Complete Right Bundle Branch Block Research Articles

Prevalence and Clinical Significance of Intraventricular Conduction Disturbances in Hospitalized Children.

Introduction: Data on the prevalence and clinical significance of interventricular conduction disturbances (IVCDs) in children are scarce. While incomplete right bundle branch blocks (IRBBBs) seem to be the most frequent and benign findings, complete bundle blocks and fascicular blocks are often seen in children with congenital/acquired cardiac conditions. This study aims to delineate the prevalence and the diagnostic accuracy of IVCD in children admitted to a paediatric cardiology unit. Methods: Children admitted to the paediatric cardiology unit between January 2010 and December 2020 who had an ECG were included in the study. IVCDs were diagnosed according to standard criteria adjusted for age. Results: Three thousand nine hundred and ninety-three patients were enrolled. The median age was 3.1 years (IQR: 0.0-9.2 years), and 52.7% were males. IVCDs were present in 22.5% of the population: 17.4% of the population presented with IRBBBs, 4.8% with a complete right bundle branch block (CRBBB), 0.1% with a complete left bundle branch block (CLBBB), 0.2% with a left anterior fascicular block (LAFB) and 0.2% with a combination of CRBBB and LAFB. Also, 26% of children with congenital heart disease had an IVCD, and 18% of children with an IVCD had previous cardiac surgery. The overall sensitivity of IVCD in detecting a cardiac abnormality was 22.2%, with a specificity of 75.5%, a PPV of 83.1% and an NPV of 15.1%, but the values were higher for CLBBB and LAFB. Conclusions: IVCDs were present in one-fifth of children admitted to the cardiology unit. IRBBB was the most frequent disturbance, while CRBBB, CLBBB and fascicular blocks were much rarer, though they had a higher predictive value for cardiac abnormalities.

Transient complete right bundle branch block due to lung contusion: case report

Introduction: Right bundle branch block (RBBB) may occur in lung diseases and cardiovascular diseases. 
 Case Report: A 25-year-old male patient was admitted to emergency department after a motorcycle accident. Contusion was detected in bilateral lungs, and pneumothorax with laceration were detected in the right lung. ECG revealed 103 bpm, right axis deviation, and complete RBBB. ECG revealed 83 bpm, complete RBBB continued at the 6th hour after tube thoracostomy, and high sensitive TnI was normal. Chest X-ray was normal on the 4th day of hospitalization, and ECG revealed 74 bpm, normal sinus rhythm. 
 Conclusion: In thoracic trauma, ECG changes may develop as a result of lung contusion. ECG findings improve as the lung contusion heals.

Prevalence and Clinical Significance of Electrocardiographic Complete Right Bundle Branch Block in Young Individuals.

There is limited information on the clinical significance of complete right bundle branch block (CRBBB) in young individuals. The aim of this study was to determine the prevalence and significance of CRBBB in a large cohort of young individuals aged 14-35 years old. From 2008 to 2018, 104,369 consecutive individuals underwent a cardiovascular assessment with a health questionnaire, electrocardiogram, clinical consultation, and selective echocardiography. Follow-up was obtained via direct telephone consultations. Mean follow-up was 7.3 ± 2.7 years. CRBBB was identified in 154 (0.1%) individuals and was more prevalent in males compared with females (0.20% vs. 0.06%; p<0.05) and in athletes compared with non-athletes (0.25% vs. 0.14%; p<0.05). CRBBB-related cardiac conditions were identified in 7 (5%) individuals (4 with atrial septal defect, 1 with Brugada syndrome, 1 with progressive cardiac conduction disease and 1 with atrial fibrillation). Pathology was more frequently identified in individuals with non-isolated CRBBB compared with individuals with isolated CRBBB (14% vs 1%; p < 0.05) and in individuals with a QRS duration of ≥130 milliseconds (ms) compared with individuals with a QRS of <130ms (10% vs 1%; p<0.05). The prevalence of CRBBB in young individuals was 0.1% and was more prevalent in males and athletes. CRBBB-related conditions were identified in 5% of individuals and were more common in individuals with non-isolated CRBBB and more pronounced intraventricular conduction delay (QRS duration of ≥130ms). Secondary evaluation should be considered for young individuals with CRBBB with symptoms, concerning family history, additional electrocardiographic anomalies or significant QRS prolongation (≥130ms).

Electrocardiographic evolution in Anderson-Fabry disease: a valuable tool to detect progressive cardiac involvement

