3rd Degree Atrioventricular Block Research Articles

Feasibility and safety of permanent left bundle branch area pacing in pediatric patients

Abstract Introduction Left bundle branch area pacing (LBBAP) is a promising pacing strategy with a low and stable pacing threshold. It maintains electrical and mechanical synchronization of the ventricles. Conduction system pacing (CSP) has evolved rapidly to become the pacing method of choice for many adult and pediatric patients. Recent studies have begun to demonstrate the feasibility and efficacy of CSP in pediatric patients. Nowadays, research articles about LBBAP in children are comparatively rare, therefore, research in this area is preferred. Limited data on LBBAP in pediatric patients (≤ 18 years old) are available. Purpose This study aims to describe the feasibility and safety of LBBAP in pediatric patients. Methods This study includes 4 patients: 1 male, and 3 females, respectively. The average age of the patients was 15.5±1.9 years and the weight was 51,5±17,6 kg. All patients were diagnosed with 3rd-degree atrioventricular (AV) block, in one case the total AV block occurred after previous radiofrequency ablation of the parahisian and right lateral accessory pathway. One patient had previously been implanted with an epicardial pacemaker and presented to our clinic with ventricular lead dysfunction. Pacing parameters were assessed during implantation, the next day after the procedure, and 1, 3 months follow-up. Echocardiography was performed to evaluate LV function and assess the approximate lead location and impact on tricuspid valve function. Results LBBAP was successfully achieved in all patients resulting in narrow QRS complexes (102±12.7ms) and right bundle branch block QRS morphology. To confirm left bundle branch area capture, peak left ventricular activation time (pLVAT) (84.5±4.1ms), V6-V1 (43.5±2.5ms) inter-peak interval, presence of left bundle potential, transition from non-selective to selective capture were recorded at during the implantation. The mean paced QRS duration was (108±13 ms). Pacing threshold and impedance remain stable (0.75±0.25V, and 615±50 Ohm, respectively). There was no major complication during the implanting process and follow-up. Conclusions LBBAP can be performed safely in children with narrow QRS complexes and can achieve stable pacing parameters.

Association between Preeclampsia and Long-term Risk of Arrhythmias.

Preeclampsia (PE), a pregnancy-induced hypertensive disorder, affects 4-5% of pregnancies worldwide. It is well known that hypertension is associated with an increased risk of arrhythmias; however, data on the association between PE and arrhythmias are sparse. In this observational cohort study, we identified all primiparous women who gave birth in Denmark (1997-2016) using Danish nationwide registries. The women were stratified on whether they developed PE during primiparous pregnancy, and followed from primiparous pregnancy to incident arrhythmia, emigration, death, or end of study (December 31, 2018). A total of 523,271 primiparous women with a median age of 28 years were included and 23,367 (4.5%) were diagnosed with PE. During a median follow-up of 10.1 years, women with vs without PE were associated with a higher incidence of arrhythmias (1.42% vs 1.02%): 1) Composite of cardiac arrest, ventricular tachycardia/fibrillation, or ICD implantation (adjusted HR 1.60 [95% CI 1.14-2.24]), 2) Composite of advanced 2nd degree or 3rd degree atrioventricular block, sinoatrial dysfunction, or pacemaker implantation (adjusted HR 1.48 [95% CI 0.97-2.23]), 3) Composite of supraventricular tachyarrhythmias or extra systoles (adjusted HR 1.34 [95% CI 1.19-1.51]), 4) Composite of all the above-mentioned arrhythmias (adjusted HR 1.37 [95% CI 1.23-1.54]). Preeclamptic women were associated with a significantly and at hitherto unknown long-term increased rate of arrhythmias. This finding suggests that women with PE may benefit from cardiovascular risk assessment, screening, and preventive education.

