bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of wavefront propagation speed on the right ventricular outflow tract: deceleration zones associated with the presence of low voltage areas
Authors: Parreira A , Carmo P , Mesquita D , Marinheiro R , Goncalves A , Marinescu C , Farinha J , Esteves A , Amador P , Lopes A , Fonseca M , Cavaco D , Galvao Santos P , Galvao Santos P , Adragao P
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background and aims

Activation wavefront is rapid and uniform in normal myocardium. Fibrosis is associated with deceleration zones (DZ) and late activated zones. The presence of low voltage areas (LVAs) in the right ventricular outflow tract (RVOT) of patients with premature ventricular contractions (PVCs) from this origin has been described previously. The aim of this study was to evaluate in sinus rhythm, the RVOT endocardial activation duration (EAD) and the presence of DZs, in patients with PVCs and in controls.

Methods

Consecutive patients with frequent (>10.000/24 h) idiopathic PVCs with inferior axis subjected to ablation that had an activation and voltage map of the RVOT performed in sinus rhythm. A control group of patients without PVCs that underwent ablation of supraventricular arrhythmias was also studied. Patients with structural heart disease, previous ablation or conduction disease were excluded. The RVOT EAD was measured as the time interval between the earliest and the latest activated region. Also evaluated the number of 10 ms isochrones throughout the RVOT and the maximal number of 10 ms isochrones within 1 cm, and a DZ was defined as a zone with > 3 isochrones within 1 cm. Low voltage areas (LVA) were defined as areas with local electrogram amplitude <1.5 mV.

Results

42 patients, 29 in the PVC group and 13 control subjects. The site of origin of the PVCs was the RVOT in 23 patients and the LVOT in 6. The characteristics of the two groups are displayed in the Table. Patients with PVCS had longer RVOT EAD, total number of isochrones and presence of DZ was also significantly higher (See table).  LVAs were more frequent in PVCs from the RVOT than from the LVOT (83% vs 33%, p = 0.033). Patients with LVA had longer EAD 60 (52-67) vs 36 (34-40) ms, p < 0.0001 (Figure A) and more DZ than patients without LVA 95% vs 0%, p < 0.0001 (Figure B and C).

Conclusions

The velocity of the wavefront propagation was slower and DZs were more frequently present in patients with PVCs and were associated with presence of LVAs. All sampleN= 42PVCsN = 29ControlsN = 13p-valueAge in years, median (Q1-Q3)56 (35-65)58 (38-66)53 (28-67)0.648Male gender, n (%)19 (45)14 (48)5 (39)0.401Nº points in the map, median (Q1-Q3)410 (338-589)467 (345-660)345 (333-465)0.056Activation duration in ms, median (Q1-Q3)41.8 (36-61)56 (41-66)39 (35-41)0.001Nº isochrones, median (Q1-Q3)4 (4-6)5 (4-6)4 (4-4)0.037Presence of DZs, n (%)20 (48)20 (69)0 (0)<0.0001Presence of LVAs, n(%)21 (50)21 (72)0 (0)<0.0001Abstract Figure.
Three-dimensional late gadolinium enhancement increases the diagnostic yield of cardiovascular magnetic resonance to detect low voltage in the right ventricular outflow tract
Authors: Parreira A , Ferreira A , Carmo P , Mesquita D , Marinheiro R , Amador P , Farinha J , Esteves A , Nunes S , Chambel D , Fonseca M , Cavaco D , Costa F , Marques H , Adragao P
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiac magnetic resonance (CMR) using late gadolinium enhancement (LGE) fails to detect scar tissue in patients with electroanatomical abnormalities and biopsy-proven structural heart disease. It has shown conflicting data regarding existence of structural abnormalities in patients with idiopathic premature ventricular contractions (PVCs) from the right ventricular outflow tract (RVOT). Three- dimensional (3D) LGE enables high-spatial resolution more appropriate to the thin-walled right ventricle than two-dimensional (2D) LGE.

Objective

Our aim was to evaluate if the use of 3D-LGE would improve the performance of CMR to detect low voltage areas in the RVOT of patients with PVCs.

Methods

Since May 2020 we performed 3D-LGE CMR in 11 consecutive patients that underwent ablation of frequent PVCs. A control group of 11 consecutive patients that underwent catheter ablation by the same operator and had a 2D-LGE CMR performed before ablation was also studied. All patients had normal 2D-LGE CMR. A 3D electroanatomical bipolar voltage map of the RVOT was performed in sinus rhythm (0.5 mV-1.5 mV colour display). Areas with electrograms <1.5 mV represented the LVA. The area adjacent to the pulmonary valve usually displays voltage between 0.5 and 1.5 mV and is classified as transitional-voltage zone. Presence of LVAs outside this transitional-voltage zone were estimated.  We compared the accuracy of CMR for detecting LVA in the two groups: 3D LGE and 2D LGE.

Results

The median number of points used for the voltage map was 344 (242-450). 18 patients (82%) displayed LVAs. The site of origin of the PVCs was the RVOT in 17 patients and the left ventricular outflow tract (LVOT) in 5. Comparison between groups is displayed in the table.  2D LGE CMR failed to demonstrate abnormalities of the RVOT in any of the patients that presented with LVAs. 3D CMR showed presence of fibrosis (Figure) in 3 out of 9 patients with LVAs (33%).