Abstract Background Anderson-Fabry disease (AFD) is a multisystemic disorder caused by accumulation of glycosphingolipid in affected tissues and cardiac involvement can manifest with left ventricular hypertrophy (LVH), conduction delays, arrythmias and valvulopathies. Electrocardiogram (ECG) has proven to be useful for early detection of this condition, but there are only few datas on the association between ECG alterations and the progression of the disease. Purpose To evaluate the association between ECG anomalies and progressive cardiac involvement in AFD patients with different degrees of left ventricular hypertrophy. Methods We recruited 189 AFD patients &amp;gt; 18 years old (39% males, median age 47 years, 68% classical AFD) in a multicentre cohort and we divided them into 4 groups according to different degree of left ventricular (LV) thickness: group A ≤ 9mm (n = 52, 28%); group B 10-14 mm (n = 76, 40%); group C 15-19 mm (n = 46, 24%); group D ≥ 20 mm (n = 15, 8%). They underwent a complete clinical, ECG and echocardiographic evaluation and we analysed their ECG features in order to detect patterns suggestive of the different stages of AFD. Results A normal ECG was present in 87% of patients in group A, 54% in group B, 11% in group C, and 7% in group D. The most common conduction delay type was right bundle branch block (RBBB), mainly incomplete in groups B and C (respectively 20% and 22%) and complete RBBB in group D (53%), with p &amp;lt; 0.001; whereas none of the patients had LBBB. The prevalence of LVH criteria showed a statistically significant increase among the groups (p &amp;lt; 0.001) and also negative T waves and ST segment depression were more frequent in group C and D (p &amp;lt; 0.001), involving mainly lateral and inferior leads. Analysing these results we proposed ECG patterns representative of different AFD stages characterized by increasing LV thickness. In patients with normal LV thickness (group A) we noticed a high prevalence of normal ECG (87%) and minor anomalies like LVH criteria/giant positive T waves (8%) and delta wave/slurred QRS onset together with borderline PR (8%). Differently patients with intermediate LV thickness (group B and C) show more heterogeneous ECG alterations: LVH/giant positive T waves (17% and 7%); LVH+LV strain (9% and 17%); incomplete RBBB associated with repolarization abnormalities (8% and 9%) which were more frequently associated with LVH criteria in group C than B (8% and 15% respectively). In patients with severe LVH (group D) we detected more significant anomalies, like complete RBBB associated to LVH and repolarization abnormalities (40%), sometimes with QRS fragmentation (13%). Conclusions ECG represents an important tool for early detection and long-term monitoring of cardiac involvement in AFD with particular ECG features that evolve together with the natural history of the disease and with the progression of the LVH. Their potential association with clinical events remains unknown.

Calcification of aortic valve cusps as independent predictor for permanent pacemaker requirement after transcatheter aortic valve implantation

Abstract Background High-degree atrioventricular (AV) block represents a frequent complication after transcatheter aortic valve implantation (TAVI). Extension of indication for TAVI towards subjects with lower surgical risk requires to reduce the likelihood for the need of permanent pacemaker (PPM) implantation. Purpose We examined the role of calcification of the aortic valve cusps and left ventricular outflow tract (LVOT) as potential predictors for PPM implantation after TAVI. Methods In a cohort of 1200 consecutive patients without PPM who underwent transfemoral TAVI, clinical and procedural characteristics as well as requirement for PPM implantation after TAVI were assessed systematically. In all patients, cardiac computed tomography (CT) was performed before TAVI including quantitative assessment of calcium volume of the aortic valve cusps and the LVOT in mm3 (see figure). Results Median patient age was 81 (IQR 7) years, 50% were male. 9.8% of patients had a pre-existing complete right bundle branch block (RBBB) in ECG. 68% of subjects received a balloon-expandable valve, 32% a self-expandable valve. Postinterventional PPM implantation was necessary in n=155 subjects (13%) due to high-degree AV block. In this group of subjects, calcification of the aortic valve cusps was more pronounced than in the group of subjects without high-degree AV block (see table). Univariate regression analysis revealed pre-existing complete RBBB (p&amp;lt;0.001, OR 8.564), implantation of a self-expandable prosthesis (p=0.013, OR 1.549) as well as calcification of the non-coronary (p=0.016, OR 1.001) and left-coronary cusp (p=0.025, OR 1.001) as significant predictors for PPM implantation. In multivariate regression analysis, these predictors – including calcification of the non-coronary cusp (p=0.037, OR 1.001) remained significant. With every mm3 of calcification, risk for high-degree AV block and PPM implantation increases by 0.1%. With a median calcification of 225 mm3 of the non-coronary cusp, this would make a 22.5% relative risk increase. Conclusion In a large cohort of 1200 patients, the volume of aortic cusp calcification, in particular calcification of the non-coronary cusp, was identified as independent predictor for PPM implantation following transcatheter aortic valve implantation. This might be explained by the anatomical proximity of both the AV node and left Tawara branch to the non-coronary cusp, resulting in a higher risk of compression during valve implantation. Our results may contribute to improved risk stratification regarding the need for PPM implantation after TAVI.Assessment of calcium volumeComparison of calcification

Abstract 18352: Impact of Approach Site on Conduction Defect in Right Ventricular Biopsy

