Rate-related changes in QRS morphology in patients with fixed bundle branch block: implications for differential diagnosis of wide QRS complex tachycardia

Introduction. Determination of ventricular and supraventricular arrhythmias with left bundle branch block morphology (LBBB) seems to be one of the most complex diagnostic tasks when P waves are not clearly identifiable on 12-lead ECG. Previously described criteria for differential diagnosis of wide QRS arrhythmias had low accuracy especially for patients from various clinical groups and also those taking antiarrhythmic drugs. When patient’s clinical data, medical history or physical examination results are not available the number of misdiagnosis may increase leading to improper treatment. Therefore, development of new temporal and amplitude based characteristics of wide QRS complex arrhythmias with LBBB morphology in patients of any clinical groups is an important task.Methods. Twenty-eight consecutive patients with wide QRS premature beats and LBBB morphology identified by 24-hour and long-term ECG monitoring (ZAO “INCART”, Russia) were enrolled in the study. Fourteen patients had premature atrial contractions (PAC) and fourteen patients had premature ventricular contractions (PVC) during sinus rhythm. For each patient 10 typical single wide QRS complexes in 12 ECG leads were analyzed. The duration of QRS complexes, time intrinsic deflection (TID) and electrical axis of the heart were determined automatically in 12 leads ECG using KT Result 3 software (ZAO “INCART”, Russia). The experts assessed morphology of the QRS complexes and transition zone location in leads V1-V6. ROC analysis with optimal cut-off value level evaluation as well as calculation of sensitivity (SV), specificity (SP) and diagnostic accuracy (ACC) were performed for qualitative and quantitative assessment of diagnostic value of PAC and PVC amplitude and temporal characteristics. Comparison of diagnostic values of wide QRS complex morphological and temporal criteria was performed based on the AUC difference and the corresponding p-value assessment.Results. The results of study found out that V5, V1 leads were more informative for assessment of QRS complex morphology and duration while V1 and V4 leads were more informative for TID calculation in differential diagnosis of wide QRS complexes arrhythmias with LBBB morphology. PAC with aberrant conduction had the following characteristics: TID < 68 ms in V1 lead and TID < 62 ms in V4 lead; QRS < 136 ms; transition zone in the leads V5, V6; QS, rS or RS complexes (with S> R) with low-amplitude r/R waves in leads V1-V4; electric axis of the heart less than 80° in standard leads. In all cases PVCs were characterized by QRS > 160 ms and TID > 88 ms in V1-V6 leads.Conclusions. New various criteria which can improve differential diagnosis of wide QRS complexes with LBBB morphology were identified in this study. These criteria should be tested in a larger group of patients with various forms of wide QRS complex arrhythmias and different PVC localizations including information of structural heart diseases due to the small sample size in this study.Conflicts of Interest: Viktor M. Tikhonenko - CEO (Director General) of the Institute of Cardiology Technics (INCART), Saint-Petersburg, Russia.

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Right Bundle Branch Block: Current Considerations

Current Cardiology Reviews ◽

10.2174/1573403x16666200708111553 ◽

2020 ◽

Vol 16 ◽

Author(s):

Takanori Ikeda

Keyword(s):

Differential Diagnosis ◽

Clinical Practice ◽

Electrical Activity ◽

Right Bundle Branch Block ◽

Qrs Complex ◽

Bundle Branch Block ◽

S Waves ◽

Characteristic Appearance ◽

Normal Sequence ◽

Purkinje System

: RBBB, a pattern seen on the 12-lead ECG, results when normal electrical activity in the His-Purkinje system is interrupted by some reason. The normal sequence of activation is altered in RBBB, with a resultant characteristic appearance on the ECG manifest by a widened QRS complex and changes in the directional vectors of the R and S waves. This ECG pattern is often seen in clinical practice and generally regarded as benign. The anatomy, epidemiology, causes, symptoms, ECG findings and diagnosis, differential diagnosis in ECG, treatment, complications, prognosis, with respect to RBBB is outlined here, demonstrating some typical ECGs of RBBB.

