Prevalence Of Left Bundle Branch Block Research Articles

Prevalence, clinical and angiography of Coronary Artery Disease in patients with chest pain with left bundle branch block in Iraqi Centers of Heart Disease

Introduction and Aim: Left bundle branch block (LBBB), is seen on the electrocardiograms, when the His-Purkinje system disrupts the normal sequence of activation is changed in the left bundle branch block, leading to specific appearance on the electrocardiograms. Left bundle branch blocks usually occur in patients associated with advanced heart conduction disorders. In this study we aimed to study the prevalence of significant CAD in patients with chest pain and left bundle branches block sent to invasive coronary angiography and study clinical and angiography with distribution of CAD risk factors in our study population. Methodology: This investigation is a single center retrospective cohort study that included 400 patients who underwent coronary angiography with left bundle branch block on their ECGs. The study was carried out in the Iraqi Center for Heart Disease between April 2017 and May 2022. Data regarding their age, gender, related risk factors, electrocardiography, echo and left ventricular function was noted. Data was subjected to statistical analysis using the Minitab program. Results: The prevalence of CAD was 41% among the 400 patients who had LBBB. Demographic data showed age, hypertension, and diabetes mellitus to be a risk factor associated with CAD. The related anatomy of the left bundle branch block in 98 patients showed single or multiple coronary artery disease and likely reduced ejection fraction (<50%). Conclusion: The prevalence of LBBB is more common in males than in females. The biggest risk factor for cardiovascular disease in those with LBBB and coronary artery disease is hypertension, which is followed by age and diabetes mellitus. Thus, coronary angiography should be used in cardiac tests to identify CAD in individuals with LBBB.

Vulnerable Phase of Acute Heart Failure and its Association with Hospital Readmissions Reduction Program.

To determine the prevalence, characteristics and association with prognosis of left bundle branch block (LBBB) in 3 different cohorts of patients with acute heart failure (AHF).We retrospectively analyzed 12,950 patients with AHF who were included in the EAHFE (Epidemiology Acute Heart Failure Emergency), RICA (National Heart Failure Registry of the Spanish Internal Medicine Society), and BASEL-V (Basics in Acute Shortness of Breath Evaluation of Switzerland) registries. We independently analyzed the relationship between baseline and clinical characteristics and the presence of LBBB and the potential association of LBBB with 1-year all-cause mortality and a 90-day postdischarge combined endpoint (Emergency Department reconsultation, hospitalization or death). The prevalence of LBBB was 13.5% (95% confidence interval: 12.9%–14.0%). In all registries, patients with LBBB more commonly had coronary artery disease and previous episodes of AHF, were taking chronic spironolactone treatment, had lower left ventricular ejection fraction and systolic blood pressure values and higher NT-proBNP levels. There were no differences in risk for patients with LBBB in any cohort, with adjusted hazard ratios (95% confidence interval) for 1-year mortality in EAHFE/RICA/BASEL-V cohorts of 1.02 (0.89–1.17), 1.15 (0.95–1.38) and 1.32 (0.94–1.86), respectively, and for 90-day postdischarge combined endpoint of 1.00 (0.88–1.14), 1.14 (0.92–1.40) and 1.26 (0.84–1.89). These results were consistent in sensitivity analyses.Less than 20% of patients with AHF present LBBB, which is consistently associated with cardiovascular comorbidities, reduced left ventricular ejection fraction and more severe decompensations. Nonetheless, after taking these factors into account, LBBB in patients with AHF is not associated with worse outcomes.

Prevalence, Related Factors and Association of Left Bundle Branch Block With Prognosis in Patients With Acute Heart Failure: a Simultaneous Analysis in 3 Independent Cohorts