Introduction: Myocardial biopsy is a fundamental procedure for diagnosing myocarditis and cardiomyopathy. Complete right bundle branch block (CRBBB) is a potential complication of right ventricular biopsy (RV-EMB) that occurs at a certain rate. Consequently, patients with complete left bundle branch block (CLBBB) often exhibit reluctance to undergo RV-EMB due to the risk of complete atrioventricular block. However, it is precisely in such cases that the diagnosis of CLBBB through myocardial biopsy becomes crucial and concerns clinicians.Although there are two approaches to RV-EMB, namely the transfemoral vein and transjuglar vein approaches, and each institution has its preferred method, no study has investigated the variation in complication rates, particularly the occurrence of CRBBB, based on the different approach sites for RV-EMB. AIMS:This study aims to analyze the disparity in complication rates, primarily CRBBB, attributable to differences in the approach site during the RV-EMB procedure. METHODS/RESULTS: Over all 266 cases who underwent RV-EMB at Kanazawa University between January 2017 and December 2022 including 87 cases with transfemoral venous approach (Group TF) and 179 cases with transjugular venous approach (Group TJ) were enrolled in this retrospective single-center study. Group TF exhibited a higher usage of warfarin (15.1% vs. 3.4%, p=0.001) and obtained fewer specimens compared to Group TJ (2.97±0.98 vs. 3.90±0.65 pieces, p&lt;0.001).Transient CRBBB was observed in 26 (29.9%) patients in Group TF and 13 (7.3%) patients in Group TJ (p&lt;0.001); CRBBB persisted beyond 24 hours in 8 (9.1%) and 2 (1.1%) patients(p=0.004), respectively. One case of cardiac tamponade occurred in Group TF, and two cases of VF were reported in Group TJ, with no instances of stroke, permanent pacemaker implantation, or mortality.Multivariate logistic regression analysis identified approach cite (Group TF/TJ) as an independent predictor of CRBBB (p&lt;0.001, odds ratio 0.43). CONCLUSIONS: The transjugular venous approach in RV-EMB demonstrates potential in reducing the occurrence of CRBBB as a complication. In cases where complete atrioventricular block is a concern, such as those with CLBBB, the transjugular vein approach may be preferable.

Electrocardiogram analysis in Anderson-Fabry disease: a valuable tool for progressive phenotypic expression tracking.

Electrocardiogram (ECG) has proven to be useful for early detection of cardiac involvement in Anderson-Fabry disease (AFD); however, little evidence is available on the association between ECG alterations and the progression of the disease. To perform a cross sectional comparison of ECG abnormalities throughout different left ventricular hypertrophy (LVH) severity subgroups, providing ECG patterns specific of the progressive AFD stages. 189 AFD patients from a multicenter cohort underwent comprehensive ECG analysis, echocardiography, and clinical evaluation. The study cohort (39% males, median age 47 years, 68% classical AFD) was divided into 4 groups according to different degree of left ventricular (LV) thickness: group A ≤ 9 mm (n = 52, 28%); group B 10-14 mm (n = 76, 40%); group C 15-19 mm (n = 46, 24%); group D ≥ 20 mm (n = 15, 8%). The most frequent conduction delay was right bundle branch block (RBBB), incomplete in groups B and C (20%,22%) and complete RBBB in group D (54%, p < 0.001); none of the patients had left bundle branch block (LBBB). Left anterior fascicular block, LVH criteria, negative T waves, ST depression were more common in the advanced stages of the disease (p < 0.001). Summarizing our results, we suggested ECG patterns representative of the different AFD stages as assessed by the increases in LV thickness over time (Central Figure). Patients from group A showed mostly a normal ECG (77%) or minor anomalies like LVH criteria (8%) and delta wave/slurred QR onset + borderline PR (8%). Differently, patients from groups B and C exhibited more heterogeneous ECG patterns: LVH (17%; 7% respectively); LVH + LV strain (9%; 17%); incomplete RBBB + repolarization abnormalities (8%; 9%), more frequently associated with LVH criteria in group C than B (8%; 15%). Finally, patients from group D showed very peculiar ECG patterns, represented by complete RBBB + LVH and repolarization abnormalities (40%), sometimes associated with QRS fragmentation (13%). ECG is a sensitive tool for early identification and long-term monitoring of cardiac involvement in patients with AFD, providing "instantaneous pictures" along the natural history of AFD. Whether ECG changes may be associated with clinical events remains to be determined.

Significant Delayed Activation on the Right Ventricular Outflow Tract Represents Complete Right Bundle-Branch Block Pattern in Brugada Syndrome.

Background The appearance of complete right bundle-branch block (CRBBB) in Brugada syndrome (BrS) is associated with an increased risk of ventricular fibrillation. The pathophysiological mechanism of CRBBB in patients with BrS has not been well established. We aimed to clarify the significance of a conduction delay zone associated with arrhythmias on CRBBB using body surface mapping in patients with BrS. Methods and Results Body surface mapping was recorded in 11 patients with BrS and 8 control patients both with CRBBB. CRBBB in control patients was transiently exhibited by unintentional catheter manipulation (proximal RBBB). Ventricular activation time maps were constructed for both of the groups. We divided the anterior chest into 4 areas (inferolateral right ventricle [RV], RV outflow tract [RVOT], intraventricular septum, and left ventricle) and compared activation patterns between the 2 groups. Excitation propagated to the RV from the left ventricle through the intraventricular septum with activation delay in the entire RV in the control group (proximal RBBB pattern). In 7 patients with BrS, excitation propagated from the inferolateral RV to the RVOT with significant regional activation delay. The remaining 4 patients with BrS showed a proximal RBBB pattern with the RVOT activation delay. The ventricular activation time in the inferolateral RV was significantly shorter in patients with BrS without a proximal RBBB pattern than in control patients. Conclusions The CRBBB morphology in patients with BrS consisted of 2 mechanisms: (1) significantly delayed conduction in the RVOT and (2) proximal RBBB with RVOT conduction delay. Significant RVOT conduction delay without proximal RBBB resulted in CRBBB morphology in patients with BrS.

