Safety and Effectiveness of Pulsed Field Ablation to Treat Atrial Fibrillation: One-Year Outcomes From the MANIFEST-PF Registry.

BACKGROUND: Pulsed field ablation is a novel nonthermal cardiac ablation modality using ultra-rapid electrical pulses to cause cell death by a mechanism of irreversible electroporation. Unlike the traditional ablation energy sources, pulsed field ablation has demonstrated significant preferentiality to myocardial tissue ablation, and thus avoids certain thermally mediated complications. However, its safety and effectiveness remain unknown in usual clinical care. METHODS: MANIFEST-PF (Multi-National Survey on the Methods, Efficacy, and Safety on the Post-Approval Clinical Use of Pulsed Field Ablation) is a retrospective, multinational, patient-level registry wherein patients at each center were prospectively included in their respective center registries. The registry included all patients undergoing postapproval treatment with a multielectrode 5-spline pulsed field ablation catheter to treat atrial fibrillation (AF) between March 1, 2021, and May 30, 2022. The primary effectiveness outcome was freedom from clinical documented atrial arrhythmia (AF/atrial flutter/atrial tachycardia) of ≥30 seconds on the basis of electrocardiographic data after a 3-month blanking period (on or off antiarrhythmic drugs). Safety outcomes included the composite of acute (<7 days postprocedure) and latent (>7 days) major adverse events. RESULTS: At 24 European centers (77 operators) pulsed field ablation was performed in 1568 patients with AF: age 64.5±11.5 years, female 35%, paroxysmal/persistent AF 65%/32%, CHA2DS2-VASc 2.2±1.6, median left ventricular ejection fraction 60%, and left atrial diameter 42 mm. Pulmonary vein isolation was achieved in 99.2% of patients. After a median (interquartile range) follow-up of 367 (289-421) days, the 1-year Kaplan-Meier estimate for freedom from atrial arrhythmia was 78.1% (95% CI, 76.0%-80.0%); clinical effectiveness was more common in patients with paroxysmal AF versus persistent AF (81.6% versus 71.5%; P=0.001). Acute major adverse events occurred in 1.9% of patients. CONCLUSIONS: In this large observational registry of the postapproval clinical use of pulsed field technology to treat AF, catheter ablation using pulsed field energy was clinically effective in 78% of patients with AF.

Acute oesophageal safety and long-term follow-up of AI-guided high-power short-duration with 50 W for atrial fibrillation ablation.

AIMS: Pulmonary vein isolation using radiofrequency ablation is an effective treatment option for patients with symptomatic atrial fibrillation (AF). Application of high power over a short period of time (HPSD) is reported to create more efficient lesions and may prevent collateral thermal oesophageal injury. This study aims to compare efficacy and safety of two different HPSD ablation approaches using different ablation index settings. METHODS AND RESULTS: Consecutive patients undergoing AF ablation with HPSD (50 W; ablation index-guided) using the ThermoCool SmartTouch SF catheter were included. Patients were grouped by ablation protocol: ablation with target ablation index (AI) of 400 on the anterior left atrial wall vs. 300 at the posterior left atrial wall (AI 400/300) or AI 450/350 was performed upon the operator's preference and compared. Peri-procedural parameters and complications were recorded, and incidences of endoscopically detected thermal oesophageal lesions (EDEL) analysed. Recurrence rates after a mean follow-up of 25 ± 7 months and reconnection patterns in patients undergoing redo procedures were investigated. A total of 795 patients (67 ± 10 years; 58% male; 48% paroxysmal AF) underwent a first AF ablation with HPSD (211 in group AI 400/300 and 584 in group 450/350). Median procedure time was 82.9 ± 24.6 min with longer ablation times in patients with target AI 400/300 due to higher intraprocedural reconnection rates, increased box lesions, and additional right atrial isthmus ablations. EDEL rates among target AI 400/300 procedures were significantly lower (3% vs. 7%; P = 0.019). Correspondingly, AI 450/350 was the strongest independent predictor of post-ablation EDEL (OR 4.799, CI 1.427-16.138, P = 0.011). Twelve-month (76% vs. 76%; P = 0.892) and long-term ablation single procedure success (68% vs. 71%; log-rank P = 0.452) after a mean of 25 ± 7 months were comparable among both target AI groups; however, long-term success was significantly higher for paroxysmal AF compared to persistent AF (12 months: 80% vs. 72%; P = 0.010; end of follow-up: 76% vs. 65%; log-rank P = 0.001). One hundred three patients (16%) underwent a redo procedure during follow-up documented comparable pulmonary vein (PV) reconnection among groups. Multivariate predictors of AF recurrence were age, left atrium (LA) size, persistent AF, and extra-PV ablation targets. CONCLUSION: High-power short-duration AF ablation with target AI of 400 for non-posterior wall and 300 for posterior wall lesions resulted in comparable long-term results compared to higher AI (450/350) ablations with significantly lower risk for thermal oesophageal lesions. Older age, larger LA size, persistent AF, and extra-PV ablation targets were identified in a multivariate analysis as independent risk factors for recurrences of atrial arrhythmias.

