-
JACC. Cardiovascular Imaging Mar 2020
Topics: Arrhythmias, Cardiac; Bundle-Branch Block; Cardiac Resynchronization Therapy; Electrocardiography; Humans; Mitral Valve Insufficiency; Papillary Muscles
PubMed: 32139036
DOI: 10.1016/j.jcmg.2019.09.025 -
Journal of the American College of... Mar 2020
Topics: Bundle-Branch Block; Cardiac Resynchronization Therapy; Heart Failure; Humans
PubMed: 32216912
DOI: 10.1016/j.jacc.2020.02.027 -
Journal of the American College of... Dec 2018Idiopathic or iatrogenic left bundle branch block (LBBB) is a unique model of electro-mechanical ventricular dyssynchrony with concordant changes in electrical... (Review)
Review
Idiopathic or iatrogenic left bundle branch block (LBBB) is a unique model of electro-mechanical ventricular dyssynchrony with concordant changes in electrical activation sequence and mechanical ventricle synchronization. In chronic animal models, isolated LBBB induces structural remodeling with progressive left ventricular (LV) dysfunction. Most abnormalities can be reverted after cardiac resynchronization therapy (CRT). In humans, 2 principal models of LBBB dyssynchronopathy can be observed: the chronic model of isolated LBBB and an acute iatrogenic model of new-onset LBBB after aortic valve interventions. Although epidemiological evidence and clinical data need to be strengthened, there is a strong presumption that they may lead to LBBB-induced cardiomyopathy and benefit from CRT to prevent progression to heart failure. A large cohort study with prospective follow-up would be required to better define actual incidence, evolution over time, and predisposing factors. Parallel randomized CRT clinical trials should be conducted in selected at-risk populations: namely, patients with persistent LBBB after transcatheter aortic valve replacement.
Topics: Animals; Bundle-Branch Block; Cardiac Resynchronization Therapy; Disease Models, Animal; Humans; Iatrogenic Disease; Models, Cardiovascular; Ventricular Dysfunction, Left
PubMed: 30545456
DOI: 10.1016/j.jacc.2018.09.069 -
Heart and Vessels Jul 2022Left bundle branch area pacing (LBBAP) has developed in an effort to improve cardiac resynchronization therapy (CRT). We aimed to compare the long-term clinical outcomes...
Left bundle branch area pacing (LBBAP) has developed in an effort to improve cardiac resynchronization therapy (CRT). We aimed to compare the long-term clinical outcomes between LBBAP and biventricular pacing (BIVP) in patients with heart failure (HF) and complete left bundle branch block (CLBBB). Consecutive patients with HF and CLBBB requiring CRT received either LBBAP or BIVP were recruited at the Second Affiliated Hospital of Nanchang University from February 2018 to May 2019. We assessed their implant parameters, electrocardiogram (ECG), clinical outcomes at implant and during follow-up at 1, 3, 6, 12, and 24 months. Forty-one patients recruited including 21 for LBBAP and 20 for BIVP. Mean follow-up duration was 23.71 ± 4.44 months. LBBAP produced lower pacing thresholds, shorter procedure time and fluoroscopy duration compared to BIVP. The QRS duration was significantly narrower after LBBAP than BIVP (129.29 ± 31.46 vs. 156.85 ± 26.37 ms, p = 0.005). Notably, both LBBAP and BIVP significantly improved LVEF, LVEDD, NYHA class, and BNP compared with baseline. However, LBBAP significantly lowered BNP compared with BIVP (416.69 ± 411.39 vs. 96.07 ± 788.71 pg/ml, p = 0.007) from baseline to 24-month follow-up. Moreover, patients who received LBBAP exhibited lower number of hospitalizations than those in the BIVP group (p = 0.019). In addition, we found that patients with moderately prolonged left ventricular activation time (LVAT) and QRS notching in limb leads in baseline ECG respond better to LBBAP for CLBBB correction. LBBAP might be a relative safe and effective resynchronization therapy and as a supplement to BIVP for patients with HF and CLBBB.
