bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robustness of electrocardiographic imaging in the presence of electrical noise
Authors: Molero R , Martinez-Perez M , Reventos-Presmanes J , Mont L , Climent A M , Guillem M S 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Other. Main funding source(s): Ministerio de Ciencia, Innovación y Universidades; Generalitat Valenciana

Background
Electrocardiographic Imaging (ECGI) allows evaluating the cardiac substrate non-invasively. However, the inverse solution is strongly dependent on the noise of the body surface signals. Zero-order Tikhonov regularization together with L-curve optimization, widely used in ECGI studies, allows minimizing the sources of noise to find an optimal solution.

Objective
Evaluate the effect of electrical and noise on the L-curve optimization in computer simulations of atrial activity and in the physiological interpretation of the inverse solution.

Methods
Five atrial simulations of regular rhythms (3 atrial flutter and 2 sinus rhythm) were used for computing the ECGI with five signal-to-noise ratios (SNR) (from 3dB to 40dB). ECGI was computed by zero-order Tikhonov regularization and L-curve optimization. The regularization parameter (λ) and the shape of the curve were analysed. Electrical noise was added to signals from an atrial flutter patient to study the effect on real ECGI signals. Local activation time (LAT) maps were obtained to evaluate the quality of the ECGI in front of noise. Correlation coefficient (CC) of LAT maps was computed between simulated electrograms and ECGIs.

Results
The level of noise was found to be correlated with the optimal regularization parameter (λ), (SNR 3dB, λ&gt;10-6, SNR 40dB, λ&lt;10-9). LAT maps for the optimal λ and higher were able to find relevant information about the simulation and patient independently on the SNR (CC3dB-EGM = 0.66±0.1, CC40dB-EGM = 0.76±0.1). Similar behaviour was observed in real atrial flutter signals (CC3dB-Ref = 0.83, CC10dB-Ref = 0.93). LAT maps from the atrial flutter were able to accurately locate the reentry circuit, as found in the electroanatomical map independently on the SNR.

Conclusion
LAT maps derived from ECGI are robust against the presence of noise. Although the reconstructed potentials are smoother with increasing levels of noise, LAT maps with and without noise show a good correlation thanks to an increased regularization.
Figure 1. A. Local activation times (LAT) map of a reference electrogram (EGM) from a computer simulation of sinus rhythm in the atria. B. Electrocardiographic imaging maps (ECGI) obtained from the simulation A for different levels of electrical noise and regularization parameters. C. Example of LAT map obtained with ECGI and the endocardial map of a typical atrial flutter together with LAT maps with increased electrical noise but comparable results (CC &gt; 0.83).
The predictive ability of the QT response in supine-standing test for drug induced QT prolongation
Authors: Hochstadt A , Viskin D , Moses A , Romer D , Viskin S , Chorin E 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
A significant cause of sudden cardiac death is arrhythmias induced by QT prolongation. The acquired long QT syndrome is much more common than the congenital form. A major cause of acquired long QT prolongation is drug exposure. Drug-induced QT prolongation is common when taking cardiac drugs such as antiarrhythmics but also common with other medication groups such as antibiotics, antihistamines, and psychiatric drugs. These medications prolong QT by inhibiting the HERG channel which controls the rectifier potassium current (IKr) and prolong depolarization. As HERG inhibition is multifactorial an individual’s effect of medications on QT is difficult to predict and thus leaving many patients with significant risk once they initiate treatment with such medications.
In the last decade, tests that measure the QT reaction to sudden changes in heart rate while changing position for supine to standing have shown usefulness in assessing the possibility of congenital long QT in patients with equivocal QT interval, probably by measuring the repolarization reserve which is deficient in patients with congenital long QT syndrome. Lol

Purpose
We sought to identify whether the same tests can be useful in prediction of acquired QT prolongation after exposure to HERG potassium channel suppressing medications.

