), (2) the wide QRS (wQRS) group (QRS ≥ 120 ms, n = 48), and (3) the nonfragmented QRS (non‐fQRS) group (QRS < 120 ms and without f ‐ QRS, n = 29). Results: During a mean follow‐up of 14 ± 5 months, 25 (19.5%) patients had deaths and ventricular arrhythmic events. The combined end point of all‐cause mortality and ventricular tachyarrhythmias was significantly higher in the f ‐ QRS and wQRS groups than the non‐fQRS group (23.5%, 25%, and 3.4%, respectively; P < 0.05 for both). Event‐free was significantly decreased in the f ‐ QRS group versus the non‐fQRS group (P = 0.02). Univaritae regression analysis revealed that f ‐ QRS was a stronger predictor of mortality and arrhythmic events in IDCM patients. Conclusion: f ‐ QRS on 12‐lead ECG has a high predictive value for the combined end point of all‐cause mortality and ventricular tachyarrhythmias in IDCM patients with left ventricular dysfunction. Ann Noninvasive Electrocardiol 2011;16(3):270–275     

健康成年人群碎裂QRS波群的检出与意义

目的:研究碎裂QRS波群(fragmented QRS, fQRS)在健康人群中的检出率、分布规律及临床意义.方法:前瞻性入选连续1 000例无症状的健康体检者(年龄18~65岁),采集其静息状态下的常规心电图.fQRS的定义为至少2个连续导联的QRS波群存在≥2个R波或者R波的波顶或S波的波谷出现切迹.通过Logistic多因素分析确定与fQRS检出相关的指标.结果:总计86例(8.6%)检出fQRS,其中男性占69.8%(60/86),平均每例的fQRS导联数目为(2.3±0.5)个.90.7%(78/86)的fQRS分布于下壁导联,另9.3%(8/86)分布于胸前导联.Logistic多因素分析显示,QRS时限偏长及额面心电轴<30°是健康成人常规心电图检出fQRS的独立相关因素.胸前导联呈现fQRS的导联(8例)均包含QRS移行所在导联.结论:①fQRS在健康成年人群中并不罕见,特别是在下壁导联;②健康成年人fQRS的产生似与轻度室内传导延缓和(或)平均心电轴有关.     

Diagnosis of Ventricular Aneurysm and Other Severe Segmental Left Ventricular Dysfunction Consequent to a Myocardial Infarction in the Presence of Right Bundle Branch Block: ECG Correlates of a Positive Diagnosis Made via Echocardiography and/or Contrast Ventriculography

Background: A diagnostic ECG sign of a ventricular aneurysm (VA) consequent to a myocardial infarction (MI) in the presence of complete left bundle branch block was recently described, and consists of the presence of ST‐segment elevation (+ST), instead of the expected ST‐segment depression (?ST), in leads V_4–6. Generally, complete right bundle branch block (RBBB) is associated with ?ST in ECG leads V_1–3. We hypothesized that stable +ST, instead of the expected ?ST in leads V_1–3 in patients with RBBB could be also diagnostic of a VA and other severe segmental left ventricular dysfunction (VA/SSD). Thus, this study was performed to explore the feasibility of using the ECG to diagnose a VA/SSD in the presence of RBBB, and to evaluate the determinants of such diagnosis. Methods: The frequency of +ST ≥1 mm in leads V_1–3 was assessed in patients with RBBB, prior MI, and a VA/SSD diagnosed by echocardiography and/or contrast left cine‐ventriculography. The ECG correlates for a positive or negative diagnosis of a VA/SSD were explored. Results: Out of 4197 files of our cohort of the Cardiology Clinic, RBBB was detected in 175 patients. Of these, 28 had an old MI, and had a VA/SSD diagnosed by ≥1 of noninvasive and/or invasive non‐ECG tests. Twenty‐one of these 28 patients had stable +ST in ≥1 of leads V_1–3 (Group 1), and 7 did not (Group 2). Thus, the sensitivity of this ECG criterion for the diagnosis of VA/SSD was 75%, and the specificity was 100% in this highly selective group. VA/SSD in the septal and anterior myocardial regions was more frequent in the patients of Group 1, than in the patients of Group 2 (P = 0.03 and 0.02, correspondingly). The number of myocardial territories involved with the VA/SSD, or the ejection fraction were not different in the two groups (P = 0.65 and 0.55, correspondingly). Conclusion: VA/SSD can be diagnosed in the presence of RBBB by the concordant to the QRS repolarization changes (+ST) in leads V_1–3. Positivity of this ECG marker for VA/SSD correlates with involvement of the septal or anterior myocardial regions, and represents mechanistically a superimposition of primary repolarization alterations, overcoming the secondary such changes.     