To determine the prevalence, characteristics and association with prognosis of left bundle branch block (LBBB) in 3 different cohorts of patients with acute heart failure (AHF). We retrospectively analyzed 12,950 patients with AHF who were included in the EAHFE (Epidemiology Acute Heart Failure Emergency), RICA (National Heart Failure Registry of the Spanish Internal Medicine Society), and BASEL-V (Basics in Acute Shortness of Breath Evaluation of Switzerland) registries. We independently analyzed the relationship between baseline and clinical characteristics and the presence of LBBB and the potential association of LBBB with 1-year all-cause mortality and a 90-day postdischarge combined endpoint (Emergency Department reconsultation, hospitalization or death). The prevalence of LBBB was 13.5% (95% confidence interval: 12.9%-14.0%). In all registries, patients with LBBB more commonly had coronary artery disease and previous episodes of AHF, were taking chronic spironolactone treatment, had lower left ventricular ejection fraction and systolic blood pressure values and higher NT-proBNP levels. There were no differences in risk for patients with LBBB in any cohort, with adjusted hazard ratios (95% confidence interval) for 1-year mortality in EAHFE/RICA/BASEL-V cohorts of 1.02 (0.89-1.17), 1.15 (0.95-1.38) and 1.32 (0.94-1.86), respectively, and for 90-day postdischarge combined endpoint of 1.00 (0.88-1.14), 1.14 (0.92-1.40) and 1.26 (0.84-1.89). These results were consistent in sensitivity analyses. Less than 20% of patients with AHF present LBBB, which is consistently associated with cardiovascular comorbidities, reduced left ventricular ejection fraction and more severe decompensations. Nonetheless, after taking these factors into account, LBBB in patients with AHF is not associated with worse outcomes.

Prevalence, Incidence and Prognostic Implications of Left Bundle Branch Block in Patients with Chronic Coronary Syndromes (From the CLARIFY Registry)

Left Bundle Branch Block (LBBB) is a frequently encountered electrical abnormality in patients with chronic (more than 3 months after myocardial infarction, or evidence of coronary artery disease with ischemia) coronary syndromes (CCS), but its prognostic significance remains unclear. We aimed to describe the prevalence, incidence and five-year outcomes of LBBB in outpatients with CCS using the CLARIFY registry. Main outcome was a composite of CV death, MI or stroke. Secondary outcomes included all cause death, hospitalization for heart failure (HF) and permanent pacemaker implantation. Among 23.544 patients with available information regarding LBBB status at baseline, 1.041 (4.4%) had LBBB at baseline and 1.015 (4.5%) patients developed a new LBBB during 5-year follow-up. In multivariate analysis, LBBB at baseline was not associated with the composite outcome of CV death, MI or stroke (HR 1.06, 95% CI [0.86 - 1.31], p = 0.67) or the risk of all-cause death (HR 1.07, 95% CI [0.87 - 1.32], p = 0.52) but was significantly associated with a higher risk of hospitalization for HF (HR 1.50, 95% CI [1.21 - 1.88], p < 0.001) and permanent pacemaker implantation (HR 2.11, 95% CI [1.45 - 3.07], p < 0.001). The main factors associated with new-onset LBBB were male sex (HR 0.8 [0.66-0.98], p = 0.028) history of atrial fibrillation (HR 1.29, 95% CI [1.01 - 1.64], p = 0.04), CABG (HR 1.27, [1.08 - 1.51], p = 0.004) and MI (HR 1.19, 95% CI [1.01 - 1.40], p = 0.034). In conclusion, in a contemporary registry of outpatients with CCS, the prevalence of LBBB was 4.4% and the additional 5-years incidence 6.2%. LBBB, in itself, was not associated with a higher risk of major adverse cardiovascular events or all cause mortality. It was however an independent predictor of risk of hospitalization for heart failure and permanent pacemaker implantation.

Prevalence, incidence and prognostic implications of left bundle branch block in patients with stable coronary artery disease. An analysis from the CLARIFY registry

The prevalence, and prognostic implication of left bundle branch block (LBBB) patients with stable coronary artery disease (CAD) is unknown. To describe the prevalence, incidence and prognostic implications of LBBB in patients with stable CAD. CLARIFY is an international registry of more than 30.000 patients with stable CAD. LBBB was defined as a QRS complex > 120 milliseconds. Patients with previous pacemaker implantation or defibrillator were excluded. The primary outcome was a composite of cardiovascular (CV) Death, MI or stroke, and secondary outcomes included hospitalization for heart failure (HF) or the need for pacemaker implantation. From the 23.457 patients with available data, 1.041 (4.4%) had LBBB at baseline and 1.237 (5.3%) during 5-year follow-up. Only 21 patients with newly diagnosed LBBB overtime, had a documented MI the same year. Compared to patients without LBBB, patients with LBBB had a higher risk profile regarding age (67.2 ± 10.1 versus 63.6 ± 10.4 years, P < 0.0001), history of coronary artery bypass grafting (29.2% vs. 23.7%, P < 0.0001), diabetes (35.1% vs. 28.4%, P < 0.0001), and HF (25.2% vs. 16.8%, P < 0.0001). In multivariate analysis there was no difference in the rate of primary outcome between LBBB or no-LBBB patients (adjusted HR 1.04, 95% CI 0.85–1.29). Patients with LBBB had a higher rate of pacemaker implantation (adjusted HR 2.21, 95% CI 1.55–3.15, P < 0.0001) and hospitalization for HF (adjusted HR 1.53, 95% CI 1.25–1.88, P < 0.0001) ( Table 1 , Fig. 1 ). The prevalence of LBBB in patients with stable CAD was 4.4% and 5.3% with 5-year follow-up. The majority of newly diagnosed LBBB were not contemporary of myocardial infarction. LBBB was not associated with a higher rate of major adverse cardiovascular events, but with a higher risk of pacemaker implantation and hospitalization for heart failure. This is the first study reporting such results in a broad population of stable CAD patients.

