Venous Vascular Closure System Versus Figure-of-Eight Suture Following Atrial Fibrillation Ablation - The STYLE-AF Study

BACKGROUND

Simplified ablation technologies for pulmonary vein isolation (PVI) are increasingly performed worldwide. One of the most common complications following PVI are vascular access-related complications. Lately, venous closure systems (VCS) were introduced into clinical practice, aiming to reduce the time of bedrest, to increase the patients' comfort and to reduce vascular access-related complications.

AIMS

To compare the safety and efficacy of using a VCS to achieve haemostasis following single shot PVI to the actual standard of care (figure-of-eight suture and manual compression (MC)).

METHODS

This is a prospective, multicentre, randomized, controlled, open-label trial performed at 3 German centres. Patients were randomized 1:1 to undergo haemostasis either by means of VCS (VCS group) or of a figure-of-eight suture and MC (F8 group). The primary efficacy endpoint was the time to ambulation, while the primary safety endpoint was the incidence of major periprocedural adverse events until hospital discharge.

RESULTS

A total of 125 patients were randomized. The baseline characteristics were similar between the groups. The VCS group showed a shorter time to ambulation (109.0 (82.0, 160.0) vs. 269.0 (243.8, 340.5) min; p<0.001), shorter time to haemostasis (1 (1, 2) vs. 5 (2, 10) min; p<0.001) and shorter time to discharge eligibility (270 (270, 270) vs. 340 (300, 458) min; p<0.001). No major vascular access related complication was reported in either group. A trend towards a lower incidence of minor vascular access related complications on the day of procedure was observed in the VCS group (7 (11.1%) vs. 15 (24.2%); p=0.063) as compared to the control group.

CONCLUSION

Following AF ablation, the use of a VCS results in a significantly shorter time to ambulation, time to haemostasis and time to discharge eligibility. No major vascular access related complications were identified. The use of MC and a figure-of-eight suture showed a trend towards a higher incidence of minor vascular access related complications.

Impact of very wide antral pulmonary vein isolation on esophageal temperature changes during pulsed field ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Esophageal thermal injury (ETI) is a serious drawback of available energy sources for atrial fibrillation (AF) ablation, especially on the posterior left atrial (LA) wall. Pulsed field ablation (PFA) is a novel non-thermal energy source with promising safety advantages over existing methods due to its unique myocardial tissue specificity sparing the esophagus.

Objective

To evaluate esophageal temperature changes during very wide antral pulmonary vein isolation (PVI) using the PFA system.

Methods

Thirteen consecutive AF patients (62% with paroxysmal AF; age: 61 years; 70% male) underwent first-time PFA under deep sedation. Eight pulse trains (2kV/2.5 sec, bipolar, biphasic, 4x basket/flower configuration each) were delivered to each pulmonary vein (PV). Extra pulse trains in the flower configuration were added for very wide antral circumferential ablation (vWACA). Continuous intraluminal esophageal temperature (TESO) was monitored with an S-shaped esophageal temperature probe.

Results

A median of 32 (IQR 32;32) and 8 (IQR 8;9) pulse trains for PVI and vWACA with a procedural time and catheter dwell time of 67 min (IQR 61-69) and 17 min (IQR 16-18) were applied. PFA with vWACA resulted in consecutive posterior LA wall isolation in 11/13 patients. Fluoroscopically, the esophagus coursed near the right PVs in 2/13, left PVs in 8/13 and mid-posterior wall position in 3/13 patients. Maximum TESO increase from baseline was 0.8 ±0.9 °C. However, no clinically relevant TESO changes occurred (Table 1). On short-term, all patients remained asymptomatic for sore throat, cough, or other symptoms potentially related to ETI. No esophago-duodenoscopy was necessary.

Conclusion

PFA of the PVs and lesion extension to the posterior LA wall demonstrated clinically non-significant TESO changes and has the potential to eliminate the risk of a thermal damage to the esophagus.

Very high-power short-duration temperature-controlled ablation for cavotricuspid isthmus block : the Fast-and-Furious CTI study

Funding Acknowledgements

Type of funding sources: None.

Background

Catheter ablation for typical right atrial flutter (AFL) provides an effective treatment associated with encouraging clinical outcome. The novel micro-electrode ablation catheter allows very high-power short-duration (vHP-SD, 90 W/4 sec) ablation and potentially offers the ability to perform a safe, effective and faster cavotricuspid isthmus (CTI) ablation.