Methods
Fifty four healthy volunteers undergone a supine-standing test where QT changes: QT stretching, and QT stunning were examined after brisk standing. Afterward the volunteers received one 400 mg dose of moxifloxacin, a drug known to prolong QT by affecting the HERG channel. Results of the standing test were compared to the drug effects on QTc and predictive ability was assessed.

Results
There was no significant correlation between the maximal drug evoked QTc prolongation and either change in QTc during the stretching or stunning phase (R=0.090, p= 0.538 and R=0.224, p=0.176 accordingly). Both stunning and stretching tests results did not differ significantly between patient with a significant (&gt;20msecs) QT prolongation in response to drugs and no such prolongation (p&gt; 0.361).
The area under the ROC curves of the QTc prolongation during both phases stunning phase did not show usefulness in predicting substantial QTc prolongation (&gt;20msec) during drug therapy with an AUCs of 0.593 (95% CI 0.418-0.769) and 0.617 (95%CI 0.375-0.859) accordingly.

Conclusions
Repolarization reserve assessment using a simple brisk standing test did not efficiently aid in predict QT drug response in patients treated with HERG inhibiting drugs.
Correlation of NT-proBNP and left atrial pressure in patients with atypical atrial flutter after cardiac surgery and previous catheter ablation
Authors: Bakytzhanuly A , Nuralinov O , Esilbayev Z H , Turubayev E , Bagibayev S , Smagulova A , Abdrakhmanov A 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Atypical atrial flutter (AFL) is often associated with cardiac surgery or extensive catheter ablation (CA) for the treatment of atrial fibrillation (AF). Therefore, the increase in the number of cardiac surgery procedures leads to the development of substrates for atypical AFL onset. Described several prognostic factors for the development of AF in the long-term period after cardiac interventions. To our knowledge, the prognostic factors of atypical AFL in patients after cardiac surgery are not described.

Objective
the aim of our study was to determine the relationship between increased left atrial pressure and the NT-proBNP biomarker in patients after cardiac surgery and catheter ablation.

Methods
Sixty-five adult patients with AFL after cardiac surgery and catheter ablation were included in a single-center prospective study. The patients' age varied from 18 to 76 years, and the mean age was 57.1±12.2 years. Of these, 36 patients were male (55.4%) and 29 women (49.3%), respectively. Patients were observed for NT-proBNP before index radiofrequency ablation (RFA). All patients underwent RFA of atypical AFL in the left atrium (LA) and measurement of LA pressure. The patients were discharged safely and were monitored for 12 months.

Results
According to basic characteristics of patients with atypical AFL cardiac surgery for valvular heart disease was performed in 30 (46.1%) cases, for ischemic and congenital heart diseases occurred with the same frequency, 8 (12.3%). Atypical AFL occurred in 20 (30.8%) cases after cryoballoon pulmonary veins isolation (PVI), after RFA of a typical AFL in 14 (21.3%) cases, and radiofrequency PVI in 13 (20%) cases. The mean invasive LA pressure before index RFA was 22.3±5 mm. Hg, mean LA size on transthoracic echocardiography was 42.3±6.9mm. The parameters of the left ventricle: mean EDV 93.3±26.1ml, mean ESV 41.7±16.9ml, and mean EF 56±7.6%. Mean NT-proBNP was 974.8±440.5 pg/ml. In our cohort of patients, we identified a positive correlation between NT-proBNP and LA pressure (p&lt;0.001, r=0.761), as well as a positive relationship between NT-proBNP and LA diameter (r=0.512, p&lt;0.001), between LA pressure and LA diameter (r=0.438, p&lt;0.001). Additionally, a correlation was found between the pulmonary artery systolic pressure and LA diameter (r=0.314, p=0.011).

