High-degree Atrioventricular Block Research Articles

Comparison of Down Sizing Strategy (HANGZHOU Solution) and Standard Annulus Sizing Strategy in type 0 bicuspid aortic stenosis patients undergoing transcatheter aortic valve replacement: Rationale and design of a randomized clinical trial

BackgroundThere has not been a consensus on the prothesis sizing strategy in type 0 bicuspid aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). Modifications to standard annular sizing strategies might be required due to the distinct anatomical characteristics. We have devised a Down Sizing Strategy for TAVR using a self-expanding valve specifically for patients with type 0 bicuspid AS. The primary aim of this study is to compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy in TAVR for patients with type 0 bicuspid AS. Trial designIt is a prospective, multi-center, superiority, single-blinded, randomized controlled trial comparing the Down Sizing and Standard Annulus Sizing Strategy in patients with type 0 bicuspid aortic stenosis undergoing transcatheter aortic valve replacement. Eligible participants will include patients with severe type 0 bicuspid AS, as defined by criteria such as mean gradient across aortic valve ≥40 mmHg, peak aortic jet velocity ≥4.0 m/s, aortic valve area (AVA) ≤1.0 cm², or AVA index ≤0.6 cm2/m2. These patients will be randomly assigned, in a 1:1 ratio, to either the Down Sizing Strategy group or the Standard Sizing Strategy group. In the Down Sizing Strategy group, a valve one size smaller will be implanted if the “waist sign” manifests along with less than mild regurgitation during balloon pre-dilatation. The primary end point of the study is a composite of VARC-3 defined device success, absence of both permanent pacemaker implantation due to high-degree atrioventricular block and new-onset complete left bundle branch block. ConclusionThis study will compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy and provide valuable insights into the optimal approach for sizing in TAVR patients with type 0 bicuspid AS. We hypothesize that the Down Sizing Strategy will demonstrate superiority when compared to the Standard Annulus Sizing Strategy. (Down Sizing Strategy (HANGZHOU Solution) vs Standard Sizing Strategy TAVR in Bicuspid Aortic Stenosis (Type 0) (TAILOR-TAVR), NCT05511792)

E-5 | Predictive Factors for High-Degree Atrioventricular Block and Conduction Abnormalities Following Transcatheter Aortic Valve Replacement: Insights from a Comprehensive Meta-analysis

E-5 | Predictive Factors for High-Degree Atrioventricular Block and Conduction Abnormalities Following Transcatheter Aortic Valve Replacement: Insights from a Comprehensive Meta-analysis

Complications in emergency department patients with acute coronary syndrome with contemporary care.

With the implementation of early reperfusion therapy, the number of complications in patients with acute coronary syndrome (ACS) has diminished significantly. However, ACS patients are still routinely admitted to units with high-level monitoring such as the coronary or intensive care unit (CCU/ICU). The cost of these admissions is high and there is often a shortage of beds. The aim of this study was to analyze the complications in contemporary ED patients with ACS and to map patient management. This observational study was a secondary analysis of data collected in the ESC-TROP trial (NCT03421873) that included 26545 consecutive chest pain patients ≥ 18 years at five Swedish emergency departments (ED). Complications were defined as the following within 30 days: Death, cardiac arrest, cardiogenic shock, pulmonary edema, severe ventricular arrhythmia, high-degree AV-block that required a pacemaker, and mechanical complications such as papillary muscle rupture, cardiac tamponade, or ventricular septum defects (VSD). Complications were identified via diagnosis and/or intervention codes in the database, and manual chart review was performed in cases with complications. Of all 26545 patients, 2463 (9.3%) were diagnosed with ACS, and 151 of these (6.1%) suffered any complication within 30 days. Mean age was higher in patients with (79.2 years) than without (69.4 years) complications, and more were female (39.7% vs. 33.0%). Eighty-four (3.4% of all ACS patients) patients died, 33 (1.3%) had cardiac arrest, 22 (0.9%) respiratory failure, 13 (0.5%) high-degree AV block, 10 (0.4%) cardiogenic shock, 12 (0.5%) severe ventricular arrhythmia, and 2 each (<0.1%) had VSD or cardiac tamponade. Almost 30% of the complications were present already at the ED, and 40% of patients with complications were not admitted to the CCU/ICU. Only 80 (53%) of the patients with complications underwent coronary angiography and 62 (41%) were revascularized with PCI or CABG. With current care, serious complications occurred in only 6 out of 100 ACS patients, and 2 of these complications were present already at the ED. Four out of ten ACS patients with complications were not admitted to the CCU/ICU and about half did not undergo coronary angiography. Further research is needed to improve risk assessment in ED ACS patients, which may allow more effective use of cardiac monitoring and hospital resources.

