Predictive value of late gadolinium enhancement MRI in patients with persistent atrial fibrillation. Multicentric validation of a standardised method

Background

With recurrence rates after PVI in persistent atrial fibrillation (AF) as high as 50%, predictive tools to improve patient selection are clearly needed. Compared to paroxysmal AF, persistent AF is more substrate-dependent. While endocardial low voltage substrate detected by invasive mapping has been shown to predict AF recurrence, to date the only non-invasive method to assess arrhythmogenic substrate is late gadolinium enhancement (LGE)-MRI. In fact, patient selection for PVI based on left atrial (LA) LGE extent according to the UTAH stages has been proposed, However, this approach has not been widely established, in part owed to the lack of standardisation and thus limited reproducibility of the MRI postprocessing method. Moreover, in the recent DECAAF-2 multicenter trial, the UTAH stages failed to predict outcome in patients with persistent AF.

Purpose

We have recently established a standardised MRI method that aims at reproducible quantification of LGE. Here, the ability of this method to detect arrhythmogenic substrate and to predict outcome after PVI in patients with persistent AF was evaluated by two centers independently.

Methods

This dual center study consisted of a prospective derivation cohort at centre1 and a validation cohort at centre 2. All patients received an LGE-MRI prior to ablation (PVI only) and were followed systematically with holter ECG at 3, 6 and 12 months. Gradient echo MR sequences were acquired in sinus rhythm and LA 3D-reconstruction performed using ADAS-3D software.

LGE was quantified based on the signal intensity ratio of each voxel relative to the blood pool, applying a uniform threshold of >1.2 to define LGE indicative of fibrotic tissue. Invasive mapping served as a reference defining arrhythmogenic substrate (>2 cm2 LA area with bipolar voltage <0.5 mV).

Results

A ROC analysis of 37 consecutive patients with persistent AF in the prospective derivation cohort yielded a cutoff-value of 12% LGE to predict relevant low-voltage substrate with the highest accuracy. This cutoff-value was also predictive of AF recurrence after PVI (Fig. 1). When applied to the external validation cohort of 182 consecutive patients, the cutoff-value of 12% was also predictive of AF recurrence after PVI – both in the full cohort (odds ratio 3.3, p=0.003) and in the subgroup of 65 patients with persistent AF (odds ratio 3.7, p=0.038). Of note, among patients with persistent AF, recurrence rate was 54% in those with >12% LGE but only 24% in those with <12% (Fig. 2).

Conclusion

This dual center study established and validated the predicitive value of LGE as determined by a standardised MRI method in patients with persistent AF that can be reproducibly applied across different centers. A cutoff-value of 12% LGE was able to discriminate between responders and non-responders to PVI and may thus guide selection of suitable candidates that are likely to benefit from ablation.

Funding Acknowledgement

Type of funding sources: None.

Impact of procedural volume on complication and recurrence rate after atrial fibrillation ablation in European centers. An ESC EORP Registry: Atrial Fibrillation Long-Term

Background

Catheter ablation has emerged as an effective therapy in patients with atrial fibrillation (AF). Despite high success rates of the method, there is still heterogeneity of outcomes and complications across Europe. A center's volume of AF ablations performed per year might also play an important role in the success rate of the procedure as compared to other confounding factors which may be different among centers (such as type of AF ablated, patient selection criteria, referral bias and/or ablation strategy).

Purpose

Aim of the study was to investigate differences in clinical outcomes and complication rates among European AF ablation centers related to the volume of ablations performed annually.

Methods

Data for this analysis were extracted from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 33th and 67th percentiles of number of AF ablations performed, the participating centers were classified into high volume (HV) (≥180 procedures/year), medium volume (MV) (<180 and ≥74/year) and low volume (LV) (<74/year). One-year success was defined as patient survival free from any atrial arrhythmia, from the end of the 3-month blanking period to 12 months following the ablation procedure.

Results

A total of 91 centers in 26 European countries enrolled 3368 patients. There was a significantly higher reporting of cardiovascular complications in LV centers (5.2%), especially pericarditis and cardiac perforation, while the HV and MV centers reported cardiovascular complications in 3.0 and 4.3% of cases, respectively (p=0.039). Additionally, stroke incidence after ablation was significantly higher in LV centers (0.5% of cases vs 0% in HV and MV centers, p=0.008). One-year success after AF ablation ranged from 77.8% in HV vs 70.5% in LV vs 77.3% in MV centers (p<0.001). Despite these unadjusted differences, Kaplan-Meier survival analysis based on adjusted data demonstrated, however, that there were not significant differences in complication and recurrence rates according to volume's center (p=0.328 and p=0.476 accordingly, Figure A). This result was mainly driven by a proportional increase in severity/risk of cases ablated (as evidenced by CHA2DS2-VASc score and AF type) in relation to a center's procedural volume (Figure B).