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Diagnosis and Ablation of Fascicular Tachycardia

Asia Pacific Cardiology ◽

10.15420/apc.2011:3:1:67 ◽

2011 ◽

Vol 3 (1) ◽

pp. 67

Author(s):

Akihiko Nogami ◽

Keyword(s):

Ventricular Tachycardia ◽

Right Bundle Branch Block ◽

Axis Deviation ◽

Exit Site ◽

Rare Form ◽

Bundle Branch Block ◽

Diagnosis And Therapy ◽

Narrow Qrs ◽

Left Posterior ◽

Qrs Morphology

Verapamil-sensitive fascicular ventricular tachycardia (VT) is the most common form of idiopathic left VT. According to the QRS morphology and the successful ablation site, left fascicular VT can be classified into three subgroups: left posterior fascicular VT, whose QRS morphology shows right bundle branch block (RBBB) configuration and superior axis (common form); left anterior fascicular VT, whose QRS morphology shows RBBB configuration and right-axis deviation (uncommon form), and upper septal fascicular VT, whose QRS morphology shows narrow QRS configuration and normal or right-axis deviation (rare form). Posterior and anterior fascicular VT can be successfully ablated at the posterior or anterior mid-septum with a diastolic Purkinje potential during VT or at the VT exit site with a fused pre-systolic Purkinje potential. Upper septal fascicular VT can also be ablated at the site with diastolic Purkinje potential at the upper septum. Recognition of the heterogeneity of this VT and its unique characteristics should facilitate appropriate diagnosis and therapy.

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Evaluation of the Specificity of Morphological Electrocardiographic Criteria for the Differential Diagnosis of Wide QRS Complex Tachycardia in Patients With Intraventricular Conduction Defects

Circulation ◽

10.1161/01.cir.96.10.3527 ◽

1997 ◽

Vol 96 (10) ◽

pp. 3527-3533 ◽

Cited By ~ 31

Author(s):

Teresa Alberca ◽

Jesús Almendral ◽

Petra Sanz ◽

Aureliano Almazan ◽

Jose Luis Cantalapiedra ◽

...

Keyword(s):

Differential Diagnosis ◽

Qrs Complex ◽

Intraventricular Conduction

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Abstract P64: Right Ventricular Outflow Septal Pacing as Cardiac Resynchronization Therapy in Patients with Right Bundle-Branch Block: Results in 62 Patients

Circulation Cardiovascular Quality and Outcomes ◽

10.1161/circoutcomes.4.suppl_2.ap64 ◽

2011 ◽

Vol 4 (suppl_2) ◽

Author(s):

Phillip E Schrumpf ◽

Michael Giudici ◽

Deborah Paul ◽

Roselyn Krupa ◽

Cynthia Meirbachtol

Keyword(s):

Cardiac Resynchronization Therapy ◽

Right Ventricular ◽

Right Bundle Branch Block ◽

Left Ventricular ◽

Cardiac Resynchronization ◽

Qrs Complex ◽

Resynchronization Therapy ◽

Ventricular Performance ◽

Bundle Branch Block ◽

Qrs Duration

Background: Cardiac resynchronization therapy has been shown to improve left ventricular performance in patients with left ventricular dysfunction and a left-sided interventricular conduction delay. This is performed by placing a pacing lead on the lateral left ventricular wall to stimulate the area normally stimulated by the left bundle branch. In patients with right bundle branch block (RBBB), pacing the right bundle branch could also result in resynchronization. Previous studies have shown that right ventricular outflow septal (RVOS) pacing does, in fact, utilize the native conduction system. Methods: 62 consecutive patients, 46 male/16 female, aged 75 +/− 10.5 yr, with RBBB and indications for pacing, underwent RVOS lead placement using commercially available pacing systems. The patients subsequently underwent bedside A-V optimization to achieve the narrowest QRS duration and most “normal” QRS complex. Echocardiography was performed to evaluate changes in wall motion comparing baseline with optimal pacing. Results: Baseline mean QRS duration 146 +/− 20.9 ms Optimized mean QRS duration 111 +/− 20.5 ms Average decrease in QRS duration -35 +/− 21.5 ms p < 0.001 Echocardiography demonstrated improvement in septal contraction abnormalities. Conclusions: 1) RVOS pacing in RBBB patients can significantly narrow the QRS complex on ECG. 2) Septal contraction abnormalities due to RBBB can be improved with RVOS pacing and optimal A-V timing. 3) Further studies are warranted to evaluate this therapy in a heart failure population.

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Abstract 13286: Non-Specific Intraventricular Conduction Delay and Risk of Sudden Death

Circulation ◽

10.1161/circ.130.suppl_2.13286 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Audrey Uy-Evanado ◽

Carmen Teodorescu ◽

Kyndaron Reinier ◽

Kumar Narayanan ◽

Harpriya Chugh ◽

...