Conclusions
Our study demonstrates a strong direct linear relationship of NT-proBNP with an increase of LA pressure in patients with atypical AFL in patients previously undergone cardiac surgery and catheter ablation. Thus, these parameters can serve as possible prognostic criteria for the development of complex cardiac arrhythmias such as atypical AFL.
Incidence of infranodal conduction delay in patients with left bundle branch block after transcatheter aortic valve replacement: impact of the 2021 ESC guidelines for cardiac pacing
Authors: Maeder N , Badertscher P , Serban T , Weidlich S , Nestelberger T , Leibundgut G , Kaiser C , Osswald S , Sticherling C , Knecht S , Kuehne M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Left bundle branch block (LBBB) remains the most frequent conduction disorder after transcatheter aortic valve replacement (TAVR). Electrophysiological (EP) testing is recommended in the 2021 ESC Guidelines for cardiac pacing with a IIa indication in patients with new LBBB with QRS ≥ 150ms or PR ≥ 240ms or with pre-existing LBBB with a delta of QRS/PR intervals of ≥ 20ms after TAVR. A cut-off for the HV interval of ≥ 70ms to consider pacemaker implantation was proposed. However, evidence for these proposed cutoffs is scarce in LBBB patients after TAVR.

Aims
To assess the incidence of infranodal conduction delay in patients with LBBB after TAVR and assess safety of predefined criteria for PR and QRS width to identify infranodal conduction delay.

Methods
We analyzed a consecutively included cohort of patients who underwent TAVR between August 2014 and May 2022. A 12-lead surface electrocardiogram (ECG) was available in all patients before and the day after TAVR. Patients with LBBB also received an EP testing the following day, irrespective of surface ECG measurements.

Results
Of 1033 patients who received TAVR between August 2014 and May 2022, 708 were included in the study (Figure). Mean age was 82 years, 53% were female. The used valve types were homogenously distributed. Among 708 patients, 180 patients demonstrated LBBB (25%) the next day (86%new-onset LBBB). Infranodal conduction delay, defined as a HV interval ≥ 70ms, was observed in 18/180 patients (10%) with LBBB on the day after TAVR. Using the new ESC guidelines, EP testing was indicated in 86 of 177 patients (49%) with LBBB after TAVR, with 14 of 18 (78%) being identified with an HV interval of ≥ 70ms (sensitivity 78%, negative predictive value 94%). Thus, in 4 patients (3 men) with new LBBB, the HV interval of ≥ 70ms would have been missed based on surface ECG readings suggested by current guidelines. Stratified by sex, the predefined criteria for PR and QRS demonstrated a sensitivity and negative predictive value of 86% and 98% in women and 72% and 90% in men, respectively.

Conclusion
In patients with LBBB after TAVR the incidence of infranodal conduction delay defined as a HV interval ≥ 70ms is 10%. Predefined surface ECG criteria offer excellent safety for rule out of infranodal conduction delay, especially in women, while caution might be advisable using the same criteria in men.
Mortality and ventricular arrhythmias in patients with atrial fibrillation on sotalol
Authors: Lenhoff H , Darpo B , Tornvall P , Petersson H , Frick M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Karolinska Institue at Stockholm South hospital.

Background
In atrial fibrillation (AF), anti-arrhythmic drugs are an option for rhythm control. Guidelines regarding treatment with sotalol varies worldwide. The risk of serious adverse events in AF patients on sotalol is estimated from small studies, with short follow-up, not designed for mortality analysis.

Purpose
To evaluate mortality in patients with a rhythm control strategy for AF.

Methods
In Swedish registries, 7473 sotalol-treated and 107255 patients on betablockers underwent cardioversion or were diagnosed with paroxysmal AF between 2006 and 2017. Mortality and ventricular arrhythmias were estimated in unadjusted, and propensity score matched cohorts.

Results
Mean follow up was 474 (SD 599) and 481 (SD 515) days in sotalol/betablocker respectively. Crude all-cause mortality was lower in the sotalol group (HR 0.3 CI 0.3-0.4), also in multi-adjusted analysis (HR 0.6 CI 0.5-0.6). In the propensity-matched comparison, HR remained lower on sotalol (0.6 CI 0.5-0.7). Ventricular arrhythmias were more common among patients on sotalol (1.5 vs 1,0%, p&lt;0,001. 1,1% vs 0,8%/100 personyears). There were no significant differences in CPR or sudden cardiac death.

