Bundle Branch Block Research Articles

Left Ventricular Outflow Tract Morphology as a Predictor of Conductance Disturbances Following Transcatheter Aortic Valve Replacement.

Conduction disturbances represent one of the most common complications following transcatheter aortic valve replacement (TAVR). We sought to investigate the role of left ventricular outflow tract (LVOT) morphology in the development of conduction disturbances following TAVR. Consecutive patients who underwent TAVR in our center were included. The ratio between the LVOT area and the aortic annulus area was calculated. Patients were then divided into 2 groups on the basis of this ratio: group 1, which included patients with an LVOT area/aortic annulus area ratio <0.9; and group 2, which included patients with an LVOT area/aortic annulus area ratio ≥0.9. The primary end point was to assess the relationship between LVOT shape and the rate of permanent pacemaker implantation following TAVR. A multivariable analysis was performed to identify predictors of permanent pacemaker implantation following TAVR. From January 2018 to December 2020, 276 patients were included. Ninety-one patients with tapered LVOT morphology were assigned to group 1 and the rest (n=185 patients), tubular LVOT or flared LVOT shape, to group 2. The mean age was 81.5±5.7 years and 57% were women. After adjusting by confounding factors, tapered morphology of the LVOT and prior right bundle-branch block were found to be independent predictors of permanent pacemaker implantation (hazard ratio [HR], 2.6 [95% CI, 1.2-5.7]; P=0.014; and HR: 4.3 [95% CI 2.4-7.6], P<0.001); at a median follow-up time of 15.5 (interquartile range, 15) months. A tapered-LVOT morphology was associated with increased risk for permanent pacemaker implantation. LVOT morphology may be an additional factor to consider when choosing prosthesis size.

Recovery of complete left bundle branch block in dilated cardiomyopathy after optimal heart failure treatment: a case report

Complete left bundle branch block (CLBBB) is a significant cardiac conduction abnormality often associated with dilated cardiomyopathy (DCM). This case report highlights the improvement in CLBBB and symptom relief through reverse cardiac remodeling in a patient diagnosed with DCM following an optimized heart failure treatment regimen consisting of an angiotensin-converting enzyme inhibitor, beta-blocker, and mineralocorticoid receptor antagonist. This case highlights the potential of electrical remodeling and conduction system improvement in patients with DCM receiving optimized medical therapy.

Abnormal recognition-assisted and onset-offset aware network for pathological wearable ECG delineation

Electrocardiogram (ECG) delineation is essential to the identification of abnormal cardiac status, especially when ECG signals are remotely monitored with wearable devices. The complexity and diversity of cardiac conditions generate numerous pathological ECG patterns, not only requiring the recognition of normal ECG but also addressing an extensive range of abnormal ECG patterns, posing a challenging task. Therefore, we propose an abnormal recognition-assisted network to integrate supplementary information on diverse ECG patterns. Simultaneously, we design an onset-offset aware loss to enhance precise waveform localization. Specifically, we establish a two-branch framework where ECG delineation serves as the target task, producing the final segmentation results. Additionally, the abnormal recognition-assisted network serves as an auxiliary task, extracting multi-label pathological information from ECGs. This joint learning approach establishes crucial correlations between ECG delineation and associated ECG abnormalities. The correlations enable the model to demonstrate sufficient generalization in the presence of diverse abnormal ECG patterns. Besides, onset-offset aware loss focuses intensively on wave onsets and offsets by applying biased weights to various waveform positions. This approach ensures a focus on precise localization, facilitating seamless integration into cross-entropy loss function. A large-scale wearable 12-lead dataset containing 4,913 signals is collected, offering an extensive range of ECG data for model training. Results demonstrate that our method achieves outstanding performance on two test datasets, attaining sensitivity of 94.97% and 94.27% and an error tolerance lower than 20 ms. Furthermore, our method is effective for various aberrant ECG signals, including ST-segment changes, atrial premature beats, and right and left bundle branch blocks.