Association between preeclampsia and long-term risk of arrhythmias

Abstract Background Preeclampsia (PE), a pregnancy-induced hypertensive disorder, affects 4-5% of pregnancies worldwide. It is well known that hypertension is associated with increased risk of arrhythmias; however, data on the association between PE and arrhythmias are sparse and there is a lack of knowledge on the long-term risk of arrhythmias. Purpose To compare the incidence of arrhythmias following preeclamptic and normotensive pregnancies. Methods In this observational cohort study, we identified all primiparous women without history of arrhythmias who gave birth in Denmark from 1997 to 2016 using Danish nationwide registries. The women were stratified on whether they developed PE during their primiparous pregnancy and were followed from primiparous pregnancy to incident arrhythmia, emigration, death, or end of study (December 31, 2018). The comparative risks of arrhythmias were assessed in cause-specific Cox regression analyses adjusted for known arrhythmogenic risk factors including obesity, smoking, hypertension, coronary artery disease, cardiomyopathy, congenital heart disease, thyroid disease, diabetes, and alcohol abuse. Results A total of 521,517 primiparous women with a median age of 28 years were included and 23,523 (4.5%) were diagnosed with PE. Women with versus without PE were of similar age but had a higher burden of comorbidities. During a median follow-up period of 10.2 years, women with PE were associated with higher absolute incidences of arrhythmias (Figure 1). No statistically significant association was found for the composite of cardiac arrest, ventricular arrhythmias, or ICD-implantation nor for the composite of advanced 2nd or 3rd degree atrioventricular block, sinoatrial dysfunction, or pacemaker-implantation. However, women with PE were associated with a significant increased risk of the composite of supraventricular tachyarrhythmias and extrasystoles (p<0.01) and the composite of all included arrhythmias (p<0.01). Factors associated with arrhythmias among women with PE included obesity (HR 1.40 (95%CI 1.03-1.91), coronary artery disease (HR 2.39 (95%CI 1.14-5.00), cardiomyopathy (HR 9.65 (95%CI 3.46-26.92), and congenital heart disease (HR 5.86 (95%CI 2.59-13.28). Conclusion Preeclamptic women were associated with a significantly higher rate of arrhythmias - mainly driven by supraventricular tachyarrhythmias and extrasystoles - than normotensive women. For the purpose of primary and secondary prevention, this finding suggests that women with a history of PE may benefit from evaluation of cardiovascular risk factors, screening of and education in prevention of cardiovascular disease.Figure 1

Concomitant Electrophysiological Study with Transcatheter Aortic Valve Implantation to Predict Risk of Atrioventricular Block

Introduction: Data on the impact of left bundle-branch block after transcatheter aortic valve implantation (TAVI) are scarce, and treatment has been individualized. Based on this, the electrophysiological study (EPS) concomitant with TAVI may be a strategy for the early stratification of patients needing permanent pacemaker implantation (PPM). Objective: To describe the use of EPS in risk stratification of a definitive pacemaker in patients undergoing TAVI. Materials and methods: Data from seven patients with indications for TAVI due to critical aortic stenosis were retrospectively evaluated. The EPS was performed with a quadripolar diagnostic catheter in His bundle to measure the His-ventricle (HV) interval. Measurement of HV at 70 ms or above was used for discussion on PPM implant indication. Results: Four analyzed patients evolved with left bundle-branch block after TAVI. PPM implantation was indicated for one patient, and the surgery was performed uneventfully during the same hospital stay. Before TAVI, the HV interval ranged from 46 to 58 ms (mean = 53.2 ms), increasing to 52 to 84 ms (mean = 62.8 ms) immediately after valve intervention. Conclusion: The strategy of EPS during TAVI is viable to stratify patients early according to the risk of 2nd or 3rd-degree atrioventricular block, allowing adequate treatment.

Invasive electrophysiology study guided loop recorder implantation in myotonic dystrophy type 1: a prospective single-center study

Abstract Funding Acknowledgements Type of funding sources: None. Introduction In one third of the patients with myotonic dystrophy type 1 (DMT1) the cause of death is of cardiac origin. The most common cardiac manifestations are arrhythmias and conduction disturbances. Purpose Due to its extreme long monitoring properties, implantable loop recorders (ILRs) are highly suitable to detect rare cardiac arrhythmias. To date, there are only limited data using ILRs in DMT1. We aimed to evaluate the role of the invasive electrophysiology study (EPS)-guided loop recorder implantation in patients with DMT. Methods In our prospective study 18 genetically confirmed DMT1 patients underwent non-invasive cardiac examination including transthoracic echocardiography, 24-hour Holter monitoring and surface ECG. In addition, EPS was performed in all cases to evaluate the risk of sudden cardiac death and infra-Hisian conduction properties. Based on the performed non-invasive diagnostic evaluation and EPS findings, patients were divided into low, intermediate and high-risk groups. For patients with normal investigation results and normal HV interval (<55 ms) only annual cardiac follow-up visits were planned (low-risk group). Patients with increased PR interval (>240 ms), QRS duration (>120 ms), or slightly prolonged HV interval (55-70 ms) underwent implantable loop recorder (ILR) implantation (intermediate-risk group). Permanent pacemaker (PM) or implantable cardiac defibrillator (ICD) was implanted in patients with 2nd/3rd degree atrioventricular block (AVB), significantly prolonged HV interval (>100 ms) or if sustained ventricular tachyarrhythmia could be induced during EPS. All patients were followed for at least 3 years. Results According to our study criteria, 8 patients could be categorized as "intermediate risk", 7 of them received implantable loop recorder (ILR). 1 ILR had to be removed 3 weeks after implantation due to skin infarction. During three-years of follow-up, 2 patients had many asymptomatic atrial high-rate episodes, but no 2nd or 3rd degree AVB, significant asystole or malignant ventricular arrhythmia were detected. Conclusions Our single-center prospective study examined the EPS-guided ILR implantation for the risk stratification of DMT1 patients for the first time. A more extensive, multicenter study is warranted to define optimal management of DMT1 patients with slightly impaired infrahisian conduction.