Case report: Epicardial ligation of the left atrial appendage in a patient with an inaccessible left atrial cavity.

It has been shown that endocardial occlusion of the left atrial appendage (LAA) is equally effective in preventing embolic events compared to oral anticoagulation in patients with nonvalvular atrial fibrillation. An 82-year-old female patient was admitted for LAA occlusion for repetitive GI bleeding. She had high CHADSVASC Score and HASBLED with long persistent atrial fibrillation with many comorbities. The preprocedural transesophageal echo revealed a great mass in the left atrium (Picture 1). Cardiac surgery was denied, we performed an epicardial only ligation for closing the LAA. For this approach we performed an epicardial puncture and contrast injection within the pericardial space to delineate the LAA. An epicardial wire with a suction mechanism at its distal end was attached to the anterior lobe of the LAA. Using this epicardial wire the snare could be advanced over the appendage and closed down. Complete exclusion of the LAA was achieved. There were no procedural complications and the patient is doing well after 3 months.

Optimal cut-off value for endocardial bipolar voltage mapping using a multipoint mapping catheter to characterize the scar regions described in cardio-CT with myocardial thinning.

INTRODUCTION: To investigate whether the current standard voltage cut-off of <0.5 for dense scar definition on endocardial bipolar voltage mapping (EBVM), using a high-resolution multipoint mapping catheter with microelectrodes (HRMMC), correctly identifies the actual scar area described on CT with myocardial thinning (CT MT). METHODS: Forty patients (39 men; 67.0 ± 9.0 y/o) with a history of transmural myocardial infarction (mean time interval since MI 15.0 ± 7.9 years) and sustained ventricular tachycardia (VT) were consecutively enrolled. A CT MT was performed in each patient before VT ablation. The CT MT 3D anatomical model, including MT layers, was merged with the 3D electroanatomical and EBVM. Different predefined cut-off settings for scar definition on EBVM were used to identify the optimal ones, which showed the best overlap in terms of scar area with the different MT layers. RESULTS: A cut-off value of <0.2 mV demonstrated the best correlation in terms of scar area with the 2 mm thinning on CT MT (p = .04) and a cut-off of <1 mV best overlapped with the 5 mm thinning (p = .003). The currently used <0.5 mV cut-off for scar definition on EBVM proved to be the best area correlation with 3 mm thinning (p = .0002). CONCLUSION: In order to better identify the real extent of scar areas after transmural MI as described on preprocedural CT MT, higher cut-off values for scar definition should be applied if the EBVM is performed using a HRMMC.

Efficacy and safety of high-power short duration atrial fibrillation ablation in elderly patients.

