bluuebunny/crossref_metadata_2025_split huggingface dataset:
The relationship between left ventricular outflow tract gradient and sudden cardiac death in childhood hypertrophic cardiomyopathy
Authors: Norrish G , Ding T , Field E , O'Mahony C , Elliott P.M , Omar R , Kaski J.P 
Published: November 2020

Abstract

Background
The most common mode of death in childhood hypertrophic cardiomyopathy (HCM) is sudden cardiac death (SCD). Left ventricular outflow tract obstruction (LVOTO) is an established risk factor for SCD in adults with the disease. In contrast, the prognostic implications of LVOTO in childhood disease is unclear, with recent studies suggesting that it may have an inverse relationship with the risk of SCD.

Purpose
The aim of this study was to explore the role of LVOTO and the risk of SCD in childhood HCM.

Methods
A multi-centre, retrospective, longitudinal cohort of 871 children (diagnosed with HCM &lt;16 years of age) was used to explore the relationship between SCD and LVOTO (LVOT gradient ≥30mmHg).

Results
189 patients (23%) had LVOTO, which was mild (30–50mmHg), moderate (50–100mmHg) or severe (&gt;100mmHg) in 58 (6.7%), 98 (11.3%) and 33 (3.8%), respectively. The risk of SCD showed an inverse relation to LVOT gradient severity compared to those with no obstruction: mild HR 1.75 (95% CI 0.89–3.44), moderate HR 1.04 (95% 0.55–1.98), and severe HR 0.7 (0.36–1.35) [figure].On univariable analysis [table] LVOTO was associated with heart failure symptoms (NYHA&gt;1) [p &lt;0.001], maximal wall thickness (MWT) [p &lt;0.001], left atrial (LA) diameter [p &lt;0.001], and future myectomy occurring during follow up [p &lt;0.001]. The inverse relationship observed was not altered by the presence or absence of other traditional risk factors.

Conclusions
LVOTO appears to have a complex relationship with the risk of SCD in childhood HCM, with multiple contributing factors. The pathophysiological mechanisms behind this observation need further exploration, which may be limited by low patient numbers
Cummulative incidence of SCD by LVOTO

Funding Acknowledgement
Type of funding source: Other. Main funding source(s): British Heart Foundation
Clinical aspects of pediatric Brugada syndrome
Authors: Imamura T , Makiyama T , Huang H , Aizawa T , Gao J , Kashiwa A , Wuriyanghai Y , Yamamoto Y , Kohjitani Y , Kato K , Ohno S , Sumitomo N , Horie M 
Published: November 2020

Abstract

Introduction
Brugada syndrome (BrS) is an inherited arrhythmia characterized by a coved-type ST elevation and sudden death, especially in middle-aged males and more common in Asia. Mutations in SCN5A are detected in 15–20% and reported to be associated with poor prognosis. Among children, BrS is rare and the risk factors in pediatric BrS are unknown, especially in Asian population.

Purpose
The purpose of this study is to elucidate the risk factors for fatal arrhythmic events in Japanese pediatric patients with BrS.

Methods
We enrolled 52 Japanese children with BrS younger than 20 years, and performed genetic analysis and collected the clinical information.

Results
The mean age of initial symptoms was 10.7±5.5 years, and the mean follow-up period was 3.9±5.5 years. Ninety percent of patients were probands. No subjective symptom was confirmed in 28 of the patients, but aborted cardiac arrest (ACA) in 4, ventricular tachycardia in 4, ventricular fibrillation in 1, and syncope in 11. We identified mutations in SCN5A in 63%. There was no significant gender difference in ≤10 years, but a significant male predominance appeared in &gt;10 years. And no gender difference was confirmed in the incidence of severe cardiac events in ≤10 years.

Conclusion
No gender difference was confirmed in ≤10 years in this study about Asian children. And being girls did not reduce the risk in ≤10 years. The frequency of SCN5A mutations was higher than adults, but decreased from childhood (68%) to adolescence (59%). In BrS, genetical and environmental factors may be more effective in childhood and adulthood, respectively.

