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Clinical Cardiology Oct 2015The prognostic significance of right bundle branch block (RBBB) is inconsistent across studies. We aimed to assess the association between RBBB (in general population... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The prognostic significance of right bundle branch block (RBBB) is inconsistent across studies. We aimed to assess the association between RBBB (in general population and patients with heart disease) and risk of all-cause mortality, cardiac death, acute myocardial infarction (MI), and heart failure (HF).
HYPOTHESIS
RBBB may be associated with increased risk of death.
METHODS
PubMed, EMBASE, and the Cochrane Library up to February 2015 were searched for prospective cohort studies that reported RBBB at baseline and all-cause mortality, cardiac death, MI, and HF at follow-up. A meta-analysis of published data was undertaken primarily by means of fixed-effects models.
RESULTS
Nineteen cohort studies including 201 437 participants were included with a mean follow-up period ranging from 1 to 246 months. For general population with RBBB, the pooled adjusted hazard ratio (HR) for all-cause mortality was 1.17 (95% confidence interval [CI]: 1.03-1.33) compared with no BBB. General population with RBBB had an increased risk of cardiac death (HR: 1.43, 95% CI: 1.17-1.74). For patients with RBBB and acute MI, the pooled risk ratio was 2.31 (95% CI: 2.13-2.49) for in-hospital mortality, 2.85 (95% CI: 2.46-3.30) for 30-day mortality, and 1.96 (95% CI: 1.59-2.42) for longer-term mortality. For acute HF patients, the pooled risk ratio of all-cause mortality was 1.11 (95% CI: 1.06-1.16), and for chronic HF patients it was 1.75 (95% CI: 1.38-2.22).
CONCLUSIONS
Right bundle branch block is associated with an increased risk of mortality in general population and patients with heart disease.
Topics: Bundle-Branch Block; Cause of Death; Chi-Square Distribution; Disease Progression; Heart Failure; Humans; Myocardial Infarction; Odds Ratio; Prognosis; Prospective Studies; Risk Assessment; Risk Factors; Time Factors
PubMed: 26436874
DOI: 10.1002/clc.22454 -
The Israel Medical Association Journal... Dec 2019
Topics: Aged; Aged, 80 and over; Aortic Valve; Aortic Valve Stenosis; Bundle-Branch Block; Electrocardiography; Female; Humans; Male; Pacemaker, Artificial; Transcatheter Aortic Valve Replacement
PubMed: 31814348
DOI: No ID Found -
Europace : European Pacing,... Feb 2023Left bundle branch area pacing (LBBAP) is a recent technique aiming at preservation of physiological ventricular electrical activation. Our goal was to assess mechanical...
Left bundle branch area pacing in patients with baseline narrow, left, or right bundle branch block QRS patterns: insights into electrocardiographic and echocardiographic features.
AIMS
Left bundle branch area pacing (LBBAP) is a recent technique aiming at preservation of physiological ventricular electrical activation. Our goal was to assess mechanical synchrony parameters in relation to electrocardiographic features during LBBAP performed in routine practice.
METHODS AND RESULTS
From June 2020 to August 2021, all patients of our institution with permanent pacemaker implantation indication were eligible for LBBAP. A 'qR' pattern in V1 and a delay from pacing spike to the peak of the R-wave in V6 < 80 ms defined a successful LBBAP. Electrocardiogram and echocardiography were performed during spontaneous rhythm and LBBAP: left ventricular mechanical synchrony (LVMS) parameters using 2D Speckle tracking and interventricular mechanical delay (IVMD) were collected. LBBAP was attempted with success in 134/163 patients (82.2%). During LBBAP, the mean QRS width was 104 ± 12 ms. In patients with left bundle branch block (n = 47), LBBAP provided a significant decrease of QRS width from 139 ± 16 to 105 ± 12 ms (P < 0.001) with reduction of LVMS (53 ± 21 vs. 90 ± 46 ms, P = 0.009), and IVMD (14 ± 13 vs. 49 ± 18 ms, P < 0.001). In patients with right bundle branch block (n = 38), LBBAP led to a significant decrease of QRS width from 134 ± 14 to 106 ± 13 ms (P < 0.001) with no effect on LVMS and a reduction of IVMD (17 ± 14 vs. 50 ± 16 ms, P < 0.001).