INTRODUCTION: Data about atrial fibrillation (AF) ablation using high-power short duration (HPSD) radiofrequency ablation in the elderly population is still scarce. The aim of our study was to investigate the efficacy and safety of HPSD ablation in patients over 75 years compared to younger patients. METHODS: Consecutive patients older than 75 years with paroxysmal or persistent AF undergoing a first-time AF ablation using 50 W HPSD ablation approach were analyzed in this retrospective observational analysis and compared to a control group <75 years. Short-term endpoints included intraprocedural reconnection of at least one pulmonary vein (PV) and intrahospital and AF recurrence during 3 months blanking period, as well as a long-term endpoint of freedom from atrial arrhythmias of antiarrhythmic drugs after 12 months. RESULTS: A total of 540 patients underwent a first AF ablation with HPSD (66 ± 10 years; 58% male; 47% paroxysmal AF). Mean age was 78 ± 2.4 and 63 ± 6.3 years (p < .001), respectively. Elderly patients were significantly more often women (p < .001). The procedure, fluoroscopy, and ablation were comparable. Elderly patients revealed significantly more often extra-PV low-voltage areas requiring additional left atrial ablations (p < .001). Overall complication rates were low; however, elderly patients revealed higher major complication rates mainly due to unmasking sick sinus syndrome (p = .003). Freedom from arrhythmia recurrences was comparable (68% vs. 76%, log-rank p = .087). Only in the subgroup of paroxysmal AF, AF recurrences were more common after 12 months (69% vs. 82%; log-rank p = .040; hazard ratio: 1.462, p = .044) in the elderly patients. In multivariable Cox regression analysis of the whole cohort persistent AF, female gender, diabetes mellitus and presence of left atrium low-voltage areas, but not age >75 years were associated with AF recurrences. CONCLUSION: HPSD AF ablation of patients >75 years in experienced centers is safe and effective. Therefore, age alone should not be the reason to withhold AF ablation from vital elderly patients due to only a slightly worse outcome and safety profile. In paroxysmal AF, elderly patients have more recurrences compared to the younger control group.

Radiofrequency ablation of atrial fibrillation-50 W or 90 W?

BACKGROUND: This study sought to evaluate the short and midterm efficacy and safety of the novel very high power very short duration (vHPvSD) 90 W approach compared to HPSD 50 W for atrial fibrillation (AF) ablation as well as reconnection patterns of 90 W ablations. METHODS AND RESULTS: Consecutive patients undergoing first AF ablation with vHPvSD (90 W; predefined ablation time of 3 s for posterior wall ablation and 4 s for anterior wall ablation) were compared to patients using HPSD (50 W; ablation index-guided; AI 350 for posterior wall ablation, AI 450 for anterior wall ablation) retrospectively. A total of 84 patients (67.1 ± 9.8 years; 58% male; 47% paroxysmal AF) were included (42 with 90 W, 42 with 50 W) out of a propensity score-matched cohort. 90 W ablations revealed shorter ablation times (10.5 ± 6.7 min vs. 17.4 ± 9.9 min; p = .001). No major complication occurred. 90 W ablations revealed lower first pass PVI rates (40% vs. 62%; p = .049) and higher AF recurrences during blanking period (38% vs. 12%; p = .007). After 12 months, both ablation approaches revealed comparable midterm outcomes (62% vs. 70%; log-rank p = .452). In a multivariable Cox regression model, persistent AF (hazard ratio [HR]: 1.442, 95% confidence interval [CI]: 1.035-2.010, p = .031) and increased procedural duration (HR: 1.011, 95% CI: 1.005-1.017, p = .001) were identified as independent predictors of AF recurrence during follow-up. CONCLUSIONS: AF ablation using 90 W vHPvSD reveals a similar safety profile compared to 50 W ablation with shorter ablation times. However, vHPvSD ablation was associated with lower rates of first-pass isolations and increased AF recurrences during the blanking period. After 12 months, 90 W revealed comparable efficacy results to 50 W ablations in a nonrandomized, propensity-matched comparison.