PO-04-201 A CASE OF PVC OCCURRING RIGHT BUNDLE BRANCH BLOCK AND PR INTERVAL PROLONGED DURING ETHANOL ABLATION VIA THE CORONARY VENOUS SYSTEM

Ethanol ablation via the coronary venous system (CVS) has been reported to be effective and safe as a novel therapy for ventricular arrhythmias, especially for the epicardial and intramural origin sites. Previous studies reported no heart block complications during retrograde coronary venous ethanol ablation, neither atrioventricular block (AVB) nor other types of conductive system block. N/A A 67-year-old female with symptomatic and drug-refractory premature ventricular contractions (PVCs) was admitted for ablation therapy. The PVC burden was 31.7%. The 12-lead ECG showed a PVC with LBBB, inferior axis with a precordial transition in lead V3, and QS pattern in lead I. The QRS duration of PVC was 143ms. The Q-wave ratio of lead aVL/aVR was 1.47. Endocardial mapping was performed using a 3.5mm open-irrigated-tip catheter (ThermoCool, Biosense Webster, CA, USA). The earliest activation time was -8ms and -10ms pre-QRS at the septal aspect of right ventricular outflow tract (RVOT) and the left coronary sinus (LCC), respectively (Fig 1A). Ablation with 35-40W, 45-50°C was attempted but no response. We considered it might be an intramural origin site. The CVS angiography was performed and the ablation catheter was positioned in LCC for reference (Fig 1B). The earliest activation time (-27ms) was mapped in a septal branch of the anterior interventricular vein (AIV) with a 3.3F quadripolar catheter and local pace mapping matched well. Selective angiography confirmed the quadripolar catheter was in the septal branch rather than AIV (Fig 1C-D). A balloon was used to deliver ethanal and prevent its backflow to AIV. 1ml 96% ethanol was infused slowly (Fig 1E-F). PVC was eliminated immediately as soon as the ethanol infusion. But we noticed the PR interval prolonged from 178 to 190ms. More ethanol was injected carefully to consolidate the effect but we stopped infusion after a total of 2.5ml ethanol because the ECG showed complete RBBB and PR interval prolonged further to 202ms. RBBB and I° AVB were persistent during the whole hospitalization for 3 days. However, at 1-month follow-up, the QRS morphology returned to normal and the PR interval shortened to 172ms (Fig 1G). 24-hour Holter showed no recurrence. Ethanol ablation via the CVS also might induce heart block complications due to the adjacent anatomical position with the conductive system, even though it might be reversible. Operators should be cognizant of the potential risk.

Right bundle branch block evolving to myocardial ischemia in a patient with chronic middle back pain: a case report

BackgroundA right bundle branch block (RBBB) is rarely found in patients with myocardial infarction (MI). In addition, back pain is an atypical complaint in patients with angina.CaseA 77-year-old Javanese male was admitted with middle back pain that he had had for several months but that had become worse in the past week. He received an oral nonsteroidal anti-inflammatory drug as analgesic therapy but the pain did not improve. The patient came to the emergency room and an electrocardiogram (ECG) showed complete RBBB and first-degree atrioventricular block. Three days after hospital admission, his chief complaint of pain had worsened, and ECG showed new deep arrow-head inverted wave at V3–V6, II, III, and aVF, as well as infero-anterolateral ischemia. The coronary angiography revealed 95% critical stenosis in left circumflex artery.DiscussionIt is a challenge for clinicians to recognize and carefully assess a patient’s complaints even if they are admitted for pain that is “atypical” of MI. When ECG shows changes, clinicians need to pay attention to a tricky, hidden, and life-threatening occlusion of the coronary artery.

Left Ventricular "Longitudinal Rotation" and Conduction Abnormalities-A New Outlook on Dyssynchrony.

The complete left bundle branch block (CLBBB) results in ventricular dyssynchrony and a reduction in systolic and diastolic efficiency. We noticed a distinct clockwise rotation of the left ventricle (LV) in patients with CLBBB ("longitudinal rotation"). The aim of this study was to quantify the "longitudinal rotation" of the LV in patients with CLBBB in comparison to patients with normal conduction or complete right bundle branch block (CRBBB). Sixty consecutive patients with normal QRS, CRBBB, or CLBBB were included. Stored raw data DICOM 2D apical-4 chambers view images cine clips were analyzed using EchoPac plugin version 203 (GE Vingmed Ultrasound AS, Horten, Norway). In EchoPac-Q-Analysis, 2D strain application was selected. Instead of apical view algorithms, the SAX-MV (short axis-mitral valve level) algorithm was selected for analysis. A closed loop endocardial contour was drawn to initiate the analysis. The "posterior" segment (representing the mitral valve) was excluded before finalizing the analysis. Longitudinal rotation direction, peak angle, and time-to-peak rotation were recorded. All patients with CLBBB (n = 21) had clockwise longitudinal rotation with mean four chamber peak rotation angle of -3.9 ± 2.4°. This rotation is significantly larger than in patients with normal QRS (-1.4 ± 3°, p = 0.005) and CRBBB (0.1 ± 2.2°, p = 0.00001). Clockwise rotation was found to be correlated to QRS duration in patients with the non-RBBB pattern. The angle of rotation was not associated with a lower ejection fraction or the presence of regional wall abnormalities. Significant clockwise longitudinal rotation was found in CLBBB patients compared to normal QRS or CRBBB patients using speckle-tracking echocardiography.

