bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical recurrence of palpitations following slow pathway ablation in patients with suspected paroxysmal supraventricular tachycardias but non-documented, non-inducible tachycardias
Authors: Ramos Jimenez J , Marco Del Castillo A , Lozano Granero VC , Lazaro Rivera C , Salgado R , Rodriguez Manero M , Ramos Fernandez P , Dallaglio P , Gunturiz Beltran C , Alonso Fernandez P , Ayala HD , Jimenez Sanchez D , Lopez Gil M , Arribas Ynsaurriaga F , Rodriguez Munoz DA 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Catheter ablation is recommended as first-line treatment in patients with atrioventricular nodal reentry tachycardias (AVNRT). However, the best therapeutic modality in patients with dual AV nodal physiology but non-inducible tachycardias in electrophysiological study (EPS) remains controversial, especially when no tachycardias have been documented.
Our objective was to evaluate the results of empirical slow pathway ablation in patients showing dual AV nodal physiology but non-inducible AVNRT.

Methods
Multicenter, retrospective, observational registry of consecutive patients undergoing EPS due to clinical suspicion of paroxysmal supraventricular tachycardias (PSVT), but with no prior ECG documentation. Clinical, EPS and ablation (when performed) data were collected and andalyzed.

Results
427 patients of 12 centers were included. Mean age was 46.3 ±16.1 and 297 (69.6%) were females. AVNRT was induced in 188 patients (typical in 181 cases, atypical in 7). Dual AV nodal physiology with or without single nodal echo beats, but with no sustained tachycardia and without evidence of accessory pathway was present in 68 patients. Ablation of the slow pathway was performed in 187/188 patients with AVNRT and in 30/68 patients with dual physiology. Among subjects with non-inducible tachycardia, ablation reduced significantly recurrences (39.5% in non-ablated vs. 16.7%; p = 0.04), with a level equivalent to those with ablated AVNRT(14.4% vs. 16.7%; p = 0.75). Procedure-related complications were similar in both groups: empirical ablation n = 1; 3.3% vs. induced tachycardia n = 6; 3.2% (p = 0.98).

Conclusions
In patients with high clinical suspicion of PSVT but non-documented and non-inducible arrhythmias, the presence of dual AV nodal physiology makes AVNRT a likely mechanism of the clinical tachycardia. Catheter ablation of slow pathway reduces the risk of recurrence to a level equivalent to those with inducible and ablated AVNRT. AVNRT (n = 188) Dual nodal physiology (n = 68) p value Age (years) 48.6 ± 16.3 41.9 ± 14.0 &lt;0.01 Female 71.8% 67.7% 0.52 Years symptomatic 9.3 ± 11.3 3.6 ± 8.1 &lt;0.01 Sudden onset 83.9% 88.0% 0.54 Abrupt end 73.4% 74.6% 0.96 Previous rate-slowing drugs 30.9% 25.0% 0.36 Previous antiarrhythmic drugs 5.9% 2.9% 0.35 Isoproterenol in EPS 70.0% 89.7% &lt;0.01
Radiofrequency catheter ablation of focal atrial tachycardia: characteristics and results of a series in a tertiary hospital
Authors: Castelo A , Portugal G , Vaz Ferreira V , Garcia Bras P , Teixeira B , Valente B , Cunha P , Guerra C , Delgado A , Cruz Ferreira R , Oliveira M 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Focal atrial tachycardia (AT) is a relatively uncommon arrhythmia with poor response to medical treatment. Radiofrequency (RF) ablation appears to be a good option for treatment of symptomatic patients (P).

Purpose
To describe the clinical characteristics, electrophysiological (EP) findings, safety and short-term efficacy of catheter ablation in P with AT.

Methods
Retrospective analysis of consecutive P submitted to AT ablation using electroanatomical mapping between 2015 and 2020. If the AT was not present spontaneously, pacing maneuvers (atrial drive or burst pacing with up to 3 extra-stimuli) and isoprenaline was employed until reproducible induction of an ectopic atrial rhythm. Radiofrequency (RF) ablation was delivered at the site of earliest activation after validation of local electrograms until non-inducibility.