Safety aspects of very high power very short duration atrial fibrillation ablation using a modified radiofrequency RF-generator: Single-center experience.

INTRODUCTION: High power short duration (HPSD) ablation proved to be an effective and safe ablation technique for atrial fibrillation (AF). In former case series, a significant amount of postablation coagulation at the catheter tip as well as silent cerebral lesions (SCL) in postprocedural cerebral magnetic resonance (cMRI) have been identified in patients undergoing de-novo AF ablations with very high power 90 W short duration (vHPvSD) ablations using the QDot ablation catheter in combination with a novel RF generator (nGEN, Biosense Webster). Therefore, the RF generator software has been recently modified. METHODS AND RESULTS: Consecutive patients undergoing a first AF ablation including pulmonary vein isolation (PVI) with vHPvSD (90 W, with a predefined ablation time of 3 s at posterior left atrium (LA) wall sites and 4 s at other ablation sites) using the QDOT Micro ablation catheter (Biosense Webster) in conjunction with the technically modified nGEN RF generator (software V1c; Biosense Webster) were included. Procedural characteristics including first-pass isolation per pulmonary vein (PV) pair and early reconnection location within the 30-min waiting period were recorded. In all patients postablation endoscopy to document any thermal esophageal injury (EDEL) and in eligible patients a cMRI to detect silent cerebral events (SCEs)/lesions were performed. All acute procedure-related complications were recorded during the time until hospital discharge. Furthermore, short-term and midterm success after 3 and 6-12 months of follow-up was investigated. In total, 34 consecutive patients (67 ± 9 years; 62% male; 68% paroxysmal AF) were included. First-pass isolation of all PVs was achieved in 6/34 (18%) patients. First-pass isolation was seen in 37/68 (54%) of PV pairs. Early reconnection occurred in 11 (32%) patients (including reconnections at posterior LA wall sites n = 6 and at nonposterior sites n = 5). No patient had an EDEL (0%). In 6/23 (26%) patients undergoing postablation cerebral MRI SCEs were identified. In six patients, coagulation on the catheter tip was detected at the end of the procedure. No further peri- or postprocedural complications were detected. Early AF recurrence before discharge was seen in 1/34 (3%) of the patients included in this study. Within 3 months 10/34 (29%) revealed AF recurrence during blanking period. After a mean follow-up of 7 months, 31/34 (88%) patients revealed sinus rhythm. CONCLUSION: AF ablation using 90 W vHPvSD with a specialized ablation catheter in conjunction with a recently modified RF generator was associated with no EDEL in the whole study cohort and 26% SCEs in a subgroup of patients undergoing acute postablation cerebral MRI. Accordingly, to our previously published results, a relevant number of catheter tip coagulations was identified in this patient cohort even after modifications of the RF generator. The vHPvSD ablation technique using the present and the previous generator seems to be associated with a very low rate of esophageal injury. However, the recently revised generator software also produced a relevant number of catheter tip coagulum formation and SCEs.

Acute oesophageal safety of high-power short duration with 50 W for atrial fibrillation ablation.