Topics: Bundle of His; Bundle-Branch Block; Cardiac Pacing, Artificial; Cardiac Resynchronization Therapy; Electrocardiography; Heart Failure; Humans; Treatment Outcome
PubMed: 35088204
DOI: 10.1007/s00380-021-02016-5 -
Annals of Noninvasive Electrocardiology... Jul 2019The criteria for left bundle branch block have gained growing interest in the last few years. In this overview, we discuss diagnostic and prognostic aspects of different... (Review)
Review
The criteria for left bundle branch block have gained growing interest in the last few years. In this overview, we discuss diagnostic and prognostic aspects of different criteria. It was already shown that stricter criteria, including longer QRS duration and slurring/notching of the QRS, better identify responders to cardiac resynchronization therapy. We also include aspects of ST/T concordance and discordance and vectorcardiography, which could further improve in the fine-tuning of the left bundle branch criteria.
Topics: Bundle-Branch Block; Humans; Vectorcardiography
PubMed: 30938470
DOI: 10.1111/anec.12644 -
Pacing and Clinical Electrophysiology :... Aug 2021Isolated left bundle branch block (LBBB) aberrancy is exceedingly rare in the young and its clinical and genetic determinants remain poorly characterized. Furthermore,... (Review)
Review
Isolated left bundle branch block (LBBB) aberrancy is exceedingly rare in the young and its clinical and genetic determinants remain poorly characterized. Furthermore, there is conflicting data on its natural history in the pediatric age group patients. We report the rare phenotype of isolated typical LBBB aberrancy in two healthy children, one of whom carried a likely pathogenic mutation in the coding exon 1 of NKX2-5 (p.Q22R, c.65A > G, rs201442000). Our findings suggest that isolated LBBB aberrancy could be non-progressive in some children, at least in the short term. However, given the paucity of data on this entity, we recommend continued long-term surveillance.
Topics: Adolescent; Bundle-Branch Block; Diagnosis, Differential; Echocardiography; Electrocardiography; Exercise Test; Female; Humans; Magnetic Resonance Imaging; Male
PubMed: 33835496
DOI: 10.1111/pace.14243 -
Journal of Electrocardiology 2021QRS duration and morphology including left bundle branch block (LBBB) are the most widely used electrocardiogram (ECG) markers for assessing ventricular dyssynchrony and...
Association between vectorcardiographic QRS area and incident heart failure diagnosis and mortality among patients with left bundle branch block: A register-based cohort study.
BACKGROUND
QRS duration and morphology including left bundle branch block (LBBB) are the most widely used electrocardiogram (ECG) markers for assessing ventricular dyssynchrony and predicting heart failure (HF). However, the vectorcardiographic QRS area may more accurately identify delayed left ventricular activation and HF development.
OBJECTIVE
We investigated the association between QRS area and incident HF risk in patients with LBBB.
METHODS
By crosslinking data from Danish nationwide registries, we identified patients with a first-time digital LBBB ECG between 2001 and 2015. The vectorcardiographic QRS area was derived from a 12‑lead ECG using the Kors transformation method and grouped into quartiles. The endpoint was a composite of HF diagnosis, filled prescriptions for loop diuretics, or death from HF. Cause-specific multivariable Cox regression was used to compute hazard ratios(HR) with 95% confidence intervals(CI).
RESULTS
We included 3316 patients with LBBB free from prior HF-related events (median age, 72 years; male, 40%). QRS area quartiles comprised Q1, 36-98 μVs; Q2, 99-119 μVs; Q3, 120-145 μVs; and Q4, 146-295 μVs. During a 5-year follow-up, 31% of patients reached the composite endpoint, with a rate of 39% in the highest quartile Q4. A QRS area in quartile Q4 was associated with increased hazard of the composite endpoint (HR:1.48, 95%CI:1.22-1.80) compared with Q1.
CONCLUSIONS
Among primary care patients with newly discovered LBBB, a large vectorcardiographic QRS area (146-295 μVs) was associated with an increased risk of incident HF diagnosis, filling prescriptions for loop diuretics, or dying from HF within 5-years.
Topics: Aged; Bundle-Branch Block; Cardiac Resynchronization Therapy; Cohort Studies; Electrocardiography; Heart Failure; Humans; Male; Treatment Outcome
PubMed: 34547542
DOI: 10.1016/j.jelectrocard.2021.09.002 -
Canadian Journal of Rural Medicine :... 2015
Topics: Bundle-Branch Block; Electrocardiography; Humans; Male
PubMed: 26160517
DOI: No ID Found -
Clinical Cardiology Jun 2017Previous studies have shown that the presence of left bundle branch block (LBBB) is associated with an increased risk of cardiac mortality and heart failure (HF)....