Conclusion

CMR using 3-D LGE techniques showed an increased power to diagnose structural abnormalities. This technique may be a better choice in initial stages of RVOT disease. All sampleN = 223D-LGE CMRN = 112D-LGE CMRN = 11p-valueAge in years, median (Q1-Q3)47 (35-68)62 (34-55)42 (34-55)0.243Male gender, n (%)8 (36)3 (27)5 (46)0.330PVCs RVOT/LVOT17/59/28/30.500Nº points in the map, median (Q1-Q3)344 (242-450)350 (259-450)300 (158-345)0.076Low voltage areas, n (%)18 (82)9 (82)9 (82)0.707Abstract Figure.
European early experience with a novel 3D mapping system
Authors: Deisenhofer I , Lengauer S , Telishevska M , Richter S , Rajappan K , Kottmaier M , Bertagnolli L , Moreno J , Hunter R , Tao C , Della Bella P
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Introduction

Catheter navigation and 3-dimensional (3D) cardiac mapping are critical for successful electrophysiological ablation procedures. A novel 3D mapping system received CE Mark in July 2020. The system offers two imaging modalities: magnetic-based (VoXel) and impedance-based (NavX). Real-time display of 3D location and catheter movements is achieved via a magnetic field frame and magnetic sensors with supplemental impedance data when operating in VoXel mode or primarily via an impedance field generated from surface electrodes in NavX mode. To address limitations in data collection commonly experienced during 3D mapping, a new respiratory compensation algorithm, patient movement detection module, and metal compensation algorithm have been developed to enable consistent data collection throughout the full respiratory cycle even in challenging cases and lab environments.

Purpose

To examine the clinical utility and procedural characteristics associated with the use of this novel 3D mapping system among participating centers.

Methods

Procedural data was collected in cases utilizing the newly cleared mapping system during the initial evaluation phase in Europe. Procedural characteristics recorded included indication for mapping and ablation, rhythm mapped, chambers mapped, and procedure time.

Results

Procedural data was collected from over 250 cases across 12 European centers. A total of 12 indications for mapping and ablation were represented including de novo and redo atrial fibrillation (paroxysmal, persistent, long-standing persistent), ventricular tachycardia (ischemic, non-ischemic) or premature ventricular contraction, and supraventricular arrhythmias (typical and atypical atrial flutter, atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia). Over 70% of the cases were performed in VoXel mode. Impedance mode was mostly used in SVT cases or when the case was intended to be completed with minimal fluoroscopy. The most commonly mapped rhythms were sinus rhythm during voltage mapping and atrial tachycardia. The majority of cases (over 65%) were completed under conscious sedation; general anesthesia was used in 20% of the cases (15% not reported). The respiratory compensation algorithm was utilized in over 90% of the cases. For cases in which pre-procedural computed tomography or magnetic resonance imaging were available, operators indicated that the model shape was accurate when compared to pre-procedural imaging in 96% of the cases performed in VoXel mode.

Conclusions

Initial European experience with this novel 3D mapping system included a wide variety of arrhythmias in the atria and ventricles. This new mapping system offered operators the flexibility to tailor to specific procedure needs with two imaging modalities which were both widely utilized.
Catheter ablation of long-standing persistent atrial fibrillation: the ugly type of AF?
Authors: Couto Pereira S , Rodrigues T , Brito J , Silverio Antonio P , Valente Silva B , Alves Da Silva P , Barreiros C , Lima Da Silva G , Carpinteiro L , Cortez-Dias N , Pinto FJ , De Sousa J
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Introduction

In atrial fibrillation (AF) patients (pts), catheter ablation (CA) by isolating pulmonary veins (PVI) is the most effective therapeutic option in order to maintain sinus rhythm. The success rate of CA relies on type and duration of AF, being more successful in pts with paroxysmal AF and presenting suboptimal success in pts with long-standing persistent AF (LSPAF, >12 months).

Purpose

To evaluate the success of AF ablation, particularly in LSPAF.

Methods

Single-center prospective study of pts submitted to CA between 2004 and 2020. The strategy, regardless of the type of AF, was based on PVI, complemented by cavo-tricuspid isthmus line (CTI) in pts with history of flutter. Additional CA strategies were selectively considered in pts with stable atypical flutter conversion, persistent triggers or no electrograms in the VPs. Pts were monitored with Holter/7-day event loop recorder (3, 6, 12 months and annually up to 5 years). Success was assessed from the 90th day after ablation, with the absence of recurrences of any sustained atrial arrhythmias (> 30 sec). Cox regression and Kaplan-Meier survival were used to compare the success of ablation as a function of the clinical type of AF.

Results

862 pts were submitted to AF ablation (67.3% male, mean age of 58 ± 0.41 years), including 130 pts (15.1%) with LSPAF, 63.3% with paroxysmal AF and 21.6% with short-duration persistent AF (SDPAF). In LSPAF, PVI was performed with irrigated catheter in 26.4%, PVAC in 39.5% and cryoablation in 34.1%. With a mean follow up period of 838 (IQ 159-1469) days, the 3-year success rate after a single procedure was 54.1% in LSPAF, compared to 72.4% in paroxysmal AF and 61.6% in SDPAF (LogRank - p < 0.0001 - figure 1). The risk of arrhythmic recurrence was 37% higher in patients with LSPAF comparing with other groups (HR 0.63 CI 95% 0.43-0.92, p 0.016).

However after a mean of 1.17 procedures/patients, the success difference between groups was not detect (LogRank – p = 0.112 – figure 2). With additional ablation procedures (REDO), the success rate at 3 years was 82.9% LSPAF pts, compared 88.2% in paroxysmal AF pts and 83.6% in SDPAF pts.

In LSPAF pts, different ablation techniques did not predict arrhythmic recurrence. Regarding comorbidities, higher prevalence of peripheral arterial disease (PAD, p = 0.005) a higher NT-proBNP (p = 0.006) and left auricular volume (p = 0.045) were associated with arrhythmic relapse.