AIMS: Pulmonary vein isolation (PVI) using radiofrequency (RF) ablation is an effective treatment option for patients with atrial fibrillation (AF). This study aims to investigate the safety of high-power short duration (HPSD) with emphasis on oesophageal lesions after PVI. METHODS AND RESULTS: Consecutive patients undergoing AF ablation with HPSD (50 W; ablation index (AI)-guided; target AI 350 for posterior wall ablation, AI 450 for anterior wall ablation) using the ThermoCool SmartTouch SF catheter were included. Patients underwent post-ablation oesophageal endoscopy to detect and categorize thermal oesophageal injury (EDEL). Occurrence and risk factors of oesophageal lesions and perforating complications were analysed. A total of 1033 patients underwent AF ablation with HPSD. Of them, 953 patients (67.6 ± 9.6 years; 58% male; 43% paroxysmal AF; 68% first PVI) underwent post-procedural oesophageal endoscopy and were included in further analyses. Median procedure time was 82.8 ± 24.4 min with ablation times of 16.1 ± 9.2 min. Thermal oesophageal injury was detected in 58 patients (6%) (n = 29 Category 1 erosion, n = 29 Category 2 ulcerous). One patient developed oesophageal perforation (redo, 4th AF ablation). No patient died. Using multivariable regression models, increased total ablation time [odds ratio (OR) 1.029, P = 0.010] and history of stroke (OR 2.619, P = 0.033) were associated with increased incidence of EDEL after AF ablation, whereas increased body mass index was protective (OR 0.980, P = 0.022). CONCLUSION: Thermal oesophageal lesions occur in 6% of HPSD AF ablations. The risk for development of perforating complications seems to be low. Incidence of atrio-oesophageal fistula (0.1%) is comparable to other reported series about RF ablation approaches.

Safety of very high-power short-duration radiofrequency ablation for pulmonary vein isolation: a two-centre report with emphasis on silent oesophageal injury.

AIMS: Very high-power short-duration (vHPSD) via temperature-controlled ablation (TCA) is a new modality to perform radiofrequency pulmonary vein isolation (PVI), conceivably at the cost of a narrower safety margin towards the oesophagus. In this two-centre trial, we aimed to determine the safety of vHPSD-based PVI with specific emphasis on silent oesophageal injury. METHODS AND RESULTS: Ninety consecutive patients with atrial fibrillation (AF) underwent vHPSD-PVI (90 W, 3-4 s, TCA) using the QDOT MICRO catheter, in conjunction with the nGEN (Bad Neustadt, n = 45) or nMARQ generator (Bruges, n = 45). All patients underwent post-ablation oesophageal endoscopy. Procedural parameters and complications were recorded. A subgroup of 21 patients from Bad Neustadt underwent cerebral magnetic resonance imaging (cMRI) to detect silent cerebral events (SCEs). Mean age was 67 ± 9 years, 59% patients were male, and 66% patients had paroxysmal AF. Pulmonary vein isolation was obtained in all cases after 96 ± 29 min. No steam pop, cardiac tamponade, stroke, or fistula was reported. None of the 90 patients demonstrated oesophageal ulceration (0%). Charring was not observed in the nMARQ cohort (0% vs. 11% in the nGEN group). In 5 out of 21 patients (24%), cMRI demonstrated SCE (exclusively nGEN cohort). CONCLUSION: Temperature-controlled vHPSD catheter ablation allows straightforward PVI without evidence of oesophageal ulcerations or symptomatic complications. Catheter tip charring and silent cerebral lesions when using the nGEN generator have led to further modification.

Multi-national survey on the methods, efficacy, and safety on the post-approval clinical use of pulsed field ablation (MANIFEST-PF).

AIMS: Pulsed field ablation (PFA) is a novel atrial fibrillation (AF) ablation modality that has demonstrated preferential tissue ablation, including no oesophageal damage, in first-in-human clinical trials. In the MANIFEST-PF survey, we investigated the 'real world' performance of the only approved PFA catheter, including acute effectiveness and safety-in particular, rare oesophageal effects and other unforeseen PFA-related complications. METHODS AND RESULTS: This retrospective survey included all 24 clinical centres using the pentaspline PFA catheter after regulatory approval. Institution-level data were obtained on patient characteristics, procedure parameters, acute efficacy, and adverse events. With an average of 73 patients treated per centre (range 7-291), full cohort included 1758 patients: mean age 61.6 years (range 19-92), female 34%, first-time ablation 94%, paroxysmal/persistent AF 58/35%. Most procedures employed deep sedation without intubation (82.1%), and 15.1% were discharged same day. Pulmonary vein isolation (PVI) was successful in 99.9% (range 98.9-100%). Procedure time was 65 min (38-215). There were no oesophageal complications or phrenic nerve injuries persisting past hospital discharge. Major complications (1.6%) were pericardial tamponade (0.97%) and stroke (0.4%); one stroke resulted in death (0.06%). Minor complications (3.9%) were primarily vascular (3.3%), but also included transient phrenic nerve paresis (0.46%), and TIA (0.11%). Rare complications included coronary artery spasm, haemoptysis, and dry cough persistent for 6 weeks (0.06% each). CONCLUSION: In a large cohort of unselected patients, PFA was efficacious for PVI, and expressed a safety profile consistent with preferential tissue ablation. However, the frequency of 'generic' catheter complications (tamponade, stroke) underscores the need for improvement.