Predictors, clinical impact, and management strategies for conduction abnormalities after transcatheter aortic valve replacement: an updated review.

Transcatheter aortic valve replacement (TAVR) has increasingly become a safe, feasible, and widely accepted alternative surgical treatment for patients with severe symptomatic aortic stenosis. However, the incidence of conduction abnormalities associated with TAVR, including left bundle branch block (LBBB) and high-degree atrioventricular block (HAVB), remains high and is often correlated with risk factors such as the severity of valvular calcification, preexisting conditions in patients, and procedural factors. The existing research results on the impact of post-TAVR conduction abnormalities and permanent pacemaker (PPM) requirements on prognosis, including all-cause mortality and rehospitalization, remain contradictory, with varied management strategies for post-TAVR conduction system diseases across different institutions. This review integrates the latest research in the field, offering a comprehensive discussion of the mechanisms, risk factors, consequences, and management of post-TAVR conduction abnormalities. This study provides insights into optimizing patient prognosis and explores the potential of novel strategies, such as conduction system pacing, to minimize the risk of adverse clinical outcomes.

Antiarrhythmic Effect of SGLT-2 Inhibitors in high-degree AV Block Caused by Heart Failure: A Case Report

Highlights: 1. The antiarrhythmic effect of SGLT-2 inhibitors, particularly empagliflozin, is a very interesting topic to discuss further. 2. In patients with high degree AV block due to HF in rural areas, the use of SGLT-2 inhibitors is quite rare in Indonesia. - Background: According to WHO's Top 10 Global Health Threats, non-communicable diseases such as heart failure contribute to more than 70% of all deaths worldwide. Several studies have shown that SGLT-2 inhibitors can considerably reduce HF. As research progresses, SGLT-2 inhibitors may lessen the risk of arrhythmias in HF patients. Case Summary: A 57-year-old female with uncontrolled hypertension came to the ED after collapsing at home. The vital signs and physical examination are normal. The preliminary ECG showed a high degree AV Block with multiple multifocal PVC. Early laboratory revealed mild hypokalemia. The patient experienced a seizure the next day, and an ECG showed total AV block with a non-sustained VT episode with PVC R on T. Following critical cardiac care and stabilization, the patient underwent echocardiography, which showed mild MR and AR with a reduced ejection fraction (47.7%). Once the patient's condition has stabilized, the patient is given 1x10mg Empagliflozin PO. Discussion: SGLT-2 inhibitors are beneficial in the treatment of heart failure and arrhythmia. SGLT-2 inhibitors have antiarrhythmic effects through a variety of pathways, such as lowering preload and afterload, inhibition of sodium-hydrogen exchange in myocardial cells, and suppression of the sympathetic nervous system.  

Assessment of the Impact of Cardiac Implantable Electronic Devices on Patients' Quality of Life.