CONCLUSION
LBBAP in routine practice preserved intra-ventricular mechanical synchrony in patients with narrow and RBBB QRS and improved asynchrony parameters in patients with LBBB.
Topics: Humans; Bundle-Branch Block; Cardiac Pacing, Artificial; Heart Conduction System; Electrocardiography; Echocardiography; Arrhythmias, Cardiac; Bundle of His
PubMed: 36480437
DOI: 10.1093/europace/euac223 -
Journal of the American Heart... Oct 2020
Topics: Bundle-Branch Block; Cardiovascular Diseases; Electrocardiography; Humans; Prognosis
PubMed: 32924752
DOI: 10.1161/JAHA.120.018987 -
Journal of the American College of... Mar 1986A cohort of 1,960 white men aged 40 to 56 years without initial apparent heart disease and with 11 years of annual rest electrocardiograms and 20 year mortality data was...
A cohort of 1,960 white men aged 40 to 56 years without initial apparent heart disease and with 11 years of annual rest electrocardiograms and 20 year mortality data was followed in the Chicago Western Electric Company Study. Incomplete right bundle branch block was found in 134 men (6.8%) at entry. During follow-up, 222 men developed such block, an incidence rate of 13.6%. Left axis deviation of -30 degrees or less was more frequent in men with than in those without incomplete block at entry (8.2 versus 2.4%). Men with left axis deviation also had a higher incidence of incomplete right bundle branch block. Similarly, men developing incomplete block had a significantly greater risk of developing left axis deviation. The associations between incomplete block and left axis deviation were unrelated to age and body weight. Men with incomplete block had a significantly greater likelihood of developing complete right bundle branch block. The 11 year incidence rate of complete block was 5.1% for men with baseline incomplete block and 0.7% for those without. Complete block developed in 2 of 220 incident cases of incomplete block but in none of the 440 control men matched by age and duration of follow-up. Although incomplete right bundle branch block was not related to an increased risk of death in 20 years from coronary heart disease and cardiovascular diseases, the study data suggest that such block is frequently a manifestation of primary abnormality of the cardiac conduction system in middle-aged men.
Topics: Actuarial Analysis; Adult; Bundle-Branch Block; Cardiovascular Diseases; Chicago; Coronary Disease; Electrocardiography; Follow-Up Studies; Humans; Male; Middle Aged; Prognosis; Prospective Studies; Risk; Smoking
PubMed: 3950228
DOI: 10.1016/s0735-1097(86)80458-2 -
Journal of the American College of... Mar 1987Eppinger and Rothberger in 1909 and 1910 first acknowledged the importance of the conduction system, yet a confusion of the pattern of left bundle branch block with... (Review)
Review
Eppinger and Rothberger in 1909 and 1910 first acknowledged the importance of the conduction system, yet a confusion of the pattern of left bundle branch block with right bundle branch block resulted which persisted for 25 years. In left bundle branch block, right ventricular endocardial activation begins before, and is often completed before, initiation of left ventricular endocardial activation. Most likely, right to left septal activation then follows, resulting in left ventricular endocardial activation. Although it is hazardous to make definitive diagnoses of infarction in the presence of left bundle branch block, clues do exist. Benign left bundle branch block is rare; usually disease becomes manifest. Electrocardiographic criteria of hypertrophy are not as helpful in older patients with chronic left bundle branch block (mainly because of the very high incidence of left ventricular hypertrophy) as in younger patients with block of nonatherosclerotic origin. Left bundle branch block is often associated with other abnormalities of the conduction system. Fascicular blocks may mask or mimic myocardial infarction. Left posterior fascicular block is most often an indicator of left ventricular myocardial deficit if right ventricular enlargement is eliminated. Mortality is higher in patients with associated left axis deviation than in those with a normal axis, although the incidence of progression of atrioventricular (AV) block is low. In symptomatic patients with prolonged His to ventricular intervals, the incidence of progression of AV block is higher (12%). Preexisting left bundle branch block in the absence of clinical evidence of heart disease is rare, yet carries with it a slightly increased mortality. Newly acquired left bundle branch block carries a 10-fold increase in mortality; the incidence of sudden death as the first manifestation of heart disease is increased 10-fold.
