bluuebunny/crossref_metadata_2025 huggingface dataset:
224Wireless ECG embedded in a necklace enables reliable detection of atrial fibrillation
Authors: Santala O E , Lipponen J A , Jantti H , Rissanen T T , Halonen J , Hartikainen J , Kolk I , Pohjantahti-Maaroos H , Tarvainen M P , Valiaho E-S , Martikainen T
Published: June 2020

Funding Acknowledgements

Goverment grant, Heart2save Ltd cooperation.

Background/Introduction:

Atrial fibrillation (AF) is the most common arrhythmia and a fast-growing public health problem worldwide. Main and the most severe complication of AF is an embolic stroke. Approximately 25% of all strokes are caused by AF. AF is often symptomless and intermittent, making its detection and diagnosing challenging. Many AF patients have both symptomatic and asymptomatic periods of arrhythmia. In addition, during the early stage of the disease, AF is often paroxysmal making the diagnosis of AF a major clinical challenge.

Purpose

Wearable ECG devices could enable repetitive rhythm monitoring over a long term and thus improve the probability of AF detection. Wearable devices have the advantage of being easily available. However, they also need to be reliable and their design should appeal customers. Our aim was to study the suitability and reliability of novel measurement technique (necklace-ECG, Figure1) for the diagnosis of AF.

Methods

The study population consisted of 145 adult volunteers at Kuopio University Hospital emergency department (66 AF and 79 sinus rhythm (SR), diagnosed from continuous 3-lead ECG recording. All study subjects performed a thirty-second self-performed ECG recording with a single-lead necklace-embedded ECG recorder (necklace-ECG) keeping the recorder between palms of their hands. The ECG recordings were analyzed with automatic AF detection algorithm. Two cardiologists interpreted independently in blinded fashion the necklace-ECG recordings and simultaneously registered 3-lead ECGs which served as golden standard for the final rhythm diagnosis.

Results

Necklace-ECG produced an interpretable ECG recording in 91.0%/86.2% patients (Doc1/Doc2, respectively). Additionally, 93.1% of ECG recordings were interpretable by the automatic analysis service (98.7% in SR patients and 86.4% of AF patients).

Base on the necklace ECG recording, cardiologists were able to diagnose AF with sensitivity of 98.2%/96.3% (Doc1/Doc2, respectively) and specificity of 100% (Doc1 and Doc2, respectively). The automatic arrhythmia algorithm diagnosed AF with sensitivity of 94.7% and specificity of 100%.

Conclusions

The necklace-ECG device produces ECG recording with sufficient quality for the detection of AF with good sensitivity and specificity as evaluated both by cardiologist and automated AF-detection algorithm. Thus, wearable necklace-ECG provides a new and easy method for screening, identifying and diagnosing AF.

Abstract Figure 1
P497Arrhythmic burden in patients with filamin C (FLNC) truncating variant associated cardiomyopathy
Authors: Zupan Meznar A , Zizek D , Breskvar Kac U D , Writzl K , Jan M , Toplisek J , Baraga M , Sinkovec M
Published: June 2020

Background

Truncating variants in FLNC gene are associated with an overlapping phenotype of arrhythmogenic and dilated cardiomyopathy. There are reports of high arrhythmia propensity with sudden cardiac death (SCD) often being the first symptom of the disease. It has been suggested that the current European guidelines primary prevention (PP) recommendation about implantable cardioverter-defibrillator (ICD) implantation might not be applicable in these patients and that earlier intervention should be considered.

Purpose

We sought to investigate the arrhythmic burden in FLNC truncation carriers in our centre.

Methods

Adult FLNC truncation carriers diagnosed in our centre between the years 2018 and 2019 were included in the study. We retrospectively analysed clinical data, and ICD follow-up reports in the cohort. Patients implanted with an ICD were divided in 3 groups: group A (secondary prevention ICD implantation), group B (PP indication according to the current guidelines – left ventricular ejection fraction (LVEF) below 35%) and group C (early PP– FLNC truncation carrier, LVEF < 50% and late gadolinium enhancement on cardiac magnetic resonance). We report the number of patients experiencing SCD and the number of appropriate and inappropriate ICD therapies per group.

Results

Twenty-four adult patients from 3 different families with three distinct FLNC truncating variants were identified. Ten (42%) were male; the average age was 45 ± 14 years. There were 3 (13%) SCDs in one family (2 male and one female, 29-42 years old) and two (8%) aborted SCDs in the remaining two families (one male and one female, 66 and 51 years old). Altogether eleven (46%) patients were implanted with an ICD. There were three patients in group A (2 aborted SCDs and 1 sustained ventricular tachycardia (VT)), two patients in group B and six patients in group C. Average ICD follow-up times were 42, 48 and 6 months for groups A, B and C, respectively. Eight appropriate ICD therapies occurred in 3 patients (27%). In group A, there were four sustained VT episodes successfully converted with an anti-tachycardia pacing (ATP) in two patients (67%); the average time to first therapy was 33 months. In group B, there was one appropriate shock for ventricular fibrillation (VF), and three sustained VT episodes in one patient (50%), time to first therapy was 60 months. After six months follow-up, there were no appropriate therapies registered in group C. Two patients (18%) experienced inappropriate shocks due to sinus tachycardia, one in group A and one in group C.

Conclusion

One-fifth of FLNC truncation carriers in our cohort experienced SCD. When patients received an ICD according to the current guidelines, majority experienced appropriate ICD therapy. Further clinical studies with longer follow-up will be needed to define appropriate risk stratification and optimal timing for prophylactic ICD intervention in these patients.
P531Cardiac resynchronization therapy in patients with permanent atrial fibrillation: insights from the HMEA database
Authors: Rapacciuolo A , Solimene F , Iacopino S , D"onofrio A , Pisano" E , Zanotto G , Curnis A , Capucci A , Senatore G , Pignalberi C , Maglia G , Santamaria M , Giacopelli D , Gargaro A , Della Bella P
Published: June 2020

Funding Acknowledgements

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Background/Introduction: The benefits of cardiac resynchronization therapy with defibrillator (CRT-D) in heart failure are well established. However, a gap of evidence is still present for patients with permanent atrial fibrillation (perm-AF)

Purpose

To investigate outcomes of CRT-D patients with perm-AF in terms of appropriate shock for ventricular arrhythmia and all-cause mortality in a long-term time horizon. 