Assessing the quality of life serves as a crucial metric during various therapeutic or surgical procedures. The rise in cardiac electronic device implantations in recent years underscores the significance of evaluating the quality of life among such patients. We conducted a study focusing on the quality of life of 438 patients with cardiac implantable electronic devices (cardiac pacemakers, cardioverter-defibrillators, cardiac resynchronization therapy devices). These patients were diagnosed with sick sinus syndrome, high-degree atrioventricular (AV) block, or severe heart failure (New York Heart Association (NYHA) classes III- IV (NYHA III-IV)), with left ventricular ejection fraction (LVEF) ≤ 35%, with/without complete left bundle branch block (QRS ≥ 130 μs), or with a history of ventricular tachycardia/ventricular fibrillation. The study utilized the EuroQol 5-Dimension 5-level (EQ-5D-5L) questionnaire and the EQ visual analog scale, which patients completed both prior to cardiac device implantation and during six post-implantation follow-up visits. The analysis of the research findings was conducted using the IBM SPSS Statistics software program (Armonk, NY). Cardiac pacemaker implantation in patients with sick sinus syndrome and high-grade AV block demonstrated significant and highly reliable positive effects on quality of life concerning mobility, self-care, and usual activity. Similarly, cardiac resynchronization device implantation in individuals with severe heart failure with reduced LVEF and wide QRS showed significant positive effects in these areas. However, cardioverter-defibrillator implantation did not yield positive effects on these modules.Regarding pain/discomfort, neither pacemaker nor cardiac resynchronization device implantation resulted in improved quality of life, while there was a somewhat positive effect observed in the cardioverter-defibrillator group. In terms of anxiety/depression, pacemaker implantation in patients with sick sinus syndrome and high-degree AV block had a significant and highly reliable positive impact on quality of life. Additionally, relatively positive impacts were noted at various periods following cardioverter-defibrillator and cardiac resynchronization device implantations. Cardiac implantable electronic devices play a crucial role not only in saving lives but also in positively impacting the quality of life of patients when appropriately selected.

Transvenous endocardial pacing with SelectSecure™ 3830 lead in pediatric patients: case series of two infants and a literature review

BackgroundThe SelectSecure™ 3830 lead is an innovative, lumenless, and thin active fixed lead with a nonretractable screw-in tip and a diameter of 4.1 Fr, making it the thinnest pacing lead available. Its high anti-extrusion properties and durability have shown favorable outcomes in cardiac pacing, especially in pediatric patients. The superfine design and easy implantation of the lead have rendered it a preferred choice in children, particularly in cases of congenital heart disease.Case presentationThis case series presents two infant patients who underwent transvenous endocardial pacing using the SelectSecure™ 3830 lead, along with a comprehensive literature review on the topic. The study followed the patients for 5 years and 3 years, respectively, and observed stable pacing parameters, indicating a positive therapeutic outcome and safety.This article discusses the optimal age and body shape for transvenous lead implantation in infants and highlights the advantages and disadvantages of endocardial and epicardial pacing approaches. Although endocardial pacing offers several benefits such as minimal trauma, short hospital stay, and longer battery life, it may not be suitable for intracardiac shunts, and venous occlusion remains a concern. On the other hand, epicardial pacing may be considered for children with challenging endocardial access but comes with higher risk of lead failure and coronary artery compression.This study emphasizes the importance of careful follow-up in pediatric patients with pacing, as lead failure can occur in young patients owing to growth and development, leading to syncope and battery depletion. The article also underscores the significance of selecting the appropriate pacing location to minimize the impact of cardiac function, with right ventricular septal pacing emerging as a preferable option.ConclusionsThe SelectSecure™ 3830 lead presents a promising solution for transvenous endocardial pacing in pediatric patients with high degree atrioventricular block and bradycardia, ensuring safe and effective pacing as they grow and develop.

Prevalence of transthyretin cardiac amyloidosis in patients with high-degree AV block

ObjectiveTransthyretin amyloid cardiomyopathy (ATTR-CM) is an infiltrative cardiac disorder caused by deposition of wild type or mutated transthyretin. As ATTR-CM is associated with conduction disease, we sought to determine its...

The Transcatheter Aortic Valve Replacement-Conduction Study: The Value of the His-Ventricular Interval in Risk Stratification for Post-TAVR Atrioventricular-Block