Conclusions

AF ablation is more effective when performed earlier in the natural history of the disease. However, even in LSPAF pts, with additional procedures an acceptable rate of success can be achieve, independently from the ablation techniques. Abstract Figures 1 and 2: Success of AF ablation
A new approach to atrial flutter ablation using functional substrate mapping with wavefront discontinuity during sinus rhythm
Authors: Valbom Mesquita D , Parreira L , Farinha J , Marinheiro R , Amador P , Esteves A , Fonseca M , Chambel D , Goncalves A , Marques L , Caria R
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background

Ultra high-density (UHD) mapping allows accurate identification of local abnormal electrograms and low voltage within a small area range, allowing precise identification of reentry circuits. Areas with high isochronal density in a small area known as deceleration zones (DZ) are responsible for reentry.

Purpose

Identify the DZ and areas of low voltage in sinus rhythm (SR) and evaluate the feasibility of performing atrial flutter (AFL) ablation by targeting those zones.

Methods

We prospectively enrolled patients in SR referred for AFL ablation (either typical or atypical). An isochronal late activation mapping (ILAM) during SR with UHD catheter was performed, annotating latest deflection of local electrograms. DZ were defined as areas with >3 isochrones within 1cm radius, prioritizing zones with maximal density. Atrial flutter was then induced and ILAM during flutter was performed for comparison. Voltage mapping was also assessed (0.1-0.5mV). Ablation targeted DZ in SR that displayed the higher voltage. DZ in SR were compared to DZ in AFL. Number of radiofrequency (RF) applications needed to terminate AFL were assessed. After AFL termination, complete line of the slow conduction zone was completed, and pulmonary vein isolation (PVI) was done in case of left AFL. Categorical variables are presented in absolute and relative values and median and interquartile range were used for numerical variables, as well t-student test for correlation of numerical variables.

Results

We studied 6 AFL (4 atypical, 66.7%) in 5 patients, 2 male (40%), median age 70 (64- 72). UHD ILAM in SR with 2195 points (1212-2865) and 2197 points (1356-3102) in AFL (p = 0.62).  The UHD ILAM identified a median of (QR) DZ in SR, that colocalized with AFL isthmus and DZ in AFL in 100%. DZ were not always located in low voltage areas. Aiming at the higher voltage in the DZ terminated the AFL in all cases, with a median RF time of 38 (25-58) seconds and AFL was no longer inducible. However, according to protocol, the complete line of slow conduction zone was done, with a median RF time of 1049.5 (274-1194) seconds (p = 0,009).

Conclusions

Isochronal mapping in sinus rhythm with UHD catheters can display the functional substrate for reentry in AFL, allowing a substrate guided ablation in case of non-inducible AFL. Targeting the areas of high isochronal density, is effective in terminating AFL, obviating the need for extensive ablation. Abstract Figure.
Burden of arrhythmia in hospitalized patients with cannabis use related disorders: analysis of 2016-2018 national inpatient sample
Authors: Thyagaturu H , Thangjui S , Shrestha B , Shah K , Naik R , Bondi G
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Introduction

Cannabis is being more widely use as a recreational substance worldwide. There have been case reports and systematic review describing the association of cannabis use and cardiac arrhythmia (1).

Purpose

We sought out to measure the prevalence of different types of cardiac arrhythmia in hospitalizations associated with cannabis use disorder.

Methods

We queried January 2016 to December 2018 National Inpatient Sample (NIS) databases to identify adult (≥18 yrs) hospitalizations in the US with a diagnosis of cannabis use related disorders. Patients with an associated diagnosis of arrhythmias were also identified based on appropriate ICD-10 CM codes. We used the Chi-square test to evaluate the differences between binary or categorical variables, and Student’s t-test for continuous variables. Multivariate logistic regression was used in outcomes analysis to adjust for potential hospital and patient-level confounders (age, sex, race, diabetes, heart failure, chronic kidney disease, anemia, obesity, elixhauser co-morbidity index, hospital location, teaching status, bed size, income status and others). The discharge weights provided in the databases were used to calculate the national estimates. STATA 16.1 software was used to perform all statistical analysis.

Results

We identified 2,457,544 hospitalizations associated with cannabis use related disorders across three years. Of which, 187,825 (7.6%) were associated with any arrhythmia. We found that atrial fibrillation was the most associated arrhythmia. The complete list of types of arrhythmia and their prevalence are described in Figure-1. Patients with arrhythmia group were older (mean age 50.5 vs 38.3 yrs; P < 0.01) and had higher co-morbidity (% of >3 Elixhauser comorbidity score 94.1% vs 60.6%; P < 0.01). After adjusting for patient and hospital-level confounders, we observed arrhythmia group was associated with higher odds of in-hospital mortality compared to the group without arrhythmia [Odds Ratio (OR): 4.5 (4.09 – 5.00); P < 0.01]. We also observed statistically significant increase in hospitalization length of stay due to the status of any arrhythmia [5.7 vs 5.1 days; P < 0.01].

Conclusion

The prevalence of Afib is high in hospitalizations associated with cannabis use. Hospitalizations associated with cannabis use disorder and any arrhythmia are associated with higher in-hospital mortality and LOS. Therefore, all electrocardiograms should be scrutinized in hospitalized cannabis users. However, further prospective studies are necessary to endorse our study results. Abstract Figure.
Find me if you can: lessons learned using the novel cartofinder algorithm in a routine workflow for catheter ablation of atrial fibrillation
Authors: Sohns C , Bergau L , Unland R , Piran M , Chmelevsky M , El Hamriti M , Guckel D , Imnadze G , Khalaph M , Braun M , Sommer P
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background

CARTOFINDER allows for a simultaneous and automated detection of repetitive focal and rotational activations during electroanatomical mapping using a multi-electrode catheter in patients with atrial fibrillation (AF).