Funding Acknowledgement
Type of funding source: None
Atenolol is not effective in reducing ventricular arrhythmia severity on exercise stress test in patients with catecholaminergic polymorphic ventricular tachycardia
Authors: Peltenburg P , Lieve K.V.V , Van Der Werf C , Wilde A.A.M , Brugada R , Till J , Ackerman M.J , Probst V , Haugaa K , Swan H , Kammeraad J.A.E , Horie M , Sanatani S , Schwartz P , Leenhardt A 
Published: November 2020

Abstract

Patients with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for malignant ventricular arrhythmias during exercise and emotions which may lead to sudden cardiac death. Beta-blockers (BB) are the mainstay of therapy in patients with CPVT, but studies comparing the efficacy of different types of BB are scarce. Our objective was to determine the efficacy of different types of BB in reducing the ventricular arrhythmia (VA) severity on exercise stress test (EST) in patients with CPVT.
Data was derived from the International CPVT Registry, a large retrospective cohort study. We included patients who had an EST before (pre-EST) and after start of BB (post-EST). We divided the cohort into five groups based on the first prescribed BB and compared pre-EST and post-EST.
We included 428 patients (median age 18.5 [11.7–39.6] years, 240 (56.%) female), 155 (36.2%) probands) of whom 38 (8.9%) used atenolol, 131 (30.6%) bisoprolol, 82 (19.2%) metoprolol, 124 (29.0%) nadolol and 53 (12.4%) propranolol. Sex and history of aborted cardiac arrest were similar in all groups. The age at start of BB differed (p&lt;0,001): patients using bisoprolol were oldest (35.0 [15.7–35.3]) while patients using propranolol were youngest (12.3 [8.8–24.9]). Median daily BB dose in mg/kg was: 1.0 [0.8–2.3] for atenolol, 0.06 [0.05–0.10] for bisoprolol, 0.9 [0.6–1.5] for metoprolol, 1.1 [0.9–1.6] for nadolol and 1.5 [1.1–2.8] for propranolol. Resting heart rate on pre-EST and post-EST was similar in all groups. Patients using metoprolol had a significantly higher maximum heart rate post-EST compared to nadolol and propranolol (161±18 vs 136±19 and 130±22 bpm, p=0,002 and p=0,001, respectively). The VA severity decreased significantly after BB (147 (37.9%) (non-sustained) ventricular tachycardia ((NS)VT) and 120 (30.9%) no or isolated ventricular premature beat (iVPB) pre-EST vs 46 (11.4%) (NS)VT and 184 (45.7%) iVPB post-EST, p&lt;0,001). Examining the different groups, the VA severity decreased significantly after BB in all but atenolol (13 (40.6%) (NS)VT and 8 (25.0%) iVPB pre-EST vs 9 (25.0%) (NS)VT and 15 (41.7%) iVPB post-EST, p=0,103).
Based on these results we conclude that all beta-blockers except atenolol are effective in reducing the VA severity on EST in patients with CPVT.

Funding Acknowledgement
Type of funding source: Public grant(s) – EU funding. Main funding source(s): E-Rare Joint Transnational Call for Proposals 2015 “Improving Diagnosis and Treatment of Catecholaminergic Polymorphic Ventricular Tachycardia: Integrating Clinical and Basic Science”
Comparison of electrical characteristics between atrial and ventricular side His-bundle pacing in bradycardia patients
Authors: Liu X , Gu M , Hu Y.R , Hua W , Zhang S 
Published: November 2020

Abstract

Background
His-bundle pacing (HBP) is recognized as the most physiological way of pacing but with less study focused on electrical characteristics in different site.

Purpose
We aimed to evaluate the differences of pacing and echocardiographic parameters between atrial and ventricular side His-bundle pacing.

Methods
Patients who successfully underwent HBP implantation from September 2018 to August 2019 were retrospectively analyzed. All patients were assigned to atrial-side HBP (aHBP) group or ventricular-side HBP (vHBP) group according to the location of the His-bundle pacing lead, which was confirmed by two methods including postoperative echocardiography and visualization of tricuspid valve annulus (TVA). The pacing and echocardiographic parameters were compared between two groups during the procedure and at 3-month follow-up.

Results
A total of 71 bradycardia patients who successfully underwent HBP implantation and confirmed lead position were included. Among them, twenty-seven were assigned to aHBP group and the other 44 were assigned to vHBP group with no significant differences in baseline clinical characteristics between two groups. During the procedure, the proportion of selective HBP was significantly higher (77.8% vs. 11.4%; P&lt;0.01) and the intra-procedural HV intervals was significantly longer (50.85±6.53 ms vs. 42.95±6.02 ms, P&lt;0.01) in aHBP group than in vHBP group. The capture threshold in vHBP group was significantly lower than in aHBP group at implantation (0.92±0.22 V/1.0ms vs. 1.05±0.26 V/1.0ms, P=0.03) and remain significantly difference after 3-month follow-up (0.98±0.23 V/1.0ms vs. 1.15±0.44 V/1.0ms, P=0.03). The R-wave amplitude was significantly higher in vHBP group than in aHBP group at implantation (5.82±2.52 mV vs. 3.74±1.81 mV, P&lt;0.01), and these differences still persisted during follow-up (5.88±2.51 mV vs. 3.67±1.61 mV, P&lt;0.01). During 3-month follow-up, an increase in the capture threshold &gt;1 V/1.0ms was seen in 2 cases in aHBP group while all patients remained stable in vHBP group. One patient developed a pocket hematoma in aHBP group compared to none in vHBP group. None of deterioration of tricuspid regurgitation and other procedure-related complications were observed during 3-month follow-up.