BackgroundThere is no clear consensus regarding the optimal risk stratification of high-degree atrioventricular block (HDAVB) after transcatheter aortic valve replacement (TAVR). MethodsThis prospective study sought to determine the utility of the pre- and post-TAVR His-ventricular (HV) interval in the risk stratification of post-TAVR HDAVB. One hundred twenty-one patients underwent an electrophysiology study before and after TAVR. The primary outcome was HDAVB requiring pacemaker implantation within 30 days post-TAVR. A separate retrospective cohort was analyzed to determine the postoperative interval at which the risk of HDAVB is reduced to <5%. ResultsHDAVB occurred in 12 (10%) patients. Baseline right bundle branch block (RBBB) (odds ratio [OR]: 13.6), implant depth >4 mm (OR: 3.9), use of mechanically- or self-expanding valves (OR: 6.3), and post-TAVR HV > 65 ​ms (OR: 4.9) were associated with increased risk of HDAVB, whereas PR intervals and pre-TAVR HV were not. In patients without baseline RBBB or new persistent left bundle branch block (LBBB), not one patient with post-TAVR HV < 65 ​ms developed HDAVB. In the separate retrospective cohort (N = 1049), the risk of HDAVB is reduced (<5%) on postoperative days 4 and 3 in patients with pre-TAVR RBBB and post-TAVR persistent LBBB, respectively. ConclusionsBaseline RBBB, new persistent LBBB, implant depth >4 mm, and a post-TAVR HV ≥ 65 ​ms were associated with a higher risk of post-TAVR HDAVB, whereas an HV ≤ 65 ​ms was associated with a lower risk. The pre-TAVR HV was not associated with our outcome, and the delta HV did not have practical incremental prognostic value. Among those without pre-TAVR RBBB or post-TAVR persistent LBBB, no patients with post-TAVR HV < 65 ​ms developed HDAVB.

Incidental Arrhythmias During Atrial Fibrillation Screening With Repeat 7-Day Holter ECGs in a Hospital-Based Patient Population.

Screening for atrial fibrillation (AF) may reveal incidental arrhythmias of relevance. The aim of this study was to describe incidental arrhythmias detected during screening for AF in the STAR-FIB (Predicting SilenT AtRial FIBrillation in Patients at High Thrombembolic Risk) cohort study. In the STAR-FIB cohort study, we screened hospitalized patients for AF with 3 repeat 7-day Holter ECGs. We analyzed all Holter ECGs for the presence of the following incidental arrhythmias: (1) sinus node dysfunction, defined as sinus pause of ≥3 seconds' duration; (2) second-degree (including Wenckebach) or higher-degree atrioventricular block (AVB); (3) sustained supraventricular tachycardia of ≥30 seconds' duration; and (4) sustained ventricular tachycardia of ≥30 seconds' duration. We furthermore report treatment decisions because of incidental arrhythmias. A total of 2077 Holter ECGs were performed in 794 patients (mean age, 74.7 years; 49% women), resulting in a mean cumulative duration of analyzable ECG signal of 414±136 hours/patient. We found incidental arrhythmias in 94 patients (11.8%). Among these were sinus node dysfunction in 14 patients (1.8%), AVB in 41 (5.2%), supraventricular tachycardia in 42 (5.3%), and ventricular tachycardia in 2 (0.3%). Second-degree AVB was found in 23 patients (2.9%), 2:1 AVB in 10 (1.3%), and complete AVB in 8 (1%). Subsequently, 8 patients underwent pacemaker implantation, 1 for sinus node dysfunction (post-AF conversion pause of 9 seconds) and 7 for advanced AVB. One patient had an implantable cardioverter-defibrillator implanted for syncopal ventricular tachycardia. Incidental arrhythmias were frequently detected during screening for AF in the STAR-FIB study and resulted in device therapy in 1.1% of our cohort patients.

Risk Factors of Long-Term Sequelae After Transcatheter Closure of Perimembranous Ventricular Septal Defect in Young Children.

Complications arising from transcatheter closure of perimembranous ventricular septal defects (pmVSD) in children, such as residual shunts and aortic regurgitation (AR), have been observed. However, the associated risk factors remain unclear. This study identified risk factors linked with residual shunts and AR following transcatheter closure of pmVSD in children aged 2-12 years.Methods and Results: The medical records of 63 children with pmVSD and a pulmonary-to-systemic blood flow ratio <2.0 who underwent transcatheter closure between 2011 and 2018 were analyzed with a minimum 3-year follow-up. The success rate of transcatheter closure was 98.4%, with no emergency surgery, permanent high-degree atrioventricular block, or mortality. Defects ≥4.5 mm had significantly higher odds of persistent residual shunt (odds ratio [OR] 6.85; P=0.03). The use of an oversize device (≥1.5 mm) showed a trend towards reducing residual shunts (OR 0.23; P=0.06). Age <4 years (OR 27.38; 95% confidence interval [CI] 2.33-321.68) and perimembranous outlet-type VSD (OR 11.94, 95% CI 1.10-129.81) were independent risk factors for AR progression after closure. Careful attention is crucial for pmVSDs ≥4.5 mm to prevent persistent residual shunts in transcatheter closure. Assessing AR risk, particularly in children aged <4 years, is essential while considering the benefits of pmVSD closure.