Aim

This study aimed to validate the CARTOFINDER algorithm for the detection of potential drivers for AF under routine clinical conditions and to access the effects of PVI and additional substrate modification on regions of interests (ROI) from CARTOFINDER mapping.

Methods

Forty-four consecutive patients underwent AF ablation for persistent AF using a 3D-mapping system with the novel integrated CARTOFINDER module. All patients presented with persistent AF and mapping was performed using a multi-electrode catheter. The ablation workflow was divided into the following steps: 1. 3D reconstruction of the right (RA) and left atrium (LA). 2. Identification of the individual ROIs separated for focal and rotational activity in the RA and LA. 3. Ablation index guided pulmonary vein isolation (PVI). 4. Repeat mapping for ROIs in the RA and LA. 5. Direct current electrical cardioversion. 6. Confirmation of persistent PVI and bipolar ultra-high density mapping of the RA and LA followed by substrate modification if there was evidence for local bipolar low-voltage in the LA.

Results

Acute PVI was achieved in all patients (100%). In 28% of these patients additional LA substrate modification was performed. AF termination was observed in 4 patients. Mean procedure duration was 137 ± 30 min, mapping time for ROIs in the RA was 8 ± 5 min and 11 ± 5 for the LA, respectively. A mean number of 149 ± 82 ROIs were revealed from CARTOFINDER. In the LA, focal activity was predominantly observed inside the LA appendage (LAA) and in close relationship to the pulmonary vein ostia. The majority of rotational activities was found along the mitral valve annulus. In the RA, the majority of ROIs was found at the septum and in close relationship to the RA appendage. During re-mapping for ROIs after AF ablation we observed the elimination of ROIs close to the linear ablation set for PVI. In addition, rotational activity could not be re-identified at repeat mapping.

Conclusions

ROIs could be discriminated and visualized utilizing CARTOFINDER in all patients. These ROIs might potentially be an additional and individual ablation target beyond PVI in patients with persistent AF.
Prevalence, management and impact of chronic obstructive pulmonary disease in atrial fibrillation: a systematic review and meta-analysis of 4,200,000 patients
Authors: Romiti GF , Corica B , Pipitone E , Vitolo M , Raparelli V , Basili S , Boriani G , Harari S , Lip GYH , Proietti M
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

AF-COMET Collaborative Group

Background

Multimorbidity is a major concern in patients with atrial fibrillation (AF). Among other diseases, the prevalence of chronic obstructive pulmonary disease (COPD) in these patients is unclear, and its association with adverse outcomes is often overlooked. Moreover, uncertainties on the treatment of patients with both AF and COPD still exist, and may lead to undertreatment.

Purpose

The aim of this study is to estimate the prevalence of COPD, and its impact on management and outcomes in patients with AF.

Methods

A systematic review and meta-analysis was conducted according to PRISMA guidelines. All studies reporting the prevalence of COPD in AF patients were included and pooled. Data on comorbidities, beta-blockers (BBs) and oral anticoagulant (OAC) prescription, and outcomes (all-cause death, cardiovascular death, ischemic stroke, major bleeding) were pooled and compared according to COPD status; the impact of BBs on outcomes in patients with COPD was also investigated. All analyses were performed using random-effect models; subgroup analysis and meta-regressions were also performed to account for heterogeneity.

Results

Among 46 studies, the pooled prevalence of COPD was 13% (95% Confidence Intervals (CI): 10-16%), with high heterogeneity between studies; significant differences were found according to geographical locations and definition of COPD. A multivariable meta-regression model which included age, female sex, history of hypertension, diabetes and chronic heart failure (CHF) was able to explain a significant proportion of the heterogeneity (R2 = 69.8%). COPD was associated with a higher prevalence of diabetes, coronary artery disease, CHF and stroke (Fig. 1, panel A), as well as higher CHA2DS2-VASc scores and age (Fig. 1, panel B), and lower probability of BB prescription (Odds Ratio (OR): 0.77, 95%CI: 0.61-0.98). Patients with COPD showed higher risk of all-cause death (OR: 2.22, 95%CI: 1.93-2.55), cardiovascular death (OR: 1.84, 95%CI: 1.39-2.43) and major bleeding (OR: 1.45, 95%CI: 1.17-1.80) (Fig.1, Panel C); no significant differences in outcomes were observed according to BBs use in AF patients with COPD (Fig. 1, panel D).

Conclusion

COPD is common in AF, being found in 1 every 8 patients, and is associated with an increased burden of comorbidities, differential management and worse outcomes, with more than two-fold higher risk of all-cause death and increased risk of CV death and major bleeding. Therapy with BBs does not increase the risk of adverse outcomes in these patients. Abstract Figure.
Atrial fibrillation and COVID-19 in older patients: a complex, dangerous, association. An analysis of the GeroCovid Registry
Authors: Fumagalli S , Pelagalli G , Trevisan C , Del Signore S , Volpato S , Gareri P , Mossello E , Malara A , Monzani F , Coin A , Bellelli G , Zia G , Antonelli Incalzi R
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

the GeroCovid Investigators

Introduction. Atrial fibrillation (AF) is the most frequent arrhythmia diagnosed in elderly patients. It often associates with disabling complications, such as stroke and systemic embolism. COVID-19 severely affects older subjects, who show a particularly high mortality, often related to relevant alterations in coagulation and inflammation cascade. 

Purpose. Aim of this study was to evaluate how the presence of a prevalent form of AF (at admission or in clinical history) influenced the clinical course of COVID-19 in an aged in-hospital population.

Methods. We studied the acute patients included in GeroCovid, a multicenter retrospective-prospective registry designed by the Italian Society of Gerontology and Geriatric Medicine and the Norwegian Geriatrics Society. GeroCovid, independently of the healthcare setting and without exclusion criteria, enrolled subjects aged >60 years to analyze risk factors, signs, symptoms and outcomes of COVID-19 in older people. For the purpose of this study, only the acute, in-hospital, cohort was evaluated.