Optimizing atrial sensing parameters in leadless pacemakers: main findings of the OptiVALL study

Abstract Funding Acknowledgements Type of funding sources: None. Backgroung: The MARVEL2 study demonstrated the feasibility of leadless pacemakers in delivering atrioventricular (AV) synchronous pacing with an accelerometer-based algorithm, for up to 5 h. Purpose To assess the AV synchrony (AVS) the device can provide under daily activities and across different heart rate (HR) ranges, and to describe what programming changes are needed to achieve proper atrial tracking and AVS. Methods The OptiVALL study is a single-centre and prospective study of consecutive patients implanted with MICRA AV. Follow-up was routinely performed at 24 hours and at 1, 3, 6 and 12 months. The pacing mode was programmed to VDD in all patients and AV conduction mode switch (VVI +) was deactivated. In each visit a device check was carried out and reprogramming of the atrial sensing parameters was performed according to the manual atrial mechanical tests, as well as information from device counters and rate histograms. A 24-h Holter monitoring was placed at 3-months follow-up and ECG recorded tracings were automatically and blindly analyzed with an ECG delineation system. Cardiac cycles were defined as synchronous if a ventricular event followed the P-wave by ≤300 ms. AVS was calculated by dividing the number of synchronous cycles by the total number of cardiac cycles. The primary efficacy endpoint was defined as AVS≥ 85% of total cardiac cycles during the 24-h Holter-ECG monitor. AVS was also calculated for each HR range of 10 bpm. Results Thirty-two patients (18 males, mean age 78.8 ±15.1, 16 patients with 3rd degree AV block, 15 patients with 2nd degree AV block, 1 patient with bifascicular block) underwent successful Micra AV implant, of whom 31 remained in VDD mode at some visit throughout the follow-up, and 26 remained in VDD mode at 3 months follow-up. Device reprogramming of nominal parameters was needed in all patients at follow-up (table). The automatic A3 window end was disabled, and a fixed and short value was set in 100% of patients. Lower HR was set to 40 bpm in 88.5% (n=23) of patients. Auto A4 threshold and auto A3 threshold were modified in 6 and 3 patients respectively and vector was changed in 3 patients. An ambulatory 24-h Holter monitor was performed 112.8±37.5 days after the implant in the 26 patients who remained in VDD. A comparison between nominal parameters and programming at ambulatory 24-h Holter monitoring is displayed in the table. Total ECG recorded time was 550.8 hours and 2,291,953 cardiac cycles were analyzed. Average ambulatory AVS was 87.3±6.3% (median: 87.6%) and 20 out of 26 patients showed an AVS≥85% of cardiac cycles. AVS across the different heart rate ranges was good and remained ≥85% until 90 bpm (figure) with a substantial drop only with HR over 110 bpm. Conclusions High ambulatory AVS in outpatients with leadless pacemakers can be feasible, although may require manual reprogramming of atrial sensing parameters, especially the A3 window end setting.