Keyword(s):

Sudden Cardiac Death ◽

General Population ◽

Left Bundle Branch Block ◽

Cardiac Death ◽

Conduction Delay ◽

Bundle Branch Block ◽

Intraventricular Conduction ◽

Qrs Morphology ◽

Qrs Duration ◽

Intraventricular Conduction Delay

Introduction: We and others have reported an independent association between prolonged QRS duration and risk of sudden cardiac death (SCD) in the general population. Left and right bundle branch block have been studied previously, but there is little information regarding non-specific intraventricular conduction delay and risk of SCD. Hypothesis: Completed conduction defects, including non-specific IVCD, are associated with increased SCD risk. Methods: Sudden cardiac death cases and controls from an ongoing large population based study in the Northwestern US (2002 to 2010) were included if age ≥ 35 years with a non-paced 12-lead ECG (recorded prior and unrelated to SCD in cases). QRS morphology was subcategorized as normal, intermediate [left anterior fascicular block (LAFB), left posterior fascicular block (LPFB), and incomplete right or left bundle branch block (IRBBB/ILBBB)] or completed conduction defects [left bundle branch block (LBBB), right bundle branch block (RBBB), or nonspecific intraventricular conduction delay (IVCD)]. Comparisons were conducted using chi-square tests for categorical variables and independent samples t-tests for continuous variables. Logistic regression was used to evaluate the association of QRS morphology with SCD. Results: We evaluated 761 SCD cases (64% male) and 539 controls (65% male). Cases were significantly older (69.7 vs 66.3 years, p<0.0001) with greater QRS duration (102 vs. 98 ms, p=0.001). For conduction categories, intermediate or completed conduction defects were significantly more common in cases whereas normal QRS morphology was more common among controls (p=0.01). And for specific morphology overall, QRS morphology patterns differed between cases and controls (p=0.03); abnormal QRS morphologies were more frequent in cases than controls except for LAFB. After adjustment for age and gender, however, only a finding of LBBB or non-specific IVCD remained a significant predictor of SCD [OR 1.34 (95% CI 1.03-1.75)]. Conclusions: LBBB and non-specific IVCD, but not RBBB, are significant predictors of SCD in the general population. These findings contribute to the utility of the 12-lead EKG for SCD risk stratification.

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Differentiating the QRS Morphology of Posterior Fascicular Ventricular Tachycardia From Right Bundle Branch Block and Left Anterior Hemiblock Aberrancy

Circulation Arrhythmia and Electrophysiology ◽

10.1161/circep.117.005074 ◽

2017 ◽

Vol 10 (9) ◽

Cited By ~ 7

Author(s):

Yoav Michowitz ◽

Oholi Tovia-Brodie ◽

Ishai Heusler ◽

Avi Sabbag ◽

Michael Rahkovich ◽

...

Keyword(s):

Ventricular Tachycardia ◽

Right Bundle Branch Block ◽

Bundle Branch Block ◽

Qrs Morphology ◽

Anterior Hemiblock

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Abstract 16382: The Surface ECG May Provide Information About Left Ventricular Systolic Function in Patients With Right Bundle Branch Block

Circulation ◽

10.1161/circ.142.suppl_3.16382 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Anshul Gupta ◽

Behzad B Pavri

Keyword(s):

Right Bundle Branch Block ◽

Visual Recognition ◽

Visual Analysis ◽

Systolic Function ◽

Left Ventricular ◽

Lv Function ◽

Qrs Complex ◽

Bundle Branch Block ◽

Transition Group ◽

Surface Ecg

Introduction: In patients (pts) with right bundle branch block (RBBB) and heart failure, assessment of left ventricular (LV) function is vital to management, but echocardiograms (ECHO) may not always be readily available. We studied the utility of using the Superimposed Median Format (available on digital ECG systems) in assessing LV function. This format allows visual recognition of change in dV/dT when rapid initial impulse propagation over the left bundle branch (LBB) and LV Purkinje network transitions to slower muscle-to-muscle propagation to the right ventricle (RV) in the setting of RBBB. Hypothesis: With a normal LBB and healthy LV myocardium, the transition from rapid forces to slower depolarization would occur in the 1 st half of the QRS complex ( Early Transition Group - ET) whereas in patients with abnormal LV function, this transition would occur in the 2 nd half (Late Transition Group - LT) of the QRS complex. Methods: Digital superimposed median format ECGs of 108 pts with RBBB were analyzed. Pts were divided into 2 groups: ET or LT. See figure. LVEFs were obtained from ECHO. LVEF ≥ 50% was considered normal. Results: ET: n = 69. LT: n = 39. Mean QRS durations were not different in the 2 groups. ET pts were more likely to have normal LVEF (p < 0.01). See figure. PPV of ET in predicting LVEF ≥50% = 90%; NPV = 71%. Accuracy = 82%. Conclusions: These data, if confirmed, suggest that in pts with RBBB, visual analysis of the QRS complex from the surface ECG using the superimposed median format may provide valuable clues about LV systolic function, and may be clinically useful when ECHO are not readily available.

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