Results. Between March 1st and June 6th 2020, 2474 patients were enrolled in GeroCovid. Of these, 806 (32.6%) were assisted in hospital, for an acute condition (age: 79 ± 9 years; men: 51.7%). The prevalence of AF was 21.8%. Patients with the arrhythmia were older (82 ± 8 vs. 77 ± 9 years; p < 0.001) and with a higher CHA2DS2-VASc score (4.1 ± 1.5 vs. 3.2 ± 1.5; p < 0.001). The prevalence of almost all comorbidities was higher in AF patients (in particular, hypertension, cardiac diseases, diabetes, heart failure, peripheral artery disease, chronic renal failure, COPD, stroke, obesity). At multivariable analysis, advanced age (p = 0.010), an increased number of white blood cells (p = 0.031), the presence of cardiac diseases (p < 0.001), peripheral artery disease (p = 0.030) and of signs or symptoms of heart failure (p = 0.003) characterized older patients with AF. In-hospital mortality was significantly higher in patients with the arrhythmia (36.9 vs. 27.5%; OR = 1.55, 95%CI = 1.09-2.20; p = 0.015). A multivariable logistic regression model showed that AF was an independent predictor of mortality (p = 0.021), such as male gender (p = 0.014) and the presence of peripheral artery disease (p = 0.003). COPD, stroke, chronic renal failure, diabetes and obesity were deleted from the final model.

Conclusions. AF is frequently observed in older patients with COVID-19. Subjects with both conditions have a more complex clinical status and show a higher in-hospital mortality, thus requesting a particularly careful and intensive management.
Cardiac autonomic function and cognitive performance in patients with atrial fibrillation
Authors: Haemmerle P , Aeschbacher S , Springer A , Eken C , Coslovsky M , Dutilh G , Moschovitis G , Rodondi N , Chocano P , Conen D , Osswald S , Kuehne M , Zuern CS
Published: May 2021

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Swiss National Science Foundation

OnBehalf

Swiss-AF Investigators

Background

Atrial fibrillation (AF) is associated with loss of cognition and dementia. Cardiac autonomic dysfunction has been linked to cognitive decline. We aimed to investigate if reduced cardiac autonomic function (CAF) is associated with cognitive impairment in AF patients. 

Methods

Patients with paroxysmal, persistent and permanent AF were enrolled from a multicenter cohort study if they presented in AF ("AF group") or in sinus rhythm ("SR group") on a baseline 5-minute ECG recording. Parameters quantifying CAF (heart rate variability triangular index (HRVI), mean heart rate (MHR), the root mean square of successive differences (RMSSD) and the standard deviation of the normal-to-normal intervals (SDNN)) were calculated. We used the Montreal Cognitive Assessment (MoCA) to assess global cognitive function.

Results

1,685 AF patients with a mean age of 73 ± 8 years, 29% females, were included. The MoCA score was 24.5 ± 3.2 in the AF group (n = 710 patients) and 25.4 ± 3.2 in the SR group (n = 975 patients). After adjusting for multiple confounders, lower HRVI was associated with lower MoCA scores, both in the SR group (β=0.049; 95% confidence interval (CI): 0.016 to 0.081; p = 0.003) and in the AF group (β=0.068; 95% CI: 0.020 to 0.116; p = 0.006). In the AF group, higher MHR was associated with a poorer performance in the MoCA (β=-0.008; 95% CI: -0.014 to -0.002; p = 0.014 ). Other parameters of CAF were not associated with cognition.

Conclusion

Our data suggest that impaired CAF is associated with worse cognitive performance in patients with AF. Elderly AF patients with impaired HRVI might undergo cognitive testing in order to screen for cognitive impairment.
Endocardial left atrial appendage occlusion in atrial fibrillation: computational fluid dynamics simulations to assess stroke risk
Authors: Masci A , D"alessandro N , Scivoletto A , Severi S , Ansaloni F , Dal Monte A , Tomasi C , Fabbri C , Corsi C
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background

Percutaneous endocardial left atrial appendage (LAA) occlusion (LAAO) in non-valvular atrial fibrillation (AF) seems comparable to anticoagulation therapy (OAC) as regards thromboembolic risk reduction with a possible additional decrease in major bleeding. LAAO is currently limited to patients with contraindications to OAC, due to its high costs and procedural risks, but better pre-procedural planning and operative techniques might improve the outcome widening practical indications. Computational fluid dynamics (CFD) represents a valuable non-invasive approach to estimate physiologically significant hemodynamic parameters in a complex fluid dynamics system. It might provide a helpful in silico simulation of blood flow patterns within the LA and LAA by using 3D patient-specific models, allowing LAAO planning and effects prediction.

Purpose

This study’s aim was to simulate the fluid dynamics effects of LAAO in AF patients to predict patient-specific hemodynamic changes caused by applying the two most popular devices.

Methods

LAAO was simulated on the 3D LA anatomical models obtained from CT data in 5 AF patients, considering the device specific shape. CFD simulations in AF condition were performed both on the whole LA model and on the models with the LAAO performed with the two devices. Significant fluid dynamics indices (blood velocity, vortex structures, LAA ostium velocity, LA blood stasis) were computed to evaluate the changes in the flow patterns after LAAO in relation to the thrombogenic risk.

