Intraventricular conduction disturbances

ESC CardioMed ◽  
2018 ◽  
pp. 345-358
Author(s):  
Antoni Bayés de Luna ◽  
Marcelo V. Elizari
Keyword(s):  
Left Bundle Branch Block ◽  
Clinical Implications ◽  
Bundle Branch Block ◽  
Intraventricular Conduction ◽  
Conduction Disturbances ◽  
Key Concepts ◽  
Ecg Criteria ◽  
Electrocardiogram Ecg

This chapter highlights the key concepts related to the electrocardiogram (ECG) diagnosis of intraventricular conduction disturbances, including right and left bundle branch block. In both cases, but especially in left bundle branch block, the chapter discusses the diagnosis when the block is at a proximal level and in the fascicles. This includes the ECG diagnosis of the superoanterior and inferoposterior fascicles of the left bundle (the hemiblocks). The possible diagnosis of the block of middle fibres (septal fascicle) of left bundle is briefly mentioned. Finally, the ECG criteria for the diagnosis of bifascicular and trifascicular block are described. In all cases, the most important clinical implications of each diagnosis are discussed.

Intraventricular conduction disturbances

ESC CardioMed ◽  
2018 ◽  
pp. 345-358
Author(s):  
Antoni Bayés de Luna ◽  
Marcelo V. Elizari
Keyword(s):  
Left Bundle Branch Block ◽  
Clinical Implications ◽  
Bundle Branch Block ◽  
Intraventricular Conduction ◽  
Conduction Disturbances ◽  
Key Concepts ◽  
Ecg Criteria ◽  
Electrocardiogram Ecg

This chapter highlights the key concepts related to the electrocardiogram (ECG) diagnosis of intraventricular conduction disturbances, including right and left bundle branch block. In both cases, but especially in left bundle branch block, the chapter discusses the diagnosis when the block is at a proximal level and in the fascicles. This includes the ECG diagnosis of the superoanterior and inferoposterior fascicles of the left bundle (the hemiblocks). The possible diagnosis of the block of middle fibres (septal fascicle) of left bundle is briefly mentioned. Finally, the ECG criteria for the diagnosis of bifascicular and trifascicular block are described. In all cases, the most important clinical implications of each diagnosis are discussed.

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

Circulation ◽  
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.

scholarly journals CLINICAL IMPLICATIONS OF NEW LEFT BUNDLE BRANCH BLOCK: SUB–ANALYSIS FROM THE PARTNER TRIAL

2013 ◽  
Vol 61 (10) ◽  
pp. E1870
Author(s):  
Tamim Nazif ◽  
Mathew Williams ◽  
Rebecca T. Hahn ◽  
Wilson Y. Szeto ◽  
Raj Makkar ◽  
...  
Keyword(s):  
Left Bundle Branch Block ◽  
New Left ◽  
Clinical Implications ◽  
Bundle Branch Block

scholarly journals Device therapy guided by implantable loop recorders: predictors of bradyarrhythmic events

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Cardoso ◽  
B Faria ◽  
P Von Hafe ◽  
G Dias ◽  
T Pereira ◽  
...  
Keyword(s):  
Diagnostic Yield ◽  
Clinical Predictors ◽  
Device Therapy ◽  
Bundle Branch Block ◽  
Intraventricular Conduction ◽  
Conduction Disturbances ◽  
Device Implantation ◽  
Unexplained Syncope ◽  
Implantable Loop Recorders

Abstract Background Implantable loop recorders (ILR) improved diagnostic yield in unexplained syncope patients (pts). Data on possible predictive factors for bradycardia requiring device implantation in these pts is limited. We aim to identify clinical predictors for device implantation due to a significant bradyarrhythmia in patients who underwent ILR insertion for the study of syncopal/presyncopal (S/pS) events. Methods Single-center retrospective study of patients who implanted an ILR for the study of unexplained S/pS episodes between 2013 and 2018. The primary endpoint was a documented bradyarrhythmia requiring device implantation during the follow-up. Results A total of 251 pts were included. Mean age was 68±15 years and 53% were female. The majority of pts (220; 88%) had normal ejection fraction. Fifty-two (21%) pts had atrial fibrillation (AF). Regarding basal electrocardiographic characteristics, 34 (14%) pts had 1st degree auriculo-ventricular block (AVB), 31 (12%) pts had left bundle branch block (L-BBB), 22 (9%) pts had R-BBB and 13 (5%) pts had bifascicular block. During a median follow-up of 20 (IQR 9–34) months, 74 (29%) pts required device implantation because of a significant bradyarrhythmia (92% pacemaker, 4% CRT, 4% ICD). Median duration from ILR until device implantation was 5 (IQR 1–10) months. The indications were sick-sinus-syndrome in 47 (64%) pts, advanced AV block in 23 (31%) pts and symptomatic slow AF in 4 (5%) pts. Patients who required device implantation were older (73±12 vs 66±15 years, p &lt;0.001), had more hypertension (73% vs 59% p=0.048), a higher prevalence of AF (34% vs 15% p=0.001) and a lower glomerular filtration rate (GFR&lt;60 ml/min: 32% vs 21%, p=0.047). They also had more 1st AVB (22% vs 11%, p=0.026) and intraventricular conduction disturbances (38% vs 25%, p=0.025). There was a trend for a higher device implantation in pts with concomitant 1st AVB and left anterior fascicular block (7% vs 2%, p=0.063) In a logistic regression model, age &gt;75 years (HR: 1.7; 95% CI: 1.1–2.8) and the presence of AF (HR: 1.8; 95% CI: 1.1–3.0) were independent predictors for device implantation. Conclusion An older age and the presence of AF were independent predictors for device therapy in pts who implanted an ILR for the study of S/pS. These factors may identify a higher risk group and should be considered in the initial workup of these pts. Funding Acknowledgement Type of funding source: None

scholarly journals Brugada syndrome masked by complete left bundle branch block. A clinical and functional study of its association with the p.1449Y>H SCN5A variant.

2021 ◽  
Author(s):  
Eduardo Arana-Rueda ◽  
Rosa Pezzotti ◽  
Alonso Pedrote ◽  
Juan Acosta ◽  
Manuel Frutos-López ◽  
...  
Keyword(s):  
Left Bundle Branch Block ◽  
Brugada Syndrome ◽  
Functional Study ◽  
Loss Of Function ◽  
Bundle Branch Block ◽  
Conduction Disturbances ◽  
Disease Penetrance ◽  
Functional Consequences ◽  
Patch Clamp Electrophysiology ◽  
Scn5a Gene

SCN5A gene variants are associated with both Brugada syndrome and conduction disturbances, sometimes expressing an overlapping phenotype. Functional consequences of SCN5A variants assessed by patch clamp electrophysiology are particularly beneficial for a correct pathogenic classification and are related to disease penetrance and severity. Here, we identify a novel SCN5A loss of function variant, p.1449Y>H, which presented with high penetrance and complete left bundle branch block, totally masking the typical findings on the electrocardiogram. We highlight the possibility of this overlap combination that makes impossible an electrocardiographic diagnosis and, through a functional analysis, associate the p.1449Y>H variant to SCN5A pathogenicity.

Sign in / Sign up

Export Citation Format

Share Document