Conclusions
Ventricular side His-bundle pacing can achieve favourable pacing parameters including a lower pacing threshold and a higher R-wave amplitude than atrial side His-bundle pacing, which may be an ideal pacing strategy for patients in need of ventricular pacing.

Funding Acknowledgement
Type of funding source: None
Usefulness of lead delivery catheter system for true right ventricular septal pacing
Authors: Miyajima K , Urushida T , Ito K , Kin F , Okazaki A , Takashima Y , Watanabe T , Kawaguchi Y , Wakabayashi Y , Naruse Y , Maekawa Y 
Published: November 2020

Abstract

Background
Right ventricular (RV) septal pacing is often selected to preserve a more physiologic ventricular activation. But the pacing leads are not always located in true septal wall, rather in hinge or free wall in some cases with the conventional stylet-guided lead implantation. In recent years, new guiding catheter systems has attracted attention as a solution to that problem.

Objective
The aim of this study is to investigate that true ventricular sepal pacing can be achieved by use of the new guiding catheter system for pacing lead.

Methods
We enrolled 198 patients who underwent RV septal lead implantation and computed tomography (CT) after pacemaker implantation. 16 cases were used delivery catheter (Delivery), and 182 cases were used stylet for targeting ventricular septum (Conventional). We analyzed the lead locations with CT, and evaluated capture thresholds, R-wave amplitudes, lead impedances and 12-lead electrocardiogram findings one month after implantation.

Results
All cases of delivery catheter group had true septal lead positions (Delivery; 100% vs Conventional; 44%, p&lt;0.01). Capture thresholds and lead impedances had not significant differences between between two groups (0.65±0.15V vs 0.60±0.15V, p=0.21, 570±95Ω vs 595±107Ω, p=0.39, respectively). R-wave amplitudes were significantly higher in delivery catheter group (13.0±4.8mV vs 10±4.6mV, p&lt;0.01). Paced QRS durations were shorter in delivery catheter group (128±16ms vs 150±21ms, p&lt;0.01).

Conclusions
The delivery catheter system designated for pacing lead can contribute to select the true ventricular septal sites and to attain the more physiologic ventricular activation.

Funding Acknowledgement
Type of funding source: None
Leadless pacemaker implant in patients with a history of open heart surgery: experience with the Micra transcatheter pacemaker
Authors: Garweg C , Iacopino S , El-Chami M.F , Veltmann C , Clementy N , Grubman E , Johansen J.B , Knops R , Schalij M.J , Piccini J.P , Soejima K , Stromberg K , Fagan D.H , Roberts P.R 
Published: November 2020

Abstract

Background
The Micra transcatheter pacemaker has demonstrated a favorable safety and efficacy profile relative to transvenous pacing. Patients with a history of open heart surgery have a higher risk of complications with transvenous pacemakers during follow-up. The experience with leadless pacemakers among a large cohort of patients with a history of open heart surgery has not been reported.

Objective
To report outcomes in patients with a history of open heart surgery undergoing Micra implant.

Methods
Patients undergoing Micra implant from the Micra Transcatheter Pacing Post-Approval Registry (PAR) were included in the analysis. Baseline and procedural characteristics, major complications, and electrical performance were compared among patients with vs. without history of cardiac surgery.

Results
A total of 331 out of 1815 (18.2%) patients had a history of open heart surgery, underwent Micra implant, and were followed for 19.4±10.4 months. The mean age was 74.6±13.5 years, 40% were female. The most common cardiac surgery was aortic valve surgery (71%) followed by mitral valve surgery (39%). Patients with prior open-heart surgery were more likely to have contraindications to transvenous pacing, were more likely to be on oral anticoagulants, and had more co-morbidities including atrial fibrillation, heart failure, and coronary artery disease (all p&lt;0.005). Implantation was successful in 327 of 331 patients (98.8%) with a median procedure time of 29 minutes. Mean pacing capture thresholds (PCTs) at implant were 0.66±0.51V and remained stable through follow-up. There were 11 major complications in 10 cardiac surgery patients, with no device or procedure-related infections reported. The major complication rate was 3.1% (Figure) and was not significantly different than that of patients without a history of open heart surgery (HR: 0.85, P=0.640). There was 1 cardiac perforation (with no intervention required) in the open heart surgery group (0.3%) and there were 14 cardiac perforations (0.94%, P=0.332) in the non-open heart surgery group of which 10 required intervention.