486 ELECTROCARDIOGRAPHIC EVOLUTION IN ANDERSON-FABRY PATIENTS ON DISEASE SPECIFIC THERAPY

Abstract Background Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder that have gained attention due to the availability of therapeutic options. Disease specific therapy (DST), either by enzyme replacement therapy or oral pharmacological chaperone, is the mainstay for AFD treatment. Although its widespread use, few data are available on the electrocardiographic variations associated with DST. Purpose To evaluate ECG findings and variations in AFD according to time duration of DST, comparing patients under long-term therapy with naïve patients starting therapy during follow-up. Methods One-hundred-seventy-nine AFD patients, ≥18 years old, with 2 readable ECGs, were recruited in the present multicentre study cohort. Two patients were excluded due to pacemaker (PM) implantation. Only patients on DST (n=107) were considered for final cohort and divided into 2 groups according to therapy duration: Group A (n=42) included patients treated for ≥12 months at the time of first evaluation, whereas Group B patients (n=65) started therapy during follow-up. Results Group A and Group B had not significant difference in terms of age at presentation (48[39-60] vs 48[36-56]years; p=0.856) and maximal wall thickness (13[11-15] vs 13[11-18]mm; p=0.090) whereas they differed for male prevalence (61% vs 38%; p=0.029) and classic phenotype (86% vs 29%; p&amp;lt;0.0001). At baseline, more than half of both groups had ECG abnormalities (61% vs 61%; p=1.000). The prevalence among Group A and Group B of atrial fibrillation (AF 5% vs 6%; p=1.000), first degree atrioventricular block (AVB, 7% vs 5%; p=0.677), right bundle branch block (RBBB, complete 7% vs 8%; p=1.000; incomplete RBBB 14% vs 12%; p=0.776), left anterior fascicular block (LAFB, 10% vs 9%;p=1.000) and repolarization abnormalities (48% vs 38%; p=0.423) was not significantly different. Conversely, left ventricular hypertrophy (LVH) was more prevalent in Group A (64% vs 37%; p=0.010). During the follow-up (57[60-28] months for Group A vs 70[37-85] months for Group B; p=0.152), both groups developed electrocardiographic alterations (38% vs 23%; p=0.127). Specifically, in GroupA, 4 (10%) patients presented AF, 1 (2%) AVB, 7 (17%) complete or incomplete RBBB, 4 (10%) LAFB, 1 (2%) LVH and 8 (19%) repolarization abnormalities. In Group B, 2 (3%) developed AF, 1 (2%) AVB, 7 (11%) complete or incomplete RBBB, 2(3%) LVH and 11(17%) repolarization abnormalities; none developed LAFB. Conclusions In this AFD cohort, both patients on chronic DST (Group A) and patients who started treatment during follow-up (Group B) developed ECG alterations. Treatment status didn't affect considerably the developing of ECG abnormalities and DST did not prevent ECG changes. ECG alterations during the follow-up were more frequent in Group A (38% vs 23%), mainly composed by classic phenotype and male patients, thus supporting a prompt start of therapy at an early stage.

Electrocardiographic phenotype of exercise-induced arrhythmogenic cardiomyopathy: A retrospective observational study.

The right ventricle can be susceptible to pathologic alterations with exercise. This can cause changes to the ECG. Our aim was to identify the electrocardiographic phenotype of exercise induced (ExI) arrhythmogenic cardiomyopathy (ACM). A retrospective analysis of ECGs at rest, peak exercise and 1 min of recovery in four groups of individuals was performed: Arrhythmogenic Cardiomyopathy with genetic confirmation (Gen-ACM; n = 16), (genetically negative) ExI-ACM (n = 15), control endurance athletes (End; n = 16) and sedentary individuals (Sed; n = 16). The occurrence of ventricular arrhythmias (VA) and, at each stage, QRS duration, Terminal Activation Delay (TAD), the ratio of the sum of the QRS durations in the right precordials (V1-V3) over that in the left precordials (V4-V6; R/L duration ratio), the presence of complete RBBB and T-wave inversion (TWI) beyond lead V2 were evaluated. At rest, complete RBBB was exclusively found in Gen-ACM (6%) and ExI-ACM (13%). No epsilon waves were identified. TWI beyond V2 was uniquely present in Gen-ACM (73%) and ExI-ACM (38%; p < 0.001). VA was present in Gen-ACM (88%); ExI-ACM (80%), End (25%) and Sed (19%; p < 0.001). The presence of R/L duration ratio of >1.2 and TAD ≥ 55 ms were not significantly different over the four groups (p = 0.584 and p = 0.218, respectively). At peak exercise the most striking finding was a significant decrease of the R/L duration ratio in individuals with ACM, which was the result of lateral precordial QRS prolongation. ExI-ACM shares important ECG-features with Gen-ACM, suggesting a similar underlying pathogenesis regardless of the presence or absence of desmosomal mutations.