Cardiomyopathy-Associated Chronic HeartFailure in Infants Aged

There have been few large-scale studies on the outcomes of cardiomyopathy-associated heart failure (HF) in infants aged <1 year. This study aimed to assess longitudinal echocardiographic outcomes of infants with HF secondary to cardiomyopathy who survived for >1 year. A prospective observational study following 327 infant patients up to 5 years in 2 large pediatric heart centers in Northern China between January 2010 and December 2018. A total of 236 (72.2%) patients had reduced left ventricular ejection fraction (LVEF) (HF with reduced ejection fraction group; LVEF <40%), 91 (27.8%) patients had midrange LVEF (HF with midrange ejection fraction group; LVEF ≥40% but <55%). LVEF improved significantly within the first year and remained stable in years 2 through 5 for both groups. The HF with midrange ejection fraction group had a higher rate of LVEF normalization (hazard ratio, 1.65; P<0.001). Baseline LVEF ≥40%, baseline left ventricular end-diastolic diameter Z score <7.8, the absence of left bundle-branch block, and the absence of β-blocker use were 4 independent favorable predictors for future LVEF normalization. A total of 62.4% of enrolled patients were diagnosed with left ventricular noncompaction. No significant difference in LVEF normalization was found among the different types of cardiomyopathy studied. A significant number of infants with cardiomyopathy who survived >1 year were found to improve with medical therapies during the first year of diagnosis. Poorer outcomes were associated with decreased LVEF and increased heart size at diagnosis baseline, the presence of left bundle-branch block and use of β blockers. The Northern Chinese pediatric population may have a high proportion of left ventricular noncompaction.

Cost-Effectiveness Ratio Analysis of LBBaP Versus BVP in Heart Failure Patients With LBBB.

For the initial treatment strategy for patients with cardiac resynchronization therapy (CRT) indications, whether to choose left bundle branch area pacing (LBBaP) or biventricular pacing (BVP) remains controversial. We aimed to investigate the cost-effectiveness ratio (CER) of LBBaP and BVP in heart failure (HF) patients with left bundle branch block (LBBB). This observational study included HF patients with LBBB who underwent successful LBBaP or BVP. The primary outcomes were echocardiographic response (left ventricular ejection fraction [LVEF] increase ≥5%), LVEF improvement, hospitalization costs, and CER (CER = cost/echocardiographic response rate). Secondary outcomes included other echocardiographic parameters, New York Heart Association (NYHA), N-terminal pro-B-type natriuretic peptide (NT-proBNP), pacemaker parameters, complications, ventricular arrhythmia (VA) events, HF hospitalization (HFH), and all-cause mortality. A total of 130 patients (85 LBBaP and 45 BVP) were included (65.6 ± 10.0 years, 70.77% men). The median follow-up period was 16(12,30), months. Compared with BVP, the LBBaP group showed a greater increase in LVEF (20.2%±11.8% vs. 10.5%±13.9%; p<0.001), higher echocardiographic response rate (86.1% vs. 57.8%; p<0.001), and lower hospitalization costs [$9707.7 (7751.2, 18,088.5) vs. $20,046.1 (18,840.1, 22,447.3); p<0.0001]. The CER was 112.7 and 346.8 in LBBaP and BVP, respectively. The incremental cost-effectiveness ratio (ICER = △cost/△echocardiographic response rate) was $-365.3/per 1% increase in effectiveness. LBBaP improved cardiac function more significantly than BVP. There were no significant differences in clinical outcomes. LBBaP-CRT is more cost-effective than BVP, offering greater LVEF improvement, higher echocardiographic response rates, lower hospitalization costs, and more significantly improved cardiac function. These findings need large randomized clinical trials for further confirmation.

Heart Rhythm Disturbances in Cardiac Surgery Patients with Coronary Artery Disease