Cardiac Damage and Conduction Disorders after Transcatheter Aortic Valve Implantation.

Recently, a staging system using 4 grades has been proposed to quantify the extent of cardiac damage associated with aortic stenosis (AS), namely AS-related cardiac damage staging (ASCDS). ASCDS is independently associated with all-cause mortality and important clinical outcomes. To evaluate whether it might be associated with the occurrence of conduction system disorders after TAVI, a total of 119 symptomatic patients with severe AS who underwent a TAVI were categorized according to ASCDS: group 1 (13.5%): no or LV damage; group 2 (58.8%): left atrial/mitral valve damage, atrial fibrillation (AF); group 3 (27.7%): low-flow state, pulmonary vasculature/tricuspid valve/RV damage. After TAVI, 34% of patients exhibited LBBB and 10% high-degree atrioventricular block (HD-AVB). No patient in group 1 developed HD-AVB whereas new LBBB was frequent in groups 2 and 3. Twenty-one patients presented with paroxysmal AF with a higher rate for each group increment (group 1: n = 0, 0%; group 2: n = 11, 15.7%; group 3: n = 10, 30.3%) (p = 0.012). Patients in group 3 had the higher rate of permanent pacemaker implantation (PPMI) (group 1: n = 1, 6.3%; group 2: n = 7, 10%; group 3: n = 9, 27.3%) (p = 0.012). In conclusion, ASCDS might help identify patients at higher risk of conduction disorders and PPMI requirement after TAVI.

How Long is Too Long? Asymptomatic Nocturnal Pauses in Athletes: A Narrative Review

Athletes undergo mandatory or voluntary cardiac testing, which may include 24-h ambulatory electrocardiogram monitoring. This study can on occasion disclose nocturnal pauses in otherwise asymptomatic healthy individuals. In some athletes, particularly those engaging in endurance or mixed sports, the pauses can be longer than 2–3 s and/or be caused by sinus arrest high-degree atrioventricular block not typical for physiological adaptation to exercise. The manuscript discusses the physiology and potential pathologies behind long nocturnal pauses in athletes. Several management strategies are proposed including emerging treatment techniques such as cardioneuroablation.

Relationship between CTGF levels and echocardiographic parameters in patients after permanent pacemaker implantation

Introduction: In recent decades, the dual-chamber pacemaker has become the gold standard for treating high-degree atrioventricular block. Despite the incredible benefits of overcoming conduction disorders, undeniable evidence has accumulated in recent years of negative effects of permanent right ventricular apical stimulation. The aim of our study was to examine the cytokines responsible for activation of the fibrotic process in patients after PPM implantation with apical right ventricular stimulation. Material and Methods: CTGF levels were investigated by enzyme-linked immunoassays in plasma from 45 patients (25 men, 20 women, aged 72.1±9 years) and 46 controls (24 men, 22 women, aged 71.9±8.7 years) without known cardiovascular diseases (except arterial hypertension, conduction disorder, indication for the procedure) at baseline (for patients immediately before PPM implantation), at 12 and 24 weeks. At the same visits echocardiography was performed. Results: There was no difference in baseline CTGF levels between patients and controls (312.66±15.25 vs 313.05±12.98 p&gt;0.05). In patients, at week 12, CTGF levels were significantly increased compared to baseline in controls (627.74±41.81 vs 313.05±12.98 pg/ml p&lt;0.001). At week 24, values continued to increase, being again significantly higher than baseline in controls (400.83±13.29 vs 313.05±12.98 pg/ml p&lt;0.001). Conclusion: Our data analysis gives us reason to conclude that there is a significant increase in the levels of the growth factor after PPM implantation and it plays a major role in fibrotic remodeling of the myocardium. We guess increase in filling pressure of the left ventricle that is followed by LA pressure load and is a prerequisite for its dilatation.