Methods

We used the Home Monitoring Expert Alliance (HMEA) database, a nationwide data repository of daily remote monitoring transmissions. The episodes with delivered shock were adjudicated by a board of 3 electrophysiologists.

Results

Among 1226 CRT-D patients (mean age 71.2 ± 10.0 years; 75.5% males), 276 (22.5%) had perm-AF at device implantation. These patients had more frequently rate responsive function (19.7% vs 64.1%) and higher basic rate (median value 60 bpm vs 70 bpm) as compared to all other patients (p < 0.001). The CRT pacing percentage calculated over the first 2 months was slightly lower for perm-AF patients (median value 96.0% vs 98.8%, p < 0.001).

At 5-year appropriate shock incidence was 34.2% (95% confidence interval [CI], 25.1%-45.3%) for perm-AF and 19.9% (15.6%-25.1%) for all other patients. All-cause mortality was 27.7% (17.7%-41.8%) for perm-AF and 15.6% (12.2%-19.9%) for all other patients. 

The age- and sex-adjusted hazard ratio between perm-AF and all other patients was 1.81 (95% CI: 1.25-2.64, p = 0.002) for appropriate shock and 0.92 (95% CI: 0.57-1.50, p = 0.748) for all-cause mortality.

Conclusion

Although a higher incidence of appropriate shock, perm-AF at the time of CRT-D implantation was not associated with increased long-term mortality,

Abstract Figure. Appropriate shock and mortality
P365Does papillary muscle ablation affect mitral valve function: a single centre experience
Authors: Stassen J , Dilling D , Vijgen J , Schurmans J , Koopman P
Published: June 2020

Introduction

Ventricular arrhythmias from papillary muscles (PMs) often require extensive catheter ablation (CA). Not much is known about the mitral valve (MV) function after these extensive catheter ablations.

Purpose

The goal of this study was to determine the impact of papillary muscle CA on MV function. 

Methods

We retrospectively examined echocardiographic measurements in 21 patients with frequent premature ventricular contractions (PVCs) originating from the mitral PMs who underwent CA, dating from October 2012 till November 2018. We assessed MV function at baseline, 6 month and last follow-up. Degree of mitral regurgitation (MR) was graded as mild (ERO <0,2 cm2, regurgitation volume (RV) <30ml), moderate (ERO 0,2-0,4cm2, RV 30-59ml) or severe (ERO ≥0,4cm2, RV  ≥60ml). Significant MR was defined as a 2+ change.

Results

Mean age of the study population was 59,7 (27-80)years, 52,4% was female.

2 patients were known with ischemic heart disease. There was a family history of sudden cardiac death in 3 patients. Main symptoms at presentation were palpitations (66,7%), fatigue (33,3%), dyspnea (33,3%, all NYHA 2), dizziness (28,6%), angina pectoris (14,3%) and syncope (4,8%). Beta blocker (71,4%), flecaïnide (23,8%), amiodarone (9,5%), sotalol (4,8%) and propafenon (4,8%) were the most frequent medical therapies before CA.

Mean burden of PVC before ablation was 15 574 (2000-39700)/24h. In 28,6% non sustained VT was documented, 1 patient suffered a sustained episode of VT.  After ablation, mean burden of PVC was reduced to 1331 (0-14200)/24h. Redo ablation was necessary in 28,6% of patients. PVCs orginated from the anterolateral PM in 33,3% and from the posteromedial PM in 66,7%. Mean troponin release was 9.4 ± 5.3 µg/l, mean troponin hs (since 2016) was 1591.0 ±658.6ng/ml. CMR was done in 14/21 (66,7%) patients before CA. In 5 out of 14 patients (35,7%), delayed enhancement at the papillary muscles was noticed. In 5 patients without delayed enhancement, CMR was repeated after CA. In all these 5 patients, delayed enhancement was noticed at the level of the papillary muscles. 

At baseline, 15/21 had mild, 5/21 moderate and  1/21 severe MR. There was no significant chance in MR at 6m follow-up with 15/21 having mild and  6/21 moderate MR (p 0.58) with 1 patient having a significant MR 2+ change. At last follow-up (23.7 ± 22.6 months) there was also no significant chance in MR with 15/21 having mild and 6/21 moderate MR (p 0.58) without a significant MR 2+ change. 

Complications occurred in 1 patient (transient AV blok). No patients died during follow up. 

Conclusions

Although PM ablation was associated with time extensive ablation, significant troponine release and documented delayed enhancement on post ablation MRI, there was no risk of additional valvular dysfunction after CA in this study. Larger studies will be necessary to confirm these findings.
862Syncav with multipoint pacing improves acute left ventricular hemodynamics
Authors: Chow A , Waddingham P , Betts T , Mangual J , Badie N , Mcspadden L , Pappone C , Calo L , Leyva F , Thibault B
Published: June 2020

Funding Acknowledgements

Abbott

Introduction

SyncAV has been shown to improve electrical synchronization by automatically adjusting atrioventricular delay (AVD) according to the intrinsic atrioventricular conduction time. Additional incremental electrical synchronization may be gained by the addition of second left ventricular (LV) pulse with MultiPoint Pacing (MPP). While the electrical synchronization benefits of SyncAV have been previously explored, there has been no assessment of the acute hemodynamic impact of SyncAV with or without MPP.

Objective

 Evaluate the acute LV hemodynamic impact of SyncAV with and without MPP.