The aim. To analyze arrhythmological complications in cardiac surgery patients with coronary artery disease (CAD). Materials and methods. This was a retrospective data analysis of 354 cardiac surgery patients with various forms of CAD who were operated on and discharged from the National Amosov Institute of Cardiovascular Surgery of the National Academy of Medical Sciences of Ukraine. The mean age of the patients was 61.9 ± 9.6 years. All the patients underwent laboratory examinations, electrocardiography, echocardiography, coronary angiography and cardiac surgery. The patients with uncomplicated forms of CAD (n = 194) underwent isolated surgical revascularization of the myocardium, in the case of complicated forms of CAD (n = 160), coronary bypass surgery was supplemented with valvular or ventricular correction. Results. Postoperative atrial fibrillation (AF) occurred in 40 (20.6%) patients with uncomplicated CAD and 43 patients with complicated CAD (26.8%), p = 0.1667. Among patients with complicated forms of CAD, 2 (1.25%) had paroxysms of ventricular tachycardia, which required the implantation of a cardioverter-defibrillator, also in this group of patients complete left bundle branch block occurred more often (p = 0.0020). The postoperative period in patients with impaired glucose metabolism was characterized by more frequent development of AF in patients with type 2 diabetes mellitus (33.3%, p = 0.0006), with impaired glucose tolerance (24.8%, p = 0.0156) compared to patients with normoglycemia (12.6%). Conclusions. There was no statistically significant difference in the frequency of postoperative AF in patients with various forms of CAD (p = 0.1667). In the occurrence of postoperative AF paroxysms, the negative influence of type 2 diabetes mellitus (p = 0.0006), impaired glucose tolerance (p = 0.0156), stage III-IV chronic kidney disease (p = 0.0015) and gouty arthritis (p = 0.0072) has been proven. The presence of postoperative AF was associated with acute encephalopathy (p = 0.0291) and panic attacks (p = 0.0043). The occurrence of postoperative AF increased the length of stay of cardiac surgery patients with CAD in the hospital from 8.2 ± 2.9 to 11.06 ± 6.8 days (p &lt; 0.0001).

Incidence and risk factors associated with atrioventricular block in the general population: the atherosclerosis risk in communities study and Cardiovascular Health Study

ObjectivesTo identify risk factors correlated with atrioventricular block (AVB) in the general population.MethodsParticipants in the Atherosclerosis Risk in Communities study (ARIC) and the Cardiovascular Health study (CHS) were enrolled. The presence of AVB was confirmed at an electrocardiogram (ECG) reading center using Minnesota ECG Classification. Cox proportional hazards models were performed to investigate potential risk factors of AVB, after adjustment for age, sex, race and traditional cardiovascular risk factors.ResultsDuring the 17 years of follow-up, a total of 731 high-degree AVB cases were identified. Age and sex-standardized rate of AVB was 2.79 and 2.35 per 1000 person-years in the white and the black population, respectively. With the increase of the geriatric population, the incidence of high-degree AVB will increase from 378,816 in 2020 to 535,076 in 2060, and most increment would occur among the elderly. Older age, male sex, the white race, overweight, comorbidities, declined forced vital capacity (FVC), elevated inflammation biomarkers, left bundle branch block and bifascicular block were independently associated with the incidence of high-degree AVB.ConclusionTo conclude, older age, male sex, white population, overweight, combined diabetes or chronic kidney disease, impaired FVC, elevated inflammation biomarkers, left bundle branch block and bifascicular block were independent predictors for high-degree AVB. The next 40 years would witness a dramatic increase in the incidence of high-degree AVB.

Comparison of the quality of logistic regression models and a classification tree in predicting hospital mortality in elderly patients with non-ST-elevation myocardial infarction

Aim. Using the CHAID (Chi Squared Automatic Interaction Detection) method to develop a classification tree for predicting hospital mortality in patients with non-ST-elevation myocardial infarction (non-STEMI) aged 75 years and older and compare the quality of the constructed model with the logistic regression model.Material and methods. A retrospective analysis of the case histories of 119 sequentially enrolled patients aged ≥75 years who were hospitalized in a cardiology department due to non-STEMI in 2020-2021 was carried out. The construction of a predictive model of probability of dying was carried out using the logistic regression method. To assess the impact of various predictors affecting the probability of dying during the of hospitalization period in patients with non-STEMI, a classification tree was developed using the CHAID method. To compare the quality of logistic regression models and the classification tree, the areas under the ROC curve and confidence intervals were estimated.Results. Based on the construction of a binary logistic regression, it was found that the factors increasing hospital mortality were cardiogenic shock (CS): odds ratio (OR) 47.55; 4.00-589.16; p=0.002; new-onset atrial fibrillation: OR 6.45; 1.39-30.42; p=0.018; and the number of points on the GRACE scale: for each increase by 1 point: OR 1.03; 1,00-1,05; p=0.046. Similar data were obtained when analyzing the classification tree: in patients with CS, the predicted mortality was 91.7%. The probability of an unfavorable outcome based on the constructed classification tree was higher than the average in the analyzed sample in persons without CS, 2-3 degree atrioventricular blocks, and pulmonary edema, but with right bundle branch block on the electrocardiogram (25.0%) and in persons without CS and atrioventricular blockages of 2-3 degrees, but with pulmonary edema and a Q wave on the electrocardiogram (50.0%). Both methods of predicting hospital mortality are applicable. There were no statistically significant differences in the quality of both constructed models; the difference in the areas under the ROC curves was 0.043±0.268 with a 95% confidence interval of -0.055-0.141, p=0.387.Conclusion. Both developed methods can be used to determine the probability of dying in a hospital. Currently, the recruitment of patients into a prospective study of a similar design has begun and is continuing, during which validation of the constructed forecasting models is planned.