Cardiological Findings of Babies Born to Mothers with Connective Tissue Disease

Objective: Cardiac conduction system is affected and heart blocks can be seen in newborns whose mothers have connective tissue disease, especially with systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). Anti-SS-A (Ro), anti-SS-B (La) antibodies in the mother's circulation are responsible for this situation. In this study, it was aimed to evaluate the clinical features and long-term follow-up results of babies born to mothers with connective tissue disease in our hospital. Materials and methods: Patients who were hospitalized in the neonatal intensive care unit between January 2001 and January 2016 due to the diagnosis of SLE, SS or connective tissue disease in their mothers were retrospectively screened, and their demographic and clinical characteristics and electrocardiographic findings were recorded. Results: A total of 49 babies from 48 mothers were included in the study. Mean age of mothers at birth was 30.8±5.0 years (28-41), mean gestational week of patients was 35.8±2.5 weeks (28-41), mean birth weight was 2614±680 g (730-3810 g). Ten newborns (20.4%) had 3rd degree atrioventricular (AV) block, and 1 baby had 1st degree AV block. Permanent pacemaker was implanted in five patients in the neonatal period, two of these patients died in the neonatal period. A pacemaker was inserted in a patient who was followed up with AV block in the 6th month. One baby who had no cardiac conduction problem died due to reasons related to prematurity. The mean follow-up period of 46 living babies was 4.6±3.1 (1.2-10.75) years, and the follow-up period of the patients with complete AV block and without a pacemaker was 5.6±2 years. Conclusion: Complete AV block in the neonatal period is a serious cardiac problem that requires rapid intervention. Expectant mothers with known connective tissue disease should be followed in tertiary care centers and the fetus should be followed closely. It is possible for newborns in need to return to their normal lives by inserting pacemakers.

A 3rd degree atrioventricular block revealing hypothyroidism: a case report

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Echocardiographic indicators of anthracycline cardiotoxicity in breast cancer patients with normal left ventricular ejection fraction: Experience of the first cardio-oncology unit in Morocco

Anthracycline is a mainstay in the treatment of many cancers, especially breast cancer. Anthracyclines are known for their significant cardiotoxic potential. Although the cardiotoxicity induced by anthracyclines is dose-dependent and often irreversible, it can occur very early at the start of treatment and sometimes even very late after several years from the end of treatment. The aim of this study was to assess whether echocardiographic measurements of LV function, in the case of normal LVEF, predict the development of anthracycline cardiotoxicity in patients followed for breast cancer. We conducted a longitudinal study of 2329 cancer patients including 2284 female breast cancer survivors, recruited from the cardio-oncology unit in Casablanca, who were diagnosed with primary invasive breast cancer between January 2017 and April 2022. All patients underwent pre-, per- and post-chemotherapy echocardiography. LV volumes, LVEF, MAPSE, S’LV, maximum longitudinal strain were measured. Of 2284 patients, 64% had normal resting LVEF. Mean LVEF was 56 ± 5%, global longitudinal strain (GLS) was −17.4 ± 2.2%, and LV end diastolic volume (LVEDV) was 108 ± 17 mL, MAPSE was 17 ± 5 mm and S’VG was 9+/4 cm/s. 12% percent presented with cardiotoxicity: heart failure with alteration of LVEF by more than 15% (CI) in 163 patients, 67% of whom had an altered S’LV < 8 cm/s) and an altered SGL (>−18%), arterial hypertension in 58 patients, 17 cases of pericardial effusions, 15 cases of arrhythmias, 6 cases of 3rd degree atrioventricular block and 3 cases of right ventricular dysfunction. Age, diabetes, obesity, GLS and LVEDV were all predictive of MACE (P = 0.028, 0.017, 0.041, 0.038 and 0.014 respectively). In patients treated with anthracyclines with normal pre-chemotherapy LVEF, longitudinal function (MAPSE AND S’LV) and baseline GLS predict the development of cardiotoxicity. This helps us to develop algorithms for close monitoring in this type of patient.

Powikłania wymiany stymulatora serca — opis przypadku pacjentki z zakrzepicą żył głębokich kończyny górnej

Deep venous thrombosis of the upper extremity (UEDVT) after pacemaker implantation (PM) is often an underestimated problem, but should be considered as a potential complication, because the number of implanting PM is increasing every year. This case report presents a history of a 57-years old woman with a pacemaker implanted in 1996 due to the 3rd-degree atrioventricular block. The patient was admitted to the hospital for the replacement of the stimulating system. The procedure was complicated by hemorrhage from the pocket of the device and in the postoperative period — the left upper extremity deep vein thrombosis.