心电图QRS波振幅时间乘积诊断高血压左室肥厚的价值

心电图ＱＲＳ波振幅时间乘积诊断高血压左室肥厚的价值夏勇李东野曹延龄吴兰芬（徐州医学院附属医院心内科２２１００２）ＥｌｅｃｔｒｏｃａｒｄｉｏｇｒａｐｈｉｃＤｉａｇｎｏｓｉｓｏｆＬｅｆｔＶｅｎｔｒｉｃｕｌａｒＨｙｐｅｒｔｒｏｐｈｙｉｎＥｓｓｅｎｔｉａｌＨ...     

Catheter Ablation of the Left Bundle Branch for the Treatment of Sustained Bundle Branch Reentrant Ventricular Tachycardia

Sustained Bundle Branch Reentrant VT. Radiofrequency catheter ablation of the left bundle branch (LBB) was attempted in a patient with sustained bundle branch reentry. During sinus rhythm, the QRS had a complete LBB block pattern, and the LBB was activated retrogradely (transseptal). Ablation of the LBB eliminated inducibility of the tachycardia, while the QRS complex and the duration of the HV interval (70 msec) remained unchanged. Successful ablation of the LBB eliminated bundle branch reentry and yet maintained the anterograde conduction properties of the His-Purkinje system, obviating implantation of a permanent pacemaker.     

Mechanism of Abnormal Septal Motion in Left Bundle Branch Block: Role of Left Ventricular Wall Interactions and Myocardial Scar

ObjectivesThis study sought to investigate how regional left ventricular (LV) function modifies septal motion in left bundle branch block (LBBB).BackgroundIn LBBB, the interventricular septum often has marked pre-ejection shortening, followed by immediate relengthening (rebound stretch). This motion, often referred to as septal flash, is associated with positive response to cardiac resynchronization therapy (CRT).MethodsIn 10 anesthetized dogs, we induced LBBB by radiofrequency ablation and occluded the circumflex (CX) (n = 10) and left anterior descending (LAD) (n = 6) coronary arteries, respectively. Myocardial dimensions were measured by sonomicrometry and myocardial work by pressure-segment length analysis. In 40 heart failure patients with LBBB, including 20 with post-infarct scar and 20 with nonischemic cardiomyopathy, myocardial strain was measured by speckle-tracking echocardiography and myocardial work by pressure-strain analysis. Scar was assessed by cardiac magnetic resonance imaging with late gadolinium enhancement.ResultsDuring LBBB, each animal showed typical septal flash with pre-ejection shortening and rebound stretch, followed by reduced septal systolic shortening (p < 0.01). CX occlusion caused LV lateral wall dysfunction and abolished septal flash due to loss of rebound stretch (p < 0.0001). Furthermore, CX occlusion restored septal systolic shortening to a similar level as before induction of LBBB and substantially improved septal work (p < 0.001). LAD occlusion, however, accentuated septal flash by increasing rebound stretch (p < 0.05). Consistent with the experimental findings, septal flash was absent in patients with LV lateral wall scar due to lack of rebound stretch (p < 0.001), and septal systolic shortening and septal work far exceeded values in nonischemic cardiomyopathy (p < 0.0001). Septal flash was present in most patients with anteroseptal scar.ConclusionsLV lateral wall dysfunction and scar abolished septal flash and markedly improved septal function in LBBB. Therefore, function and scar in the LV lateral wall should be taken into account when septal motion is used to evaluate dyssynchrony.     

碎裂QRS——还有多少谜团有待解开?