Cardiac resynchronization therapy in heart failure based on Strauss criteria for left bundle branch block

Cardiac resynchronization therapy in heart failure based on Strauss criteria for left bundle branch block

Permanent left bundle branch area pacing improves mitral regurgitation and cardiac function in patients with right bundle branch block

BackgroundPermanent left bundle branch area pacing (LBBAP) has been established as an effective means to correct left bundle branch block. Right bundle branch block (RBBB), emerge as a distinct form of cardiac conduction abnormality, can be seen in the context of LBBAP procedure. However, the correction potential of LBBAP in patients with RBBB remains largely unexplored.ObjectiveThe objective of this study was to evaluate the efficacy and safety of permanent LBBAP in patients with RBBB.MethodsNinety-two consecutive patients who underwent successful permanent LBBAP were recruited from May. 2019 to Dec. 2022 in Fuwai Central China Cardiovascular Hospital. Among them, 20 patients with RBBB were included in our analysis. These patients were followed up at 1, 3, 6 and 12 months post-LBBAP. The QRS duration (QRSd) on the V1 lead of the 12-lead elctrocardiogram was measured and compared before and after the LBBAP procedure. Additionally, mitral regurgitation, tricuspid regurgitation and cardiac function were assessed using transthoracic echocardiography, specifically focusing on left ventricular ejection fraction (LVEF) and mitral regurgitation severity. The acute pitfills and delayed complications associated with the LBBAP procedure were recorded to evaluate its safety. SPSS 23.0 was used to perform statistical analysis with Student’s t test or one way ANOVA or nonparametric tests (paired Wilcoxon test). A p value less than 0.05 was defined as significant.ResultsThe demographic breakdown of the RBBB cohort revealed a mean age of 66.35 ± 11.55 years, 60% being male. Comorbidities were prevalent, including severe atrioventricular block (AVB) in 75%, sick sinus syndrome (SSS) in 20%, heart failure in 25%, atrial fibrillation in 30%, coronary heart diseases in 45%, hypertension in 35%, and diabetes mellitus in 15%. Regarding the LBBAP procedure, the average operation time was 106.53 ± 2.72 min, with 45% of patients (9 individuals) requiring temporary cardiac pacing during the surgery. Notably, the LBBAP procedure significantly narrow the QRS duration in RBBB patients, from 132.60 ± 31.49ms to 119.55 ± 18.58 ms (P = 0.046). Additionally, at the 12-month follow-up, we observed a marked improvement in LVEF, which increased significantly from 55.15 ± 10.84% to 58.5 ± 10.55% (P = 0.018). Furthermore, mitral regurgitation severity improved, with a median reduction from 4.46 (0.9, 7.3) to 2.29 (0, 3.49) cm2 (P = 0.033). Importantly, no cases of ventricular septum perforation or pericardial effusion were reported during the LBBAP procedure or during the follow-up period.ConclusionLBBAP provides an immediate reduction in QRS duration for patients suffering from RBBB, accompanied by improvements in mitral regurgitation and cardiac function as evident in the 12-month follow-up period.

Prognosis and predictors of right ventricular dysfunction by quantitative cardiac magnetic resonance in non-ischaemic cardiomyopathy.