Results
A total of 46P (61% female) were included, with a mean age of 48 ± 23 years (minimum 8 months, maximum 86 years). Idiopathic AT was observed in 47,8%, while 52.2% had other relevant comorbidities (chronic pulmonary disease 17.4%; previous cardiac surgery 8,7%; congenital heart disease 10.9%; coronary artery disease 6.5%). Despite anti-arrhythmic therapy, daily palpitations were present in 87% of the cases and dizziness or syncope occurred in 22%). Nearly half (47.8%) had previously sought urgent medical care and 30.4% had a hospital admission due to arrhythmia. The clinical arrhythmia was documented in 34P (47.8% by 12-lead electrocardiography and 26.1% in 24h Holter monitoring). During the EP study a focal AT was documented in all P (spontaneously in 54.3% and induced with pacing maneuvers in 45.7%). AT origin after electroanatomical activation mapping is depicted in figure 1. After focal RF ablation, a second AT was induced in 16P (34.8%) and a new ablation was performed in 15 cases (93.8%). Total RF time was 508 ± 386 sec. One P developed right phrenic nerve palsy after ablation on the lateral wall of the right atrium. No other complications were noted. On follow-up (mean 320 ± 92 days), symptoms improved in 88.1% of the P, with a 3-fold decrease in urgent medical care visits and hospital admission for arrhythmia. Three P (8.7%) were submitted to a new EP study, in which an AT was documented and ablated in 2P.

Conclusion
AT is a very symptomatic arrhythmia, associated with increased usage of hospital resources and poor response to antiarrhythmic therapy. Ablation is an efficient treatment option, with a high success rate, low rate of complications and short-term clinical benefits. Abstract Figure. Distribution of focal atrial tachycardia
Low-fluoro workflows and impact in radiation exposure in the electrophysiology lab
Authors: Ferreira V , Portugal G , Cruz Coutinho M , Silva Cunha P , Valente B , Lousinha A , Castelo A , Garcia Bras P , Grazina A , Guerra C , Delgado A , Paulo M , Cruz Ferreira R , Oliveira M 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
During electrophysiology (EP) procedures, fluoroscopy imaging is employed to visualise catheters position in real-time. However, ionizing radiation is a health hazard to both the patient and operator. In recent years, the use of electroanatomical mapping systems and operator adoption of low-fluoro workflows has allowed a reduction of radiation exposure. The aim of this study was to assess the evolution of fluoroscopy time (FT) in EP procedures, using conventional technique or an electroanatomical mapping system (EMS).

Methods
A retrospective analysis of consecutive EP procedures performed at a tertiary centre between September 2018 and October 2020 was conducted. The procedures were divided in 3 tertiles according to date (T1, T2 and T3), with T3 corresponding to the most recent interventions. Procedural duration, FT, use of EMS, radiofrequency time (RT), acute ablation success and procedural complications were examined.

Results
A total of 615 procedures were analysed: atrioventricular node reentry tachycardia (AVNRT) – n = 144, accessory pathways (AP) – n = 83, typical atrial flutter – n = 106, atrial fibrillation (AF) ablation with radiofrequency (RF) – n = 61, AF ablation with cryoballoon – n = 92, ablation of ventricular arrhythmias – n = 53, and 75 miscellaneous procedures (including atrioventricular node ablation, left atrial flutter ablation and cardioneuroablation). Mean age was 54.6 ± 18.2 years with 59.4% male sex patients. An EMS was used in 75% of the procedures, without significant differences between tertiles. A progressive reduction in median FT was observed over the tertiles (T1 6.3 min, interquartile range [IQR] 2.9-13.6; T2 5.4 min, IQR 2.1-12.0, and T3 3.1 min, IQR 1.2-7.2, Figure 1), and a statistical significant difference was found when comparing T1 to T3 (p &lt; 0.001) and T2 to T3 (p &lt; 0.001). The decrease in FT was observed throughout the study period for all different EP procedures (Figure 2). The number of procedures with zero fluoroscopy had gradually increased (T1 6.1%, T2 8.5% and T3 14.1%; T1 vs. T3 p &lt;0.01). Younger patients (&lt;20 years) were submitted to low fluoroscopy doses with a significant decrease over tertiles (T1 1.2 min, IQR 0.0-4.3; T2 0.9 min, IQR 0.0-2.5; T3 0.0, IQR 0.0-2.2, T1 vs.T3 p &lt; 0.001). No significant difference in procedural duration, RT, acute procedural success or complication rate were noted between tertiles.