Aims

We evaluated feasibility and efficacy of a vHP-SD (90 W/4 sec) temperature-controlled radiofrequency (RF) CTI ablation for AFL using a novel contact force (CF) sensing ablation catheter with micro-electrodes.

Methods

Fifteen consecutive patients (median age 75 years (interquartile range, IQR: 67, 79), 67 % male) with documented typical AFL were prospectively enrolled and underwent vHP-SD based CTI ablation (90 W/4 sec). Durability of CTI block was proven by pacing maneuvers from both sides of the ablation line.

Results

Complete CTI block using vHP-SD ablation was achieved in all patients (Figure 1). At median 23 (IQR 20; 39) RF applications over a median RF ablation time of 92 (IQR 78, 154) seconds were applied. It was not necessary to switch to the standard temperature-controlled mode to achieve durable CTI block. No periprocedural complications, no charring and no steam pops were observed.

Conclusions

Very high-power short-duration (90 W/4 sec) CTI ablation for the treatment of typical AFL is feasible and efficient. Effective CTI block can be achieved in about 1.5 minutes of RF time.

Comparison of ostial versus very wide antral circumferential pulmonary vein isolation using pulsed field ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Pulmonary vein isolation (PVI) is the gold standard for first-time atrial fibrillation (AF) ablation procedures. Wide antral circumferential ablation (WACA) in comparison to ostial PVI has been attributed to an improved rhythm outcome after AF ablation. Pulsed field ablation (PFA) is a novel energy source with promising safety and efficacy advantages over existing ablation methods due to its unique myocardial tissue specificity. Feasibility of PFA for very WACA has not been investigated so far.

Objective

To evaluate procedural characteristics and lesion formation during wide antral circumferential PVI in comparison to ostial PVI using a PFA system.

Methods

Thirty-seven consecutive AF patients underwent first-time PFA under deep sedation. Patients eighter received ostial (ostial group; N = 15: 66 % paroxysmal AF; age: 69 years; 66 % male) or very wide antral (vWACA group; N = 22: 59 % paroxysmal AF; age: 62 years; 73 % male) PFA. Pre and post ablation LA voltage maps were acquired using a 20-pole spiral catheter together with a 3-dimensional electroanatomic mapping system (voltage cutoff ≤0.5 mV). On post ablation maps, lesion size by encircling the ablated area was measured. In all patients, 8 pulse trains (2kV/2.5 sec, bipolar, biphasic, 4x basket/flower configuration each) were delivered to each pulmonary vein (PV). In the vWACA-group, extra pulse trains in flower configuration were added to each PV in a wide antral position continuous intraluminal esophageal temperatures (TESO) were monitored with an S-shaped esophageal temperature probe.

Results

A median of 8 [IQR 8;8] and 10 [IQR 10;11] pulse trains per PV for ostial and vWACA PVI were applied. vWACA PFA resulted in significant larger lesion formation (47.3 cm2 [IQR 39.1; 52.0]) in comparison to ostial PFA (35.5 cm2 [IQR 30.3; 38.1], p=0.013) with consecutive posterior LA wall isolation in 19/22 (86 %) patients (Figure 1). In the vWACA group, median TESO increased by 0.7 °C (TESOmax 36.5 °C [IQR 36.0;36.9]). However, the vWACA approach was not associated with a significant increase in procedure time, sedation dosage or exposure to radiation.

Conclusion

Very wide antral circumferential PFA of the PVs is feasible and was associated with significant larger lesion formation in comparison to conventional ostial PFA. Concomitant posterior LA wall isolation occurred in the majority of patient and did not result in a clinically significant increase of intraluminal esophageal temperatures, procedure time, sedation and radiation dosage.

Acute procedural characteristics, efficacy, and safety of a novel cryoballoon for the treatment of paroxysmal atrial fibrillation: Results from the POLAR-ICE study

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Boston Scientific

Background/Introduction

Pulmonary vein isolation (PVI) using a cryoballoon is well-established for the treatment of paroxysmal atrial fibrillation (PAF). Initial experience with a novel cryoballoon (CB) with a stable low balloon pressure (POLARx, Boston Scientific) has demonstrated acute procedural safety and efficacy in de novo PVI procedures in patients with paroxysmal AF. However, to date, there is limited multicenter data on real world acute outcomes and procedural characteristics with this novel cryoballoon.