Pathophysiology and prognostic implications of right ventricle (RV) dysfunction in heart failure are complex and incompletely elucidated. Cardiac magnetic resonance imaging (CMR) is the reference standard for RV quantification, but its clinical implications in non-ischaemic cardiomyopathy (NICM), in the context of myocardial fibrosis and functional mitral regurgitation are not well defined. We evaluated predictors, prognostic impact, and thresholds for defining significant RV dysfunction in NICM. NICM patients (n = 624) undergoing CMR assessment during 2002-2017 were retrospectively studied. CMR's quantification of right ventricular ejection fraction (RVEF) was evaluated against the primary outcome of all-cause mortality, heart transplant, and/or left ventricular assist device implantation in threshold and multivariable analyses. Mean RVEF was 43 ± 13%, and factors associated with reduced RVEF were male sex, New York Heart Association (NYHA) class III-IV, right bundle branch block, lower left ventricular ejection fraction, higher mitral regurgitant fraction (MR-RF) and right ventricle size in NICM. RVEF per 5% increase was independently associated with the primary endpoint hazards ratio (95% confidence interval) 0.80 (0.73-0.88), P < 0.001. RVEF ≤40% was the optimal threshold associated with worse prognosis, regardless of late gadolinium enhancement (LGE) or MR-RF quantification. On the other hand, higher LGE was associated with primary endpoint in patients with RVEF ≤40% only, while risk associated with MR-RF was significant dampened after adjusting for RVEF. RVEF provides powerful risk stratification, with RVEF ≤40% defining significant RV dysfunction associated with adverse outcomes in NICM. The integration of quantitative CMR measurements for RVEF, LGE, and MR-RF provides comprehensive NICM risk prognostication.

Impact of Newly Diagnosed Left Bundle Branch Block on Long-Term Outcomes in Patients with STEMI.

Background/Objectives: This study assessed the long-term prognostic implications of newly developed left bundle branch block (LBBB) in patients with ST-elevation myocardial infarction (STEMI) and a single coronary lesion, following primary percutaneous coronary intervention (PCI). Methods: Among 3526 patients admitted with acute myocardial infarction between January 2011 and December 2013, 42 were identified with STEMI, a single coronary lesion, and newly diagnosed LBBB. A control group of 42 randomly selected STEMI patients without LBBB was also included. All participants were prospectively evaluated with a median follow-up duration of 9.4 years. Demographic, clinical, and laboratory data were analyzed to assess the impact of LBBB on long-term outcomes. Results: The baseline characteristics were similar between the groups. The STEMI with new LBBB group had significantly higher rates of new myocardial infarction, revascularization, and mortality, highlighting the severe prognostic implications and elevated risk for adverse outcomes compared to STEMI without LBBB. The multivariate Cox regression analysis demonstrated that the presence of LBBB (HR: 2.15, 95% CI: 1.28-3.62, p = 0.003), lower LVEF (HR: 1.45, 95% CI: 1.22-1.72, p < 0.001), and longer pain-to-admission time (HR: 1.32, 95% CI: 1.09-1.61, p = 0.008) were significant independent predictors of adverse outcomes. Conclusions: Newly acquired LBBB in STEMI patients is associated with poorer long-term outcomes. Early identification and management of factors such as reduced LVEF and timely hospital admission, specifically in patients with new-onset LBBB, can improve prognosis.

A new electrocardiographic parameter terminal D1S + D3R predicts right ventricular dilatation in acute pulmonary embolism

Objective Right ventricular (RV) overload findings affect the risk classification and treatment approach in acute pulmonary embolism (APE). Recently, it was reported that a new electrocardiography (ECG) parameter, terminal D1S + D3R (T-D1S + D3R) pattern, supported the diagnosis of APE. We aim to search the relationship between T-D1S + D3R pattern and right ventricular dilatation (RVD) in APE. Methods This single-centre, retrospective study was designed with patients aged > 18 years. We screened 267 patients who underwent transthoracic echocardiography (TTE) because of confirmed APE in our emergency department. This study included 72 patients with RVD and 139 patients without RVD [male 41.7%, median age 73,0 (20.8) years; 49.6% male, median age 64,0 (24.0) years]. We compared T-D1S + D3R between RVD (+) and RVD (-) groups. Results We determined that RVD (+) group had more patients with the T-D1S + D3R parameter than RVD (-) group [51 (70.8%) vs. 25 (18.0%), p < 0.001]. In the univariate logistic regression analyses S1Q3T3, (in)complete right bundle branch block (RBBB), T-D1S + D3R, D3-V1 T wave inversion (TWI), V1-3/4 TWI, V1-3/4 ST-segment elevation, and frontal QRS-T [f(QRS-T)] angle predicted RVD, while T-D1S + D3R, V1-3/4 ST-segment elevation, and f(QRS-T) angle remained independent predictors of RVD in patients with APE. Conclusions T-D1S + D3R, a new ECG parameter, was an independent predictor of RVD in patients with APE.