Plasmapheresis in Neonatal Lupus

About 2% of mothers with Sjögren’s syndrome and about 1% of mothers with systemic lupus erythematosus deliver a baby with a congenital heart block (CHB). This is thought to be as a result of the maternal autoantibodies that cross the placenta and cause congenital lupus in the fetus/neonate. Among patients with a 2nd or 3rd degree atrioventricular block, the mortality rate in the neonatal period is about 10%, and most neonates who survive require a pacemaker into adulthood. Despite the compelling mortality and morbidity, the data on the optimal preventive treatments are meager and not well-established. In addition to pharmaceutical therapy, one potentially effective therapy is plasmapheresis. Plasmapheresis is safe in pregnancy, well tolerated, and is effective in removing the offending substances in the serum which may cause disease. We review this literature, in order to educate the reader and to motivate interest in studying this condition in the future.

Predictors of pacemaker implantation in patients with myocardial infarction and heart block

The aim of the study was to identify predictors of early and delayed pacemaker (PM) implantation in patients with myocardial infarction (MI) and heart block, allowing the development of models for predicting the feasibility of its implantation.Methods. A randomized selection method was used to form a cohort of patients with MI complicated by cardiac conduction disorders. The first (control) group included 72 patients who did not have a PM implanted, the second (n=46) and third (n=68) groups consisted of patients with MI, having, respectively, indications for early (in the acute period of MI) and delayed (average after 3 years) PM implantation. All patients underwent endovascular revascularization of the infarct-dependent artery during hospitalization. Demographic, clinical, and morphological predictors of PM implantation in patients of the second and third groups were evaluated in comparison with the control group. Multiple logistic regression was used to identify factors associated with the need for PM implantation in the short term (hospital period) and in the long-term period.Results. Factors that determine the expediency of a permanent PM in the acute period of MI at the hospital stage, delayed pacemaker implantation 3.2±1.9 years after myocardial infarction, as well as predictors that do not require a permanent PM throughout the entire observation period, were identified. The main factors that require permanent PM implantation in the acute period were identified: 3rd degree atrioventricular (AV) block in NSTEMI, GRACE score 96 or higher, development of 3rd degree AV block in MI of any localization except postero-inferior. Predictors for the need for PM implantation after 3.2±1.9 years (delayed period) were STEMI of anterior localization; at the same time, age had an inversely proportional relationship in predicting the fact of permanent pacing. The factors that determine the need for PM implantation are the presence of anterior MI, the multiple coronary artery lesions.Conclusion. In the acute (hospital) period of NSTEMI, PM implantation is indicated at a high risk of adverse cardiovascular complications (GRACE scale of 96 points and above), in the presence of the 3rd degree AV block in any MI localization, except for the inferior one. Indications for permanent pacing 3.2±1.9 years after an acute coronary event are STEMI of anterior localization and multiple coronary artery lesions.

Abstract 12645: Role of Viral Rna-Triggered Innate Immune Activation on Cardiac Arrhythmias Associated With Covid-19

Background: The COVID-19 pandemic has highlighted how little is known about how double stranded RNA (dsRNA) viruses like the SARS-CoV-2 impact cardiac physiology acutely and long-term. While it is unclear if the cardiac effects are direct or indirect, adverse effects in patients are common, including cardiac inflammation, electrophysiological changes in QT interval, atrial fibrillation, bradyarrhythmia, and ventricular tachycardia. Mechanisms underlying these COVID-19-associated arrhythmias are unknown. Methods: We assess the effects of SARS-CoV-2 infection on cardiac electrophysiology and inflammatory pathway activation in a hamster model over a 4-week timespan. We further test if activation of antiviral innate immune responses with a dsRNA mimetic, Poly I:C (PI:C) induces similar effects in uninfected hearts and in human iPSC-derived cardiomyocytes (hiPSC-CMs), examining the determinants of RNAseL activation, interferon (IFN) signaling, and cytokine release in vivo and in vitro. Results: Intranasal SARS-CoV-2 USA-WA1 infection of hamsters caused ECG abnormalities including bradycardia and cardiac conduction defects including sinus pauses, 2 nd and 3 rd degree Atrio-Ventricular block. Bradycardia peaked at 4-5 days after infection. Mean RR interval increased from 182±4ms pre- to 233±6ms post-infection, without significant increases in mock-infected hamsters. In the absence of viral infection, ventricular injection of PI:C induced similar arrhythmias and induction of IFN-stimulated genes. PI:C treatment of hiPSC-CMs induced robust increases in type-I IFN pathway proteins STAT1/pSTAT1, OAS2 (48% increase) and OAS3 (32% increase) and a robust cytokine response. Negative effects on excitation-contraction coupling after 72hr of PI:C treatment, manifested as a 25% reduction in hiPSC-CM Ca 2+ transient peaks. In vitro studies showed increased RNA degradation after PI:C, consistent with activation of the OAS/RNAseL dsRNA sensor pathway. Conclusions: COVID-19 in the hamster model recapitulates a subset of arrhythmias observed in COVID-19 patients. Activation of the viral dsRNA innate immune sensor pathway, even in the absence of active cardiac viral replication, may contribute to SARS-CoV-2-associated cardiac dysfunction.