A 28-Year-Old Male Patient With Right Heart Failure Due To Pulmonary Hypertension

Abstract Right Heart Failure (RHF) as a rapidly progressive syndrome with systemic congestion in the setting of impaired RV filling and/or decreased RV outflow output. A 28-year-old male patient, a photographer, lived in North Aceh was admitted to the ED of Cut Meutia Hospital. He was admitted with worsening dyspnea since 2 days before, initiated after a periode of fever. He also complained of fatigue, palpitations in ordinary activities and chest pain occasionally. He had history of presyncope and syncope. He denied any history of hypertension, type 2 diabetes, allergies, and active smoking. He had no congenital or family history of heart disease. Physical examination revealed full of conciousness with slightly abnormal vital sign. He had malar rash, dilated jugular vein. The apex of the heart shifts to the axilla anterior line, S1&gt;S2 with systolic murmur (+). ECG showed complete RBBB with RAD and chest x-ray showed cardiomegaly. The transthoracic echocardiogram revealed severe TR (Tricuspid Regurgitation), dilatation of RARV (Right Atrium Right Ventricle), with severe PH (Pulmonary Hypertension). The patient was diagnosed with RHF (Right Heart Failure) caused by primary PH. The patient was placed on intravenous furosemide, spironolacton, digoxin, and sildenafil. Treatment and lifestyle modification were expected to improve the quality of life.

Reversible T-wave inversions during left bundle branch area pacing.

Our clinical observation found that T-wave inversions (TWIs) appeared during left bundle branch area pacing (LBBAP); however, the incidence and influencing factors were unclear. The study aimed to investigate the effects of LBBAP on T-wave and explore possible factors associated with TWIs. This was a retrospective cohort study. An electrocardiogram (ECG) was acquired at baseline and after LBBAP. Baseline characteristics, ECG parameters, LBBAP parameters, and troponin T (TnT) levels were compared between the non-TWIs and TWIs groups. Multivariable logistic analyses were performed to adjust for potential confounders to identify the predictive factors of TWIs during LBBAP. A total of 398 consecutive patients who underwent successful LBBAP were assessed for inclusion between May 2017 and Jan 2021, and 264 (66.3%) patients had TWIs. The mean (standard deviation [SD]) baseline QRS duration (QRSd) was longer in the TWIs group compared to the non-TWIs group (125.9 [34.5] ms vs. 98.2 [18.1] ms; P <0.001). Multivariable logistic regression analysis suggested that QRSd >120 ms was an independent predictor for TWIs. TWIs were partially or com-pletely recovered in 151/172 (87.8%) patients during follow-up, the median (interquartile range [IQR]) follow-up duration was 10 days (7 days to 5.5 months). TWIs in patients with complete left bundle branch block (CLBBB) occurred more frequently in inferior wall leads (II, III, and aVF) and anterior wall leads (V1-V4) (P <0.05). Patients with complete right bundle branch block (CRBBB) were more prone to TWIs in high lateral wall leads (I and aVL) (P <0.05). There were no significant differences in TnT levels between the TWIs and non-TWIs groups. TWIs during LBBAP were clinically frequent and recoverable. QRSd >120 ms was independently associated with TWIs.