Topics: Bundle-Branch Block; Cardiomegaly; Electrocardiography; Electrophysiology; Heart Block; Heart Conduction System; Humans; Longitudinal Studies; Myocardial Infarction; Prognosis
PubMed: 2950157
DOI: 10.1016/s0735-1097(87)80065-7 -
PloS One 2018Duchenne muscular dystrophy (DMD) is an inherited myogenic disorder due to mutations in the dystrophin gene on chromosome Xp21.1. We designed this study to determine the...
BACKGROUND
Duchenne muscular dystrophy (DMD) is an inherited myogenic disorder due to mutations in the dystrophin gene on chromosome Xp21.1. We designed this study to determine the prevalence of left bundle branch block (LBBB), whether there is a relationship between LBBB and genetic pattern, and to assess predictive factors for acute cardiac events and mortality in adult DMD patients.
METHODS
We reviewed the charts of DMD followed at the Home Mechanical Ventilation Unit of the Raymond Poincare University Hospital.
RESULTS
A total of 121 patients, aged from 18 to 41 years have been included in our study. Median vital capacity (VC) was 12% [7; 19.5] of predicted. Almost all patients were on home mechanical ventilation (95%). LBBB was present in 15 patients (13%); among them, 10 disclosed exonic deletions. After a median follow up of 6 years, 21 patients (17%) experienced acute heart failure (AHF), 7 patients (6%) supraventricular arrhythmia, 3 patients (2.4%) ventricular tachycardia, 4 patients (3%) significant electrical disturbances. LBBB was significantly associated with cardiac events (OR = 12.7; 95%CI [3.78-42.7]; p <0.0001) and mortality (OR = 4.4; 95%CI [1.44-13.7]; p 0.009). Presence of residual dystrophin protein was not associated with significant less cardiac events. Age and LVEF were also predictive factors for cardiac events and mortality.
CONCLUSION
LBBB is relatively frequent in DMD and is a major predictive factor for cardiac events and mortality. Presence of residual dystrophin protein was not associated with a lower incidence of cardiac events.
Topics: Adult; Bundle-Branch Block; Female; Genetic Predisposition to Disease; Humans; Male; Muscular Dystrophy, Duchenne; Prevalence; Prognosis; Retrospective Studies; Young Adult
PubMed: 29304097
DOI: 10.1371/journal.pone.0190518 -
Journal of Cardiology Mar 2020Sub-analysis of the adaptive CRT (aCRT) trial demonstrated the potential benefits of the aCRT algorithm over conventional echo-guided bi-ventricular (BiV) pacing in... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Sub-analysis of the adaptive CRT (aCRT) trial demonstrated the potential benefits of the aCRT algorithm over conventional echo-guided bi-ventricular (BiV) pacing in patients with left bundle branch block (LBBB) with moderately wide QRS (120-149 ms) and normal atrioventricular (AV) conduction.
METHODS
Adoption of Adaptive CRT in Patients with Left Bundle Branch Block and Moderately Wide QRS (aCRT MID-Q, UMIN Clinical Trials Registry Number: 000022452) was a multicenter, prospective, randomized, double-blind study designed to investigate the superiority of the aCRT pacing algorithm compared to echo-guided BiV pacing in patients with moderately wide LBBB and normal AV conduction. The primary endpoint was the improvement in clinical composite score (CCS) at 6 months; the secondary endpoints were changes in left ventricular (LV) end-systolic volume, LV ejection fraction, New York Heart Association classification, 6-min walk distance, and quality of life from baseline to 6 months post-randomization; heart failure administration; all-cause mortality; and cardiac mortality within 12 months.