Type 2 diabetes is associated with higher risk of 3rd degree atrioventricular block: a Danish nationwide registry study

Abstract Background Type 2 diabetes (T2DM) is suggested to affect the function of the cardiomyocytes and electrical pathways which could cause conduction abnormalities and cardiac arrhythmias, such as 3rd degree atrioventricular block. The association of T2DM and 3rd degree atrioventricular block has never been confirmed in large nationwide studies. Purpose To determine the association between T2DM and 3rd degree atrioventricular block. Method This nationwide nested case-control study design included patients older than 18 years, diagnosed with 3rd degree atrioventricular block between 1st of July 1995 and 31st of December 2018. Five controls from the risk set of each case of 3rd degree atrioventricular block were matched on age and sex to fit a Cox regression model with time-dependent exposure (T2DM) and time-dependent covariates and baseline hazard function stratified for age and sex. Subgroup analysis was conducted with Cox models for each subgroup. Results We identified 31.177 cases with 3rd degree atrioventricular block that were matched with 155.885 controls. The mean age was 78 years and 60% were males. Cases had higher prevalence of T2DM (20% vs 7.8%), hypertension (70% vs 43%) myocardial infarction (16% vs 6.6%), and heart failure (21% vs 5.9%) compared to the control group. In a Cox analysis T2DM was significantly associated with a higher rate of 3rd degree atrioventricular block [HR 2.61 (95% CI: 2.54–2.71)]. The association remained in several subgroup analyses of diseases suspected to be associated with 3rd degree atrioventricular block. There was a significant interaction with sex and age groups and comorbidities of interest including hypertension, atrial fibrillation, heart failure and myocardial infarction (Figure 1). Conclusion T2DM is associated with a higher rate of 3rd degree atrioventricular block. The findings were consistent across subgroups. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This work was funded by the independent research foundation Skibsreder Per Henrik, R. og Hustrus Fond

Identifying high risk patients post myocardial infarction with reduced left ventricular function using loop recorders INSPIRE-ELR clinical study

AimsSudden cardiac death (SCD) continues to be a devastating complication amongst survivors of myocardial infarction (MI). Mortality is high in the initial months after MI. The aims of the INSPIRE-ELR study were to assess the proportion of patients with significant arrhythmias early after MI and the association with mortality during 12 months of follow-up. MethodsThe study included 249 patients within 14 days after MI with left ventricular ejection fraction (LVEF) ≤35% at discharge in 11 hospitals in India. Patients received a wearable external loop recorder (ELR) 5 ± 3 days after MI to monitor arrhythmias for 7 days. ResultsPatients were predominantly male (86%) with a mean age of 56 ± 12 years. In 82%, reperfusion had been done and all received standard of care cardiovascular medications at discharge. LVEF was 32.2 ± 3.9%, measured 5.1 ± 3.0 days after MI. Of the 233 patients who completed monitoring (7.1 ± 1.5 days), 81 (35%) experienced significant arrhythmias, including Ventricular Tachycardia/Fibrillation (VT/VF): 10 (4.3%); frequent Premature Ventricular Contractions (PVCs): 65 (28%); Atrial Fibrillation (AF): 8 (3.4%); chronic atrial flutter: 4 (1.7%); 2nd or 3rd degree Atrioventricular (AV) block: 4 (1.7%); and symptomatic bradycardia: 8 (3.4%). In total, 26 patients died. Mortality was higher in patients with clinically significant arrhythmia (at 12 months: 23.6% vs 4.8% with 19 vs 7 deaths, hazard ratio (HR) = 5.5, 95% confidence interval (CI) 2.3 to 13.0, p < 0.0001). Excluding 7 deaths during ELR monitoring, HR = 4.5, p < 0.001. ConclusionELR applied in patients with acute MI and LV dysfunction at the time of discharge identifies patients with high mortality risk.