Purpose

The purpose of POLAR ICE was to provide real-world data on the acute and chronic outcomes of cryoballoon ablation with POLARx for the treatment of PAF. Here we report on the initial acute outcomes up to 3 months including procedural efficacy, safety, and biophysical parameters.

Methods

POLAR ICE, a prospective, non-randomized, multicenter (international) registry (NCT04250714), enrolled 400 patients across 19 centers, between Aug 2020 and May 2021. This study included any patients indicated for treatment of PAF with the POLARx cryoablation system. The study protocol did not mandate any specific cryodosing regimen, this was left to the operator. Procedural characteristics, such as time to isolation (TTI), cryoablations per pulmonary vein, balloon nadir temperature, and occlusion grade were recorded. PVI was confirmed with entrance block testing.

Results

Complete PVI was achieved in 96.1% of PVs (1437/1496). Procedure and fluoroscopy times were 69.0±25.2 min and 15.8±10.0 min, respectively. Left atrial dwell time was 47.3±18.8 min. The cryoablation characteristics by vein are shown in the Table 1. An average of 4.9±1.8 ablations were performed per patient (1.3±0.7 per vein). Grade 3 or 4 occlusion was achieved in 98.1% of PVs reported. Electrical isolation was achieved with an average TTI of 50±33.8s and in 81.4% of PVs isolation required only a single cryoablation. Nadir temperatures across all pulmonary veins averaged -56.3± 6.5C. Time to -40C was 32.9±11s and Time to Thaw (0C) was 19.5±6.7s across all veins. PVI was performed on atypical anatomies (12 LCPV, 7 RMPV, & 3 RCPV) in 19 pts. Serious adverse events included phrenic nerve palsy (0.5%), tamponade (0.5%), AV block (0.3%), stroke (0.3%), and transient ischemic attack (0.3%).

Conclusions

Real world usage data on the novel CB suggests that this device is safe and effective, with a PV isolation success rate of 96.2% and 81.4% of PVs isolated with a single cryoablation. These data are in keeping with reports on other cryoballon systems and have markedly shorter procedure times than have been previously reported on this cryoballon.

S-ICD in heart failure patients: real-world data from a multicenter, european analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Data on patients with heart failure (HF) and subcutaneous implantable cardioverter defibrillator (S-ICD) are very scarce and limited to a single prospective analysis from the UNTOUCHED trial.

Purpose

Aim of this study was to assess clinical outcomes of the S-ICD in HF patients, comparing them with a no-HF population, in a real-world analysis from the largest European retrospective S-ICD registry (ELISIR registry).

Methods

All consecutive patients undergoing S-ICD implantation at 20 European institutions enrolled in the ELISIR registry were used for the current analysis. According to European Guidelines, the registry population was classified into two groups: the HF cohort (further classified as HF with reduced and mid-range ejection fraction – HFrEF and HFmrEF) vs the no-HF group. The primary outcome of the study was the inappropriate shock (IS) rate across the two cohorts. As secondary outcomes, appropriate shocks, cardiovascular mortality and device-related complications during follow-up were assessed.

Results

A total of 1409 patients from the ELISIR registry were included in this analysis; HF patients represented 57.3% of the entire cohort (n=701, 86.9% HFrEF; n=106,13.1% HFmrEF). As expected, the HF cohort showed significantly higher rates of cardiovascular risk factors and comorbidities when compared to the no-HF cohort. Over a median follow-up of approximately 2 years, a total of 133 inappropriate shocks were observed in the entire cohort, without significant differences among the two groups (9.2% vs 9.8%, p=0.689). 133 complex ventricular arrhythmias were adequately recognized and treated in the overall cohort, showing similar rates of appropriate shocks (9.2% vs 9.8%, p=0.689). Inappropriate and effective shocks-free survival has been represented in Figure 1, showing Kaplan-Meier estimates comparing HF vs no-HF patients, also stratified by left ventricular ejection fraction (LVEF). The impact of baseline and procedural characteristics on the primary outcome was tested through univariable and multivariable Cox regression analysis in HF patients; at multivariate analysis, only age (HR=0.974 [0.955–0.992], p=0.005), LVEF (HR=0.954 [0.926-0.984], p=0.003), ARVC (HR=3.364 [1.206-9.384], p=0.020) and smart pass algorithm "on" (HR=0.321 [0.184-0.560], p&lt;0.001) remained associated with inappropriate shocks (Figure 2). A low number of patients (n=76) experienced device-related complications, more frequently in the HF cohort (6.2% vs 3.8%, p=0.031) with no significant differences regarding any specific outcome of interest: lead infection (1.1% vs 0.7%, p=0.381), pocket infection (1.9% vs 0.8%, p=0.107), pocket hematoma (3.2% vs 2.8%, p=0.668).

