bluuebunny/crossref_metadata_2025_split huggingface dataset:
Utilization of implantable cardiac monitors in detecting type 1 patterns in brugada syndrome
Authors: Dinatale A , Crocamo A , Bearzot L , Gonzi G , Guidorossi A , Giacopelli D , Bassini M , Grassini D , Niccoli G , Ardissino D , Notarangelo M F 
Published: May 2024

Abstract

Introduction
In individuals with Brugada syndrome, the presence of the type 1 pattern (BP1) is linked to an elevated risk of severe arrhythmias. However, the identification and measurement of BP1 can be challenging due to its intermittent nature. Implantable cardiac monitors (ICMs) provide extended continuous monitoring, potentially overcoming the limitations of intermittent ambulatory ECG monitoring in detecting spontaneous BP1. Nevertheless, their specific application for this purpose remains unevaluated.

Methods
From November 2022 to September 2023, all patients presenting with pharmacologically induced BP1 were enrolled at our centre. An ICM was surgically placed in the left second intercostal space at a 45° angle, enabling readings with a morphology similar to the right precordial ECG leads during ajmaline testing (AT). Patients were remotely monitored, and in addition to routine automatic transmissions, each patient was provided with a remote control to transmit in case of fever or symptomatic events. Transmissions were scrutinized to detect: 1) ST-segment elevation; 2) ventricular arrhythmias; 3) burden of ventricular extrasystoles (PVC). A reading was classified as positive for BP1 if it bore a similar morphology to that recorded during AT. The frequency of BP1-positive transmissions was evaluated across four hourly intervals.

Results
The ICM was successfully implanted in 21 patients (male-to-female ratio 1.62:1, mean age 43.9±13.1 years). Over an average follow-up of 168±70.6 days, a total of 7818 transmissions were received, evenly spread across hourly intervals (minimum of 1296 transmissions per interval). Among these, 173 transmissions were identified as BP1 positive (2.2%), originating from 6 patients (28.6% of the total, all newly diagnosed with spontaneous BP1). The median duration between implantation and the diagnosis of spontaneous BP1 was 16.5 days (range 2-23). The median number of days with at least one positive transmission was 30.2 (range 13.4-73.9). The evening period (6 pm to midnight) displayed a significantly higher rate of positive transmissions compared to the morning (p=0.04) and afternoon (p=0.01); however, not in contrast to the nighttime (p=0.8). No sustained ventricular arrhythmias were observed, and there were no significant differences in PVC burden among patients.

Conclusions
The utilization of ICM for continuous monitoring in patients with pharmacologically induced BP1 led to the identification of spontaneous BP1 patterns in almost 30% of cases during an approximately 6-month follow-up. Evening and nighttime periods exhibited the highest incidence of BP1. This methodology shows promise in quantifying BP1 incidence and could serve as a tool for stratifying arrhythmic risk in individuals with Brugada syndrome.
Diagnostic accuracy of smartwatches for automated atrial fibrillation detection over time: insights from the basel wearable study
Authors: Isenegger C , Mannhart D , Weidlich S , Arnet R , Du Fay De Lavallaz J , Krisai P , Knecht S , Kuehne M , Sticherling C , Badertscher P 
Published: May 2024

Abstract

Background
The first smart-watch (SW) able to record a single lead ECG (SL-ECG) with automated atrial fibrillation (AF) detection algorithm was introduced 2018. Multiple other manufacturers followed. While manufacturers claim to continuously improve their devices’ algorithm, little is known about the impact on diagnostic accuracy on AF detection over time in a real-world cohort of patients.

Purpose
To assess if the diagnostic accuracy of algorithm-based AF detection of 5 smart devices has improved over time.

Methods
In this prospective study, consecutive patients undergoing electrophysiological procedures in a tertiary referral center were included between April 2021 to May 2023. Each participant received a 12-lead ECG and 5 SL-ECGs with different smart devices (AliveCor KardiaMobile, Apple Watch 6, Fitbit Sense, Samsung Galaxy Watch 3 and Withings ScanWatch). All SW were continuously updated for newest software or firmware as recommend by the manufacturers. The SW rhythm classification was compared to manual cardiologist-based interpretation of SL-ECGs. The change in number of inconclusive SL-ECGs by manufacturer’s algorithm were investigated over time via Cochran-Armitage test for trend and illustrated over time via logistic regression.