Effects of Atrioventricular Blocks in Acute Coronary Syndrome: Long-Term Follow-Up.

Arrhythmias are the common, potentially lethal, and treatable complication of acute coronary syndrome (ACS). Arrhythmic findings of ischemic cardiac events are well-known, but long-term results have not been scrutinized. In the study, we aimed to analyze the long-term findings of the atrioventricular block (AVB) in ACS patients. This is a single-center and retrospective study of patients admitted with ACS and AVB. The primary endpoint has combined the outcome of major adverse cardiovascular events and mortality. Seventy-six (89.4%) patients had 3rd-degree AVB. Fifty (58.8%) patients are needed for temporary ventricular pacing and 4 (4.7%) for a permanent pacemaker. Although no cardiac death occurred during the 5-year follow-up period, the in-hospital mortality ratio was 30.6%. Patients with older age and lower systolic blood pressure (SBP) levels had higher mortality rates (respectively, odds ratio [OR] 1.088, [p=0.003], OR 0.912, [p<0.001]). Even in ST-segment elevation myocardial infarction and complete AVB subgroup analyses, mortality rates were associated with SBP and age (respectively, OR: 0.917, [p<0.001], OR: 1.107 [p=0.002]), (respectively, OR: 0.917 [p<0.001], OR: 1.087 [p=0.004]). The study results are associated with a better long-term overall prognosis in patients with ACS with AVB, but lower SBP and older in-hospital follow-up are associated with poor prognosis.

Abstract 9221: Long-Term Risk of New-Onset Arrhythmia in Patients With ST-Segment Elevation Myocardial Infarction According to Revascularization Status

Introduction: Emerging data show that complete revascularization reduces cardiovascular death and recurrent myocardial infarction in ST-segment elevation myocardial infarction (STEMI). The influence of revascularization status on development of arrhythmia in the chronic post-STEMI phase is poorly described. Hypothesis: We hypothesized that incomplete compared with complete revascularization in STEMI is associated with an increased long-term risk of new-onset arrhythmia. Methods: Using unique Danish registries, the risk of new-onset arrhythmia was assessed in STEMI with complete or incomplete revascularization after primary percutaneous coronary intervention (PPCI) at Rigshospitalet University Hospital, Denmark, from 2009-2016. The primary outcome was new-onset arrhythmia defined as a composite of atrial fibrillation/flutter, sinoatrial dysfunction, advanced 2nd- or 3rd-degree atrioventricular block, ventricular tachycardia/fibrillation, cardiac arrest, or pacemaker/ICD implantation, with presentation &gt;7 days post-PPCI. Secondary outcome was all-cause mortality. Results: A total of 5,062 patients (median age: 62.0 years; 76% men) were included, of which 3,985 and 1,077 patients underwent complete and incomplete revascularization, respectively. During a median follow-up of 4.9 years, 580 (15%) patients in the complete and 217 (20%) patients in the incomplete revascularization group were diagnosed with new-onset arrhythmia (Figure 1). Compared with complete revascularization, incomplete revascularization was associated with a higher risk of new-onset arrhythmia (adjusted hazard ratio [HR] 1.3; 95% CI, 1.1-1.5; P=0.004) and higher all-cause mortality (adjusted HR 1.3; 95% CI, 1.0-1.5; P=0.02). Conclusions: Incomplete revascularization in STEMI was associated with an increased long-term risk of new-onset arrhythmia and all-cause mortality compared with complete revascularization.