Conclusions

Low volume centers present slightly higher cardiovascular complications' and stroke incidence and a lower unadjusted success rate after AF ablation. On the other hand, adjusted overall complication and recurrence rates are non-significantly different among different volume centers, a fact reflecting inhomogeneity of patient and procedural profiles and a counterbalance between expertise and risk level among participating centers.

Funding Acknowledgement

Type of funding source: None

Electromechanical delay by speckle-tracking echocardiography: a novel tool for distinguishing between Brugada syndrome and isolated right bundle branch block

Background

The electrocardiographic (ECG) definition of Brugada syndrome (BS) can be challenging because benign ECG abnormalities, such as right bundle branch block (RBBB), may mimic pathological ECG characteristics of BrS. However, although myocardial delay and deformation can be quantified by advanced imaging, it has not yet been used to differentiate between BrS and RBBB.

Purpose

The aim of this study was to characterize the electro-mechanical behavior of the heart of patients with type-1 BrS and subjects with isolated complete RBBB in order to differentiate these conditions.

Methods

In this two-center study, 66 subjects were analyzed by standard and speckle-tracking echocardiography (STE): 22 type-1 BrS, 24 isolated complete RBBB, and 20 healthy subjects. The participants were not treated by any drug potentially influencing myocardial conduction.

Results

Standard echocardiographic parameters did not differ among the groups. STE demonstrated that right ventricular (RV) mechanical dispersion (MD) was greater in RBBB as compared to BrS and controls (p<0.05). In patients with isolated RBBB, the greatest delay of RV time-to-peak longitudinal strain (TTP) was found in RV free-wall basal segments. Mean absolute deviations of TTP calculated for each left ventricular (LV) region were greater in patients with RBBB as compared to those with BrS and to controls with a localisation of the delay in LV antero-septal, anterior, lateral, and infero-septal basal segments (figure 1).

Conclusions

Advanced echocardiographic techniques may help to differentiate between BrS and RBBB. Indeed, STE allows to identify an electro-mechanical conduction delay in RBBB patients that is not found in patients affected by type-1 BrS.

Electromechanical delay by STE

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Italian Society of Cardiology

P1016Correlation between cardiac magnetic resonance-late gadolinium enhancement and electro-anatomical map for right atrium

Funding Acknowledgements

none

Background

 Electroanatomical map (EAM) detects areas of low voltage as a surrogated marker of fibrosis areas, being the reference technique for its detection. Cardiac magnetic resonance with Late Gadolinium enhancement (CMR-LGE) allows non-invasive detection of atrial fibrotic areas. CMR-LGE studies have focused on the left atrium since now.

Purpose

We need to validate this test to extend its use to the right atrium (RA), since it is involved in the arrhythmogenic substrate of several arrhythmias, and probably also in atrial fibrillation (AF).

Methods

 Prospective observational study. Fifteen patients undergoing a first AF ablation procedure were included. All patients had a pre-procedural LGE-CMR performed. The blood pool-normalized intensity signal (image intensity ratio-IIR) was calculated for the right atrial wall, and values projected in a shell. IIR values validated for the left atrium were used to identify dense and intermediate fibrosis, and healthy tissue (>1.32, 1.2-1.32, <1.2, respectively). During the procedure but before ablation, a point-by-point high density EA bipolar voltage map of RA was obtained with a multipolar catheter. Standard voltage thresholds of 0,1 mV and 0,5 mV were used to characterize fibrotic and healthy tissue in EAM. For each RA, the EAM was projected into the IIR shell, and the correlation between bipolar voltage and normalized IIR values for each shell point was quantified. Then, we also obtained its concordance (categorical variables) according to the label automatically assigned by EAM/CMR with the pre-set thresholds: healthy tissue/ intermediate fibrosis/dense fibrosis.

Results

 A total of 8,830 points were obtained, mean per patient 588 (± 509) points. A global weak negative correlation was found between the EA bipolar voltage map (EAM) and IIR (CMR) (r= -0.16, p < 0.0001)(figure). LGE-CMR identified more healthy tissue than EAM (81.0% vs 60.6% respectively), then CMR underestimated the fibrotic tissue in RA. Finally, we analyzed the concordance and we obtained that the degree of accuracy between both measurements was 55.7%.