ECG as a storytelling of cardiac involvement evolution in Anderson Fabry disease

Abstract Background Cardiac involvement in Anderson-Fabry disease (AFD) is related to a progressive glycosphingolipid storage over time and is characterized by left ventricular hypertrophy (LVH), conduction abnormalities and myocardial fibrosis. ECG is useful for early recognition of AFD, however evidence is limited on the association between ECG alterations and disease stage. Purpose To assess the relationship between ECG characteristics and progressive cardiac involvement, from the pre-hypertrophic phase to phenotypes with increasing degree of LVH. Methods In a multicenter cohort, 183 AFD patients (40% male, age 47±12 years, 60% affected by “classical AFD”) underwent ECG and transthoracic echocardiography. Patients were divided into 4 groups according to the different degree of LV thickness measured in parasternal short axis view: group A ≤9 mm (N=46, 25%), group B 10–14 mm (N=77, 42%), group C 15–19 mm (N=45, 25%) and group D ≥20 mm (N=15, 8%). Patients with pacemaker and under 18 years of age were excluded. Results A normal ECG was present in 89% in group A, 59% in group B, 11% in group C and it was absent in group D. Short PR (&amp;lt;120 ms) was more frequent in group A, whereas with LVH increasing, median PR interval duration significantly prolonged among the 4 groups (136 [125–150]vs 141 [130–160] vs 160 [130–180] vs 170 [130–180] ms, p=0.002 respectively). Median P-wave duration was shorter in group A and B compared to group C and D (80 m vs 100 ms, p&amp;lt;0.001), while both QRS and QTc gradually increased. Median Sokolow-Lyon voltage criteria statistically augmented among the groups (22 [18–26] vs 27 [20–33] vs 32 [25–45] vs 35 [18–40] mm, p&amp;lt;0.001 respectively), along with right ventricular hypertrophy (0%, 1%, 11%, 8%, p=0.02). Right bundle branch block (RBBB) had a higher frequency in advanced stages (0%, 34%, 34%, 40%, p&amp;lt;0.001), with a prevalence of complete RBBB of 46% in group D. Similarly, left anterior fascicular block (0%, 7%, 18%, 46%, p&amp;lt;0.001) and QRS fragmentation (2%, 11%, 25%, 23%, p=0.009) were more common in advanced stages. No differences were found in left bundle branch block (LBBB), in low QRS voltages or in LV pre-excitation prevalence. According with the wall thickness increase, negative T waves were more frequent in lateral (4%, 21%, 70%, 77%, p&amp;lt;0.001) and inferior leads (6%, 15%, 32%, 46%, p 0.001), as well as their association with ST-T depression (4%, 17%, 64%, 46%, p&amp;lt;0.001). Giant negative T waves were present only in group C and D (16% and 31%) mainly representing a LVH distribution toward the apex. Conclusions ECG is a very useful tool to stage cardiac involvement evolution in AFD. Peculiar ECG characteristics evolve together with LV wall thickness: incomplete and progressively complete RBBB usually associated (preceding or following) LVH and/or typical repolarization abnormalities in inferior or lateral leads and giant negative T waves in the more advanced stages are the most frequent and typical ECG patterns. Funding Acknowledgement Type of funding sources: None.

Electrocardiographic findings in Anderson-Fabry patients on disease specific therapy: can treatment prevent ECG changes?

Abstract Background Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder that have gained attention due to the availability of therapeutic options. Disease specific therapy (DST), either by enzyme replacement therapy or oral pharmacological chaperone, is the mainstay for AFD treatment. Although its widespread use, few data are available on the electrocardiographic variations associated with DST. Purpose To evaluate ECG findings and variations in AFD according to time duration of DST, comparing patients under long-term therapy with naïve patients starting therapy during follow-up. Methods One-hundred-seventy-nine AFD patients, ≥18 years old, with 2 readable ECGs, were recruited in the present multicentre study cohort. Two patients were excluded due to pacemaker (PM) implantation. Only patients on DST (n=107) were considered for final cohort and divided into 2 groups according to therapy duration: Group A (n=42) included patients treated for ≥12 months at the time of first evaluation, whereas Group B patients (n=65) started therapy during follow-up. Results Group A and Group B had no significant difference in terms of age at presentation (48 [39–60] vs 48 [36–56] years; p=0.856) and maximal wall thickness (13 [11–15] vs 13 [11–18] mm; p=0.090) whereas they differed for male prevalence (61% vs 38%; p=0.029) and classic phenotype (86% vs 29%; p&amp;lt;0.0001). At baseline, more than half of both groups had ECG abnormalities (61% vs 61%; p=1.000). The prevalence among Group A and Group B of atrial fibrillation (AF, 5% vs 6%; p=1.000), first degree atrioventricular block (AVB, 7% vs 5%; p=0.677), right bundle branch block (RBBB, complete 7% vs 8%; p=1.000; incomplete RBBB 14% vs 12%; p=0.776), left anterior fascicular block (LAFB, 10% vs 9%; p=1.000) and repolarization abnormalities (48% vs 38%; p=0.423) was not significantly different. Conversely, left ventricular hypertrophy (LVH) was more prevalent in Group A (64% vs 37%; p=0.010). During the follow-up period (57 [60–28] months for Group A vs 70 (37–85) months for Group B; p=0.152), both groups developed electrocardiographic alterations (38% vs 23%; p=0.127). In particular, in Group A, 4 (10%) patients presented AF, 1 (2%) AVB, 7 (17%) complete or incomplete RBBB, 4 (10%) LAFB, 1 (2%) LVH and 8 (19%) repolarization abnormalities. In Group B, 2 (3%) developed AF, 1 (2%) AVB, 7 (11%) complete or incomplete RBBB, 2 (3%) LVH and 11 (17%) repolarization abnormalities; none developed LAFB. Conclusions In this AFD cohort, both patients on chronic DST (Group A) and patients who started treatment during follow-up (Group B) developed ECG alterations. ECG changes during the follow-up were more frequent in Group A (38% vs 23%), mainly composed by classic phenotype and male patients, suggesting a prompt start of therapy at an early stage. Funding Acknowledgement Type of funding sources: None.