Is left bundle branch pacing (LBBP) associated with better depolarization and repolarization kinetics than right ventricular mid septal pacing (RVSP)? - Comparison of frontal QRS -T angle in patients with LBBP, RVSP and normal ventricular conduction

AimsTo assess the frontal QRS- T angle (f QRS- T angle) in patients with left bundle branch pacing (LBBP) as compared to right ventricular mid septal pacing (RVSP) implanted for symptomatic high degree atrioventricular (AV) block and to compare with control subjects with normal ventricular conduction (CSNVC) MethodsA total of one-fifty subjects were chosen (50 patients with LBBP, 50 patients with RVSP and 50 CSNVC). The indication for pacemaker implantation was symptomatic high degree AV block. Baseline clinical and electrocardiogram (ECG) parameters like QRS duration (QRSD), QRS axis and f QRS-T angle and Ejection Fraction (EF) were assessed. f QRS-T angle was measured as the difference between the computerised mean frontal QRS and T wave axes in the limb leads. If the difference between the QRS axis and T-wave axis exceeds 180°, then the resultant QRS-T angle would be calculated as 360° minus the absolute angle to obtain a value between 0° and 180°. Baseline, immediate post procedural and 6 month follow up (f/u) ECGs and EF were chosen for the analysis. ResultsPatients who underwent LBBP had significantly shorter paced QRSD than patients who had undergone RVSP (112 ± 12 ms vs 146 ± 13 ms; 95 % confidence interval (CI): 43, −31; p<0.001). There was no significant difference in the QRSD before and after LBBP. The QRSD before and after pacing in RVSP was 111 ± 27 ms and 146 ± 13 ms; 95 % CI: 43, −28; p < 0.001. The QRSD in control patients with NVC was 82.94 ± 9.59 ms.RVSP was associated with wider f QRS-T angle when compared with LBBP (103 ± 53° vs 82 ± 43°; 95 % CI: 39, −1.0; p = 0.037). The baseline and immediate post procedure f QRS-T angle in LBBP was 70 ± 48° and 82 ± 43°; 95 % CI: 31, 5.3; p = 0.2. At 6 months f/u, the f QRS-T angle was 61 ± 43°; 95 % CI: 8.5, 35; p=0.002. The baseline and immediate post procedure f QRS-T angle in RVSP was 67 ± 51° and 103 ± 53°; 95 % CI: 54, −17; p < 0.001. At 6 months f/u, the f QRS-T angle in RVSP group was 87 ± 58°; 95 % CI: 2.6, 29; p = 0.020. The f QRS T angle in control patients with NVC was 24 ± 16°. When subgroup analysis was done the difference in the f QRS-T angle was significant between RVSP and LBBP groups only in patients who had wide QRS escape.The mean LVEF at 6-month follow-up in LBBP vs RVSP was 61 ± 3.7 % vs 57.1 ± 7.8 %; 95 % CI:1.48, 6.32, p = 0.002. In the RVSP group, three patients developed pacing induced cardiomyopathy (PIC) whereas no patients in the LBBP group developed PIC at 6-month follow-up; p=0.021. One patient with PIC had deterioration of functional status with new onset HF symptoms. The patient symptoms improved with medical therapy and needed no hospitalisation. The patient declined further interventions including upgradation to CRT or LBB pacing. No deaths or ventricular arrhythmias were observed during the study period. ConclusionLBBP is associated with narrower f QRS-T angle as compared to RVSP both at post implant period and at 6 month f/u period. These findings might be due to the more physiological depolarization and repolarization kinetics associated with LBBP. RVSP was associated with 6 % incidence of PIC. Hence wide f QRS-T angle might be a predictor of PIC.