Conclusion

 There was an inverse correlation between the bipolar voltage EAM and IIR (CMR) of low grade but with statistical significance. CMR underestimated fibrotic tissue in RA with respect to its identification by EAM.

Abstract Figure. Correlation between bipolar voltage-IIR

129Magnetic resonance predictors of ventricular tachycardia recurrence after radiofrequency substrate ablation: septal and transmural channels

 

Ventricular tachycardia (VT) substrate-based ablation has become a gold standard in patients with structural heart disease. Success of VT ablation is related with mortality reduction.

Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) is a powerful technique to assess substrate of VT. Myocardial fibrosis is electrically inert (Core) but it is surrounded by a ‘‘border-zone (BZ)’’ where normal cardiomyocytes intermingle with dense bundles of fibrosis. Slow impulse conduction in the BZ allows for the re-entry circuits leading to VT. Both the presence and extent of LGE have been associated with VT and SCD risk. LGE-CMR tissue characterization can be depicted as pixel signal intensity (PSI) maps and can guide VT ablation.

The aim of this study was to analyze possible VT recurrence predictors in a long term follow-up of patients that underwent VT ablation (endo and/or epicardial) related with LGE-CMR PSI maps.

We analyzed 234 consecutive patients (age: 63.2 ± 14 years, follow-up: 3.14 years ±1.8) undergoing VT ablation with scar-dechannelling technique at a single center from 2013 to 2018.  110 patients underwent a preprocedural LGE-CMR, and in 94 patients (85,5%) a CMR-aided ablation using the PSI maps was performed.

All LGE-CMR images were semi-automatically processed using a dedicated software. PSI-based algorithm was applied to characterize the hyperenhanced area as core or BZ, using fixed threshold of the maximum intensity. A LV 3D shell was obtained and were imported into the navigation system. In the PSI maps, heterogenous tissue channels were defined as a continuous corridor of BZ surrounded by scar core or an anatomic barrier that connects 2 areas of healthy tissue.

Results

Overall recurrence of VT was 41.8 %. There was ICD shock reduction, from 43,6% to a 28,2% (ICD shocks before ablation 2,23 ± 7,32, after: 1,10 ± 2,92).

Left ventricle mass predicted significantly VT recurrence (Mean 168,3 ± 53,3 vs 152,3 ± 46,4 g, HR 1,02 [1,01-1,02], p < 0.001). LGE distribuition was predictive of VT recurrence when a more than 40% of the interventricular septum was involved (62,5% vs 37,8%; HR 1,6 [1,01-1,02]; p = 0,044). No differences in recurrence were found among the patterns of LGE distribution (transmural/epicardial/subendocardial or peculiar segments localizations). The amount of BZ and the total amont of Core + BZ was related with VT recurrence (BZ 26,6 ± 13,9 vs 19,56 ± 9,69 g, HR 1,03 [1,01-1,06], p = 0,012; total Core + BZ 37,1 ± 18,2 vs 29,0 ± 16,3 g, HR 1,02 [1,00-1,04], p = 0,033). Finally VT recurrence was higher in patients with channels with transmural path (66,7% vs 31,4%, HR 3,25 [1,70-6,23], p < 0,001) or midmural channels (54,3% vs 27,6%, HR 2,49 [1,21–5,13], p = 0,013).

CMR-aided scar dechanneling is a helpful and feasible technique which could identify patients with high risk of VT recurrence. High left ventricular mass, septal LGE distribution, transmural and midmural heterogeneous tissue channels were predictive factors of post ablation VT recurrence.

Abstract Figure. VTchannel & heterogeoneus tissue channel

45Improving the optimization of cardiac resynchronization therapy: Does multipoint left ventricular pacing shorten the paced-QRS duration compared to the fusion-optimized intervals method?

Funding Acknowledgements

Cardiac Pacing Scholarship from the Spanish Society of Cardiology (SEC)

Background

Electrocardiogram-based optimization of cardiac resynchronization therapy (CRT) using the fusion-optimized intervals (FOI) method has demonstrated to improve both acute hemodynamic response and left ventricle (LV) reverse remodeling compared to nominal programming of CRT. FOI optimizes the atrioventricular (AV) and ventriculo-ventricular (VV) intervals to achieve the shortest paced-QRS duration. The recent development of multipoint pacing (MPP) enables the activation of the LV from 2 locations, also shortening the QRS duration compared to conventional biventricular pacing.

Purpose

To determine if MPP reduces the paced-QRS duration compared to FOI optimization. 