Results

Overall we found a more effective washout within the LA after LAAO, in terms of a different spatial distribution of velocities (see figure for a qualitative evaluation of LA blood flow velocity in one patient: (A) model with LA and LAA; models after LAAO applying the Amulet (B) and the Watchman (C) device) and vortex structures (after LAAO, they were decreased in number and increased in size). Moreover, a higher velocity at the mitral valve and at the LAA ostium (peak velocity: 12-17 cm/s in the models with LAA, 40-60 cm/s in LAAO_A and 35-65 in LAAO_W) was detected together with  a slightly improved washout effect in terms of blood stasis with the Watchman device (stasis: 3.1-5.7% in the models with LAA, 1.9-4.1% in LAAO_A, 1.7-3.7% in LAAO_W).

Conclusions

A workflow for simulating the fluid dynamics effects of endocardial LAAO in AF was developed and tested. CFD provides a valuable tool to quantify hemodynamic changes after LAAO and assess thrombogenic risk in patient-specific LA and LAA. Our preliminary results suggest that endocardial LAAO favourably affects blood fluid dynamics in the LA. Abstract figure
Safety and acute clinical outcomes of atrial fibrillation catheter ablation in octogenarians: a multicentre evaluation with a matched younger cohort
Authors: Karim N , Kozhuharov N , Jarman J , Furniss S , Veasey R , Ullah W , Vouliotis A-I , Martin C , Kalla M , Osmanagic A , Ginks M , Pope M , Christian Sitcherling C , Gupta D , Wong T
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Sven Knecht and the International Octogenarian AF ablation group

Background

Octogenarians are a fast-growing demographic with a high burden of atrial fibrillation (AF). There are limited data on procedural safety and acute outcomes of catheter ablation (CA) for AF in this group.

Purpose

Investigation of complications & outcomes in octogenarians undergoing CA for AF.

Methods

Data on all octogenarian patients who underwent AF ablation at nine European cardiology centres between 2013 and 2019 were retrospectively analysed and matched with control patients aged <80 years.  The characteristics used for matching were type of AF, type of procedure (de novo or redo), & the year of procedure.

Results

216 octogenarians (81.9 ± 1.9 years; 52.8% females) underwent an AF ablation procedure, and were matched with 216 patients aged <80 years (62.4 ± 9.5 years, 34.7% females), p <0.001 for both. The proportion of paroxysmal and persistent AF was 43.5% & 56.5% respectively in both groups, and 79.3% of the procedures were de novo. RF ablation made up 75.4% & 75.9% (p = 0.90) procedures in octogenarians and controls respectively.  17 complications occurred in 14 (7.9%) octogenarian patients and 11 in 11 (5.1%) patients in the younger matched cohort (p = 0.07). There were 4.2% & 1.9% major complications (p= 0.17) and 3.7% & 3.2% minor complications (p= 0.77) in the octogenarian & younger cohorts respectively. Complications in octogenarians consisted of groin complications (n = 6), pneumonia (n = 3), pericardial effusion (n = 2), phrenic nerve injury (n = 2), pulmonary oedema (n = 1), gastroparesis (n = 1), stroke (n = 1). Acute procedural success rates were 99.1% & 99.5% (p = 0.62) The complication rates were similar for RF; 6.0% vs 5.4% (p = 0.79) and Cryoballoon; 14.0% vs 4.1% (p = 0.09) in both octogenarians and younger cohort respectively.

Conclusion

In spite of significantly higher overall risk profile of octogenarians undergoing AF ablation, there is no difference in acute procedural success and complication rates as compared to younger patients Catheter ablation of AF in octogenerians Octogenarians n = 216 Matched Controls (aged < 80yrs) n = 216 P value Age (yrs), mean (SD)s 81.9 (1.9) 62.4(9.5) < 0.0001 Females, (%) 52.8 34.7 0.0002 CHA2DS2-VASc, mean (SD) 3.6 (1.2) 1.4 (1.3) < 0.0001 Mean LA size, mm 42.8 ± 8.3mm 45.8 ± 16.2 0.062 Impaired LV function, (%) 23.7 17.9 0.206 IHD, (%) 20.7 5.9 < 0.0001 Procedural time (mins), mean (sd) 150.6 (69.7) 148.9 (64.4) 0.914 All complications, n (%) 17 (7.9) 11 (5.1) 0.073
Anterior position of dispersive patch for esophageal protection during atrial fibrillation ablation. A pilot feasibility study
Authors: Futyma P , Burda N , Surowiec A , Kogut A , Iwanski M , Swierczek P , Futyma M , Kulakowski P
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Introduction

Ablation for atrial fibrillation (AF) carries a significant risk of esophageal injury. Current methods of esophageal protection are invasive, expensive and their cost-effectiveness can be questioned. Standard placement of dispersive patch (DP) at patient’s back exposes esophagus to radio-frequency (RF) current-mediated thermal injury and such complications as esophageal wall ulceration, peri-esophageal injury or life-threatening atrio-esophageal fistula. Redirecting RF current by DP repositioning to anterior chest can theoretically protect oesophagus from thermal injury, however, such an approach has not yet been investigated.

Aim

To determine feasibility of anterior DP position for treatment of AF using RF catheter ablation (RFCA)-based system.

Methods

We retrospectively analysed consecutive patients undergoing  RFCA-based pulmonary vein isolation (PVI) using multi-electrode PVAC catheter with DP located either in anterior or traditional-posterior position. Two additional patients underwent point-by-point RFCA and mapping of PV ostia with impedance measurements during RFCA performed using anterior and posterior DP positioning.

Results

62 patients (25 females, age 60 ± 12 years) underwent PVI using PVAC: 40 patients in posterior and 22 in anterior DP group. There were no major complications during procedures. There was no significant difference in AF recurrence rate between anterior and posterior DP groups during one-year follow up (log rank p = 0.065). In two additional consecutive patients (1 female, age 74 ± 2 years) undergoing point-by-point RFCA a total number of 30 measurements around PV ostia were performed. There was a significant difference between impedance values in anterior vs posterior DP positions (134 ± 7 Ω vs 122 ± 8 Ω, p = 0.0004).