Methods

Heart failure patients with LBBB and QRS duration (QRSd) > 140 ms undergoing CRT-P/D implant with a quadripolar LV lead were enrolled in this prospective study. A guidewire or catheter with pressure transducer was placed in the LV chamber and the maximum pressure change (dP/dtmax) was recorded during the following pacing modes:  intrinsic conduction, conventional biventricular pacing with SyncAV (BiV + SyncAV), and MPP with SyncAV (MPP + SyncAV). Twelve-lead surface ECG was used to determine the patient-tailored SyncAV offset that minimized QRSd.

Results

Twenty-seven patients (67% male, 44% ischemic, 30 ± 7% ejection fraction) completed the acute recordings. Relative to the intrinsic QRSd of 163 ms, BiV + SyncAV reduced QRSd by 21.5% to 124 ms (p < 0.001 vs. intrinsic) and MPP + SyncAV reduced QRSd by 26.6% to 120 ms (p < 0.05 vs. BiV + SyncAV). Beyond electrical synchronization, SyncAV significantly improved acute hemodynamics. Relative to the intrinsic dP/dtmax of 842 mmHg/s, BiV + SyncAV elevated dP/dtmax by 6.3% to 900 mmHg/s (p < 0.001 vs. intrinsic) and MPP + SyncAV elevated dP/dtmax by 8.8% to 926 mmHg/s (p < 0.005 vs. BiV + SyncAV). Despite both QRSd and dP/dtmax improvement with SyncAV and MPP, correlation between electrical and hemodynamic measurements was poor (R2 = 0.0 for BiV + SyncAV, R2 = 0.1 for MPP + SyncAV).

Conclusion

SyncAV may significantly improve acute LV hemodynamics in addition to electrical synchrony in LBBB patients. Further incremental improvement was achieved by combining SyncAV with MPP.

Abstract Figure.
1265The results of whole exome sequencing in patients with bradyarrhythmias
Authors: Polyakova E , Shcherbakova N
Published: June 2020

Introduction. Sick sinus syndrome (SSS) and atrioventricular block (AVB) are life-threatening cardiac arrhythmias, that sometimes can manifest itself with syncope and needs a pacemaker implantation even in children. Sometimes, SSS and AVB are accompanied by structural heart diseases such as septal defects, cardiomyopathies, but often the heart is structurally normal. Some genes associated with bradyarrhythmias are well known. At the same time, the etiology of the SSS is unidentified and may be genetic caused in 50% of patients with SSS. There are no studies on the prevalence of with bradyarrhythmia-associated mutations in children.

The purpose of our work is to identify and study the types of mutations associated with SSS and AVB in children.

Methods. We included in the study 15 patients (27% boys) with severe SSS and AVB, from the database of the Russian Pediatric Arrhythmia Center. 11 were the probands and 4 - family members.  Personal and family history, physical examination, including ECG, stress test, Holter monitoring, ECHO and other tests, and whole exome sequencing were made. The average age was 14.1 ± 4.5 (from 2 to 17).

Results.  In 30% (5 pts) there was the combination of with bradyarrhythmias and structural heart disease. 7 pts (47%) had syncope, 4 pacemakers were implanted. 10 children (67%) had the genetic variants of genes associated with SSS and AVB: SCN5A, TNNI3K, KCNA5, TRPM4, ANK2 and others. Family history of cardiac diseases was positive in 5 probands; 2 probands had family members with implanted pacemakers. In 3 pts were likely pathogenic variants and in 7 pts - variants of unknown significance found.

Conclusion.  We found the genetic cause of bradyarrhythmias in 67% of children. Further research and larger patient samples are required to study the prevalence of genetic types of and show the correlation of the genotype with the clinical prognosis.

In addition, our work will enable practitioners to identify children from families with family forms of SSS, AVB and sudden cardiac death. Further research can help us determine the criteria for selecting children for genetic testing.
P318Positive left ventricular remodeling after TAVI assessed by high resolution electrocardiography
Authors: Vitez L , Krajacic B , Starc V , Bunc M
Published: June 2020

Introduction

Transcatheter aortic valve replacement (TAVI) is a novel treatment method for sever aortic stenosis that has a positive impact on reverse left ventricular (LV) remodeling. The morphology and function of the LV can be assessed by transthoracic echocardiography (TTE) and high resolution electrocardiography (HR-ECG). 

Purpose

 

The purpose of our study was to investigate whether morphological and functional myocardial changes after TAVI seen on TTE can be tracked by advanced ECG parameters using HR-ECG.

Methods

Consecutive TAVI patients with transfemoral approach were included in this pilot prospective study. A 5 minute HR-ECG and TTE were performed before and one year after TAVI. Spatial QRS vector amplitude (3D_QRSm), total 12-lead QRS amplitude (12leadV), spatial QRS-T angle (QRST_aM) and spatial ventricular gradient (SVG) were measured using HR-ECG and interventricular septum diastolic diameter (IVSd), left posterior wall diameter (LVPWd), left ventricular ejection fraction (LVEF) and tissue Doppler peak septal systolic velocity (Sm) were obtained by TTE. Student"s test was used for pairs to analyze the differences in sets of variables before and after TAVI and Pearson correlation coefficient to analyze the relationship between TTE and HR-ECG parameters. 

Results

15 patients (5 male; 33.3%) were included in the study. At one year follow-up we found statistically significant reduction in LV wall thickness and increase in LVEF (61.6 ± 6.50 % vs. 66.9 ± 7.84 %, p = 0.043). In the subgroup with narrow QRS (8 patients), we found a statistically significant correlation between change of left posterior wall thickness (deltaLVPW) and spatial QRS vector amplitude (delta3D_QRSm) (r = 0.795; p = 0.018), and between change of left ventricular ejection fraction (deltaLVEF) and spatial QRS-T angle (deltaQRST_aM) (r = 0.604; p = 0.038). No significant correlations were found in the subgroup of patients with wide QRS complex. 