Methods

This prospective clinical study included 25 consecutive patients who successfully received a CRT with MPP pacing capability. All patients were in sinus rhythm and had an PR interval below 250 ms. The QRS duration was measured with a 12-lead digital electrocardiography (screen speed of 200 mm/s) at baseline and using 3 different configurations: MPP, FOI and a combined FOI-MPP strategy. In MPP, the intervals were (based on previous studies): 1) AV 130 ms, 2) Right ventricular (RV)-LV2 (Δ1) 5 ms, and 3) LV1-LV2 (Δ2) 5 ms. In FOI, AV and VV intervals were optimized to achieve fusion between intrinsic conduction and biventricular pacing. In FOI-MPP, the Δ2 was set at 5 ms, while AV and Δ1 intervals were optimized using the FOI method. The CRT device was programmed with the configuration that achieved a greater paced-QRS shortening. After 45 days, battery life was estimated.

Results

  Mean age was 65 ± 10 years, 20 were men (80%) and baseline QRS duration was 177 ± 17 ms. The FOI method bested nominal MPP (QRS shortened by 58 ± 16 ms vs 43 ± 16 ms, respectively, p = 0.002). Adding MPP to the narrowest QRS by FOI did not result in further shortening (FOI: 58 ± 16 ms vs FOI-MPP: 59 ± 13 ms, p = 0.81). The final configuration was FOI method alone in most cases (n = 16, 64%) and FOI-MPP in all others (n = 9, 36%; figure). In total, 10 out of 25 patients (40%) were not candidates to MPP due to: 1) pacing thresholds exceeding 3.5 V/0.4 ms at the distal or proximal electrode (8, 32%), and 2) phrenic stimulation (2, 8%). Estimated battery longevity was longer in patients receiving FOI as compared to MPP (8.3 ± 2.1 years vs. 6.2 ± 2.2 years, p = 0.04).

Conclusion

In CRT, the FOI method is not improved by coupling with MPP.  Up to 40% of patients are not candidates for MPP due to high thresholds or phrenic stimulation. The use of MPP in unselected patients would result in a decrease of battery longevity, without any additional benefit over FOI.

Abstract Figure.

P1129Bipolar voltage cut-off validation in electroanatomical voltage mapping to identify scar and conduction channels in ventricular tachycardia ablation: need for new cut-off in NICM

Background/Introduction

Substrate-guided techniques have changed the approach and results of ventricular tachycardia (VT) ablation and electroanatomical voltage mapping (EAVM) constitutes a diagnostic and therapeutic cornerstone in this field. In current practice normal myocardium is typically characterized by bipolar voltage > 1.5 mV, dense scar < 0.5 mV, and border zone (BZ) tissue by the range between 0.5 to 1.5 mV. Of note, evidence for these cut-off values has been derived in humans from small observational studies and in animals. Furthermore, some studies suggest that only the 60% of not transmural endocardial scars and the 35% of not endocardial scars are detected without any adjustment of these values. New voltage cut-off values are needed.

Purpose

The purpose of this study is to adjust voltage cut off in order to establish the threshold that more accurately define the pathological substrate in VT ablation. Additionally, predictors of usefulness of current thresholds are analyzed.

Methods

EAVM were created with CARTO3 System and Sensor-Force catheter (Navistar Smart-Touch and Pentaray). We delineated the conducting channels by analyzing the late potentials activation. Based on these channels we looked for the best cut-off values to detect these channels. We describe the baseline characteristics, the best cut-off values for border zone and scar core in our series and we analyzed the accuracy of the current established values to detect the arrhythmogenic VT substrate

Results

We investigated 51 patients (74,5% males; 41,2% ischemic cardiomyopathy, mean LVEF 38,6% +/-13,6) with sustained monomorphic VT submitted to ablation during 2016 and 2017. The range of the voltage adjustment was from 0,01-1 mV for core area and 0,2-6mV as maximum, with an average of 0,31-1,42mV. Using currently accepted bipolar voltage cut-off <0.5 mV the core scar was correctly identified in 80,4% of patients: 90,4% in ischemic and 73,3% in NICM. Regarding BZ, using classical cut off (0.5-1.5mV) only 56,9 % of the cases were well identified: interestingly, accuracy was worse in NICM (46,6%) than in ischemic patients (71,4%) (p = 0,07).

Conclusions EAVM is very important to detect scar and channels in VT ablation, but several elements can affect it and recently the traditional voltage values have been questioned. Our study suggests how the threshold as currently applied in daily practice could be acceptable to detect the core scar area, but it has to be reconsidered in NICM, especially regarding the border zone. An evident trend (p = 0,07) suggests a better accuracy of current values to define VT substrate in ischemic patients than in NICM.