Results
247 participants were included (30% female, mean age 66.3 [IQR: 57-74] years) resulting in a total of 1’235 SL-ECGs. Among these, 202 SL-ECGs (16%) were labeled as inconclusive by at least one smart-device. Inconclusive rates for individual SW ranged from 15% to 19%. When comparing the first and last quintile of patients in the study period, the inconclusive rates for the KardiaMobile were 14% vs. 6%, for the Apple Watch 14% vs. 6%, for the Fitbit Sense 20% vs. 14%, for the Samsung Galaxy 18% vs. 10% and for the Withings ScanWatch 22% vs. 14%, respectively. When assessed continuously over time, we observed a trend towards fewer inconclusive tracings, without reaching statistical significance (Figure 1).

Conclusion
Over 26 months, inconclusive tracings of 5 SW didn’t significantly decrease despite frequent software updates in a real-world patient cohort. Larger, long-term cohorts are needed to assess if automated AF detection has significantly improved over time.Figure 1
The electrical substrate of vectorcardiographic QRS area in cardiac resynchronization therapy: insights from ECG-imaging
Authors: Nguyen U , Smits K , Cluitmans M , Rijks J , Van Stipdonk T , Prinzen F W , Vernooy K 
Published: May 2024

Abstract

Background
The QRS area shows promise as a vectorcardiographic (VCG) marker for electrical dyssynchrony in patient selection for cardiac resynchronization therapy (CRT). Nevertheless, little information is known about the underlying cardiac electrical substrate it may reflect.

Purpose
The aim of this study was to compare the VCG QRS area with measures of cardiac electrical dyssynchrony derived from electrocardiographic imaging (ECG-imaging).

Methods
QRS area from the synthesized VCG (Kors transformation matrix from the 12-lead ECG) was computed for 27 patients who underwent ECG-imaging (11 patients with no history of structural heart disease and 16 consecutive CRT patients). ECG-imaging measures for electrical dyssynchrony analyzed were: ventricular electrical uncoupling (VEU) computed as the difference between the average LV and RV activation times from ECG-imaging, standard deviation of activation times from the left ventricle (LV SDAT, and the maximal activation (Max AT). Pearson correlation analyses between VCG QRS area and ECG-imaging measures of dyssynchrony were carried out for the entire cohort and for patients with a wide-QRS only.

Results
ECG-imaging measures of dyssynchrony compared with QRS area in 11 patients with no structural heart disease with narrow-QRS (blue) and 16 candidates for CRT with heart failure (HF) and predominantly wide-QRS (LBBB [n=6], IVCD [n=8], RVpaced [n=1], and nQRS-HF [n=1]) are provided in Figure 1. QRS area were associated with all ECG-imaging measures of dyssynchrony. However, sub-analysis in only the wide-QRS patients revealed that QRS area exhibited the strongest association with VEU.

Conclusion
Vectorcardiographic QRS area is associated with cardiac electrical dyssynchrony on ECG-imaging, exhibiting a particularly strong association with ventricular electrical uncoupling.
Useful aid or futile hassle - continuous rhythm monitoring following acute myocardial infarction
Authors: Hamacher L , Wessely E , Jost J , Rohla M , Panzer B , Kaufmann C , Pogran E , Burger A , Ahmed A , Freynhofer M , El Kilany N , Tinhofer F , Huber K , Zweiker D 
Published: May 2024

Abstract

Background
Patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) face an increased risk of cardiac events, including arrhythmias. Current guidelines therefore recommend ECG monitoring for at least 24 hours after AMI in patients with ST segment elevation myocardial infarction (STEMI) and high-risk non-ST segment elevation myocardial infarction (NSTEMI). However, in the last decades medical treatment of AMI has been substantially improved, limiting the risk of arrhythmias post-PCI. Furthermore, continuous ECG monitoring puts additional strain on healthcare personnel during an international healthcare crisis.

Purpose
To evaluate the contemporary burden of ventricular arrhythmias (VA) in AMI patients post-PCI.

Methods
This is a retrospective analysis of consecutive patients undergoing PCI for AMI between 2016 and 2020 at a secondary care centre. We defined the primary endpoint as any VA requiring intervention (electric cardioversion or pharmacologic treatment) after PCI. Baseline characteristics and outcome were compared in patients with NSTEMI vs. STEMI.