Conclusions

Our pilot study showed that morphological and functional myocardial changes after TAVI in patients with narrow QRS complex can be followed with advanced ECG parameters using HR-ECG. HR-ECG could prove to be a simple and inexpensive method of follow-up after TAVI in patients with narrow QRS. To ascertain the usefulness and reliability of HR-ECG, a study on a larger number of patients would be required.
P1166Women as candidates for CRT: Are they less but better?
Authors: Aguiar-Ricardo I , Nunes-Ferreira A , Rigueira J , Rdrigues T , Cunha N , Antonio P S , Morais P , Pereira S C , Bernardes A , Santos I , Magalhaes A , Neves H , Pinto F J , De Sousa J , Marques P
Published: June 2020

Introduction

 Women have been under-represented in trials of cardiac resynchronization therapy (CRT).  Most available data suggest that CRT has a greater clinical benefit in women than in men. However, further studies are needed to investigate the exact reasons for these results.

Purpose

To compare the prognostic impact and response rate of CRT in women and man.

Methods

Prospective study, single-center study that included pts undergoing CRT implant from 2015 to 2019. Clinical and echocardiographic evaluation were made before CRT implant and between 6-12 months post-implant. Pts with EF elevations≥10% or LV end-systolic volume (ESV) reductions≥15% were classified as responders. Patients with EF elevations ≥ 20% or ESV reductions≥30% were classified as super-responders. All the parameters were compared between women and man. Prognostic impact of CRT was evaluated as total mortality by the Cox regression and Kaplan-Meier methods.

Results

From 2015-2019, 561 patients were submitted to CRT implant with a follow-up duration of 18.9 ± 15.8 months. From these 148 (26.4%) were female (mean age 72.2 ± 10 years, 22.4% ischemic, LVEF < 30% in 70.2%). The cardiovascular risk factors and comorbidities were similar in both populations (women and men). In the female group, dilated cardiomyopathy was more frequent than in men (71% vs 50.8%, p < 0.01), with ischemic heart disease being the second most frequent etiology of heart failure.

The frequency of LBBB was similar in both groups (63.9% in women and 57.0% in men, p = NS) however the QRS duration was higher in women (164 ± 17 vs 160 ± 24, p = 0.017). The baseline mean EF was similar (30.5 ± 10.3ms in women and 30.3 ± 11.4ms in men) but the ESV was lower (109.7 ± 59.9 vs 138.4 ± 64.6, p < 0.001).

The prevalence of complications and need for surgical revision were similar in both groups.

The rate of CRT responders was similar in both groups, although tendentially higher in women (64.3% in women vs 55.2% in men, p = NS). On the other hand, super-responder rate was statistically significant (38% in women vs 25.1% in men, p = 0.004). The long-term survival was similar in both groups.

Conclusion

The rate of super-responders was higher in women than in men. This may be explained by the higher prevalence of dilated cardiomyopathy in this subgroup of patients and by the fact that women have smaller hearts and a larger QRS duration at baseline, most likely to have a real LBBB. Long-term mortality of CRT was not gender related

Abstract Figure. Long-term survival by gender
1244Feasibility, safety and efficacy of tailoring ablation index to left atrial wall thickness (lawt) during atrial fibrillation ablation. The Ablate By-LAW Study
Authors: Teres C , Jauregui B , Soto-Iglesias D , Ordonez A , Chauca A , Ramirez C , Oller G , Jornet A , Palet J , Padro J , Maldonado G , Panaro A , Carballo J , Penela D , Berruezo A
Published: June 2020

Funding Acknowledgements

Dr Teres was funded by Swiss Heartrhythm Foundation

Introduction

Circumferential pulmonary vein isolation (PVI) has become a mainstay in the treatment of atrial fibrillation (AF). The utility of ablation index (AI) to dose radiofrequency delivery for the reduction of AF recurrences has already been proven with a target AI ≥ 400 at the posterior wall and ≥550 at the anterior Wall. Nevertheless, the left atrial wall is a thin, heterogeneous structure with an important inter and intra-patient variability of LAWT.

Objective

To determine if adapting AI to atrial wall thickness (AWT) is feasible, effective and safe during AF ablation.

Methods

Single-Center study that included 80 consecutive patients referred for a first paroxysmal AF ablation that was performed with a single catheter approach with the intention to reduce vascular access complication rate. All patients had a MDCT prior to the ablation procedure. LAWT maps were semi-automatically computed from the MDCT as the local distance between the LA endo and epicardium. All procedures were performed under general anesthesia with a high-rate low-volume ventilation protocol for obtaining higher catheter stability. The transeptal puncture was TEE-guided. During the procedure, the WT map was fused with the LA anatomy using CARTO-merge. LAWT was categorized into 1mm-layers and the AI was titrated to the local atrial WT as follows: Thickness < 1 mm (red): 300; 1-2 mm (yellow): 350; 2-3 mm (green): 400; 3-4 mm (blue): 450; > 4 mm (purple): 450 (Figure). Maximal inter-lesion distance was set at 6 mm. VisiTag settings were: catheter position stability: minimum time 3 s, maximum range 4 mm; force over time: 25%, minimum force 3 g; lesion tag size: 3 mm. Respiration training was not possible due to the high catheter stability.  The circumferential ablation line was designed in a personalized fashion to avoid thicker regions.

Results

80 patients [41 (51,2 %) male, age 60± 11 years] were included. Mean LVEF was 59 ± 5 %, Mean LA diameter 39,1 ± 5,8 mm, Mean LAWT was 1.36 ± 0.63 mm. Mean AI was 352 ± 36 on the RPVs and 356 ± 36 on the LPVs. Procedure time was 60,0 min (IQR 51-70). Fluoroscopy time was 58,5 s (35-97,5). First pass isolation was obtained in 72 (90%) of the RPVs and 75 (93,8%) of the LPVs.