Conclusion
Reduction in radiation exposure can be achieved without compromising duration, safety and effectiveness of the procedure. The commitment of operators to reduce radiation exposure using 3D mapping technology can lead to a significant decrease in the use of fluoroscopy. Abstract Figure. Fluoroscopic time analysis
Safety of catheter ablation of AF without pre- or periprocedural imaging for the detection of LA thrombus
Authors: Vlachos K , Bazoukis G , Prappa E , Megarisiotou A , Dragasis S , Mililis P , Saplaouras A , Efremidis T , Sideris A , Efremidis M , Letsas K 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The need for pre- or peri-procedural imaging to rule out the presence of left atrial thrombus in patients undergoing catheter ablation of atrial fibrillation (AF) is unclear in the era of uninterrupted direct oral anticoagulant (DOAC) regimen. We sought to examine the safety of catheter ablation in appropriately selected patients with paroxysmal AF without performing screening for left atrial thrombus.

Methods
Consecutive patients planned for radiofrequency AF catheter ablation between January 2016 and June 2020 were enrolled, and prospectively studied. All subjects were receiving uninterrupted anticoagulation with DOACs for at least 4 weeks before the procedure. All subjects were in sinus rhythm the day of the procedure. The primary outcome of the study was ischemic stroke or transient ischemic attack (TIA) during at 30 days.

Results
A total of 451 patients (age 59.7 ± 10.2 years, 289 males) with paroxysmal AF were included in the study. The mean CHA2DS2-VASc score was 1.4 ± 1.2. The mean left ventricular ejection fraction and left atrial diameter were 60 ± 5% and 39.3 ± 4 mm, respectively. Regarding the anticoagulation regimen, apixaban was used in 197 (43.6%) patients, rivaroxaban in 148 (32.8%) patients, and dabigatran in 106 (23.5%) patients. None of the patients developed clinical ischemic stroke or TIA during the 30-day post-discharged period.

Conclusions
Catheter ablation can be safely performed in low-risk patients with paroxysmal AF without imaging for the detection of left atrial thrombus in the era of uninterrupted DOAC anticoagulation.
Prevalence and predictor factors of persistent pulmonary vein isolation in redo AF ablation procedure
Authors: Ribeiro Da Silva M , Santos Silva G , Ribeiro Queiros P , Teixeira R , Almeida J , Fonseca P , Oliveira M , Goncalves H , Rodrigues A , Primo J , Fontes Carvalho R 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Atrial fibrillation (AF) catheter ablation is a well-established procedure for the treatment of AF. The cornerstone of AF ablation is the complete isolation of pulmonary veins (PV). However, persistent PV isolation (PVI) is difficult to accomplish, with PV reconnection rates of &gt; 70%. The factors associated with persistent PVI are still uncertain.

Purpose
To assess the PVI status in patients (pts) undergoing a redo ablation and to determinate the predictors associated with persistent PVI.

Methods
Consecutive pts who underwent a redo ablation between 2016 and 2020 were identified in a single-centre retrospective study. PVI status was assessed during electrophysiologic study with electroanatomic mapping system. Index procedures included second generation cryoballoon (CB), conventional radiofrequency (RF) before 2018 and CLOSE protocol guided RF ablation after 2018. Persistent PVI was defined by the absence of reconnection of all pulmonary veins.