Abstract Figure. Channel Identification

P402Analysis of right atrium remodeling by cardiac magnetic resonance in patients with atrial fibrillation and its association with left atrium

Funding Acknowledgements

none

Background

Atrial fibrillation (AF) causes changes in atrial anatomy and this remodeling leads to the arrhythmogenic substrate. Most studies with cardiac magnetic resonance-late gadolinium enhancement (CMR-LGE) have focused on the left atrium (LA); The role of the right atrium (RA) in AF is unknown.

Purpose

To evaluate RA remodeling parameters and its comparison with LA in patients with AF.

Methods

Observational study. We included 109 patients: 9 healthy volunteers, 55 paroxysmal AF, 45 persistent AF. All of them had a CMR-RTG 3.0 T. Image post-processed with segmentation of both atria. Comparison of mean parameters of RA and LA (T test), correlation between them (R Pearson). Multivariate analysis (Cox regression) to study predictive factors.

Results

AF patients had a mean age of 58.5 ± 10.5 years, 70(70%) were men, without structural heart disease 80(80%), and associated atrial flutter 11(11%). The RA parameters were compared by subgroups. We found differences in (healthy/paroxAF/persistAF): area(cm2) 94.0 ± 15.9 /125.3 ± 20.8/ 152.8 ± 24.4 (p <0.0001); volume (ml) 76.7 ± 19.6/ 107.0 ± 25.6/ 150.9 ± 37.6 (p <0.0001); and total fibrosis (%) 3.7 ± 4.3/ 16.5 ± 14.1/ 19.4 ± 15.9 (p 0.014).

RA was higher than LA in all subgroups. There was more fibrosis in RA in paroxysmal/persistent AF. Both types of AF had at least a moderate correlation for area, volume and fibrosis (table).

Finally, RA sphericity was the only predictor factor of AF recurrence after ablation among RA remodeling parameters (HR 1.1 95%CI [1.0 -1.3], p = 0.049).

Conclusions

Area, volume and fibrosis progressively increased from healthy to paroxysmal AF, and then to persistent AF. RA was higher than LA and it also had more fibrosis in patients with AF. The size and fibrosis between both atria had at least moderate correlation. The RA sphericity was a predictor of post-ablation AF recurrences.

COMPARISON/CORRELATION RA LA p R PEARSON(RA/LA) p HEALTHY VOLUNTEERS Volume (ml) 76.7 ± 19.6 37.0 ± 9.4 <0.0001 0.457 0.254 Total Fibrosis (%) 3.7 ± 4.3 5.0 ± 6.1 0.278 0.837 0.005 PAROXYSMAL AF Volume (ml) 107.0 ± 25.6 69.5 ± 26.5 <0.0001 0.422 0.001 Total Fibrosis (%) 16.5 ± 14.1 8.0 ± 8.6 <0.0001 0.485 <0.0001 PERSISTENT AF Volume (ml) 150.9 ± 37.6 103.2 ± 28.5 <0.0001 0.582 <0.0001 Total Fibrosis (%) 19.4 ± 15.9 10.5 ± 11.7 <0.0001 0.571 <0.0001

Abstract Figure. Correlation of area and fibrosis RA/LA

P4762What do atrial fibrillation ablation procedural volume differences across European centers reflect? An ESC EORP registry: atrial fibrillation long-term

Background

Data from the European Atrial Fibrillation (AF) Ablation Long-Term Registry suggest that there are significant differences in the volume of AF ablation procedures performed across different centers even in the same country. If these differences in AF ablation volume between centers reflect regional, socioeconomic, infrastructural/technical or other disparities has not been addressed till now.

Purpose

The aim of this study was to investigate patient and non-patient related differences among European AF ablation centers according to the volume of AF ablations performed.

Methods

Data for this analysis originate from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 25th and 75th percentiles of AF ablation numbers performed, the participating centers were classified into high volume (HV) (≥250 procedures/year), medium volume (MV) (<250 and ≥58/year) and low volume (LV) (<58/year). Patient (demographics, comorbidities) and non-patient (center infrastructure, procedural characteristics) related differences were assessed.