Conclusions

the present study, assessing a novel, personalized protocol for radiofrequency titration during atrial fibrillation ablation, shows a high rate of first pass isolation with a lower need for RF energy delivery and lower procedure requirements, as compared to previous PV ablation protocols. Further studies are needed to evaluate the long-term results of this approach.

Abstract Figure. LAWT-map Visitag points with tailored AI
659Left atrial wall thickness evaluation during atrial fibrillation redo procedures
Authors: Teres C , Soto D , Jauregui B , Penela D , Ordonez A , Chauca A , Ramirez C , Oller G , Jornet A , Palet J , Santana D , Panaro A , Maldonado G , Carballo J , Berruezo A
Published: June 2020

Funding Acknowledgements

Dr Teres was funded by Swiss Heartrhythm Foundation

Introduction

pulmonary vein (PV) reconnections due to gaps on circumferential ablation lines are responsible for atrial fibrillation recurrences after catheter ablation. We sought to analyze the local left atrial wall thickness (LAWT) of PV line gaps at AF redo ablation during real-time catheter positioning. LAWT was measured on the MDCT 3D reconstruction and fused with the LA anatomy using CARTO-merge.

Objective

To analyze the relationship between local reconnection gaps and the LAWT during AF redo procedures.

Methods

Single-Center cohort study that included 41 consecutive patients referred for AF redo procedure. All patients had a MDCT prior to the ablation procedure. LAWT maps were semi-automatically computed from the MDCT as the local distance between the LA endo and epicardium. Each PV line was subdivided into 8 segments and mean LAWT was computed. During the procedure, the local gap was defined as the earliest activation site at the reconnected segment of the circumferential PV line (Figure 1A & 1B).

Results

41 patients [31 (75.6%) male, age 60 ± 10 years] were included. Mean LAWT was 1.36 ± 0.20 mm. Mean PV circumferential line WT was higher in left PVs than in the right PVs 1.68 ± 0.57 vs. 1.31 ± 0.39 mm p < 0.001 respectively. Mean WT of the reconnected points was 44% higher than the mean WT of the segment where the reconnection was located. Mean reconnection point WT was at the 87th percentile of the circumferential line in the LPVs and at the 76th percentile in the RPVs. The reconnected point WT was higher in the LPVs than RPVs 2.13 ± 1.14 vs. 1.47 ± 0.48 mm p < 0.001 respectively.  The most frequent location for reconnections was the left anterior carina (71%), with a mean WT of 2.24 ± 0.91mm; and the right anterior carina (56%) with a mean WT of 1.57 ± 0.62mm (Figure 2A & 2B).

Conclusions

Reconnection points were more frequently present in the thicker segments of the PV circumferential line. The most frequently reconnected segment was the anterior carina in both right and left PVs. Atrial wall thickness maps derived from MDCT are useful to guide AF redo procedures.

Abstract Figure. 1) Activation & WT map; 2) Segment WT
232Accessory pathway ablation in adults: estimated additional cancer risk depending on the mapping and ablation strategy
Authors: Bastian D , Buia V , Rordorf R , Petracci B , Walascheck J , Vicentini A , Muca M , Savastano S , Sanzo A , Rittger H , Vitali Serdoz L
Published: June 2020

Introduction

Catheter ablation is the treatment of choice for accessory pathways (AP) in high risk patients and it´s usually performed under fluoroscopy guidance (reported X-Ray time:16 -38min).Radiation exposure is associated with an increased incidence of dermatitis,gene defects, cataract and malignancy.3-D mapping systems(EAMS) can reduce fluoroscopy exposure.

Purpose

To evaluate the additional cancer risk throughout life in 2 homogeneous adult populations of high-risk APs treated either with conventional fluoroscopically guided ablation (CFA) or with an EAM- and echocardiography(TEE or ICE)guided minimally fluoroscopic ablation approach (MFA).Methods:  2 Center study, 60 consecutive pts enrolled; 31pts underwent CFA at IRCCS Policlinico san Matteo (Pavia) and 29 pts underwent EAM guided MFA at Klinikum Fuerth between 01/2016 and 09/2019.The age and gender-adjusted cancer risk was calculated following Monte Carlo code,according to Biological Effects of Ionizing Radiation (BEIR VII) empirical risk models. 

Results

The estimated additional cancer risk throughout life gained with a single ablation procedure was significatively different between groups:0.18% in CFA compared to 0.001% in MFA group(P < 0.001).The maximum estimated additional cancer risk for a patient undergoing CFA was 1%.10 out of 29 MFA procedures(35%)were successfully performed with zero fluoroscopy. Conclusions:Our small study demonstrates that an echocardiography/EAM guided approach allows safe AP ablation adding a significantly reduced estimated cancer risk compared to CFA in young adults,a population sensitive to X-ray exposure regarding the stochastic risk of developing malignancies.This finding strongly supports the recommendation for a routine use of EAMS in AP ablations,including appropriate reimbursement.

Results Conventional fluoroscopic approach Minimal fluoroscopic approach p Patient (N) 31 29 n.s. Age (Y) 43.7 ± 14 44.7 ± 17 n.s. Right AP 10 6 n.s. Left Ap 21 23 n.s. Transeptal Access 20 22 n.s. Complications 1 (3%) 0 n.s. DAP (µGy*m2) 15252+/-11132 56.8+/-135.6 0.000 Effective Dose (mSv) 30.35+/-27.7 0.09+/-0.28 0.000. Additional Cancer Risk 0.18% 0.001% >0.001 N, number; Y, years; AP, Accessory Pathway.
P539Comparative analysis of patients with cardiac resynchronization therapy depending on septal flash
Authors: Shirokov N , Kuznetsov V , Soldatova A , Malishevskii L , Krinochkin D
Published: June 2020

Background

Mechanical dyssynchrony (MD) and superresponse (SR) to cardiac resynchronisation therapy (CRT) relationship is still debated.

Aim

To assess clinical and morpho-functional features of the heart in patients with congestive heart failure (CHF) after cardiac resynchronization therapy (CRT) depending on septal flash (SF).