Conclusion

The rate of inappropriate shocks seems to be comparable in both HF and non-HF patients implanted with S-ICD. However, the rate of device-related complications was slightly more frequent in HF patients.

Age-related differences and associated outcomes of S-ICD: insights from a large, european, multicenter, real-world registry

Funding Acknowledgements

Type of funding sources: None.

Background

Young patients often represent the most suitable candidates for an entirely subcutaenous implantable cardioverter defibrillator (S-ICD) system, since they have to face a lifetime of device therapy and they rarely have a pre-existing or concurrent pacing or cardiac resynchronization therapy (CRT) indication. Moreover, S-ICD offers lower rate and a safer management of lead and major procedure-related complications. To date, a few limited case series and experiences with S-ICD in teenagers and young adults have shown that the S-ICD system is safe and feasible in this population, with a rate of inappropriate shocks (IS) comparable to transvenous (TV) ICD, but focused analysis on a large scale are currently lacking in this setting.

Purpose

The aim of the current study was to compare the age-related differences observed in patient selection, baseline characteristics, and device long-term associated outcomes in a large real world cohort of S-ICD recipients. The primary outcome of the study was defined as the comparisons of the IS rate observed during the entirety of follow up in the teenagers/young adult vs the adult populations. Rate of complications, freedom from sustained ventricular arrhythmic events, overall and cardiovascular mortality were also assessed in the two cohorts and assessed as secondary outcomes.

Methods

All S-ICD recipients in the ELISIR project were enrolled in the current study. Patients were classified into teenagers + young adults (≤ 30 years old) vs adults (&gt; 30 years old), depending from patient age at device implantation (Figure 1). Rates of device-related complications and IS were compared between the cohorts.

Results

A total of 1349 patients were extracted from the ELISIR project. Teenagers and young adults represented 12.4% of the registry (n=56 teenagers; n=112 young adults). Patients were followed-up for a median of 23.1 [12.6–37.9] months. Overall, 117 (8.7%) patients experienced inappropriate S-ICD shocks and 100 (7.4%) device related complications were observed, with no age-related differences. IS resulted more frequent in the teenager and young adult cohort (14.3% vs 7.9%; p=0.006). Figure 2 reports Kaplan Meier curves for the occurrence of IS. At univariate analysis, young age was associated with IS, but after correcting for differences in arrhythmic substrate, this association resulted non-significant (aHR: 1.428 [0.883–2.331]; p=0.146). The use of SMART pass algorithm was instead associated to a strong reduction in IS (aHR 0.367 [0.245–0.548]; p&lt;0.001).

Conclusion

The use of S-ICD in teenagers/young adults resulted safe and effective. Indeed, the rate of complications between teenagers/young adults and adults was not significantly different. Although a higher rate of IS was observed in the teenagers/young adults, when accounting for differences in baseline substrate and comorbidities, young age did not result associated with an increased risk of IS.

C9 SUBCUTANEOUS IMPLANTABLE CARDIOVERTER DEFIBRILLATOR IN PATIENTS WITH LOW BMI: REAL–WORLD DATA FROM A EUROPEAN MULTICENTER ANALYSIS

Background

One of the current limitations of the S–ICD is the relatively large size of the generator compared to the TV (transvenous) ICD. There is little evidence whether the size of the current S–ICD generator is associated with an elevated risk of device–related complications in patients with a low body mass index (BMI).

Purpose

Aim of this study was to compare the device–related complications and long–term outcomes in a large real world cohort of S–ICD recipients in patients with a BMI &lt;18 kg/m2 compared to patients with a BMI &gt;18 kg/m2.

Methods

All consecutive patients meeting current guideline indications for ICD implantation and undergoing implantation of a S–ICD device (Boston Scientific, Marlborough, Massachusetts, USA) at 21 European institutions enrolled in the extended ELISIR registry were used for the current analysis. Patients were classified into two cohorts, depending on the BMI at the time of device implantations: BMI &lt; 18 kg/m2 versus &gt; 18 kg/m2.