Results
A total of 931 patients were included in the analysis, with a mean age of 65 years and 28.6% were female. Patients with NSTEMI (47.3%) were older (median 66 vs. 63 years) and had significantly more comorbidities: hypertension (67.5% vs. 52.1 %), diabetes mellitus (25.4% vs. 15.8%), chronic obstructive pulmonary disease (11.5% vs. 6.7%), and peripheral arterial disease (11.4% vs. 5.3%, p&lt;0.05 for all). VAs requiring intervention occurred in 3.6% vs. 7.1% (p = 0.017) before PCI and in 0% vs. 2.2% (p &lt; 0.001) during PCI in NSTEMI vs. STEMI patients. After PCI the primary endpoint occurred in no NSTEMI patient and in 1.6% of patients with STEMI (p = 0.004).

Discussion
In a cohort of contemporary AMI patients, ventricular arrhythmias occurred rarely and significantly less often in NSTEMI patients compared to STEMI patients. Due to the low risk of VAs in patients with NSTEMI after PCI, the need for post-procedural rhythm monitoring in NSTEMI patients may be questioned. The identification of predictors for VA after AMI should be subject for future trials.
Atrial pace mapping using intracardiac pattern matching: feasibility and accuracy
Authors: Willert S , Demmig T , Maslova V , Zaman A , Popera J , Nicholson L , Sprenger L , Kleinhans L , Jahn O , Frank D , Lyan E 
Published: May 2024

Abstract

Introduction
Pace mapping of atrial arrhythmia is a method to localize the origin of usually focal arrhythmias that are unstable or not persisting during EP-study and, therefore not eligible for LAT-Mapping. The technique applies pattern matching of p-waves from surface-electrocardiogram (sEKG) as well as intracardiac signals during atrial tachycardia and pacing from the site of suspected origin. The CARTO® 3 system Version 7.2 applies an automated algorithm for intracardiac pace mapping (ICPM) using the unipolar signal of the reference electrode, usually located in the coronary sinus.

Methods
We examined 12 consecutive patients undergoing RF pulmonary vein isolation (PVI). We performed local pacing at the anterior and posterior wall of the left atrium (LA) and the posterior and lateral wall of the right atrium (RA). The first pacing point was defined as the reference pacing site (RPS). The ICPM algorithm was applied to calculate the similarity of the IC pattern of the RPS to the IC pattern across various distances. The maps, including mesh, point locations and IC pattern similarity of each point, were exported for further analysis in the Python environment. The areas were calculated for the 5% similarity strata.

Results
The study assessed areas with a 95% or higher pattern similarity in different atrial regions, revealing notable differences in pattern similarity. The median area of pattern similarity was 1.48 cm² (IQR: 0.76 - 2.01 cm²) in the LA posterior, 0.62 cm² (IQR: 0.15 - 1.06 cm²) in the LA anterior, 0.60 cm² (IQR: 0.38 - 1.19 cm²) in the RA posterior, and 5.68 cm² (IQR: 2.89 - 11.1 cm²) in the RA lateral wall. Significant differences were found between the posterior and anterior walls of the LA and the RA lateral wall, as well as between the RA posterior and RA lateral wall, indicating variability in intracardiac pattern matching accuracy. Patterns below 2 cm² are acceptable for catheter ablation. An outlier was noted in the RA posterior region.

Conclusion
The intracardiac pattern matching for atrial arrhythmias employing the CARTO-ICPM algorithm is feasible with acceptable accuracy except for the lateral regions of the right atrium. This might be explained by the larger distance to the referent catheter in the coronary sinus and the preferred conduction direction in the crista terminalis. Enhancing localization accuracy may necessitate the adjunctive use of surface ECG-pace mapping or the deployment of an additional multipolar intracardiac reference catheter in the lateral RA.A: IC Pattern, B: Box plots similarity
Risk Assessment in Patients with Symptomatic and Asymptomatic Preexcitation (RASAP)
Authors: Saygi S 
Published: May 2024

Abstract

Background
Controversy remains as to whether exercise stress test (EST) is sufficient for risk evaluation in patients with preexcitation.

Purpose
This study aims to clarify the usefulness of EST in risk stratification in both asymptomatic and symptomatic patients, presenting with preexcitation.