Materials and methods

The study enrolled 60 patients (92.0% men, 8.0% women; mean age 54.5 ± 10.4 years; 70.0% had left bundle branch block (LBBB) with II-IV NYHA functional class CHF. SF (mechanical anomaly of interventricular septum (IVS) movement) is determined according to speckle tracking echocardiography (STE) and tissue Doppler imaging (TDI). Patients were divided into two groups: with SF (I group, n = 10) and without SF (II group, n = 50).

Results

At baseline the groups did not differ in main clinical characteristics including QRS width and LBBB. Mechanical interventricular delay was higher in group I (65.5 ms [53.5;95.5] vs 31.0 ms [15.0;64.5]; р=0.026). Basal segment of IVS longitudinal strain (LS) delay by STE (257.5 ms [156.3;293.8] vs 323.5 ms [262.5;377.8]; р=0.024) and LS delay by TDI (204.0 ms [170.8;260.3] vs 434.0 ms [370.0;489.0]; р<0.001) were significantly lower in group with SF. According to logistic regression a combination of LS apical segment of IVS by STE (HR 0.607; 95% Cl 0.369 – 0.989; р=0,048) and LS delay basal segment of IVS by TDI (HR 0.969; 95% Cl 0.0945 – 0.993; р=0.011) had a relationship with SF. According to ROC analysis sensitivity and specificity of this model in SF definition in patients with CRT were 87.5% and 86.5% (AUC = 0.939; p < 0.01). Mean changes in LV ESV (52.0 ml [32.5;72.8] vs 19,0 ml [1.3;40.0]; р=0.002) and LV ejection fraction (EF) (13.0% [5.5;18.8] vs 4.0% [2.0;9.0]; р=0.002) were significantly higher in patients with SF. All patients in group I had a super-response to CRT (ESV LV decrease ≥30%); 42.0% patients in group II were superresponders (р<0.001).

Conclusion

SF could be determined by STE and TDI. SF is associated with severe mechanical interventricular dyssynchrony and superresponse to CRT. Patients with SF have significantly better LV EF dynamics after CRT.

Abstract Figure. Septal Flash in patient with SR to CRT
P951Autonomic nervous function and excitability of the accessory pathway in pediatric patients with Wolff-Parkinson-White ECG
Authors: Galli A , Lippolis M , Barbolini E , Belmonte M , Ambrosini F , Gherbesi E , Chierchia G B , De Asmundis C , Lombardi F
Published: June 2020

Abrupt loss of preexcitation identifies low-risk Wolff-Parkinson-White (WPW). We hypothesize that the autonomous nervous system (ANS) modulates the conduction of the accessory pathway (AP).

PURPOSE

To compare heart rate variability (HRV) in children with (WPWi) and without (WPWp) intermittent preexcitation. 

METHODS

The study conforms to the Declaration of Helsinki. 

18 WPW children and controls performed ECG Holter for HRV analysis. Intermittent preexcitation was defined as abrupt loss of WPW pattern. Kolmogorov-Smirnov test confirmed normal distribution of data. T-test and Fisher"s exact test were used for continuous and categorical variables. Multivariate regression excluded the effect of potential confounders (figure 1 shows correlation between HRV and HR). 

RESULTS

WPWi (11/18, 61.1%) have higher HRV as compared with WPWp. Despite WPWp patients are younger, with higher HR, corrected multivariate analysis confirmed significant differences (table 1), also between WPW patients and controls. 

CONCLUSIONS

WPW patients have lower HRV. WPWp may have worst autonomic control to the excitability of AP.

Table 1 WPW (n = 18)A WPWi (n = 11)B WPWp (n = 7)C Controls (n = 18)D P value A vs. D P value B vs. C P value B vs. D P valueC vs. D Age 7.6 ± 4 10.1 ± 4.2 4.1 ± 2.9 7.8 ± 4.7 0.9 <0.01 0.1 0.03 24 hours mean HR 92.8 ± 15.9 81.1 ± 11.2 104.9 ± 12.6 90.3 ± 16.5 0.7 <0.01 0.03 0.07 pNN50 20 ± 11.4 30.5 ± 11.8 14.7 ± 9.9 24.3 ± 13.4 <0.001 <0.001 <0.001 <0.001 RMSSD 53 ± 19.1 68.8 ± 21.4 44.6 ± 14.7 59.4 ± 22.2 <0.001 <0.001 <0.001 <0.01 ASDNN 64.9 ± 21.1 78.4 ± 20.7 48.8 ± 11.8 66.9 ± 22.9 <0.001 <0.001 <0.001 <0.001 SDANN 108.2 ± 39.8 127.9 ± 36 77.5 ± 16.9 108.3 ± 38.8 <0.001 <0.01 <0.001 <0.01 VLF 7.4 ± 0.8 7.8 ± 0.4 6.9 ± 0.5 7.5 ± 0.6 <0.001 <0.001 <0.001 <0.001 LF 6.8 ± 0.8 7.3 ± 0.4 6.4 ± 0.4 6.9 ± 0.6 <0.001 <0.001 <0.001 <0.001 HF 6.6 ± 0.8 7.1 ± 0.7 6.2 ± 0.6 6.7 ± 0.8 <0.001 <0.01 <0.001 <0.01 LF/HF 1.4 ± 0.8 1.4 ± 0.7 1.4 ± 0.6 1.4 ± 0.6 0.2 0.3 0.05 0.7 VarIndex% 4.8 ± 1.4 5.8 ± 1.2 4.4 ± 1.4 5.3 ± 1.4 <0.001 <0.01 <0.01 <0.01 Total Power 8.2 ± 0.7 8.6 ± 0.4 7.8 ± 0.4 8.3 ± 0.6 <0.001 <0.001 <0.001 <0.001 Frequent SVB 2 (11%) 1 (9.1%) 1 (14%) 0 0.5 1.0 0.4 0.3 SVT 1 (5.6%) 1 (9.1%) 0 0 n.a. n.a. n.a. n.a. P values from multivariate analysis and t-test for age and HR. HR: heart rate; WPWi: intermittent preexcitation; WPWp: persistent preexcitation; VarIndex%: variability index (%); SVB: supraventricular beats; SVT: supra ventricular tachycardia. Values are expressed as mean ± SD for age, HR and time domain variables (ms). Variables in the frequency domain are expressed as ln. P <0.05: significant.