Conclusions

Anterior position of dispersive electrode for PV isolation using RFCA-based systems is safe, feasible, atraumatic and is not associated with any additional cost. Apart from redirecting RF current away from the esophagus, anterior dispersive patch placement is associated with higher impedance values which can act as an additional protection. Possible prevention of esophageal complications using anterior dispersive patch positioning needs to be determined in prospective studies. Abstract Figure. AF-free survival and impedance
A novel local impedance algorithm and contact force sensing to guide high power short duration radiofrequency ablation is efficient and safe for circumferential pulmonary vein isolation
Authors: Schreieck J , Heinzmann D , Scheckenbach C , Gawaz M , Duckheim M
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Introduction

Local impedance (LI) drop can predict sufficient lesion formation during radiofrequency ablation (RF). Recently, a novel ablation catheter technology able to measure LI and contact force has been made available for clinical use. High power short duration (HPSD) RF ablation has been shown to be feasible for atrial fibrillation (AF) ablation with short procedure time. We used LI drop and plateau formation to guide duration of 50 Watt RF power applications for circumferential pulmonary vein isolation (PVI).

Methods

Consecutive patients with indication for de novo AF ablation (n = 32, age 65 ± 10 years) with paroxysmal (n = 16) or persistent (n = 16) AF underwent ultra high density 3D mapping of the left atrium and catheter ablation. Thereafter, ipsilateral PV encircling with 50 Watt RF-applications targeting an interlesion distance of ≤ 6mm and a contact force of 10-30g was performed. Duration of HPSD RF application between 7-15s was guided by impedance drop >20 Ohm and plateau formation of LI. Further ablation strategy was left to the investigator’s discretion. Esophageal temperature measurement was performed using a three thermistor catheter with temperature cut off 39.0°C. In case of temperature rise or very near esophageal contact to the circumferential line, RF application time was shortened to 7s. Patients underwent adenosine testing after PVI. Previously we performed all types of AF ablation using an LI guided HPSD ablation without contact force measurement capability in 80 patients.

Results

Complete PVI was achieved in all pts with only 13.5 ± 4.3 min cumulative RF application duration and an ablation procedure duration of 46.5 ± 10.4 min with the novel LI measuring catheter. First-pass isolation of ipsilateral veins was achieved in 75% of circles. Recurrence of PV conduction during waiting period (20min) and adenosine testing occured in 25% of circles, and was reablated in most patients with a single spot of HPSD application. Using 94 ± 36 RF application per patient, mean maximum LI drop was 23.6 ± 4.0 Ohm. Reconnected fibers were associated with low LI drop due to instability of contact in most cases due to breathing in case of difficult sedation of the patients. No serious complications occurred in all 32 pts using HPSD with the novel contact force catheter design.

Conclusion

Guiding of HPSD RF ablation by LI is highly efficient and safe. A novel local impedance algorithm in combination with contact force sensing enable short PVI times with low early recurrence of PV conduction. Prediction of permanent lesions seems possible and the only limitation seems to be unstable RF catheter contact due patients breathing. Follow up have to be waited.
Pulmonary vein isolation for paroxysmal atrial fibrillation using high-power short duration radiofrequency or second-generation cryoballoon ablation
Authors: Kardos A , Kassa K , Nagy Z , Kis Z , Simkovits D , Som Z , Csakany L , Major T , Foldesi C
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background

Differences in the left atrial (LA) tissue loss can occur following different pulmonary vein isolation (PVI) techniques.

Purpose

Our prospective study compared the biomarker, the LA mechanical, and the electrophysiological findings as indicators of LA myocardial damage after a high-power short duration  (HPSD) with contact force radiofrequency catheter and second-generation cryoballoon (CB2) ablation of paroxysmal atrial fibrillation (AF).

Methods :We enrolled 40 patients with paroxysmal AF [16 (40%) women, mean age = 55.9 ± 12.4 years] who underwent HPSD (n = 21) or CB2 (n = 19). Biomarker levels (hs-cTnT, CK-MB, hs-CRP, LDH) and the transport function of the LA by transthoracic echocardiography (TTE) were compared pre and post procedurally. High-density mapping (HDM) was performed in sinus rhythm using a multielectrode diagnostic catheter in each group to define isolated left atrial low voltage area (LVA; <0.2mV in bipolar voltage mapping).  LA CT-angiography and HDM merge was used to calculate the post-PVI LVA and the LVA/LA surface ratio.

Results

Postablation hs-cTnT and hs-CRP levels were comparable in the ablation groups (HPSD: 1249 ± 469 and 9.53 ± 10.30 vs. CB2: 995 ± 280 and 12.36 ± 5.76, p = 0.065 and p = 0.732), while CK-MB and LDH levels were significantly higher following CB2 ablation (HPSD: 6.61 ± 2.62 and 349.9 ± 65.6 vs. CB2: 26.01 ± 6.88 and 451.6 ± 91.3, p < 0.001 and p < 0.001). The transport function of the LA did not change significantly by TTE after the procedure. Fractional Area Change at baseline and 3 months was 33.9 ± 13.8 and 33.5 ± 10.7  p = 0.9 in the HPSD group while 38.1 ± 8.6 and 35.3 ± 12.2 p = 0.9 in the CB2 group.  LA Ejection Fraction measured in the two groups (before and 3-month post-procedure): HPSD: 51.2 ± 20.5% and 49.5 ± 14.7%, p = 0.9, CB2: 49.7 ± 15.5% and 50.7 ± 13.3%, p = 0.8). Ablation time was comparable in the two groups (HPSD: 1676 ± 570 sec, CB2: 1495 ± 494 sec, p = 0.279), while fluoroscopy time and radiation exposure were significantly higher in the CB2 group (HPSD: 5.62 ± 4.31 min and 232 ± 406 cGycm2, CB2: 13.65 ± 5.18 min and 1819 ± 1669 cGycm2, p <0.001 and p <0.001). The LVA/LA surface ratio were: HPSD group: 8.37 ± 6.42% and CB2 group: 13.58 ± 8.92% (p = 0.007). At 12-month follow-up, the success rate, defined as freedom from AF/atrial tachycardia without antiarrhythmic drug was 80.1% (HPSD) and 84.2% (CB2) respectively.