Results
We included 83 pts with a mean age of 55,9 ± 11,9 years; 71,1% (n = 59) were male with a mean CHA2DS2-VASc score of 1,14 ±1,0. Seventy-five percent had paroxysmal AF and undergone a redo 35,0 months (±30,9) after the index PVI.
Seventeen pts (20,5%) had persistent PVI whereas 66 pts (79,5%) had at least one PV reconnected after the index procedure, with a reconnection rate of 51,8% for right superior and inferior PV, 47,0% for left superior PV and 36,1% for left inferior PV.
No statistically significant differences were noticed between pts with persistent and non-persistent PVI in baseline (clinical and echocardiographic) characteristics.
Regarding index ablation procedure, persistent PVI occurred more frequently in patients who underwent a "CLOSE" protocol-guided index PVI compared to RF pre-2018 and CB (45,5% vs 16,7%; p = 0,043).
Twenty-nine percent of pts with persistent PVI had a "CLOSE" protocol-guided index PVI whereas only 9,1% of non-persistent PVI pts had a "CLOSE" protocol-guided index PVI (p = 0,043).
In this cohort, "CLOSE" protocol-guided index PVI was the only predictor of persistent PVI (odds ratio 4.2, 95% confidence interval 1.1-15.9; p = 0.037).

Conclusions
In patients undergoing redo AF ablation procedures, only 20,5% had persistent PVI. "CLOSE" protocol-guided index PVI presented significantly higher rates of persistent PVI. "CLOSE" protocol-guided index PVI was the only predictor for persistent PVI in patients with AF recurrence requiring a redo procedure.
Risk factors for the development of arrhythmias after the fontan surgery
Authors: Fernandez Domenech J , Ortiz-Solis WA , Cueva-Parra A , Gomez-Flores JR , Nava-Townsend S 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Fontan surgery or total cavopulmonary connection is a palliative procedure for complex congenital heart disease with univentricular physiology, without the possibility of biventricular surgical correction. This surgery has a high mortality rate (70%), with heart failure and arrhythmias being the main causes of death.

Objective
Identify the pre, intra and post-surgical factors that may predispose to arrhythmias in patients undergoing to Fontan surgery.

Methods
We conducted a retrospective review of the patients who underwent a total cavopulmonary connection from January 2003 to December 2018. We performed an analysis employing the Chi-square test to determine which variables were associated with the development of arrhythmias.

Results
During the mentioned period, 115 patients underwent to Fontan surgery, of which 51.3% were women, the average age at the time of surgery was 8 years. The most frequent diagnosis was tricuspid atresia in 44 patients (38.2%), followed by pulmonary atresia in 18 patients (15.7%) and double outlet right ventricle in 14 patients (12.2%).
Regarding the type of the procedures performed, 93.9% (n = 108) were total extracardiac cavopulmonary connection and 6.1% (n = 7) were intracardiac. Also, 8.6% (n = 10) were taken to fenestration, the mean size of the fenestration was 7 mm (7 ± 3 mm)
After Fontan surgery, there was a high incidence of arrhythmias which was 38% (n = 44). 22 patients (50%) presented them in the late postoperative period, being this, the most frequent time for the appearance of arrhythmias.
We found that the intracardiac surgery presented an OR of 4.423 (95% CI 0.819 - 23.879, p&gt; 0.05), being not statistically significant. Instead, the bidirectional cavopulmonary shunt previous to the Fontan surgery presented an OR of 0.255 (95% CI 0.081 - 0.806, p &lt;0.05) and on the other hand the QRS duration &gt; 120 ms was significantly associated with the appearance of arrythmias with an OR 2.99 (95% CI 1.2-4.2, p &lt;0.05).