2211Prevalence, incidence and prognostic implications of left bundle branch block in patients with stable coronary artery disease. an analysis from the CLARIFY registry

Abstract Background The prevalence, and prognostic implication of left bundle branch block (LBBB) in general population and patients admitted for acute myocardial infarction (MI) as been extensively studied. However, data are scarce about patients with stable coronary artery disease (CAD) and it remains unclear whether LBBB is only a marker of a severe cardiomyopathy or an independent predictor of events in these patients. Purpose We aimed to describe the prevalence, incidence and prognostic implications of LBBB in patients with stable CAD. Additionally, we aimed to describe the incidence of newly diagnosed LBBB that occurred without recent myocardial infarction. Methods CLARIFY is an international registry of more than 30.000 patients with stable CAD. LBBB was collected at baseline and at each follow-up visit, and patients were considered to have LBBB if the length of the QRS complex was of more than 120 milliseconds. Patients with previous pacemaker implantation of internal cardiac defibrillator were excluded. The primary outcome was a composite of cardiovascular (CV) Death, MI or stroke, and secondary outcomes included hospitalization for heart failure (HF) or the need for pacemaker implantation. Results From the 23.457 patients with available data regarding LBBB status, 1.041 (4.4%) had LBBB at baseline and 1.237 (5.3%) had at least one LBBB assessed during 5-year follow-up. Only 21 patients with newly diagnosed LBBB overtime, had a documented MI the same year. Compared to patients without LBBB, patients with LBBB had a higher risk profile regarding age (67.2±10.1 versus 63.6±10.4 years, p&lt;0.0001), history of coronary artery bypass grafting (29.2% vs 23.7%, p&lt;0.0001), diabetes (35.1% vs 28.4%, p&lt;0.0001), and HF (25.2% vs 16.8%, p&lt;0.0001) (Table). In unadjusted analysis, patients with LBBB had a higher risk of primary outcome (13.4% vs 8.7%, p&lt;0.0001) and each secondary outcome. In multivariate analysis taking into account several possible confounders, there was no difference in the rate of CV death, MI or stroke between LBBB or no-LBBB patients (adjusted HR 1.04, 95% CI 0.85–1.29). However, patients with LBBB had a higher rate of pacemaker implantation (adjusted HR 2.21, 95% CI 1.55–3.15, p&lt;0.0001) and hospitalization for HF (adjusted HR 1.53, 95% CI 1.25–1.88, p&lt;0.0001) (Figure). Outcomes according to LBBB status Conclusion The prevalence of LBBB in patients with stable CAD was 4.4% and 5.3% with 5-year follow-up. The overwhelming majority of newly diagnosed LBBB were not contemporary of documented myocardial infarction. LBBB was not associated with a higher rate of major adverse cardiovascular events, including all cause mortality but with a higher risk of pacemaker implantation and hospitalization for heart failure. To our knowledge this is the first study reporting such results in a broad population of stable CAD patients. Acknowledgement/Funding None

Clinical Profile of the Patients with Newly Detected Left Bundle Branch Block in the Outpatient Department