Results

A total of 91 centers in 26 European countries enrolled 3368 patients. There were no significant differences concerning regional distribution, hospital/cardiology facilities or services provided among centers with the exception of electrophysiology procedures and labs which were more abundant in HV centers (p=0.02 and <0.001 respectively). HV and MV centers ablate twice more cases of long-standing persistent and persistent AF compared to LV centers, in which paroxysmal AF reaches 78.9% of all cases (Figure A). Accordingly, first AF ablation procedure was far more frequent in LV centers compared to MV and HV (85.8% vs 76.0% vs 76.1% respectively, p<0.001). Even though HV centers ablate significantly more high risk patients (CHA2DS2-VASc score ≥2 51.4% in HV vs 46.5% in MV vs 37.2% in LV, p<0.001) (Figure B) with accompanying comorbidities, applying more elaborate ablation techniques, fluoroscopy time and radiation dose were higher among patients undergoing AF ablation in LV centers (p<0.001 for all). Despite the above-mentioned dissimilarities, Kaplan-Meier survival analysis, based on adjusted data, demonstrated non-significant differences in complication rate (p=0.402) or AF recurrence rate (p=0.363) among HV, MV and LV centers.

Conclusions

Volume of AF ablations in a center is not correlated with regional or infrastructural characteristics. The higher volume in HV centers consists mainly by more long-term persistent AF and higher risk patients, suggesting that differences in volume reflect differences in experience and personnel's commitment towards AF ablation.

P1028Impact of atrial fibrillation ablation procedural volume on complication and recurrence rate across European centers. An ESC EORP registry: atrial fibrillation long-term

Background

Catheter ablation has emerged as an effective therapy in patients with symptomatic and drug refractory atrial fibrillation (AF). Despite high success rates of the method, there is still heterogeneity of outcomes and complication rate across Europe. The impact of the annual procedural volume per center on success and complication rate of AF ablation, based on real-life data, has not been addressed till now.

Purpose

The aim of the study was to investigate if center AF ablation volume might be associated with one-year success or complication rate after the procedure.

Methods

Data for this analysis were extracted from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 25th and 75th percentiles of AF ablation numbers performed, the participating centers were classified into high volume (HV) (≥250 procedures/year), medium volume (MV) (<250 and ≥58/year) and low volume (LV) (<58/year). One-year success was defined as patient survival free from any atrial arrhythmia, from the end of the 3-month blanking period to 12 months following the ablation procedure.

Results

A total of 91 centers in 26 European countries enrolled 3368 patients. There was a significantly higher reporting of cardiovascular complications in LV centers (5.2%), especially pericarditis (0.6%) and cardiac perforation (1.4%), while the HV and MV centers reported cardiovascular complications in 3.0 and 4.3% of cases, respectively (p=0.039). Additionally, stroke incidence after ablation was significantly higher in LV centers (0.5% of cases vs 0% in HV and MV centers, p=0.008). Kaplan-Meier survival analysis based on adjusted data of all complications demonstrated, however, that there was not a significant difference in complication rate according to volume's center (p=0.402, Figure A). One-year success after AF ablation ranged from 77.8% in HV vs 70.5% in LV vs 77.3% in MV centers (p<0.001). Nonetheless, adjusted recurrence rate was not significantly different among centers (p=0.363, Figure B), a result driven by differences both in ablation technical characteristics and risk/severity of cases ablated in different volume centers.

Conclusions

Despite the notion that “the higher, the better”, our results suggest that AF ablation is a safe procedure with high success rates in all European centers, independent of the AF ablation procedural volume. Differences in patients and procedural characteristics may justify the equality of complication and recurrence rate among centers, since expertise level counterbalances the risk of each case.

P341Which patients with atrial fibrillation undergo an ablation procedure today in Europe? A report from the ESC-EHRA-EURObservational Research Programme

Aims

Great heterogeneity in rhythm control management of patients with atrial fibrillation (AF) has been described. The aim of this study was to investigate how selective the patient cohort referred for AF ablation is, as compared to the general AF population in Europe, and to describe the governing mechanisms for such selection.

Methods

Descriptive comparative statistical analyses of the baseline characteristics were performed between the cohorts of Atrial Fibrillation Ablation Long-Term (ESC-EORP EHRA AFA-LT) Registry, designed to provide a picture of contemporary real-world AF ablation, and the AF population from the AF-General (ESC-EORP EHRA AF-Gen) PilotRegistry. Data collection was performed using a web-based system.

Results

In the AFA and in the AFG pilot registries 3593 and 3049 patients were enrolled, respectively. Patients who underwent AF ablation were younger,more commonly male, and had significantly less co-morbidities. Lone AF was predominant in AFA patients who were at lower risk of stroke (CHA2DS2-VASc >5: 2.9% vs. 24.5%, all P<0.001) and bleeding (HAS-BLED ≥2: 8.5% vs. 40.5%, P<0.001) but with EHRA scores >1 and more prevalentAF-related symptoms such as palpitations, fatigue and weakness (all p<0.001)as compared to the general AF patients. AFA patients were significantly more often male, had higher LV ejection fraction (59.5% vs. 52.4%) and smaller left atrial size on echocardiogram (P<0.001 each).