A Study of Tpeak-Tend/QT Interval Ratio in Predicting Heart Failure in ST-Elevation Myocardial Infarction and Its Correlation With N-terminal Pro B-type Natriuretic Peptide (NT-proBNP).

Background Acute ST-elevation myocardial infarction (STEMI) is the most common cause of mortality across the world. The electrocardiogram (ECG) Tpeak-Tend/QT interval appears to be a measure of the left ventricle's transmural dispersion of repolarization (TDR). Prolongation of this time could indicate adverse cardiac events like heart failure, arrhythmias, etc. Heart failure is a clinical syndrome that includes signs and symptoms such as peripheral edema and high jugular vein pressure. N-terminal pro B-type natriuretic peptide (NT-proBNP) is an effective predictor of left ventricular function and also helps in predicting the disease prognosis. Elevated levels of NT-proBNP are seen in many cases of left ventricular dysfunction. This study aims to evaluate the predictive utility of the Tpeak-Tend/QT interval ratio in predicting major adverse cardiac events (MACEs), such as heart failure, by examining the Tend/QT interval ratio values with NT-proBNP in STEMI. Methodology This cross-sectional study was conducted at a tertiary hospital between April 2024 and June 2024. It included STEMI patients, excluding those with non-STEMI (NSTEMI), valvular heart diseases, bundle branch block, or pacemakers. The patients with a Tpeak-Tend/QT ratio < 0.3 were included in group A, and the Tpeak-Tend/QT ratio > 0.3 in group B. They were monitored for MACE-like heart failure during hospitalization and were compared with a study of the Tpeak-Tend/QT interval ratio in predicting heart failure in STEMI and its correlation with NT-proBNP levels. Results In this study, out of 45 patients, male predominance was observed, with 35 (78%) being men and 10 (22%) being women. In group A, the most common age group was 60-70 years, with 16 (51%) patients; in Group B, it was 50-60 years, with six (42.8%) patients. Out of 31 patients in group A, 25 were male, and six were female. In group B, out of 14 patients, 10 were male, and four were female. In this study, out of the 45 patients included, 12 (85%) among 14 patients who had MACEs like heart failure had a Tpeak-Tend/QT interval ratio of more than 0.3, and their measured NT-proBNP levels were also more than 900 pg/mL, thus showing a statistically significant association between Tpeak-Tend/QT interval ratio and NT-proBNP. Conclusion The present study showed an increased Tpeak-Tend/QT interval ratio and NT-proBNP in patients who developed heart failure in STEMI. As ECG is a readily available and affordable tool, the Tpeak-Tend/QT interval ratio can be used along with conventional markers like NT-proBNP to predict MACE in patients with STEMI.

Electrocardiographic Criteria for the Diagnosis of Acute Myocardial Infarction in Patients with Left Bundle Branch Block

During normal conduction system, the first segment depolarized is interventricular septum, normal ventricular depolarization begins with the septal fascicle of the left bundle branch followed by a simultaneous depolarization of the remaining ventricular walls from endocardium to pericardium via the right and left bundle branches. In left bundle branch block (LBBB) condition, the left ventricular activation is delayed, and the initial septal activation is from right to left, secondary ST segment and T wave abnormalities occur, and septal Q waves indicative of an MI are absent. About 0.5 percent of patients with acute myocardial infarction had left bundle-branch block Patients with left bundle branch block (LBBB) and suspected of acute myocardial infarction (MI) is challenge to the clinician. A diagnosis of MI with electrocardiogram (ECG) is especially difficult in the setting of LBBB because of the characteristic ECG changes caused by altered septal and left free wall ventricular depolarization. Here we review the pathophysiology of LBBB in MI, highlight evolving paradigms for the diagnosis of suspected MI in patients with LBBB.