Conclusions
In patients undergoing to Fontan surgery, the previous bidirectional cavopulmonary bypass is a protective factor for the development of arrhythmias. And an QRS duration &gt; 120 ms is a parameter that predicts the apparence of arrhythmias. Abstract Figure. QRS INTERVAL POST FONTAN SURGERY
Impact of guideline-based medical therapy on malignant arrhythmias and mortality among heart failure patients implanted with a primary prevention ICD/CRTD
Authors: Rav Acha M , Farkash R , Davarashvili I , Glikson M , Hasin T 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
In contrast with the well-established impact of heart failure (HF) medical treatment reducing HF hospitalizations and improving survival, its impact on ventricular arrhythmia (VA) is based mainly on circumstantial evidence.

Aim
To evaluate prevalence of HF medical treatment and its impact on VA and overall survival among HF patients implanted with primary prevention ICD/CRTD.

Methods
Single center retrospective analysis of all HF patients implanted with ICD/CRTD as primary prevention. Patients" indication for implant according to guidelines was confirmed by a senior EP physician. Thereafter, the association of HF medications and dose (% guideline recommended target dose) of beta-blockers (BB), Angiotensin-antagonists (AgA), Mineralocorticoid-antagonsits (MRA), and Anti-Arrhythmic Drugs (AAD) with VA episodes and overall mortality was analyzed, based on patients" medical records and device clinic regular interrogations.

Results
186 HF patients qualifying for primary prevention ICD/CRTD implant according to HF and device guidelines, were included. Their mean ± SD age 66.4 ± 12 years, 15.1% female, 79 (42.5%) implanted with an ICD and 107 (57.5%) with CRTD. During 3.8 [2.1;6.7] (median[IQR]) years; 52 (28%) had VA and 77 (41.4%) died. Treatment (medication, % of patients) included: BB (83%), AgA (87%), MRA (59%), and AAD (43.5%). Doses were 25[12.5;50]% of target for BB or AgA and 25[0;50]% of target for MRA. Treatment with &gt;25% target dose of BB was associated with significantly reduced VA incidence. In a multivariable model including age, gender, diabetes, heart rate, and medication doses, increased BB dose was significantly and independently associated with reduced VA (HR 0.443 95%CI 0.222-0.885; p = 0.021). Kapkan-Myer analysis for survival without VA according to each medication group dose, supported reduced VA among patients receiving &gt; median dose of BB (Figure 1). Multivariable model for overall mortality including age, gender, renal disease, VA, and medical treatment; VA was associated with increased mortality (HR 2.672; 95% CI 1.429-4.999; p = 0.002) while AgA treatment was significantly and independently associated with reduced mortality (HR 0.515; 95% CI 0.285-0.929; p = 0.028).

Conclusions
In this cohort of real-life HF patients discharged after primary prevention ICD/CRTD implant, most of the patients were prescribed with guideline-based HF medications albeit with low doses. Higher BB dose was associated with reduced VA, while treatment with AgA was associated with improved survival. Abstract Figure. Survival without VA according to HF medi
Increasing adiposity and metabolic dysfunction prolong QTc interval and increase risk of ventricular arrhythmias: results from the UK Biobank
Authors: Patel K , Li X , Xu X , Sun L , Ardissino M , Punjabi P , Purkayastha S , Peters N , Ware J , Ng FS 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): National Institute for Health Research
Background/purpose: Small-scale studies have associated obesity and metabolic ill-health with QTc interval prolongation. Whether these associations are modulated by an underlying genetic predilection and translate into higher risks of ventricular arrhythmias (VA) is unknown.

Methods
Using the UK Biobank and adjusted multivariate regression analysis, we studied the associations between QTc and clinical measures of adiposity and metabolic ill-health. A polygenic risk score was used to determine whether these associations are modulated by a genetic predilection for QTc prolongation. We compared QTc between four clinical phenotypes defined according to presence (+) or absence (-) of obesity (Ob), and metabolic ill-health (MU). Logistic regression was used to calculate odds ratios (OR) for VA amongst these groups.