碎裂QRS(fQRS)是一项新近被广泛重视的无创心电学指标,其形成机制被认为是心肌瘢痕形成所致的传导延迟,常见于冠心病患者,但也可见于心肌病和先天性心脏病患者。此外,fQRS也是致心律失常性右室心肌病、Brugada综合征、非缺血性心肌病临床预后的重要心电图预测指标。fQRS虽然在心血管疾病高危患者的检出和预警方面有重要的临床应用价值,但相关的争议仍有很多。现对近年有关fQRS的研究进展和有待探讨的未知领域进行综述。     

左心室壁瘤的外科治疗

外科治疗左心室壁瘤可以有效保护心肌,改善病人预后。近年来,更注重在切除左心室壁瘤的同时,应尽可能恢复左室的正常形态。     

Distinct Electrocardiographic Form of Idiopathic Ventricular Arrhythmia Originating From the Left Bundle Branch

Most premature ventricular contractions (PVCs) arise from the right or left ventricular outflow tract. Some VPCs originate near the His‐bundle region. However, there remains a paucity of information on PVCs originating directly from the cardiac conduction system. We describe 2 cases with idiopathic frequent PVCs that were mapped directly to the left bundle branch itself. We also provide an anatomic‐based mapping and ablation approach for management of these uncommon and challenging arrhythmias. In both cases we were able to either eliminate or significantly suppress the ectopic source by applying radiofrequency at this location without causing any significant impairment of the atrioventricular conduction.     

Left Bundle Branch Block in Type 2 Diabetes Mellitus: A Sign of Advanced Cardiovascular Involvement

Objective: To evaluate left bundle branch block (LBBB) as an indicator of advanced cardiovascular involvement in diabetic (DM) patients by examining left ventricular systolic function and proteinurea. Methods: Data of 26 diabetic patients with left bundle branch block (DM with LBBB) were compared with data of 31 diabetic patients without left bundle branch block (DM without LBBB) and 18 nondiabetic patients with left bundle branch block (non‐DM with LBBB). The inclusion criteria were age >45 years, and diabetes mellitus type 2 of >5 years. Results: Mean ages of patients in DM with LBBB, DM without LBBB, and non‐DM with LBBB groups were 67 ± 8, 68 ± 10, and 65 ± 10 years, respectively (P = NS). Females were 65%, 61%, and 61%, respectively (P = NS). Left ventricular ejection fraction in DM with LBBB was significantly lower than in DM without LBBB and non‐DM with LBBB (30 ± 10% vs 49 ± 12% and 47 ± 8%, P < 0.01). Left ventricular end‐diastolic volume was significantly higher in DM with LBBB than in DM without LBBB and non‐DM with LBBB (188.6 ± 16.4 mL vs 147.5 ± 22.3 mL and 165.3 ± 15.2 mL, P < 0.03). Similarly, left ventricular end‐systolic volume was significantly higher in DM with LBBB than in DM without LBBB and non‐DM with LBBB (135.4 ± 14.7 mL vs 83.7 ± 9.5 mL and 96.6 ± 18.4 mL, P < 0.02). No statistically significant difference was seen in left atrial size. Proteinurea in DM with LBBB (79.4 ± 18.9 mg/dL) was significantly higher than in DM without LBBB (35.6 ± 8.5 mg/dL, P < 0.05) and non‐DM with LBBB (12 ± 3.5 mg/dL, P < 0.05); however, there was no significant difference in Hb A1c levels in DM with LBBB and DM without LBBB (9.01% vs 7.81%, P = NS). Conclusions: Left bundle branch block in diabetic patients indicates advanced cardiovascular involvement manifesting with more severe left ventricular systolic dysfunction and proteinurea compared to both diabetic patients without left bundle branch block and nondiabetic patients with left bundle branch block.     

Laughter‐Induced Left Bundle Branch Block

Laughter‐Induced LBBB. We present the case of a patient with ischemic heart disease and intermittent left bundle branch block, reproducibly induced by laughter. Following treatment of ischemia with successful deployment of a drug‐eluting stent, no further episodes of inducible LBBB were seen. Transient ischemia, exacerbated by elevated intrathoracic pressure during laughter, may have contributed to onset of this phenomenon. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1136‐1138, October 2012)