Methods
This prospective study includes consecutive asymptomatic and symptomatic patients with preexcitation, referred for risk assessment. All participants performed an incremental EST (bicycle), prior to an electrophysiology study (EPS). Primary data from the EST included loss of preexcitation during exercise and from EPS included measurement of accessory pathway effective refractory period (APERP), shortest preexcited RR interval (SPERRI), and inducible arrythmia with use of a beta-adrenergic receptor agonist if deemed necessary.

Results
One hundred and sixty-four patients (59 asymptomatic, 105 symptomatic) completed an EST and EPS. Forty-five patients (27%) demonstrated low-risk findings on EST, of which 19 were asymptomatic and 26 were symptomatic. Six patients with low-risk EST findings had SPERRI/APERP≤250 ms at EPS, two of them were asymptomatic. The sensitivity, specificity, positive and negative predictive value (PPV, NPV) and accuracy of low-risk EST for excluding patients with SPERRI/APERP≤250 ms were 29%, 91%, 80%, 48%, and 55% respectively. The number of patients with inducible arrhythmia at EPS was similar in the asymptomatic 36 (69%) and in the symptomatic 73 (61%) group.

Conclusions
Sudden loss of preexcitation during EST has a low sensitivity and low NPV in excluding high-risk APs. EPS with use of isoproterenol should be considered to accurately assess the risk of patients with preexcitation regardless of symptoms.Figure
Localization of ganglionated plexi by high density mapping: an atropine-response analysis
Authors: Giomi A , Paoletti Perini A , Bernardini A , Padeletti M , Signorini U , Zaccaria C , Ciliberti D , Milli M 
Published: May 2024

Abstract

Introduction
Growing interest has emerged around cardiac autonomic nervous system driven by ablation approaches for the treatment of neurally-mediated syncope (NMS). Ganglionated-plexi (GPs) located in the epicardial fat pads are the main target of ablative therapies, but little is known about the finest method to track their location from the endocardium. Most current techniques rely on empirical research of signal fragmentation and/or vagal response at anatomical landmarks. A poor accuracy in targeting GPs may lead to the risk of incomplete or over-extensive ablation.

Purpose
We analyzed the atrial electrograms (EGMs) in healty subjects and their response to atropine to describe physiological fragmentation and the relationship with vagal output.

Methods
Study partecipants were selected from young patients without structural heart desease who underwent electrophysiological study (EPS) for standard indications. High-density mapping of right atrium was performed before and after administration of 2 mg atropine at the end of the planned procedure. Offline analyses were performed comparing the two maps of each patient focusing on the fragmentation of the atrial EGMs.

Results
The study cohort comprised 10 patients (mean age of 39±11 years, 6 males). The indication for EPS was: supraventricular tachycardia (SVT) ablation in 9 patients, syncope in 1 patient. High density three-dimensional electro-anatomic maps (EAM) were all obtained with a multipolar catheter during sinus rhythm (number of points: 8794±937 in basal maps and 9007±1296 after atropine, p=0,87). The response to atropine was documented by an increase in heart rate (mean increase 59 ± 19% of basal cycle length). All basal maps showed a similar pattern of fragmentation in the posterior-septal wall reflecting the anatomical distribution of right GPs. In particular, three main stations were identified in the supero-, mid- and infero-posterior regions. Fragmentation of EGMs was found to progress from the edge to the core of each area. After administration of atropine, a reduction in fractionated area was observed in all patients. Filtering the maps according to a cut-off of fragmentation ≥ 6 peaks allowed identification of the nucleus with the highest degree of variation after atropine injection (mean basal area = 0,89 ± 0,81 cm2 ; mean atropine area = 0,44 ± 0,56 cm2 p&lt;0,001).

Conclusion
Fragmentation of atrial electrograms is a dynamic property related to vagal output. High density mapping with a high pass filter of 6 peaks allows to identify the smallest vagal sensitive area in the anatomical stations of the GPs.
Trends in adoption of extravascular cardiac implantable electronic devices: the Dutch cohort
Authors: Breeman K T N , Knops R E , Van Der Stoel M D , Boersma L V A , Yap S C , Van Erven L , Van Dijk V F , Maass A H , Wilde A A M , Tjong F V Y 
Published: May 2024

Abstract

Introduction
Conventional implantable cardioverter-defibrillators (ICDs) and pacemakers carry a risk of mainly pocket- and lead-related complications. To avoid these complications, extravascular devices (EVDs) have been developed, such as the subcutaneous ICD (S-ICD) and leadless pacemaker (LP). However, data on the actual adoption of EVDs for patient or center characteristics is lacking.