Acute and long-term outcomes of VT radiofrequency catheter ablation in patients with versus without an intramural septal substrate.

INTRODUCTION: Aim of this study was to evaluate efficacy and safety of ventricular tachycardia (VT) catheter ablation in patients with structural heart disease (SHD) in relation to the presence of an intramural septal substrate. METHODS: Consecutive patients undergoing VT ablation between January 2019 and October 2020 were included. All patients were stratified based on the presence of relevant septal substrate and freedom from VT recurrences were analyzed. RESULTS: In total, 199 consecutive patients (64.2 ± 13.0 years; 89% male; 55% ischemic cardiomyopathy (ICM)) undergoing VT ablation were included. 129/199 patients (65%) showed significant septal substrate (55/90 patients (61%) with non-ischemic cardiomyopathy (NICM) compared to 74/109 patients (68%) with ICM; p = 0.37). Acute procedural success with elimination of all inducible VTs was achieved in 66/70 patients (94%) without and in 103/129 patients (80%) with a septal substrate (p = 0.007). In the cohort including patients with a clinical FU, 15/60 patients (25%) without a septal substrate and 48/123 patients (39%) with a septal substrate experienced VT recurrence during a FU of 8.1 ± 5.9 months (p = 0.069). CONCLUSION: Presence of septal VT substrate in patients with a structural heart disease or coronary artery disease is common. Acute success of VT catheter ablation was significantly higher and mid-term success tended to be higher in patients without a septal substrate.

Incidence of ablation-induced esophageal injury associated with high-power short duration temperature-controlled pulmonary vein isolation using a specialized open-irrigated ablation catheter: A retrospective single-center study.

INTRODUCTION: To evaluate short-term efficacy and incidence of ablation-induced endoscopically detected esophageal injury in patients undergoing high-power, short-duration (HPSD) pulmonary vein isolation using a novel irrigated radiofrequency ablation catheter and ablation generator setup. METHODS AND RESULTS: Atrial fibrillation (AF) patients, who underwent AF ablation using an irrigated radiofrequency ablation catheter specifically designed for a HPSD ablation approach (50 W, with a target Ablation Index of 350 at posterior wall), received postablation esophageal endoscopy after ablation. In total 45 consecutive patients (67 ± 10 years; 58% male; 42% paroxysmal AF) undergoing AF ablation using a specialized ablation catheter (QDOT) were included in the study. Thirty-one of 45 patients (69%) underwent a first-time pulmonary vein isolation (Group 1, 67 ± 11 years; 55% male; 48% paroxysmal AF). Fourteen patients (31%) underwent a redo AF procedure (Group 2, 66 ± 8 years; 64% male; 29% paroxysmal AF). Patients undergoing first-time pulmonary vein isolation were included in the final analysis. In these patients an endoscopically detected esophageal lesion (EDEL) was detected in 5 of 31 (16%) patients (erosion n = 2, ulcer n = 3). Mean contact force at posterior wall ablation sites was significantly lower in patients with postprocedural EDEL compared with patients without EDEL (11.9 ± 0.8 g vs. 15.6 ± 4.7 g). CONCLUSION: PVI using a specialized high-power ablation catheter in conjunction with a HPSD ablation approach results in a 16% incidence of EDEL in first AF ablation candidates. Future studies evaluating high-power short duration ablation strategies should include esophageal endoscopy to estimate the risk of clinically relevant esophageal complications.