Conclusions

The comparison of the patient chorts in the AFA and AFG registries showed that AF ablation in European clinical practice is mostly performed in relatively young, symptomatic and otherwise relatively healthy patients.

Acknowledgement/Funding

Abbott Vascular Int.; Amgen Cardiovascular, AstraZeneca, Bayer, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb and Pfizer Alliance

INFLUENCE OF CATHETER ABLATION OF PAROXYSMAL SUPRAVENTRICULAR TACHYCARDIA ON PATIENTS' ANXIETY

The aim of the study was to investigate the influence of catheter ablation of paroxysmal supraventricular tachycardia on patients' anxiety levels. We investigated 70 consecutive patients with paroxysmal supraventricular tachycardia (AV Nodal Reentrant Tachycardia (AVNRT), AV Reentrant Tachycardia (AVRT) or Atrial Tachycardia (AT)) who underwent a catheter ablation. The patients filled out the State and Trait Anxiety Inventory (STAI) before the ablation on the day of the procedure and after 3 months of a successful catheter ablation. State and trait anxiety scores were compared before and after 3 months of ablation. The results were analyzed between different age (<50 vs ≥50 y), gender and the type of paroxysmal supraventricular tachycardia (AVNRT vs AVRT/AT). Both state and trait anxiety scores improved significantly after catheter ablation. State anxiety score improved from mean 42.21±9.53 to 31.43±8.02 (p<0.001). Trait anxiety score improved from mean 45.76±7.80 to 39.80±7.33 (p<0.001). Present study demonstrates that the radiofrequency catheter ablation of paroxysmal supraventricular tachycardia by providing cure and eliminating the arrhythmia episodes significantly reduces both situational and general anxiety levels.

IMPACT OF RADIOFREQUENCY CATHETER ABLATION ON HEALTH-RELATED QUALITY OF LIFE ASSESSED BY THE SF-36 QUESTIONNAIRE IN PATIENTS WITH PAROXYSMAL SUPRAVENTRICULAR TACHYCARDIA

The aim of the study was to investigate the effect of catheter ablation on different aspects of health-related quality of life in association with patients' age, gender and the type of paroxysmal supraventricular tachycardia. We investigated 70 consecutive patients with paroxysmal supraventricular tachycardia (AV Nodal Reentrant Tachycardia (AVNRT), AV Reentrant Tachycardia (AVRT) or Atrial Tachycardia (AT)) who underwent a catheter ablation. The patients were asked to fill out the short form (SF-36) health questionnaire before the ablation on the day of the procedure and after 3 months of a successful catheter ablation and eight health concept scores (1. Physical functioning; 2. Role limitations due to physical health; 3. Role limitations due to emotional problems; 4. Energy/fatigue; 5. Emotional wellbeing; 6. Social functioning; 7. Bodily pain; and 8. General health) were assessed before and after ablation. All health concept scores improved significantly after successful catheter ablation procedure. The result for the whole group were as follows: 1. physical functioning improved from mean 61.42±24.82 to 77.15±18.80 (p<0.001). 2. Score for the role limitations due to physical health improved from 41.78±39.17 to 75.35±33.91 (p<0.001). 3. Score for the role limitations due to emotional problems improved from 48.07±42.32 to 80.46±33.81 (p<0.001). 4. Energy/Fatigue score improved from 56.71±19.97 to 68.78±16.40 (p<0.001). 5. Emotional wellbeing score improved from 58.22±17.31 to 71.88±14.33 (p<0.001). 6. Social functioning score improved from 68.39±24.51 to 81.00±19.12 (p<0.001). 7. Pain score improved from 59.82±28.65 to 80.57±20.58 (p<0.001) and 8. General health score improved from 48.42±15.26 to 62.57±15.43 (p<0.001). This study shows that catheter ablation which can effectively cure the patients from the paroxysmal supraventricular tachycardia significantly improves physical, emotional and social health scores by eliminating the arrhythmia episodes and associated symptoms and anxiety in patients with paroxysmal supraventricular tachycardia irrespective of patient demographics and the type of the SVT.