Implantable loop recorder follow-up

Abstract Introduction Long ambulatory ECG monitoring can be a useful component in the evaluation of the patient with unexplained syncope or syncope with suspected arrhythmic origin, as well as a sensitive tool for detecting asymptomatic spontaneous cardiac arrhythmias or conduction abnormalities in predisposed patients. Purpose To determine the diagnostic cost-effectiveness of the implantable loop recorder (ILR) in the origin of unexplained syncope in our center. Methods A retrospective observational study was carried out in a tertiary center, those patients with an ILR between August 2014 and March 2021 were included. Baseline characteristics of the population and their previous ECG, arrythmias detected during follow-up and pacemaker implant rate were evaluated. Results One hundred twenty-seven patients with a ILR were included (age 67 years, 49.6% males). Most often cause of ILR was unexplained syncope (90.6%) followed by monitoring after TAVI implant (3.9%). Normal LVEF (&amp;gt;50%) was present in 85.6%,and 75.6% had NYHA I functional class. 118 patients (92.9%) presented sinus rhythm at implant time, and 8 (6.3%) presented AF. 12.6% presented first degree atrioventricular (AV) block, 2 patients (1.6%) had presented previously Mobitz Type I AV block and one patient 2:1 block. Left bundle branch block (LBBB) was present in 13.4%,RBBB in 3.1%,LAFB in 9.4%, RBBB+LAFB in 11% and RBBB+LPFB in 2.4%. Median time of follow-up was 21 months. 3rd degree AV block was the most frequent arrhythmia detected (12.1%), followed by &amp;gt;3s pause (8%) and previously unknown AF (2.4%).The patients with syncope who suffered head trauma (33%) presented a higher rate of pacemaker (PCM) implant compared to those without head trauma: 31.6% vs 14.7%. In total,19.8% PCM rate implant during follow-up. No complications ILR related. Conclusion In conclusion, long home ECG monitoring with ILR is a powerful and helpful tool to find out or rule out potentially dangerous arrhythmias as cause of syncope, with no complications in our experience. Funding Acknowledgement Type of funding sources: None. Baseline characteristicsArrhythmias detected during follow-up

Comparing the Visual Perception According to the Performance Using the Eye-Tracking Technology in High-Fidelity Simulation Settings.

Introduction: We used eye-tracking technology to explore the visual perception of clinicians during a high-fidelity simulation scenario. We hypothesized that physicians who were able to successfully manage a critical situation would have a different visual focus compared to those who failed. Methods: A convenience sample of 18 first-year emergency medicine residents were enrolled voluntarily to participate in a high-fidelity scenario involving a patient in shock with a 3rd degree atrioventricular block. Their performance was rated as pass or fail and depended on the proper use of the pacing unit. Participants were wearing pre-calibrated eye-tracking glasses throughout the 9-min scenario and infrared (IR) markers installed in the simulator were used to define various Areas of Interest (AOI). Total View Duration (TVD) and Time to First Fixation (TFF) by the participants were recorded for each AOI and the results were used to produce heat maps. Results: Twelve residents succeeded while six failed the scenario. The TVD for the AOI containing the pacing unit was significantly shorter (median [quartile]) for those who succeeded compared to the ones who failed (42 [31–52] sec vs. 70 [61–90] sec, p = 0.0097). The TFF for the AOI containing the ECG and vital signs monitor was also shorter for the participants who succeeded than for those who failed (22 [6–28] sec vs. 30 [27–77] sec, p = 0.0182). Discussion: There seemed to be a connection between the gaze pattern of residents in a high-fidelity bradycardia simulation and their performance. The participants who succeeded looked at the monitor earlier (diagnosis). They also spent less time fixating the pacing unit, using it promptly to address the bradycardia. This study suggests that eye-tracking technology could be used to explore how visual perception, a key information-gathering element, is tied to decision-making and clinical performance.

Rheumatoid arthritis mimicking infective endocarditis with severe aortic regurgitation and aortic root abscess: a case report.

BackgroundRheumatoid arthritis (RA) may involve the cardiovascular system and can cause significant structural cardiac disease. RA mimicking infective endocarditis (IE) is rarely reported.Case summaryA 46-year-old man with a medical history of seropositive RA attended a planned outpatient visit for infliximab treatment. The pre-infusion examination revealed a pulse of 41 b.p.m. and the following electrocardiogram showed 3rd degree atrioventricular block. A temporary pacemaker was inserted, and subsequent transthoracic and transoesophageal echocardiograms showed severe aortic valve regurgitation with thickened cusps and thus raised suspicion of infective aortic endocarditis with root abscess. The patient underwent surgery with valve and root replacement the next day. What was thought to be IE, proved to be suppurative and granulomatous inflammation with sporadic necrosis and hyaline fibrosis, compatible with a rheumatoid nodule linked to the patient’s RA diagnosis.DiscussionIE is a disease with high mortality and morbidity. In some cases of IE perivalvular cavities develop, most commonly abscesses and/or pseudoaneurysms, which necessitates surgery. Several conditions may mimic IE: for example, malignant and benign tumours, rheumatic diseases, and common age-related valve calcification. In patients with valvular vegetations that are ‘culture-negative’, alternative pathologies should be considered.