Conclusion
The Micra transcatheter pacemaker can be safely implanted in patients with a history of open heart surgery, with a similar long-term safety profile to patients without a history of open heart surgery. Importantly, there were no device-related infections reported in either group.
Risk of Major Complication

Funding Acknowledgement
Type of funding source: Private company. Main funding source(s): Medtronic, Inc.
A randomised, double-blind, controlled trial on patients undergoing cardiac implantable electronic device implantation with local anaesthesia and sedation with and without pectoral nerve block
Authors: Wang Y , Chandran R , Woon K.L , Chang S.S , Quek H.Y , Singh P.A , Tan P.T , Yeo C , Wong K , Tong K.L , Tan V.H 
Published: November 2020

Abstract

Background
Implantation of cardiac implantable electronic devices (CIED) are generally carried out with local anaesthesia (LA) and sedation. However, peri-procedural hypoxaemia and hypotension are well recognised complications of this technique primarily due to sedation effect. The pectoral nerves block (PECs) targets the lateral and median pectoral nerves at interfascial plane between pectoralis major and minor muscles. This technique potentially lower sedation usage and therefore lower sedation-related complications. There is, however, no randomised study to date comparing CIED procedure with and without PECs block.

Methods
We randomly assigned 64 patients undergoing CIED implantation procedure with LA (subcutaneous lignocaine 1%) and sedation (intermittent bolus of intravenous midazolam and fentanyl according to pain score) with (32 patients) and without (32 patients) PECs. Those received PECs with be given 10 mls of 0.25% ropivacaine. Primary endpoint was total dose of sedation used. Secondary endpoints were perioperative incidence of hypoxia, hypotension and hypopnea, perioperative pain scores, proceduralists' and patients' satisfaction scores.

Results
Overall, majority were male (64.1%), mean age of 67.9±10.7 years, mean BMI of 25.7±5.5 kg/m2 and mean lignocaine 1% dosage was 15.3±3.1mL. Compare to those with and without PECs, there was no significant difference in baseline characteristics. The mean fentanyl [25.3±25.0 mcg (95% CI: 16.3–34.3) vs 32.2±26.7 mcg (95% CI: 22.6–41.8), p=0.29] and midazolam dosage [0.7±0.7mg (95% CI: 0.4–0.9) vs 0.8±0.8 (95% CI: 0.6±1.1), p=0.36] were trended lower in PECs compared to without PECs. PECs group had lower pain score at recovery (OR: 1.7, 95% CI: 0.38–7.93, p=0.48). Proceduralists' and patients' satisfaction score were trended higher in PECs compare to non-PECs group. There was no hypoxia, hypotension or hypopnea in both groups.

Conclusion
Patients underwent CIEDs implantation procedure with PECs received lower sedation dosage and lower periprocedure pain score as compare to non-PECs group. Satisfaction score for both proceduralists and patients were trended higher in PECs group compare to non-PECs group.

Funding Acknowledgement
Type of funding source: Public hospital(s). Main funding source(s): Changi General Hospital Research Grant
Pacemakers capable of monitoring sleep-disordered breathing: impact on sleep apnea detection in real life
Authors: Bidegain N , Garcia R , Degand B , Christiaens L , Bouleti C , Le Gal F , Tavernier M 
Published: November 2020

Abstract

Background
Pacemaker recipients are at high-risk of sleep apnea (SA). New generation of pacemakers allow day by day, sleep-disordered breathing (SDB) monitoring. These devices measure variations in thoracic impedance and can detect apnea and hypopnea.

Purpose
The aim was To compare the rate of SA detection in patients implanted with and without pacemaker capable of monitoring (SDB).

Methods
This retrospective study included all consecutive patients implanted with a pacemaker between 2013 and 2016 at Poitiers university hospital. Pacemaker recipients allowing SDB monitoring (SDB monitoring group) and pacemaker recipients not allowing SDB monitoring (control group) were compared in terms of SA diagnosis, continuous positive airway pressure (CPAP) therapy initiation, newly AF discovered and stroke occurrence.