BACKGROUND
Previous studies have shown that the presence of left bundle branch block (LBBB) is associated with an increased risk of cardiac mortality and heart failure (HF). Recently, new criteria to define strict LBBB have been proposed: QRS duration ≥140 ms for men and ≥130 ms for women, along with mid-QRS notching or slurring in ≥2 contiguous leads.
HYPOTHESIS
We assessed the prevalence and prognostic significance of LBBB according to classical (QRS duration ≥120ms) and strict criteria in permanent pacemaker patients.
METHODS
We retrospectively enrolled 723 consecutive patients who had undergone single- or dual-chamber pacemaker implantation at the study center from July 2002 to December 2014. Patients with a left ventricular ejection fraction ≤35% or a prior diagnosis of HF were excluded.
RESULTS
LBBB was reported in 54 (7%) patients, and strict-LBBB in 15 (2%) patients. During a median follow-up of 48 months (range, 18-92 months), 147 (20%) patients reached the combined endpoint of death or HF hospitalization. Patients with LBBB and those with strict-LBBB displayed significantly higher rates of death or HF hospitalization (log-rank test, all P < 0.0001). In particular, strict-LBBB was associated with the worst outcome. The presence of LBBB according to classical definition criteria (hazard ratio [HR] = 1.98, confidence interval [CI]: 1.23-3.19, P = 0.005) and to strict criteria (HR = 2.20; CI: 1.04-4.65; P = 0.039) were both confirmed as independent predictors of death or HF hospitalization after adjustment for relevant clinical covariates.
CONCLUSIONS
Among patients who had undergone standard pacemaker implantation, the prevalence of LBBB was 7% according to classical definition criteria and 2% according to strict criteria. The presence of LBBB, and particularly of strict-LBBB, at the baseline predicted a poor outcome in terms of death or HF hospitalization.
Topics: Aged; Bundle-Branch Block; Electrocardiography; Female; Follow-Up Studies; Humans; Italy; Male; Pacemaker, Artificial; Prevalence; Prognosis; Retrospective Studies; Stroke Volume; Time Factors; Ventricular Function, Left
PubMed: 28294356
DOI: 10.1002/clc.22673 -
European Heart Journal. Acute... Jun 2013Our aim was to investigate if patients with suspected myocardial infarction (MI) and a new or presumed new left bundle branch block (nLBBB) were treated according to the... (Comparative Study)
Comparative Study
BACKGROUND
Our aim was to investigate if patients with suspected myocardial infarction (MI) and a new or presumed new left bundle branch block (nLBBB) were treated according to the ESC reperfusion guidelines and to compare them with patients having a previously known LBBB (oLBBB). Furthermore, we investigated the prevalence of ST-segment concordance in this population.
METHODS
Retrospective data was collected from the Swedeheart registry for patients admitted to the cardiac care unit at Örebro University Hospital with LBBB and suspected MI during 2009 and 2010. The patients were divided in two age groups; <80 or ≥80 years and analysed for LBBB chronicity (nLBBB or oLBBB), MI, and reperfusion treatment. We also compared our data with the national Swedeheart database for 2009.
RESULTS
A total of 99 patients fulfilled the inclusion criteria. A diagnosis of MI was significantly more common in the group ≥80 years compared to the group <80 years (53.8 vs. 25%, p=0.007). The rate of MI was similar in the groups with nLBBB and oLBBB (33 and 37% respectively, p=0.912). Of the 36 patients with a final diagnosis of MI, only eight (22%) had nLBBB. Reperfusion treatment, defined as an acute coronary angiography with or without intervention, was significantly more often performed in patients with nLBBB compared to patients with oLBBB (42 vs. 8%, p<0.001). The rate of MI and reperfusion treatment did not differ between our institution and the Swedish national data. ST-concordance was present in only two cases, one of which did not suffer an MI.
CONCLUSIONS
The proportion of patients receiving reperfusion treatment was low, but higher in nLBBB, reflecting a partial adherence to the guidelines. We found no correlation between LBBB chronicity and MI. Furthermore, only a minority of the MIs occurred in patients with nLBBB. ST-concordance was found in only one of 36 MI cases, indicating lack of sensitivity for this test.
Topics: Aged; Aged, 80 and over; Bundle-Branch Block; Chronic Disease; Female; Guideline Adherence; Humans; Male; Myocardial Infarction; Myocardial Revascularization; Percutaneous Coronary Intervention; Practice Guidelines as Topic; Retrospective Studies
PubMed: 24222829
DOI: 10.1177/2048872613483589