Results

Out of a total of 1497 pts, 58 pts (3.9%) had a BMI &lt; 18 kg/m2. Patients with BMI &lt;18 kg/m2 were younger (44.6±2.4 vs 50.8±0.4; p = 0.004) and more frequently female (58.6% vs 22.3%, p &lt; 0.001). No differences in any of the other baseline characteristic were observed. Implantation techniques resulted comparable between the groups (rates of 2–incision technique: 87.8% vs 91.9%; p = 0.256; inter–muscular placement: 89.7% vs 83.3%; p = 0.198). Of note, the mean PRAETORIAN score at implantation of patients with BMI &lt;18 kg/m2 was significantly lower (33.8±9.1 vs 54.1±47.3; p = 0.035), although the vast majority of patients in both cohorts qualified as at low risk of conversion failure (100% vs 91.4%; p = 0.436). Over a median follow up time of 22.4 [11.6–36.8] months, both overall device–related complications (5.2% vs 7.4%) and rates of inappropriate shocks (12.0% vs 8.8%) resulted comparable between the two groups (p = 0.517 and p = 0.385, respectively). Figure 1 reports Kaplan–Meier curves showing the combined incidence of device–related complications and inappropriate shocks in the two groups (log–rank p = 0.576).

Conclusion

No differences in device–related complications and long–term outcomes after S–ICD implantation were observed in patients with BMI &lt;18 kg/m2 compared to the remaining recipients in a large multicentered real–world analysis.

P21 AGE–RELATED DIFFERENCES AND ASSOCIATED OUTCOMES OF S–ICD: INSIGHTS FROM A LARGE, EUROPEAN, MULTICENTER REGISTRY

Background

The subcutaneous implantable cardioverter defibrillator (S–ICD) has become an alternative to transvenous ICDs (TV–ICD) in patients who do not need pacing. To date, there is little evidence directly comparing the rates of inappropriate shocks (IAS) in young vs old S–ICD recipients.

Purpose

Aim of our study was to assess differences in device–related complications and inappropriate shocks (IS) between teenagers/young adults and adult recipients of a subcutabeous implantable cardioverter defibrillator (S–ICD) device.

Methods

Two propensity–matched cohorts of teenagers + young adults (≤ 30–year–old) and adults (&gt; 30–year–old) were retrieved from the ELISIR registry. The primary outcome was the comparison of the inappropriate shock (IAS) rate; complications, freedom from sustained ventricular arrhythmic events, overall and cardiovascular mortality were deemed secondary outcomes.

Results

A total of 1491 patients were extracted from the ELISIR project. Teenagers + young adults represented 11.0% of the entire cohort. Two propensity–matched groups of 161 patients each were used for the analysis (Figure 1); median follow–up was 23.1 [13.2–40.5] months. 15.2% patients experienced inappropriate S–ICD shocks and 9.3% device related complications were observed with no age–related differences in IAS (16.1% vs 14.3%; p = 0.642) and complication rates (9.9% vs 8.7%; p = 0.701); Figure 2 shows a survival analysis from inappropriate shocks in the teen–ager/young adult cohort (red) and in the adult cohort (blue). At univariate analysis, young age was not associated with increased rates of IAS (HR 1.204 [0.675–2.148]: p = 0.529). At multivariate analysis (Figure 3), the use of SMART pass algorithm was associated to a strong reduction in IAS (aHR 0.292 [0.161–0.525]; p &lt; 0.001), while ARVC was associated with higher rates of IAS (aHR 2.380 [1.205–4.697]; p = 0.012).

Conclusion

In a large multicentered European registry of patients with S–ICD, 11.0% of all recipients were teenagers or young adults. The use of S–ICD in teenagers/young adults resulted safe and effective, and the rates of complications and IAS between teenagers/young adults and adults were not significantly different. The only predictor of increased IAS was a diagnosis of ARVC.

P25 SUBCUTANEOUS–ICD IN PATIENTS WITH HEART FAILURE: RESULTS FROM A MULTICENTER, EUROPEAN ANALYSIS

Background

Data on patients with heart failure (HF) with a subcutaneous implantable cardioverter defibrillator (S–ICD) are scarce.