Abstract Figure 1
P436The impact of filter settings on morphology of unipolar fibrillation potentials
Authors: Starreveld R , Knops P , Roos-Serote M , Kik C , Bogers A J J C , Brundel B J J M , De Groot N M S
Published: June 2020

Funding Acknowledgements

N.M.S. de Groot, MD, PhD was supported by CVON-AFFIP (914728), NWO-Vidi (91717339) and Biosense Webster USA (ICD 783454).

Background

Using unipolar atrial electrogram morphology as guidance for ablative therapy is regaining interest. Although standardly used in clinical practice during ablative therapy, the impact of filter settings on morphology of unipolar AF potentials is unknown.

Purpose

This study aims to elucidate consequences of high-pass, low-pass and notch filtering on unipolar atrial fibrillation (AF) potentials.

Methods

Thirty different filter settings were applied to high-resolution epicardial AF potentials recorded from ten patients. . Local activation times were determined by marking deflections with slope ≤-0.05mV/ms and amplitude ≥0.3mV. Fibrillation potentials were analyzed for peak-to-peak amplitude (mV), number of deflections (f) and fractionation delay time (FDT, interval between first and last deflection), and classified as single potential (SP, f = 1), double potential (DP, f = 2) or complex fractionated potential (CP, f ≥ 3).

Results

In total, 3000 seconds of AF recordings were analyzed, containing 255,7045 fibrillation potentials. Changing high-pass filtering from 0.5 up to 100 Hz decreased the number of detected fibrillation potentials (with 25-65%), median deflection amplitude (min-max 0.59-0.96 to 0.44-0.57 mV), percentage of DP (25.8-32.9 to 22.5-31.6%) and CP (15.9-36.0 to 7.3-37.8%) as well as median FDT (16-25 to 11-15 ms) (all p < 0.01). Gradually changing low-pass filtering from 400 Hz to 20 Hz induced an exponential decrease in fibrillation potentials (to 0%), percentage of DP (25.8-32.9 to 0%) and CP (15.9-36.0 to 0%), whereas deflection amplitude, percentage of SP and median FDT exponentially increased (0.59-0.96 to 1.82-2.39 mV, 36.1-57.6 to 100%, 16-25 to 33-38 ms, respectively) (all p < 0.01). Notch filtering at 50 Hz decreased the number of detected fibrillation potentials (with ∼1%), median deflection amplitude (0.59-0.96 to 0.59-0.95 mV) (both p < 0.01), whereas the percentage of CP increased (15.9-36.0 to 16.2-37.0%, p = 0.016).

Conclusions

Filtering significantly impacted  of unipolar fibrillation potentials and decreased the number of detected potentials, becoming a potential source of error in identification of LATs, low-voltage areas, fractionated potentials and thus ablative targets during mapping.

Potentials (%) Amplitude (mV) SP (%) DP (%) CFP (%) FDT (ms) Default (0.5-400 Hz) 100 0.59-0.96 36.1-57.6 25.8-32.9 15.9-36.0 16.0-25.0 High-pass filtering Decreased Decreased Increased Decreased Decreased Decreased Low-pass filtering Decreased Increased Increased Decreased Decreased Increased Notch filtering Decreased Decreased p = NS p = NS Increased p = NS Impact of filtering on morphology parameters

Abstract Figure. Impact of filtering on AF morphology
40Lateral left ventricular lead position and long interlead electrical delay predict long-term all-cause mortality in cardiac resynchronization therapy patients
Authors: Behon A , Schwertner W R , Merkel E D , Kovacs A , Kutyifa V , Lakatos B , Zima E , Geller L , Kosztin A , Merkely B
Published: June 2020

Background

There is limited data on the association of left ventricular (LV) lead position and long-term clinical outcome in patients after cardiac resynchronization therapy (CRT).

Purpose

We evaluated the mid-term echocardiographic response and long-term all-cause mortality of patients who underwent CRT implantation by LV lead non-apical positions and further characterized them by right to left ventricular, interlead electrical delay (IED).

Methods

In our retrospective registry patients after CRT implantation between 2000 and 2018 were registered. Those with non-apical LV lead location were classified into anterior (n = 111), posterior (n = 652), and lateral (n = 1373) positions. Primary endpoint was all-cause mortality assessed by univariate- and Cox multivariate analyses. Secondary endpoint was echocardiographic response within 6 months after CRT implantation.

Results

From 2136 patients 1180 (55.2%) reached the primary endpoint during the mean follow up time of 4.5 years. Univariate analysis showed patients with lateral position had significantly better outcome compared to others (HR 0.80; 95% CI: 0.71-0.90; p < 0.01), which was also confirmed by Cox multivariate analysis (HR 0.69; 95% CI: 0.50-0.93; p = 0.02) after adjusting for relevant clinical covariates such as IED and LBBB. The median value of IED was 106 (89/124) ms in the total patient cohort, which was significantly longer in the lateral group [anterior 80 (60/100) ms vs. lateral 110 (91/128) ms vs. posterior 100 (85/120) ms; p< 0.01]. When echocardiographic response was further evaluated in patients with lateral position, those with an IED longer than 110 ms (ROC AUC 0.64, 95% CI: 0.54-0.74; p = 0.01) showed the greatest benefit within 6 months.

Conclusions

After CRT implantation the most beneficial outcome was associated with lateral left ventricular lead location, moreover the greatest echocardiographic response was found when interlead electrical delay was longer than 110 ms in this group.