Clinical analysis of maternal autoantibody-mediated complete left bundle branch block in 9 children

Objective: To analyze the clinical characteristics, treatment, and outcomes of children with complete left bundle branch block (CLBBB) mediated by maternal autoantibodies. Methods: A retrospective analysis was conducted on nine children diagnosed with maternal autoantibody-mediated CLBBB, treated at Beijing Anzhen Hospital and Fujian Provincial Hospital from March 2015 to August 2023. Their clinical characteristics, electrocardiographic and echocardiographic findings before and after treatment were reviewed. Paired sample t-test was used for inter-group comparison. Results: Among the mothers, 6 had positive antinuclear antibodies (ANA), 5 had anti-Sjogren syndrome antigen A antibodies, and 3 had anti-Ro-52 antibodies. The cohort included one female and eight male children, diagnosed with CLBBB at the age of 1 (2, 13) months. The positive autoantibodies in the infants, consisted with maternal antibodies, were detected within the first 3 months of life among 3 cases. Treatments included anti-heart failure therapy, myocardial nutritional support, intravenous immunoglobulin (IVIG) and glucocorticoids. Before treatment, the levels of troponin I (0.175 (0.060, 10.270) μg/L) and N-terminal pro-B-type natriuretic peptide (420 (327, 12 865) ng/L) were elevated, which normalized in most cases after treatment. Post-treatment, the QRS duration significantly shortened compared to pre-treatment ((137±15) vs.(169±25) ms, t=3.76, P<0.001), and the QTc interval significantly decreased ((433±41) vs. (514±27) ms, t=4.95, P=0.001). Before treatment, varying degrees of mitral and tricuspid regurgitation and marked interventricular septal dyskinesia were observed in echocardiography. After treatment, valve regurgitation and ventricular septum motion significantly improved, with a marked increase in left ventricular ejection fraction ((51±13)% vs. (27±6)%, t=-6.66, P<0.001). Conclusions: Maternal autoantibody-mediated CLBBB in children presents with chronic heart failure in infancy. Early treatment with anti-heart failure medications, IVIG and glucocorticoids can improve clinical symptoms.

Association of Electrocardiogram Findings With Clinical Outcomes in Patients With Chronic Coronary Syndrome: An Analysis of the ISCHEMIA Trials

ObjectiveWe aimed to investigate the association of electrocardiogram (ECG) findings with outcomes in patients with chronic coronary syndrome. MethodsThis secondary analysis of the ISCHEMIA and ISCHEMIA-CKD trials divided patients with chronic coronary syndrome into two groups, those with a normal ECG tracing and abnormal ECG tracing. Repolarization abnormalities included ST-segment depression ≥ 0.5 mm and T-wave inversion ≥ 1 mm; conduction abnormalities included left and right bundle branch block (LBBB and RBBB). The primary endpoint was cardiovascular death. Outcomes were assessed using a covariate-adjusted Cox-regression model. ResultsOf 5876 patients, 2901 (49.4%) had a normal and 2975 (50.6%) an abnormal ECG tracing. An abnormal ECG tracing at baseline, compared with a normal ECG tracing, was associated with an increased risk of cardiovascular death (257 of 2975 [8.6%] vs. 97 of 2901 [3.3%], adjusted hazard ratio [aHR] 2.01, 95% CI 1.58-2.55) over a median follow-up period of 3.1 years (IQR 2.1-4.2). This finding was consistent across subgroups except for patients with black skin color and current smokers, in whom an abnormal ECG was not significantly associated with increased risk of cardiovascular death. Individual ECG abnormalities (ST-segment depression [aHR 2.0, 95% CI 1.52-2.63], T-wave inversion [aHR 1.89, 95% CI 1.40-2.54], LBBB [aHR 1.74, 95% CI 1.05-2.90], and RBBB [aHR 1.52, 95% CI 1.04-2.22]) were independently associated with an increased risk of cardiovascular death. ConclusionIn patients with chronic coronary syndrome, an abnormal ECG tracing was associated with an increased risk of cardiovascular death. Our findings underscore the importance of the ECG in cardiovascular risk stratification and prognostication. Trial RegistrationNCT01471522, BioLINCC ID 14539.

A proposed algorithm for management of patients with left bundle branch block post-TAVR: 1-year follow-up