Objective

Aim of this study was to assess clinical outcomes of the S–ICD in HF patients in a real–world analysis from the largest European retrospective S–ICD registry (ELISIR).

Methods

All consecutive patients undergoing S–ICD implantation at several European institutions were used for the current analysis. The population was classified into two groups: the HF (classified as HF with reduced and mid–range ejection fraction – HFrEF and HFmrEF) vs the no–HF cohort. The primary outcome of the study was the inappropriate shock (IS) rate across the two cohorts. As secondary outcomes, appropriate shocks, cardiovascular mortality and device–related complications during follow–up were assessed

Results

A total of 1409 patients from the ELISIR registry were included; HF patients represented 57.3% of the entire cohort (n = 701, 86.9% HFrEF; n = 106,13.1% HFmrEF). Over a median follow–up of approximately 2 years, a total of 133 inappropriate shocks were observed in the entire cohort, without significant differences among the two groups (9.2% vs 9.8%, p = 0.689). 133 complex ventricular arrhythmias were adequately recognized and treated, with similar rates of appropriate shocks (9.2% vs 9.8%, p = 0.689). Inappropriate and effective shocks–free survival has been represented in Figure 1 (Kaplan–Meier estimates). At multivariate analysis (Figure 2), age (HR = 0.974 [0.955–0.992], p = 0.005), LVEF (HR = 0.954 [0.926–0.984], p = 0.003), arrhythmogenic right ventricular cardiomyopathy – ARVC (HR = 3.364 [1.206–9.384], p = 0.020) and smart pass + (HR = 0.321 [0.184–0.560], p &lt; 0.001) remained associated with inappropriate shocks. Moreover, a low number of patients (n = 76) experienced device–related complications, more frequently in the HF cohort (6.2% vs 3.8%, p = 0.031) with no significant differences regarding any specific outcome of interest: lead infection (1.1% vs 0.7%, p = 0.381), pocket infection (1.9% vs 0.8%, p = 0.107), pocket hematoma (3.2% vs 2.8%, p = 0.668).

Conclusion

The use of S–ICD in HF patients did not result in a higher rate of inappropriate shocks when compared to no–HF patients, even when stratifying for LVEF. Only age, LVEF, ARVC e Smart Pass algorithm were predictors of the primary outcome at multivariate analysis. Despite a lower overall rate of complications in the entire cohort, HF patients experienced device–related complications more frequently.

P1438Predictors and clinical impact of bleeding events after left atrial appendage closure in patients with high risk or a history of bleeding

Background

Left atrial appendage closure (LAAC) has emerged as an alternative to oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation and may be especially attractive in patients with high risk or a history of bleeding. However, data of clinical benefit and incidence of post-procedural bleeding in patients with both high risk of bleeding and ischemic cerebral stroke after LAAC are lacking.

Objectives

This study sought to identify predictors and the prognostic impact of post-LAAC bleeding in patients at high risk and/or history of bleeding in the direct oral anticoagulant therapy (DOAC) era.

Methods and results

We retrospectively enrolled a total of 195 patients (75 ± 8.7 years, 38% female, 47% with previous major bleeding, mean CHA2DS2-VASc score 4.3 ± 1.6 and mean HAS-BLED score 2.7 ± 1.1) undergoing endocardial (91%) or epicardial (9%) LAAC during a mean follow-up of 339 ± 319 days. Twenty-three (11.9%) patients developed procedure-unrelated bleeding events after a median of 147 (43, 362) days after LAAC, in 12/23 (52%) patients under single antiplatelet therapy (SAPT), 6/23 (26%) dual antiplatelet therapy (DAPT), 1/23 (4%)  DOAC, 1/23 (4%) VKA, 2/23 (9%) dual therapy (SAPT and DOAC/VKA) and 1/23 (4%) triple therapy (DAPT and DOAC/VKA). (Figure) Diabetes mellitus and previous major bleeding were identified as the independent predictors of post-LAAC bleeding (Odds ratio 2.65 [95% CI:1.04-6.73], p = 0.041, and 5.50 [95% confidence interval:1.72-17.5], p = 0.004). Post-LAAC bleeding was associated with all-cause death (9/23 [39%] vs 18/171 [11%], p = 0.001), but not ischemic stroke/TIA (1/23 [4%] vs 6/171 [4%], p = 0.593) nor device thrombus (2/23 [9%] vs 3/171 [2%], p = 0.108). Kaplan-Meier curve estimated that patients with post-LAAC bleeding had a worse mortality than those without post-LAAC bleeding (3-year mortality; 35.6% [95%CI; 11.6-61.0%] vs 68.7% [45.0-83.8], p = 0.029)

Conclusions

In AF patients with high bleeding risk or history of bleeding undergoing LAAC, bleeding events are common and may occur even after long-term duration after LAAC. Previous major bleeding history strongly predicts subsequent bleeding events following LAAC and is associated with unfavorable mortality. Further investigations are required to identify optimal post-procedural antithrombotic strategies for patients undergoing LAAC with previous major bleeding.