Purpose
To assess real-world nationwide trends in adoption of EVDs in the Netherlands.

Methods
Using the Netherlands Heart Registration, all consecutive patients with a de novo S-ICD or conventional single-chamber ICD implantation between 2012-2020, or with a de novo LP or conventional single-chamber pacemaker implantation between 2014-2020 were included. Trends in adoption of EVDs are described for different patient and hospital characteristics (tertiles of device-implanting volume and whether cardiothoracic surgery back-up was available). Differences between patients with EVDs and non-EVDs and differences between implanting centers of EVDs and non-EVDs were tested for by Student’s T-test, Chi-square and Fisher’s exact test. Trends in adoption over time were calculated with linear and logistic regression analysis.

Results
From 2012-2020, 2190 S-ICDs and 10683 conventional ICDs were implanted; from 2014-2020, 712 LPs and 11103 conventional pacemakers were implanted. The general adoption of both increased (S-ICDs, 8% to 21%; LPs, 1% to 8%), but the increase seems to reach a plateau (Fig. 1). S-ICD recipients were younger than conventional ICD recipients (p&lt;0.001) and more likely to be female (p&lt;0.001); LP recipients were younger than conventional pacemaker recipients (p&lt;0.001) and more likely to be male (p=0.03). Both S-ICDs and LPs were mainly implanted in high-volume centers with thoracic surgery on-site (Fig. 2).

Conclusions
In this nationwide study we observed a relative quick adoption of innovative EVDs with a plateau after approximately 4 years. The relative adoption of S-ICDs is especially high in younger patients. EVDs are overall mainly implanted in high-volume centers with cardiothoracic surgery available. As LPs can only be implanted in centers with cardiothoracic surgery in the Netherlands, this may have limited its adoption.
Feasibility and safety of cavotricuspid isthmus ablation using exclusive intracardiac echocardiography guidance: a proof-of-concept, observational trial
Authors: Debreceni D , Kristof-Ferenc J , Toth D , Bocz B , Simor T , Kupo P 
Published: May 2024

Abstract

Introduction
Catheter ablation is the preferred treatment for typical atrial flutter (AFl), although it can pose challenges due to anatomical abnormalities. The integration of 3D electroanatomical mapping systems (EAMS) has notably diminished the need for fluoroscopy in AFl ablation procedures. Intracardiac echocardiography (ICE) has also demonstrated advantages in reducing radiation exposure during AFl ablation. Nevertheless, there is a lack of evidence on the feasibility of ICE-guided, zero-fluoroscopy AFl ablation without the use of EAMS.

Methods
In this prospective study, we enrolled 80 patients with CTI-dependent AFl. The initial 40 patients underwent ablation guided by standard fluoroscopy along with ICE (Standard ICE group), whereas the remaining 40 patients underwent zero-fluoroscopy ablation exclusively using ICE (Zero ICE group). Procedure outcomes, including acute success, procedural duration, fluoroscopy duration, radiation dose, and any associated complications, were compared between the groups.

Results
Both groups achieved a 100% acute success rate. In the Zero ICE group, the zero-fluoroscopy approach was successfully executed in 39 out of 40 cases (97.5%). There were no significant differences in procedure time (55.5 (46.5; 66.8) min vs. 51.5 (44.0; 65.5), p=0.50) and puncture to first ablation time (18 (13.5; 23) min vs. 19 (15; 23.5) min, p=0.50) between the groups. The Zero ICE group had significantly lower fluoroscopy time (57 (36.3; 90) sec vs. 0 (0; 0) sec, p&lt;0.001) and dose (3.17 (2.27; 5.63) mGy vs. 0 (0; 0) mGy, p&lt;0.001 compared to the Standard ICE group. Total ablation time was longer in the Standard ICE group (597 (447; 908) sec vs. 430 (260; 750), p=0.02), but total ablation energy (22458 (14836; 31116) Ws vs. 17043 (10533; 29302) Ws, p=0.10) did not differ significantly. First-pass bidirectional conduction block of the CTI and acute reconnection rates were comparable between the groups. No complications or recurrences were noted during the follow-up period.

Conclusion
ICE-guided, zero-fluoroscopy CTI ablation for AFl using only ICE is feasible and safe. This method effectively eliminates radiation exposure without compromising procedural duration, total ablation time, or acute success rates.isthmus ablation by ICE