Atypical Wenckebach without grouped beating due to dual AV nodal conduction

A 31-year-old woman reported dizziness in the early postpartum period after receiving dexmedetomidine. The ECG was misinterpreted as complete heart block; however, more careful analysis revealed an atypical Wenckebach pattern with dual AV nodal conduction and termination of nonconducted P waves with junctional escape beats. The patient's rhythm returned to sinus after stopping dexmedetomidine.Atypical Wenckebach patterns account for greater than 50% of patients with Mobitz Type I AV block and can be misinterpreted as high-grade AV block. This case highlights the causes of atypical Wenckebach patterns and how careful analysis of intervals can help clinicians avoid misdiagnosis.

High prevalence and distinctive clinical features of LMNA-associated atrioventricular block in young patients

Atrioventricular block (AVB) is a degenerative disease and more commonly encountered in elderly patients, but unusual and often of unknown etiology in young patients. This study aimed to investigate the potential contributions of genetic variations to AVB of unknown reasons in young patients. We enrolled 41 patients aged <55 years with high-degree AVB of unknown etiology whose clinical and genetic data were collected. Genetic variants were identified in 20 (20/41, 48.8%) patients, 11 (11/20, 55%) of whom had LMNA variants including 3 pathogenic (c.961C > T, c.936+1G > T and c.646C > T), 4 likely pathogenic (c.1489-1G > C, c.265C > A, c.1609-2A > G and c.1129C > T) and 3 of uncertain significance (c.1158-3C > G, c.776A > G and c.674G > T). Compared to those without LMNA variants, patients with LMNA variants demonstrated a later age at onset of AVB (41.45 ± 9.89 years vs 32.93 ± 12.07 years, P = .043), had more prevalent family history of cardiac events (81.8% vs 16.7%, P < .000), suffered more frequently atrial (81.8% vs 10.0%, P < .000) and ventricular (72.7% vs 10.0%, P < .000) arrhythmias, and were more significantly associated with enlargement of left atrium (39.91 ± 7.83 mm vs 34.30 ± 7.54 mm, P = .043) and left ventricle (53.27 ± 8.53 mm vs 47.77 ± 6.66 mm, P = .036). Our findings provide insights into the genetic etiology of AVB in young patients. LMNA variants are predominant in genotype positive patients and relevant to distinctive phenotypic properties.

Prevalence of Cardiac Sarcoidosis in Middle-Aged Adults Diagnosed with High-Grade Atrioventricular Block

IntroductionAtrioventricular block may be idiopathic or a secondary manifestation of an underlying systemic disease. Cardiac sarcoidosis is a significant underlying cause of high-grade atrioventricular block, posing diagnostic challenges and significant clinical implications. This study aimed to assess the prevalence and clinical characteristics of cardiac sarcoidosis among younger patients presenting with unexplained high-grade atrioventricular block. MethodsWe evaluated patients aged between 18 and 65 years presenting with unexplained high-grade atrioventricular block, who were systematically referred for cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, prior to pacemaker implantation. Subjects with suspected cardiac sarcoidosis based on imaging findings were further referred for tissue biopsy. Cardiac sarcoidosis diagnosis was confirmed based on biopsy results. ResultsOverall, 30 patients with high-grade atrioventricular block were included in the analysis. The median age was 56.5 years (interquartile range 53-61.75, years). In 37%, cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, were suggestive of cardiac sarcoidosis, and in 33% cardiac sarcoidosis was confirmed by tissue biopsy. Compared with idiopathic high-grade atrioventricular block patients, all cardiac sarcoidosis patients were males (100% vs 60%, P = .029), were more likely to present with heart failure symptoms (50% vs 10%, P = .047), had thicker inter-ventricular septum on echocardiography (12.2 ± 2.7 mm vs 9.45 ± 1.6 mm, P = .002), and were more likely to present with right ventricular dysfunction (33% vs 10%, P = .047). ConclusionsCardiac sarcoidosis was confirmed in one-third of patients ≤ 65 years, who presented with unexplained high-grade atrioventricular block. Cardiac sarcoidosis should be highly suspected in such patients, particularly in males who present with heart failure symptoms or exhibit thicker inter-ventricular septum and right ventricular dysfunction on echocardiography.