Abstract Figure. The association between time to bleeding

P2846Focal impulse and rotor modulation ablation versus pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation (FIRMAP AF study)

Background

Based on the assumption of trigger elimination, pulmonary vein isolation (PVI) currently presents the gold standard of atrial fibrillation (AF) ablation. Recently, rapidly spinning rotors or focal impulse formation has been raised as a crucial sustaining mechanism of AF. Ablation of these rotors may potentially obviate the need for trigger elimination with PVI.

Purpose

This study sought to compare the safety and effectiveness of Focal Impulse and Rotor Modulation (FIRM) guided catheter ablation only with the gold standard of pulmonary vein isolation (PVI) in patients with paroxysmal AF.

Methods

This was a post-market, prospective, single-blinded, randomized, multi-center trial. Patients were enrolled at three centers and equally (1:1) randomized between those undergoing conventional RF ablation with PVI (PVI group) vs. those treated with FIRM-guided RF ablation without PVI (FIRM group). Data was collected at enrollment, procedure, and at 7-day, 3-month, 6-month, and 12-month follow-up visits. The study was closed early by the sponsor. At the time of study closure, any pending follow-up visits were waived.

Results

From February 2016 until February 2018, a total of 51 (out of a planned 170) patients (mean age 63±10.6 years, 57% male) were enrolled and randomized. Four patients withdrew from the study prior to treatment, resulting in 23 patients allocated to the FIRM group and 24 in the PVI group. Only 13 patients in the FIRM group and 11 patients in the PVI group completed the 12-month follow-up. Statistical analysis was not completed given the small number of patients.

Single-procedure effectiveness (freedom from AF/atrial tachycardia recurrence after blanking period) was 52.9% (9/17) in the FIRM group and 85.7% (12/14) in the PVI group at 6 months; and 31.3% (5/16) in the FIRM group and 80% (8/10) in the PVI group at 12 months. Repeat procedures were performed in 45.8% (11/24) patients in the FIRM group and 7.4% (2/27) in the PVI group.

The acute safety endpoint [freedom from procedure-related serious adverse events (SAE)] was achieved in 87% (20/23) of FIRM group patients and 100% (24/24) of PVI group patients. Procedure related SAEs occurred in three patients in the FIRM group: 1 femoral artery aneurysm and 2 injection site hematomas. No additional procedure-related SAEs were reported >7 days post-procedure.

Conclusions

These partial study effectiveness results reinforce the importance of PVI in paroxysmal atrial fibrillation patients and suggest that FIRM-guided ablation alone (without PVI) is not an effective strategy for treatment of paroxysmal AF in most patients. Further study is needed to understand the effectiveness of adding FIRM-guided ablation as an adjunct to PVI in this patient group.

Acknowledgement/Funding

Abbot

P343Comparison of Focal Impulse and Rotor Modulation Ablation (FIRM) only versus second-generation cyroballoon ablation in patients with paroxysmal atrial fibrillation

Background

Rotors have been postulated to be a major driver of atrial fibrillation (AF). Initial studies demonstrated, that focal impulse and rotor modulation (FIRM) might be an effective therapy for the treatment of paroxysmal AF (PAF). However, data about FIRM-guided ablation strategies without PVI is sparse.

Objective

To compare the safety and efficacy of FIRM-guided catheter ablation (without PVI; FIRM arm) and second generation cryoballoon (CB2, CB2 arm) based PVI in patients with paroxysmal atrial fibrillation (PAF) and de-novo catheter ablation of AF.