Conclusions
This real-world data did not show increased mortality in sotalol-treated patients. Ventricular arrhythmias were relatively rare. Careful patient selection and follow-up probably reduce the proarrhythmic risk during sotalol-treatment.
Radiofrequency catheter denervation of sinus node by targetting the right anterior ganglionated plexus: towards minimizing the lesions set
Authors: Stiavnicky P , Wichterle D , Jansova H , Stojadinovic P , Peichl P , Haskova J , Cihak R , Kautzner J 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Radiofrequency catheter (RF) ablation of the superior ganglionated plexus (RAGP) that modifies parasympathetic innervation of the sinus node (SAN) is used for the treatment of functional bradyarrhythmias. The RAGP is usually targeted from the endocardial aspect of both the right and left atria.

Purpose
To investigate the acute effect of a minimized biatrial set of ablation lesions aimed at denervating the SAN.

Methods
In patients with cardioinhibitory reflex syncope (n=25) or symptomatic functional sinus bradycardia (n=7), a minimum of 2x2 and a maximum of 2x3 RF lesions (at the discretion of the operator) were created from both sides of the superior interatrial septum with a setting of 30 W / 30 s and strictly contralateral configuration. The response to extracardiac vagus nerve stimulation (ECVS) was assessed before and after ablation. This response was quantified by the ratio of the maximum induced P-P interval and the cycle length of the current sinus rhythm (MaxPPratio).

Results
In 32 patients (41±13 years, 56% men), ablation of RAGP (2x3 and 2x2 lesions in 23 and 9 patients, respectively) resulted in attenuation of the response to ECVS from 7.9±3.5 s to 0.9±0.2 s (Figure, left panel). After ablation, only 9 patients had MaxPPratio &gt;1.1 and none of the patients had MaxPPratio &gt;1.6 (Figure, right panel). In 6 patients with MaxPPratio &gt;1.3, the extension of original lesions easily suppressed the residual responsiveness of SAN to ECVS.

Conclusion
Biatrial RAGP ablation with a total RF time of 2-3 minutes resulted acutely in virtually complete SAN denervation in 72% of patients. Highly significant, but incomplete SAN denervation in remaining patients was successfully treated by extension of original ablation clusters. The long-term durability of SAN denervation associated with this ablation strategy remains to be investigated.
Immediate pericardial protamine administration in acute pericardial tamponade
Authors: Candemir B , Kuru B , Ersoy I , Atan S , Yamanturk Y Y , Izci I C , Beton O 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Aims
Cardiac tamponade (CT) is the most common life-threatening complication of interventional electrophysiology. Urgent drainage by percutaneous pericardiocentesis and anticoagulation reversal are required. Immediate direct protamine administration to the pericardial space to the patient has not been described. This study was designed to assess the efficacy and safety of immediate intrapericardial protamine administration (IPPA) in CT as a complication of interventional electrophysiologic procedure.

Methods
A retrospective case series of IPPA performed for CT was collected. Urgent drainage by percutaneous pericardiocentesis and IPPA were performed to achieve hemodynamic stabilization without emergent surgery.

Results
Eleven cases of IPPA were included in two tertiary heart centres. Electrophysiological procedures were performed for ventricular tachycardia (n =3), atrial fibrillation (n = 3), left accessory pathway (n = 1), and premature ventricular contraction (n =4) with transseptal (n = 10) and/or retroaortic routes (n =3). Pericardial drainage was performed by percutaneous pericardiocentesis for all 11 patients. Surgical haemostasis was not required for our cohort. The mean volume of drained pericardial fluid was 486ml (200-1200) Mean IPPA dosage was 209mg (100-800). Mean systemic protamine dosage was 86mg(50-100). No complication was observed on the follow-up.

Conclusion
IPPA is a feasible, safe, and useful technique for salvage therapy in CT.