Conclusions

The LA scar tissue was significantly higher following CB2 ablation, but did not affect medium-term efficacy. However, tissue loss did not reduce the transport function of the LA.
Oesophageal thermal protection during AF ablation: effect on left atrial myocardial ablation lesion formation and patient outcomes
Authors: Leung L , El Batran A , Dhillon G , Bajpai A , Zuberi Z , Li A , Norman M , Kaba RA , Akhtar Z , Evranos B , Al Subaie N , Sohal M , Louis-Auguste J , Hayat J , Gallagher MM
Published: May 2021

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Dr Leung has received research support from Attune Medical (Chicago, IL). Dr Gallagher has received research funding from Attune Medical (Chicago, IL).

Background

Randomized evidence has shown that controlled oesophageal cooling is effective at reducing oesophageal thermal injury during radiofrequency (RF) ablation for atrial fibrillation (AF) compared to standard care. The effect of oesophageal cooling on ablation lesion formation in left atrial myocardium and patient outcomes at 12-months had not been previously studied.

Purpose

To determine the effect of oesophageal cooling on the formation of RF lesions, the ability to achieve procedural endpoints and long-term patient outcomes compared to standard care ablations.

Methods

Ablation results and patient outcomes from a double-blind randomized controlled trial were analysed (IMPACT trial NCT03819946). AF ablation was guided by Ablation Index technology (30W at 350-400 AI posteriorly, 40W at 450 AI anteriorly). A blinded 1:1 randomization assigned patients to the use of an oesophageal temperature control device to keep oesophageal temperature at 4 degrees during ablation or standard practice using a single-sensor temperature probe. Ablation parameters and 12-month outcomes were analysed.

Results

  We recruited 188 patients. Procedure and fluoroscopy times were similar. First pass pulmonary vein isolation and reconnection at the end of the waiting period were similar in both randomized groups (51/64 vs 51/68; p = 0.54 and 5/64 vs 7/68; p = 0.76, respectively). Posterior wall isolation was also similar: 24/33 vs 27/38; p = 0.88. Ablation effect on myocardial tissue, measured in impedance drop, was also similar: 8.6Ω (IQR: 6-11.8) vs 8.76Ω (IQR: 6-12.2; p = 0.25) and median catheter tip temperature was the same at 25.5 degrees. Arrhythmia recurrence was similar at 12 months (20.3% vs 26.8%, from 142 completed assessments; p = 0.66).

Conclusions

  Oesophageal cooling has been shown to be effective in reducing ablation-related oesophageal thermal injury during RF ablation. Ablation data show that this protection does not make it any more difficult to achieve standard procedural endpoints or clinical success at 12-months. Abstract Figure. Pyramid frequency plots of AI values
Incidence of new-onset atrial fibrillation after cavotricuspid isthmus ablation for isolated typical atrial flutter: a systematic review and meta-analysis
Authors: Griffin A , Thiyagarajah A , Middeldorp M , Lau D , Sanders P
Published: May 2021

Funding Acknowledgements

Type of funding sources: None.

Background

There is a lack of consensus guidelines regarding the continuation of anticoagulant therapy following cavotricuspid isthmus (CTI) ablation for typical atrial flutter.  This is despite a significant number of patients developing new-onset atrial fibrillation (AF) following the procedure.  Furthermore, a summary of Kaplan-Meier estimates for drug-free, arrhythmia-free survival has never been reported.

Purpose

 To estimate the incidence of drug-free, new-onset AF stratified by rhythm monitoring strategy in patients undergoing  CTI ablation for isolated typical atrial flutter.

Methods

PubMed, Embase and MEDLINE databases were searched to identify relevant studies. Only studies where anti-arrhythmic drugs were discontinued post-ablation and that accounted for patient censoring by reporting results in the form of time to event data were included.  Data was extracted from published Kaplan-Meier curves using a digitizing software and confidence intervals for the survivor function were estimated based on the number at risk at the time point of interest. Results were pooled in a random effects model using the DerSimonian-Laird estimator.

Results

 Thirteen relevant studies incorporating 1712 patients (79 % male, mean age 63.2 +/-11.2 years,  LVEF 55.2 +/-10.8%) were identified. The estimated  freedom from  new-onset atrial fibrillation was 89.7% (95% CI: 80.3-90.1%) at 1 year and 86.2% (95% CI: 78.4-94.0%) at 2 years in patients undergoing predominantly symptom –based monitoring, 74.6% (95%CI: 67.0-82.3%) at 1 year and 69.5% (95%CI: 63.5-75.6%) at 2 years  in patients undergoing regular clinic follow-up with periodic Holter monitoring and 51.4% (95% CI: 41.8-61.0%) at 1 year and 22.7% (95% CI: 8.7% - 36.6%) at 2 years in patients with implantable loop recorders.

Conclusion

 With the advent of implantable loop recorders, it is apparent that most patients with isolated atrial flutter manifest new-onset AF following CTI ablation and the merits of discontinuing anticoagulation must be carefully considered in this population.  Symptom-based monitoring likely severely underestimates the incidence of new-onset AF and may lead to adverse outcomes, particularly in patients with a high risk of stroke.