Membranous septum length as predictor for permanent pacemaker implantation after TAVI

Abstract Background High-degree atrioventricular (AV) block and permanent pacemaker (PPM) implantation represent major complications after transcatheter aortic valve implantation (TAVI). Extension of indication for TAVI towards subjects with lower surgical risk requires to reduce the likelihood for the requirement of permanent pacemaker (PPM) implantation. Data on the role of membranous septum length as potential predictor for AV block after TAVI are scarce. Purpose We examined the role of membranous septum length as potential predictor for AV block and the need for PPM implantation in a large cohort of consecutive subjects after TAVI. Methods In a cohort of 1365 patients without prior permanent pacemaker who underwent transfemoral TAVI, clinical and procedural characteristics were assessed systematically. Based on cardiac computed tomography performed prior to TAVI, membranous septum length was measured orthogonal to the anulus plane (see figure). Results Median age of subjects was 81 (IQR 7) years, 50% were male. Logistic euroSCORE was 12.8 (IQR 15.7), STS score 3 (2.7). 9,8% of subjects had a pre-interventional complete right bundle branch block (RBBB). 71% of patients received a balloon-expandable, 29% a self-expandable valve. In n=153 patients (11.2%), PPM implantation was necessary due to high-degree AV block. Median membranous septum length was 2.9 mm (IQR 2.5mm) in subjects who received a PPM versus 4.3 mm (IQR 3.2 mm) in subjects who did not need a PPM (p=0.061). In univariate regression analysis, pre-interventional complete RBBB (p&amp;lt;0.001, OR 7.8), implantation of a self-expandable prosthesis (p=0002, OR 1.7) and membranous septum length (p=0.027, OR 0.9 per 1 mm) were identified as significant predictors for PPM implantation. In multivariate regression analysis, all parameters remained significant, including membranous septum length (p=0.009, OR 0.9 per 1 mm). Conclusion In a large cohort of consecutive patients, we were able to confirm the significant independent predictive value of membranous septum length, in addition to pre-interventional complete RBBB or implantation of a self-expandable prosthesis, regarding the occurrence of post-procedural AV block with the need for PPM implantation. The results may contribute to improved risk stratification for potential PPM implantation after TAVI. Funding Acknowledgement Type of funding sources: None.

MORPHOLOGIC CHARACTERISTICS AND FUNCTION OF RIGHT VENTRICLE IN PATIENTS WITH ISOLATED RIGHT BUNDLE BRANCH BLOCK

Background: The prevalence of right bundle branch block (RBBB) is estimated in 0.2 to 1.3% of healthy people. RBBB had independent association with decreased right ventricle (RV) function, which is considered as predictor of adverse cardiovascular outcomes. The aim of this study is to evaluate RV structure and function in patients with isolated RBBB (without structural heart disease) using two-dimensional echocardiography. Methods: A cross-sectional study conducted at Chitwan Medical College, Bharatpur from 1st January 2022 to 30th June 2022. Consecutive adult patients aged ≥18 years with isolated RBBB classified into complete RBBB (CRBBB) and Incomplete RBBB (IRBBB) based on electrocardiographic findings. The echocardiographic evaluation was done to assess RV dimension and function. Results: A total of 52 patients with isolated RBBB were included with mean age of the study population was 45.3 ± 9.3 years, (28 ,53.8%) had CRBBB, whereas the remaining (24, 46.2%) had IRBBB. Among the parameters used to assess RV function; mean RV-Fractional area change (P&lt;0.001), Tricuspid annular plane systolic excursion(P&lt;0.02) and Pulsed Doppler peak velocity at the lateral annulus RV(P&lt;0.001) were significantly lower, while Pulsed Doppler myocardial performance index(P&lt;0.001) was significantly high in CRBBB group as compared to IRBBB group. Similarly, Right atrium and RV dimensional parameters were significant higher in CRBBB compared to IRBBB group. Conclusions: Isolated RBBB is not as benign as it was considered and has deteriorating effect on RV morphology and function. Therefore, patients with Isolated RBBB need follow-up with passing age and more attention toward RV structural and functional analysis.

Cardiocutaneous Syndrome: Naxos Disease

Naxos disease is a recessively inherited condition, caused by mutation in genes encoding desmosomal proteins Plakoglobin. It is characterized by peculiar woolly hair, palmoplantar keratoderma with arrhythmogenic Right Ventricular dysplasia /cardiomyopathy. A syndrome (a variant of Naxos) with same cutaneous phenotype and predominant Left Ventricular involvement is CARVAJAL syndrome. Patients are at risk of sudden cardiac death due to cardiomyopathy. We herein report a rare case of Naxos disease in a 16 years old male born of a 3º consanguineous marriage, presented with features suggestive of congestive cardiac failure with clubbing (grade 1), woolly hair, and focal keratoderma over palms and soles. ECG demonstrated – inverted T waves (V1-V3), QRS prolongation and complete RBBB. Echocardiography revealed-severe biventricular dysfunction with EF-15-20%, severe MR, severe TR and PAH. Patient was treated with diuretics, ß blockers and ACE inhibitors. These children may need implantation of automatic cardioverter defibrillator to prevent arrhythmogenic attacks and sudden cardiac death. CONCLUSION: For child with woolly hair and palmoplantar keratoderma, the pediatrician should provide a cardiac assessment, considering Naxos/Carvajal disease associated cardiomyopathy. When an early diagnosis is made, life expectancy can be increased by treatment of Heart failure and arrhythmias. Keywords: Naxos disease, Palmoplantar keratoderma, Cardiomyopathy, Wolly hair