The R-Wave amplitude in V1 on baseline ECG correlates with the occurrence of high-degree atrioventricular block following left bundle branch block after transcatheter aortic valve replacement

Abstract Aims Several procedural and ECG parameters have been associated with the occurrence of high-degree atrioventricular block (AVB) requiring permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement (TAVR). We hereunder sought to assess if the baseline R-wave amplitude in V1 ECG-lead of patients with normal QRS duration undergoing TAVR is associated with a higher patient’s risk for developing high-degree AVB following left bundle branch block (LBBB). Methods and Results In this retrospective single-center study in 720 consecutive patients who underwent TAVR, 141 (19.6%) patients with normal QRS duration developed a new LBBB after TAVR. The 24 (17%) patients who underwent PPI for reasons other than high-degree AVB were excluded from further analysis. In the remaining 117 study patients, 14 (12%) developed high-degree AVB requiring PPI (Group 1) while the remaining 103 (88%) patients did not (Group 2). There were no significant differences in baseline demographic or procedural characteristics nor in PR interval, QRS duration and QRS axis between these 2 groups. The incidence of left anterior hemiblock was higher in Group 1 (3 of 14, 21.4%) than in Group 2 (9 of 103, 8.7%) but the difference was not statistically significant (p=0.156). The R-wave amplitude in V1 was smaller in Group 1 than in Group 2 (0.029±0.04mV vs. 0.11±0.14mV, p=0.0316). In the receiver operating characteristics analysis, the cutoff for R-wave amplitude pre-TAVR was 0.03mV, area under the curve=0.7219, (p=0.0002). Conclusion The R-wave amplitude in lead V1 during baseline ECG in patients with normal QRS duration may predict the occurrence of high-degree AVB following new LBBB after TAVR.Figure 1.ROC AnalysisFigure 2.Representative case

Prevalence and prognostic value of significant mitral regurgitation development after pacemaker implantation

Abstract Background Mitral regurgitation (MR) is one of the complications after pacemaker (PM) implantation. However, the underlying mechanism leading to MR progression after PM implantation is not yet fully understood. There is also a lack of information on the clinical impact of the development of MR after PM implantation. Purpose This study aims to evaluate the prevalence and mechanism of MR progression after PM implantation and to determine its prognostic value. Methods Patients who underwent de novo PM implantation at our university medical centre between 2010 and 2020 were included. Patients with previous mitral valve surgery, transcatheter edge-to-edge repair, or MR severity ≥ moderate before device implantation were excluded. The development of significant MR was defined as a worsening of MR severity ≥ moderate within five years after PM implantation. Clinical endpoints were defined as a composite of all-cause mortality or heart failure hospitalization. Results A total of 451 patients (mean age 69 ± 15 years, 61% male) were included. High-degree atrioventricular block (76%) was the main indication for PM implantation. Dual-chamber PM was implanted in 370 (82%) patients. The development of significant MR occurred in 131 (29%) patients at a median of 2.4 years [interquartile range (IQR): 1.0-3.8 years] after PM implantation. Multivariate logistic regression analysis demonstrated that implanted single-chamber PM, LV end-systolic volume index (LVESVI), and mild MR (vs no MR) at baseline were independently associated with the development of significant MR. Prespecified endpoints occurred in 143 patients (31.7%) during median follow-up of 5.4 years [IQR: 3.0-8.1 years] after PM implantation. The Kaplan-Meier analysis showed that patients with significant MR after PM implantation had a significantly higher incidence of endpoints than those without. (Figure) Multivariate Cox regression analysis demonstrated that the development of significant MR, age, male gender, and diabetes mellitus were independently associated with the occurrence of the combined endpoints. The development of significant MR had significant incremental prognostic value for the composite endpoints over the multivariate models including a decrease in LV ejection fraction of ≥ 10% (p = 0.008) or an increase in LVESVI of ≥ 20% (p = 0.016) after PM implantation. Conclusions The development of significant MR occurred in 131 patients after PM implantation. The development of significant MR was independently associated with cardiac events, and its prognostic value was also significant even when included in models including a decrease in LV ejection fraction or an increase in LVESVI after PM implantation.Figure:Kaplan-Meier Curve