Conclusion
IPPA is a feasible, safe, and useful technique for salvage therapy in ACT in interventional electrophysiology.
Impact of ultra-short pauses between stacked lesions with and without active esophageal cooling
Authors: Mercado Montoya M , Gomez Bustamante T , Kulstad E , Berjano E , Mickelsen S , Hernandez Arango P , Gonzalez Suarez A , Schieber J , Daniels J 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Research reported in this abstract was supported by the National Heart, Lung, And Blood Institute of the National Institutes of Health under Award Number R44HL158375 (the content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health).

Background
Placing lesions at the same point (stacking lesions) in the left atrium during radiofrequency (RF) ablation can increase the risk of collateral injury. The use of active esophageal cooling has been shown to significantly reduce the risk of thermal injury to the esophagus, but stacking of lesions may overcome these protective effects. Longer pauses between lesions may reduce this risk, but the effect of very short pauses has not been previously quantified.

Purpose
To examine the impact of ultra-short pauses between stacked lesions with and without active esophageal cooling.

Methods
Using a computational model of the left atrium, we measured the effect of RF ablation in the left atrium on injury formation in the esophagus. Models with and without active esophageal cooling, using a dedicated esophageal cooling device, were created. Using a power of 50 W for 10 s, with up to 3 sequential lesions placed in the same location, we used the Arrhenius equation to quantify the fraction of damage (FOD) in the esophageal wall. The time between lesions was set to as short as 1 s, and results were compared to prior studies using longer pauses of up to 20 s. To account for thermal latency, measures of esophageal damage were taken both immediately after RF ablation, and again 90 s afterwards.

Results
With active cooling in place, esophageal injury was eliminated with active esophageal cooling after the first lesion placement, but reached 21% transmurality without cooling. Lesion transmurality increased after each lesion due to thermal latency, but active esophageal cooling prevented this effect when only one lesion was placed. Subsequent lesions resulted in esophageal injury when placed in the same location. After 3 lesions with 1 s pauses between each, esophageal injury transmurality reached 91% without cooling in place, and 22% with active cooling in place (Figure 1). In contrast, analysis of the intended lesions in the atrial wall demonstrated minimal effects from cooling (Figure 2).

Conclusions
Active esophageal cooling significantly reduces esophageal injury from RF ablation, but placing additional lesions at the same point can overcome the heat extraction capacity of a dedicated cooling device. Decreased time between lesions exacerbates this risk, with an ultra-short pause of one second posing the greatest risk.
Reduction in procedure duration when utilizing active esophageal cooling in patients with persistent atrial fibrillation - update from a large hospital registry
Authors: Cooper J , Joseph C , Willms D , Ruppert A , Francisco G , Kulstad E , Athill C 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, And Blood Institute of the National Institutes of Health.

Background
During left atrial ablation, lesions may be placed on the posterior wall of the left atrium. Due to the anatomical proximity of the left atrium to the esophagus, there is significant risk for thermal esophageal injury and potentially atrio-esophageal fistula. Ablation of persistent atrial fibrillation (AF) may involve even more lesion placement, and increased risk and procedure time as a result. In order to protect the esophagus, there are two main methods of esophageal protection, luminal esophageal temperature (LET) monitoring and active esophageal cooling. Recent studies have compared LET monitoring to active cooling and found a reduction in overall esophageal injury when utilizing active cooling, in addition to a reduction in procedure time. However, these studies generally included all patients with AF regardless of which type.

Purpose
We aimed to investigate the association between procedure duration and esophageal protection method among persistent AF patients.

Methods
In this study, we obtained data from an existing clinician-maintained hospital registry. We collected procedure durations from patients with persistent AF undergoing left atrial ablation from January 2018 to May 2022. All patients that met these criteria were included.

Results
Data were analyzed from 161 patients. Active esophageal cooling was utilized in 90 procedures, while LET monitoring was utilized in 71 procedures. The median procedure duration in the actively cooled group was 146 minutes with an interquartile range (IQR) of 58. The median procedure duration in the LET monitored group was 173 minutes with an IQR of 60. This represents a median difference of 27 minutes or 16% of the total procedure duration (p&lt;.001)

Conclusions
The use of active esophageal cooling is associated with a significant reduction in overall procedure time among patients with persistent atrial fibrillation.