RESULTS
The trial was terminated prematurely after enrollment of 39 patients (aCRT arm; n = 17, echo-guided BiV arm; n = 22) because of lower than expected enrollment. In the intention-to-treat analysis, the improvement of CCS was achieved in 10 patients (59%) in the aCRT arm (n = 17) and 16 patients (73%) in the echo-guided BiV arm (n = 22, p = 0.36). For the secondary endpoint, only 6-min walk distance was significantly greater in the aCRT arm than in the echo-guided BiV arm, and no difference was observed in the echocardiographic parameters. Heart failure hospitalization-free survival was also not significantly different (p = 0.91). There was no death during the follow-up.
CONCLUSIONS
Improvement of CCS was similarly observed after aCRT and echo-guided BiV in CRT recipients with moderately wide LBBB and normal AV conduction. A prospective study is needed to explore the impact of CRT and pacing algorithm on Japanese patients with moderately wide LBBB.
Topics: Aged; Bundle-Branch Block; Cardiac Resynchronization Therapy; Double-Blind Method; Female; Heart Failure; Humans; Male; Middle Aged; Quality of Life; Ventricular Function, Left
PubMed: 31492516
DOI: 10.1016/j.jjcc.2019.08.003 -
JACC. Cardiovascular Imaging Sep 2021This study speculated that longitudinal strain curves in left bundle branch block (LBBB) could be shaped by the degree of LBBB-induced cardiac remodeling.
OBJECTIVES
This study speculated that longitudinal strain curves in left bundle branch block (LBBB) could be shaped by the degree of LBBB-induced cardiac remodeling.
BACKGROUND
LBBB independently affects left ventricular (LV) structure and function, but large individual variability may exist in LBBB-induced adverse remodeling.
METHODS
Consecutive patients with LBBB with septal flash (LBBB-SF) underwent thorough echocardiographic assessment, including speckle tracking-based strain analysis. Four major septal longitudinal strain patterns (LBBB-1 through LBBB-4) were discerned and staged on the basis of: 1) correlation analysis with echocardiographic indexes of cardiac remodeling, including the extent of SF; 2) strain pattern analysis in cardiac resynchronization therapy (CRT) super-responders; and 3) strain pattern analysis in patients with acute procedural-induced LBBB.
RESULTS
The study enrolled 237 patients with LBBB-SF (mean age: 67 ± 13 years; 57% men). LBBB-1 was observed in 60 (26%), LBBB-2 in 118 (50%), LBBB-3 in 29 (12%), and LBBB-4 in 26 (11%) patients. Patients at higher LBBB stages had larger end-diastolic volumes, lower LV ejection fractions, longer QRS duration, increased mechanical dyssynchrony, and more prominent SF compared with less advanced stages (p < 0.001 for all). Among CRT super-responders (n = 30; mean age: 63 ± 10 years), an inverse transition from stages LBBB-3 and -4 (pre-implant) to stages LBBB-1 and -2 (pace-off, median follow-up of 66 months [interquartile range: 32 to 78 months]) was observed (p < 0.001). Patients with acute LBBB (n = 27; mean age: 83 ± 5.1 years) only presented with a stage LBBB-1 (72%) or -2 pattern (24%).
CONCLUSIONS
The proposed classification suggests a pathophysiological continuum of LBBB-induced LV remodeling and may be valuable to assess the attribution of LBBB to the extent of LV remodeling and dysfunction.
Topics: Aged; Aged, 80 and over; Bundle-Branch Block; Cardiac Resynchronization Therapy; Electrocardiography; Female; Humans; Male; Middle Aged; Predictive Value of Tests; Treatment Outcome; Ventricular Function, Left; Ventricular Remodeling
PubMed: 33865764
DOI: 10.1016/j.jcmg.2021.02.019 -
JACC. Clinical Electrophysiology Jan 2022
Topics: Bundle of His; Bundle-Branch Block; Humans
PubMed: 35057981
DOI: 10.1016/j.jacep.2021.08.007