Results
23,683 individuals (11,563 male, mean age 61.0 + 7.5years) had ECG and clinical data available. QTc prolongs with increasing body mass index (0.76ms/kg/m2, 95%CI: 0.68-0.83ms/kg/m2), body fat (0.45ms/%, 95%CI:0.39-0.50ms/%), hip girth (0.35ms/cm, 95%CI:0.31-0.39ms/cm) and waist girth (0.32ms/cm, 95%CI:0.29-0.35ms/cm); all p &lt; 0.001. Genetically determined repolarisation reserve has no significant modulatory effect on the QTc-prolonging effects of increasing adiposity. Referenced to Ob-MU-, Ob + MU- and Ob-MU+ independently prolong QTc to a comparable extent, and Ob + MU+ has an additive effect on QTc prolongation. With reference to Ob-MU-, OR for VA in Ob-MU+ males and females were 5.96 (95%CI:4.70-7.55) and 5.10 (95%CI:3.34-7.80), respectively. OR for Ob + MU+ were 6.99 (95%CI:5.72-8.54) and 3.56 (95%CI:2.66-4.77) in males and females, respectively, (all p &lt; 0.001, see Table).

Conclusion
Adiposity and metabolic perturbation prolong QTc to a similar extent, and their co-existence exerts an additive effect. These effects are independent of genetically determined repolarisation reserve. Despite their comparable QTc prolonging effects, metabolic ill-health is associated with higher OR for VA than obesity. VA in obesity and metabolic dysfunctionReference phenotypeOb + MU-Ob-MU+Ob + MU+Ob-MU+male1.10(0.87-1.39)ns5.96 (4.70-7.55)***6.99(5.72-8.54)***female0.87(0.64-1.18)ns5.10(3.34-7.80)***3.56(2.66-4.77)***Ob + MU-male--6.01(4.98-7.26)***female--5.61(4.18-7.52)***Ob + MU+male--1.25(1.05-1.49)*female--1.16(0.80-1.68)nsOb, obese; MU, metabolically unhealthy; +, presence; -, absence; ns, non-significant; *p &lt; 0.05; ***p &lt; 0.001. Abstract Figure. QTc in obesity and metabolic dysfunction
Global cardiac sympathetic denervation is associated with diffuse myocardial fibrosis in non-ischemic cardiomyopathy
Authors: Chen HS , Jungen C , Kimura Y , Dibbets-Schneider P , Piers SRD , Androulakis AFA , Van Der Geest RJ , Lamb HJ , Scholte AJHA , De Geus-Oei LF , Jongbloed MRM , Zeppenfeld K 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background

Occurrence of ventricular tachycardias (VT) has been related to changes in sympathetic innervation and myocardial tissue in ischemic cardiomyopathy. In non-ischemic cardiomyopathy (NICM) patients with VT, the relation between global cardiac sympathetic innervation and non-ischemic fibrosis is less clear. The current gold standard in electrophysiology to identify non-ischemic fibrosis relies on unipolar endocardial voltage mapping.

Objective
To establish the relationship between global cardiac sympathetic innervation and global fibrosis.

Methods
29 patients (93% male, 58 ± 14 years, mean LVEF 38%±13) from the ‘Leiden Nonischemic Cardiomyopathy Study’ undergoing VT ablation between 2011-2018 were included. Endocardial voltage mapping was performed and the mean endocardial unipolar voltage (UV) was taken as a surrogate for global fibrosis. Global cardiac sympathetic innervation was analyzed by 123-I-MIBG imaging using heart-to-mediastinum ratio (HMR). A cut-off of 1.8 was used to delineate between normal (&gt;1.8) and denervated (&lt;1.8). HMR was correlated with mean UV.

Results
For patients with global cardiac sympathetic denervation a linear relationship was present between HMR and mean UV (R = 0.5278, P = 0.0431. There was no significant linear relationship for patients with normal cardiac sympathetic innervation between HMR and mean UV (R=-0.1696, P = 0.5795).

Conclusion
Global cardiac sympathetic denervation is related to myocardial fibrosis in patients with NICM and VT. The data support an interplay between denervation and fibrosis which may contribute to arrhythmogeneity, as observed in ICM. Abstract Figure.