Results
Among the 1442 patients included (mean age 79 years, 39% of women, BMI = 27 kg/m2). 653 were in the SDB monitoring group and 789 in the control group. The 2 groups were not different in terms of age, body mass index, cardiovascular risk factor, cardiac function, and medication. Indication for cardiac pacing was atrioventricular block and sinus dysfunction in 56% and 23% of patients respectively. Mean follow-up was 24.7 months. 40 patients (7.5%) have been diagnosed with SA in the SDB monitoring group and 18 (2.7%) in the control group (p&lt;0.001). CPAP therapy was initiated in 33 (5%) patients in SDB monitoring group and in 16 (2%) patients for the control group (p=0.01). The rate of newly diagnosed AF was 15% in SDB monitoring and 7% in control group (p&lt;0.001). The incidence of stroke was 16 (2.4%) in the SDB monitoring group and 18 (3.4%) in the control group (P=0.45).

Conclusion
In real life conditions, pacemakers capable of monitoring SDB improve the diagnosis of SA and CPAP therapy rate.
Monitoring of sleep apnea after at least

Funding Acknowledgement
Type of funding source: None
Valsartan improves left ventricle contractility and prevents its remodeling in patients with dual chamber pacemaker
Authors: Tomasik A , Radzik E , Pigon K , Banasik G , Jachec W , Romuk E , Birkner E , Kawecki D , Wojciechowska C , Kalarus Z , Gasior M , Nowalany-Kozielska E 
Published: November 2020

Abstract

Introduction
Permanent right ventricle pacing leads to left ventricle dyssynchrony, systolic dysfunction, remodeling, and symptomatic heart failure in the long run. Valsartan is well known for its preventive anti-remodeling function in the post infarction heart remodeling.

Objectives
To assess the effect of valsartan on left ventricle contractility, measured as global longitudinal stain, and its remodeling in patients with second and third degree atrioventricular block with first-time implantation of dual chamber pacemaker.

Methods
This was a randomized, double-blind, placebo controlled single center study. One hundred eligible patients were assigned in a 1:1:1 fashion to receive placebo, valsartan 80mg or 160mg once daily, respectively. Echocardiographic assessment of left ventricle geometry, its systolic and diastolic function was performed at baseline and at twelve months. Global longitudinal strain (GLS) was measured off-line with EchoPac software. One patient from placebo group suffered stroke. We present the baseline date for 100 enrolled patients and follow-up data for 88 patients who have completed the study. Data in valsartan arms are pooled in one group.

Results
Results are presented in table. Data are presented as mean and standard deviation.
Valsartan alleviates diastolic dysfunction, left ventricle dilation and protects from loss of systolic function.

Conclusion
Valsartan has protective effect of left ventricle contractile function and remodeling. It may be useful in prevention of pacing induced heart failure. (ClinicalTrials Identifier NCT01805804)

Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): Medical University of Silesia
The back-up lead in his bundle pacing: evolution over the years
Authors: Zanon F , Marcantoni L , Pastore G , Baracca E , Picariello C , Lanza D , Maddalozzo A , Roncon L 
Published: November 2020

Abstract

Background
His bundle pacing (HBP) can be affected by high thresholds and low sensing. Thus, in selected patients including a back-up lead is advisable.

Objective
Single-centre retrospective analysis of a large HBP experience, focusing on the back-up lead utilization over the years.

Methods
677 pts (76±8 years; 433 males) were implanted with HBP from 2004 to 2019 July. The pts received S-HBP (67%) or NS-HBP by the 3830 lead. The pacing indications were AV block 54%, sinus node disease 17%, slow atrial fibrillation 23%, heart failure 6%. Ischemic cardiopathy was found in 26%; hypertension in 83%, diabetes in28% pts. Baseline QRS duration was 123±32 ms and EF 56±12%.

Results
266 (39%) pts received the back-up lead. In sinus rhythm we implanted 3-chamber PM (His lead:LV port; VV delay 80 ms: His pulses and apical pacing during the refractory period). 30 pts (11%) received a particular type of 3-chamber PM which provides back-up pacing only if His capture fails, thus saving energy. In atrial fibrillation 2-chamber PM was implanted (His lead: atrial port, DVI). We recorded a significant decrease of back-up lead use over the years, strictly related to operators/centre experience (&gt;70% during the first years, nearly 10% during the last year). The C315 fixed curve sheath, strongly contributed to the rapid reduction of back-up lead use thanks to better lead fixation and stability.

Conclusion
The back-up lead utilization is progressively decreasing. It is strictly related to the operator/centre experience. The presence of the back-up lead could strengthen the Hisian pacing reliability, potentially impacting pacing indication even in advanced conduction disturbances and saving device longevity.

Funding Acknowledgement
Type of funding source: None