[Hypothermia-induced ECG changes: characteristic, but not specific]

Hypothermia-induced J‑ or so-called Osborn waves can be detected under therapeutic hypothermia in approximately 20-40% of cases. The occurrence of J‑waves in the context of the targeted temperature management after cardiopulmonary resuscitation is characteristic, but not pathognomonic for hypothermia. An electrocardiographic diagnosis under hypothermia after cardiac arrest should always be done with caution due to the various hypothermia-associated electromechanical changes of the myocardium.

ANXIETY LEVELS IN PATIENTS WITH PAROXY-SMAL SUPRAVENTRICULAR TACHYCARDIA IN RELATION WITH THE PATIENT DEMOGRAPHICS, TYPE OF SUPRAVENTRICULAR TACHYCARDIA AND THEIR PERSONALITY TYPE

The aim of the study was to evaluate the incidence of different personality types and state and trait anxiety levels in patients with paroxysmal supraventricular tachycardia and their association with patients age, gender and the mechanism of the paroxysmal SVT. 62 patients with documented paroxysmal supraventricular tachycardia who underwent endocardial eletrophysiological study and catheter ablation of the paroxysmal SVT were included in the study. The patients were asked to fill out the Myers-Brigss Type Indicator and State-Trait Anxiety Inventory questionnaires and the results were analyzed and correlated with the arrhythmia mechanism determined during electrophysiological study and catheter ablation procedure, and the patients' demographics (age and gender). There was no significant difference in State (mean 41.53±13.51, p=0.893) or Trait (mean 44.70±12.62, p=0.315) anxiety scores according to gender although higher scores were found in females. Older patients (≥50 years old compared to <50 years old) had higher anxiety scores but with no statistical significance (p=0.344 for state anxiety and p=0.100 for trait anxiety). The patients with AVNRT had significantly higher Trait anxiety scores (mean 46.82±10.52) than the patients with AVRT or AT (mean 40.59±10.91) (p=0.032). State anxiety score was not significantly different between patients with different SVT types (p=0.706). Anxiety is an important factor to be considered in patients with paroxysmal supraventricular tachycardia. It doesn't seem to be associated with different personality types. Female and older patients tend to show higher anxiety levels. The atrioventricular Nodal Reentrant Tachycardia (AVNRT) is associated with significantly higher trait anxiety levels compared to other types of paroxysmal supraventricular tachycardia.

Ablation of frequent premature ventricular complex in an athlete

Premature ventricular complex are common findings in the exam of many athletes. There is no extensive scientific evidence in the management of this situation particularly when associated with borderline contractile function of the left ventricle. In this case report, we present a 35-year-old asymptomatic healthy athlete with high incidence (over 10,000 beats in 24 h) of premature ventricular complex and left ventricular dilatation with dysfunction, which persisted after a resting period of 6 months without training. We performed radiofrequency ablation of the premature ventricular complex focus. After 1-year follow-up, he was asymptomatic without arrhythmia and the left ventricle normalized its size and function as shown by echocardiogram and cardiac magnetic resonance.

Sequenom MassARRAY approach in the arrhythmogenic right ventricular cardiomyopathy post-mortem setting: clinical and forensic implications

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare cardiac disease characterized by myocardial fibrofatty replacement, which can lead to sudden death. Previous studies have described a reduction of plakoglobin (PKG) protein at the level of intercalated disks as the hallmark of ARVC. The main objective of this study was to investigate the involvement of desmosome mutations in the histological phenotype of ARVC. We performed a genetic analysis of ARVC cases, and histological characterization of ARVC heart tissue samples. We genetically analyzed 48 ARVC cases distributed into two groups: 42 human tissue heart samples with conclusive diagnoses of ARVC after post-mortem examination; and six DNA samples from peripheral blood of living patients who were clinically diagnosed. Sequenom MassARRAY analysis revealed three ARVC-associated variants in three patients in 42 tissue samples (7.14 %). Three individuals carried one single pathogenic mutation, p.R811S _PKP2, p.S824L_DSC2, and p.T526M_PKP2 in postmortem samples. In the living patients group, Sequenom MassARRAY revealed no mutation, however, later Sanger sequencing analysis identified three ARVC mutations in 2/6 patients not included in the Sequenom design. In post-mortem tissue samples we performed immunohistochemical labeling for desmosomal proteins and Connexin 43. This study revealed that PKP2 carriers present either absent or clearly reduced PKG immunolabeling, while the DSC2 carrier showed PKG immunolabeling similar to control samples. Immunolabeling for Cx43 did not show any differences compared to controls. The present Sequenom MassARRAY design is a useful tool for post-mortem genetic diagnosis of ARVC. Plakoglobin reduction occurs at intercalated disks, while other desmosome proteins and Cx43 remain unaltered.