Abstract Figure. All-cause mortality of total cohort
P984Proof of endo-epicardial asynchrony of the left atrial wall in humans
Authors: Kharbanda R , Kik C , Knops P , Bogers A J J C , De Groot N M S
Published: June 2020

Funding Acknowledgements

Prof. Dr. NMS de Groot is supported by funding grants from CVON-AFFIP (914728), NWO-Vidi (91717339), Biosense Webster USA (ICD 783454) and Medical Del

Introduction

Treatment of atrial fibrillation (AF) is still suboptimal as mechanisms underlying AF initiation and persistence are incompletely understood. Endo-Epicardial asynchrony (EEA) plays an important role in AF persistence and has so far only been demonstrated in the right atrium (RA).

Purpose

To investigate whether EEA also exists in the thin walled left atrium (LA) and to measure the maximal degree of EEA between the endo- and epicardial layers during sinus rhythm (SR).

Methods

Simultaneous endo-epicardial mapping of the LA was performed during SR in 3 male patients (73 ± 1.5 years) with history of paroxysmal AF undergoing cardiac surgery including rhythm surgery and LA appendage amputation. Simultaneous endo-epicardial mapping was performed with a mapping clamp containing two electrode arrays of 8x16 electrodes (diameters: 0.4mm, interelectrode distance: 2mm) positioned exactly opposite to each other. The mapping clamp was introduced through the LA appendage with its tip towards the superior pulmonary vein. Local endo-epicardial activation time differences were determined by selecting the median time delay within the exact opposite electrode and its 8 surrounding electrodes. The asynchrony map consisted of the maximum of 2 medians from direct opposite electrodes. EEA was defined as time differences ≥15ms. Conduction delay (CD) and conduction block (CB) were defined as differences in local activation times between neighboring electrodes of respectively ≥7 and ≥12ms.

Results

A total of 35 SR beats were analyzed. Mean total activation time of the whole endo-epicardial LA tissue was 42.4 ± 9.5ms and did not differ between both layers (epicardium: 31.2 ± 9.9ms; endocardium: 37.8 ± 10.3ms; P= 0.62). CD and CB were observed in respectively 3.2% and 6.3% at the epicardium and 3.3% and 3.0% at the endocardium. The lowest amount of CD (5.2%) and CB (0.3%) was observed in the patient who had his first AF episode only 11 days prior to surgery. Also, no EEA was present in this patient. In two patients with paroxysmal AF >6 months, the prevalence of EEA was respectively 2.7% and 41.4% and the degree of EEA ranged from 15 to 44ms. Interestingly, the patient with the highest degree of EEA was diagnosed with paroxysmal AF for almost 5 years (Figure 1).

Conclusion

Our data provides evidence for the existence of EEA in the human left atrium which appears to be already present during SR. Knowledge of EEA and the ability to stage AF based on the degree of EEA is essential for individualized and staged future therapy for AF.

Abstract Figure 1. The maximal degree of endo-epi
42When to implant CRT-P or CRT-D in the elderly?
Authors: Silverio Antonio P , Nunes-Ferreira A , Aguiar-Ricardo I , Rodrigues T , Rigueira J , Santos R , Cunha N , Couto Pereira S , S Morais P , Magalhaes A , Bernardes A , J Pinto F , De Sousa J , Marques P
Published: June 2020

Introduction

Cardiac resynchronization therapy (CRT) in elder patients is increasingly common. However, the decision to implant a device with defibrillator in these patients is often complex and it can be limited not only by the shorter life expectancy but also by a lower relative risk of arrhythmic compare to non-arrhythmic death due to other comorbidities. Thus, wether CRT is effective in an elderly population (≥75 years old), or if a defibrillator (CRT-D versus CRT-P) influences outcomes is a pivotal concern needing additional data.

Purpose

To compare the prognostic impact of CRT-P vs CRT-D in old patients (≥ 75 years old) and its impact in the response rate to CRT.

Methods

A prospective single-center study was conducted of patients indicated for a CRT implant since 2015. Demographic and clinical criteria were evaluated. Transthoracic echocardiography was performed before CRT implant and between 6-12 months post-implant. Patients with an ejection fraction (EF) elevation ≥ 10% or a LV end-systolic volume (ESV) reduction ≥ 15% were classified as responders. Patients with EF elevation ≥ 20% or LV ESV reduction ≥ 30% were classified as super-responders. Time to surgical revision and mortality were evaluated using the Cox regression and Kaplan-Meier methods. The decision to implant a CRT-P or CRT-D device was made according to clinical decision. Prognostic impact of CRT-P vs CRT-D was evaluated by comparing total mortality using the Cox regression and Kaplan-Meier methods.

Results

From 2015-2019, 566 CRTs were implanted (26.1% female, follow-up duration 18.9 ± 15.8 months). Among these patients, 53.5% had < 75 years old and 46.5% ≥ 75 years. Baseline clinical characteristics were similar, except for a higher prevalence of chronic kidney disease and atrial fibrillation in the elderly population. The proportion of CRT-D/CRT-P was different between these groups (p < 0.001): in the elderly group, more CRT-P were implanted (67.6% vs 32.4 CRT-D) and in the younger group more CRT-D were implanted (77.9% vs 22.1% CRT-P).

The prevalence of complications due to CRT implant was similar in the two groups (4.7% vs 4.2%, p = NS) but the need for surgical revision was less frequent in the elderly group (11.0% vs 5.7%, p = 0.03). The CRT response rate was equivalent in both groups (40.1% vs 59.9%, p = NS), as was the super-response rate (33% in young vs 26.5% in old patients, p = NS).

In the elderly population, the 4-year survival rate was similar between CRT-P and CRT-D patients (75.4% vs 79.8%).

Conclusion

Patients older than 75 years old have similar benefits from the CRT as patients < 75 years, with equivalent response rates to CRT. However, judging from the similar prognostic impact of CRT-P vs CRT-D in this elder population, the implant of a defibrillator should be personalized.