Methods

In this retrospective single-center study patients with PAF undergoing de-novo ablation of PAF between February 2016 and January 2017 were enrolled. Patients treated with FIRM-guided AF ablation as a standalone therapy without PVI were included and compared with patients undergoing CB2 based PVI. All patients in the FIRM arm were part of the randomized multicenter FIRMAP AF trial (results of this trial will be presented at this meeting). In patients undergoing FIRM-guided ablation, 3D electroanatomical mapping of both atria was performed. Rotor mapping using FIRM technology was conducted in spontaneous or induced AF. The procedural endpoint was the elimination of all rotors and focal impulses; no PVI was performed in those patients. In the CB2 arm, CB based PVI with the procedural endpoint of isolation of all veins was performed. Procedural data and arrhythmia-free survival after 12 months were compared.

Results

FIRM-guided and CB2 based AF ablation was performed in 22 and 86 patients, respectively. Follow up was completed in 20 and 79 patients LA diameter differed between groups. Otherwise, baseline characteristics did not differ between the FIRM group (mean age 60±11 years, 59.1% males) and the CB2 group (mean age 62±13, 62.4% male).

Arrhythmia-free survival including a 90-day blanking period was 25.0% (15/20) in the FIRM group and 86.1% (11/79) in the CB2 PVI group (p=0.000; Figure 1). Procedure duration was significantly longer in the FIRM group (152 [120; 176] minutes) compared to the CB2 PVI group (122 [110; 145] minutes) (p=0.031), whereas radiation dose was lower in the FIRM group (1266 [1027; 2281] cGy·cm2 vs. 3020 [1677; 4215] cGy·cm2). Adverse events (groin complications) occurred in 1 patient (1.2%) in the CB2 PVI group and 5 patients (22.7%) in the FIRM group.

Figure 1. Kaplan-Meier-survival curve dem

Conclusion

De novo ablation of PAF using a FIRM-guided AF ablation only (without PVI) is associated with poor arrhythmia-free survival after 12 months compared to CB2 PVI. These results underline the importance of PVI as the first-line approach in catheter ablation of AF.

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

[Ablation of supraventricular tachycardias : Complications and emergencies]

Catheter ablation is an established treatment of supraventricular tachycardias (SVT) with high success rates of > 95 %. Complication rates range from 3 to 5 %, with serious complications occurring in about 0.8 %. There are general complications caused either by the vascular access or the catheters (e. g. hematomas, hemo-pneumothorax, embolism, thrombosis and aspiration) und specific ablation related complications (e. g. AV block during ablation of the slow pathway). The complication risk is elevated in elderly and multimorbid patients. Furthermore, the experience of the treating physician and the respective team plays an essential role. The purpose of this article is to give an overview on incidences, causes and management as well as prevention strategies of complications associated with catheter ablation of SVT.

What have we learned of ablation procedures for atrial fibrillation?

Atrial fibrillation is a widespread disease of growing clinical, economic and social importance. Interventional therapy for atrial fibrillation offers encouraging results, with pulmonary vein isolation (PVI) as the established cornerstone. Yet, the challenge to create durable transmural lesions remains, leading to recurrence of atrial fibrillation in long-term follow-up even after multiple ablation procedures in 20% of patients with paroxysmal atrial fibrillation and approximately 50% with persistent atrial fibrillation. To overcome these limitations, innovative tools such as the cryoballoon and contact force catheters have been introduced and have demonstrated their potential for safe and effective PVI. Furthermore, advanced pharmacological and pacing manoeuvres enhance evaluation of conduction block in PVI.

Pulmonary vein triggers, focal sources, rotors and atrial cardiomyopathy: implications for the choice of the most effective ablation therapy

Understanding of the pathophysiological mechanism(s) underlying atrial fibrillation (AF) is the foundation on which current ablation strategies are built. In the vast majority of patients with paroxysmal AF, the ablation procedure should target the pulmonary veins. In patients with nonparoxysmal AF, however, pulmonary vein isolation alone seems to be insufficient to prevent the arrhythmia. Several recent clinical trials have investigated the concept that rotors (re-entry based on a meandering central core from which spiral waves emanate) might be the mechanism responsible for sustaining AF. Ablation of these localized AF sources is an important step towards substrate-driven procedures in persistent AF. Hybrid AF ablation procedures, based on the integration of endocardial transcatheter and epicardial off-pump surgical techniques, have been introduced to overcome their mutual shortcomings. The long-term results are encouraging, especially in currently challenging settings such as nonparoxysmal AF and failed endocardial catheter ablation procedures.