Objective: The purpose of this study was to evaluate cardiac features associated with newly detected left bundle branch block (LBBB) in the outpatient department. Methods: A total of 57 patients with LBBB pattern were evaluated using electrocardiography (ECG). Patients were assessed based on their sex, age, detailed history, and cardiovascular symptoms. Cardiac investigations including ECG and echocardiography were performed. Results:The study included 30 (52.6%) males and 27 (47.5%) females, aged between 35 and 80 years. Dyspnoea (35.1%) and chest pain (22.8%) were the most common symptoms. 54.4% were hypertensive and 17.5% were diabetics. 28% had Left ventricular systolic dysfunction, and 24.5% had aortic valve disease. Left ventricular hypertrophy without any other structural heart disease was present in 28% of the patients. Only 24.5% patients presented with LBBB had a structurally normal heart in echocardiography. Myocardial performance index in echocardiography was abnormal in LBBB irrespective of the presence of structural heart disease. Conclusion: The prevalence of LBBB was found to increase with age and had slight male preponderance. Dyspnoea on effort was the most common presenting complaint, followed by chest pain and incidental detection of ECG abnormality. Most of the patients were hypertensive. Only 24.5% patients with LBBB had a structurally normal heart. MPI was abnormally high in the presence of LBBB despite having a normal left ventricular ejection fraction.

Prevalence and clinical significance of left bundle branch block according to classical or strict definition criteria in permanent pacemaker patients.

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. We assessed the prevalence and prognostic significance of LBBB according to classical (QRS duration ≥120ms) and strict criteria in permanent pacemaker patients. 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. 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. 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.

Asymptomatic Left Bundle Branch Block Predicts New-Onset Congestive Heart Failure and Death From Cardiovascular Diseases.

BackgroundLeft bundle branch block (LBBB) has been proposed as a risk factor for cardiovascular morbidity and mortality. We sought to characterize the strength of these associations in a population without preexisting clinical heart disease.MethodsThe association between LBBB and new-onset congestive heart failure (CHF) or death from cardiovascular diseases was examined in 1,688 participants enrolled in the SPPARCS study who were free of known CHF or previous myocardial infarction. SPPARCS is a community-based cohort study in residents of Sonoma, California that are > 55 years. Medical history and 12-lead ECGs were obtained every 2 years for up to 6 years of follow-up. LBBB at enrollment or year 2 was considered “baseline” and assessed as a predictor of CHF and cardiovascular death ascertained at years 4 and 6.ResultsThe prevalence of LBBB at baseline was 2.5% (n = 42). During 6 years of follow-up, 70 (4.8%) people developed new CHF. Incidence of CHF was higher in patients with LBBB than in participants without LBBB. This association persisted after controlling for potential confounders (odds ratio (OR): 2.85; 95% confidence interval (CI): 1.01 - 8.02; P = 0.047). A higher mortality from cardiovascular diseases was also found in participants with LBBB after adjusting for potential confounders (OR: 2.35, 95%CI: 1.02 - 5.41; P = 0.044).ConclusionsLBBB in the absence of a clinically detectable heart disease is associated with new-onset CHF and death from cardiovascular diseases. Further study is warranted to determine if additional diagnostic testing or earlier treatment in patients with asymptomatic LBBB can decrease cardiovascular morbidity or mortality.

Proportion of candidates for cardiac resynchronization therapy.

Biventricular pacing has been used as an adjunct to standard heart failure therapy in symptomatic patients with left bundle branch block (LBBB). Estimates of the number of patients for whom this treatment is appropriate are unavailable, but are of clinical and socioeconomic importance. LBBB combined with a low (< 0.35) ejection fraction was found in 7,121 consecutive patients referred for elective diagnostic angiography in 1996 through 2000 from a total population of about 125,000 residents. Patients with LBBB (n = 289, 4%) had lower ejection fractions (0.53 +/- 0.23) in comparison with patients without LBBB (P < 0.0001). The ejection fraction was < 0.35 in 558 (8%) patients. LBBB was combined with a low ejection fraction in 96 (1.4%) patients (i.e., 19 patients per year and about 15 patients per year per 100,000 residents). Of these 96 patients, 80 had normal sinus rhythm, 82 had mitral regurgitation (grade > II), 86 were < 75 years of age, and 68 had coronary artery disease. Holter recordings performed in 47 of 96 patients showed nonsustained VT in 28 (60%). LBBB, low ejection fraction, sinus rhythm, and age < 75 years were found in 71 (1%) patients (i.e., 11 patients per year per 100,000 residents). The prevalence of LBBB combined with severely impaired left ventricular ejection function is about 1-2% in patients who undergo cardiac catheterization. The authors estimate that biventricular pacing might be considered as an adjunct to standard heart failure therapy in five to ten patients per year per 100,000 residents in industrial countries. About half of these patients are potential candidates for implantation of cardioverter defibrillators combined with permanent pacing.