BackgroundTAVR has revolutionized the management of aortic stenosis and has become the standard of care across a broad spectrum of patients with aortic stenosis. However, it is still associated with high incidence of conduction abnormalities, particularly new LBBB. Management of these patients remains a challenge. ObjectiveTo assess the clinical outcomes of patients with post-TAVR conduction disorders managed according to a pre-specified institutionally developed algorithm. MethodsA retrospective analysis including all patients undergoing TAVR in our institute between October-2018 to December-2022 was performed. Patients with new LBBB were managed according to the algorithm comprising QRS width and electrophysiology study. In-hospital and one-year clinical outcomes were assessed. ResultsA total of 230 patients were included in the present analysis. Seventy patients (30.4%) developed new LBBB after TAVR. Overall, 44 patients (19.1%) required permanent pacemaker implantation (PPM): 20 patients (8.7%) with Mobitz II, complete AV block or alternating bundle branch block, 21 patients (9.1%) with persistent new LBBB, and 3 others (1.3%) per physician discretion. During 1-year follow-up, only 3 patients required late PPM, of whom only 1 patient with new LBBB. There was no difference in mortality or heart failure hospitalizations between the PPM and No PPM groups. Multivariable analysis identified atrial fibrillation, chronic kidney disease, and pre-TAVR RBBB as independent predictors for PPM following TAVR. ConclusionOur findings suggest that the presented algorithm may serve as a safe and efficacious strategy for management of patient with post-TAVR LBBB, although the PPM rate may be further reduced.

Association of QRS Duration with Echocardiographic Left Ventricular Dimensions

Background: QRS duration (QRSd) is used to diagnose left bundle branch block (LBBB) and is important for determining cardiac resynchronization therapy eligibility. Others have reported associations of left bundle branch block (LBBB) and interventricular conduction delay with left ventricular (LV) systolic and diastolic dysfunction in patients without clinical HF. Individualized QRSd thresholds may improve diagnosis and intervention strategies. The goal of this study was to assess the relations of QRS duration to echocardiographic left ventricular (LV) dimensions in individuals. Methods: This was a hospital-based cross-sectional analytical study. A total of 134 purposively selected respondents were included in the study from the patients attending the outpatient or inpatient department of cardiology, Dhaka Medical College Hospital, advised for an echocardiogram. They were divided into two groups depending on their QRS complex duration (Group I≤100 ms and Group II&gt;100 ms). After taking informed written consent, a case record form was filled and Echo measurements were taken following standard procedure with confidentiality. Results: Among the respondents, the mean age was found 52.68 ± 14.24 years. The majority were male (68%), and around 1/3rd of the respondents were overweight or obese. Males were found to have less QRS duration than females (p&lt;0.001) but there was no difference in age (p=0.814) between the groups. All the risk factors considering obesity, diabetes mellitus, hypertension, family history, smoking status, and dyslipidemia were found in similar proportions in both groups (p&gt;0.05). The study found that the interventricular septum thickness and inferolateral wall thickness were higher among those having a QRS duration of more than 100 ms (Group II), but this difference was not significant (p &gt; 0.05). On the other hand, left ventricular diastolic dimension, systolic dimension, and left ventricular mass were found to be increased significantly (p&lt;0.05) with a reduction in ejection fraction in Group II (p&lt;0.05). Conclusion: Left ventricular diastolic and systolic dimensions along with left ventricular mass significantly increase according to QRS duration among the patients. Meanwhile, a reduction in ejection fraction was also evident. (Bangladesh Heart Journal 2024; 39(2): 144-150

Acurate neo2 is associated with a reduced inflammatory response in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation.

Inflammation following transcatheter aortic valve implantation (TAVI) is associated with an increased risk of adverse outcomes. The aim of this study was to compare the inflammatory response between low radial force valves (Acurate neo2, Boston Scientific) and high radial force valves (Evolut R/Pro, Medtronic; SAPIEN Edwards Lifesciences; and Myval, Meril valves). We conducted a retrospective study of patients with severe aortic stenosis treated with TAVI between 2021 and 2022. The primary endpoint was the difference in the inflammatory response between low radial force valves and high radial force valves, measured as the difference between post-procedural and pre-procedural high-sensitivity C-reactive protein levels (hsCRP delta). A total of 114 patients were included, of which 65 patients (57%) received a low radial force valve. The hsCRP delta was lower in the low radial force valve group compared to the high radial force valve group (8.7 [2.1-15.6] mg/L vs. 18.8 mg/dL [6.4-19] mg/L; P=0.003), due to a lower post-implantation hsCRP (8.9 [5.45-19.6] mg/L vs. 15.8 [9.8-27.3] mg/L; P=0.013). The incidence of new left bundle branch block (LBBB) after TAVI was lower in the low radial force valve group compared to the high radial force valve group (11 [17%] vs. 18 [37%]; P=0.020). Low radial force TAVI prostheses were associated with a lower inflammatory response, and a lower incidence of new LBBB compared to the radial force valve group, suggesting that inflammation may contribute to the increased risk of conduction disturbances.