Concomitant epicardial left atrial appendage ligation and left atrial ablation of atrial fibrillation: Safety, feasibility and outcome.

INTRODUCTION: We present initial results of patients undergoing a combined procedure of epicardial LAA ligation in addition to left atrial ablation for AF. METHODS: 9 patients were included for additional use of LARIAT as an individual treatment approach for AF. First an epicardial LAA ligation was performed, in the same procedure left atrial ablations consisting of PVI and additional substrate based modifying ablations were performed. Follow-up at 3 months and 12 months was performed. RESULTS: There was only 1 minor procedural complication (11%) involving epicardial bleeding and 2 late adverse events of pericardial tamponade and stroke. At the final follow-up (median 20 months) 7 patients were in stable sinus rhythm (78%) and 2 pts had reduced AF burden. CONCLUSION: Concomitant epicardial LAA ligation and ablation is feasible in selected patients with a reasonable risk profile. More prospective data are required to validate the safety and efficacy.

Correlation of magnetic resonance imaging and post-ablation endoscopy to detect oesophageal thermal injury in patients after atrial fibrillation ablation: MRI-EDEL-study.

AIMS: To correlate oesophageal magnetic resonance imaging (MRI) abnormalities with ablation-induced oesophageal injury detected in endoscopy. METHODS AND RESULTS: Ablation-naïve patients with atrial fibrillation (AF), who underwent ablation using a contact force sensing irrigated radiofrequency ablation catheter, received a cardiac MRI on the day of ablation, and post-ablation oesophageal endoscopy (OE) 1 day after ablation. Two MRI expert readers recorded presence of abnormal oesophageal tissue signal intensities, defined as increased oesophageal signal in T2-fat-saturated (T2fs), short-tau inversion-recovery (STIR), or late gadolinium enhancement (LGE) sequences. Oesophageal endoscopy was performed by experienced operators. Finally, we correlated the presence of any affection with endoscopically detected oesophageal thermal lesions (EDEL). Among 50 consecutive patients (age 67 ± 7 years, 60% male), who received post-ablation MRI and OE, complete MRI data were available in 44 of 50 (88%) patients. In OE, 7 of 50 (14%) presented with EDEL (Category 1 lesion: erosion n = 3, Category 2 lesion: ulcer n = 4). Among those with EDEL, 6 of 7 (86%) patients presented with increased signal intensities in all three MRI sequences, while only 2 of 37 (5%) showed hyperintensities in all three MRI sequences and negative endoscopy. Correspondingly, sensitivity, specificity, positive predictive value, and negative predictive value (NPV) for MRI (increased signal in T2fs, STIR, and LGE) were 86%, 95%, 75%, and 97%, respectively. CONCLUSION: Increased signal intensity in T2fs, STIR, and LGE represents independent markers of EDEL. In particular, the combination of all three has the highest diagnostic value. Hence, MRI may represent an accurate, non-invasive method to exclude acute oesophageal injury after AF ablation (NPV: 97%).

A collective European experience with left atrial appendage suture ligation using the LARIAT+ device.

AIMS: We report the collective European experience of percutaneous left atrial appendage (LAA) suture ligation using the recent generation LARIAT+ suture delivery device. METHODS AND RESULTS: A total of 141 patients with non-valvular atrial fibrillation and contraindication to oral anticoagulation (OAC), thrombo-embolic events despite OAC or electrical LAA isolation were enrolled at seven European hospitals to undergo LAA ligation. Patients were followed up by clinical visits and transoesophageal echocardiography (TOE) following LAA closure. Left atrial appendage ligation was completed in 138/141 patients (97.8%). Three patients did not undergo attempted deployment of the LARIAT device due to pericardial adhesion after previous epicardial ventricular tachycardia ablation (n = 1), a pericardial access-related complication (n = 1), and multiple posterior LAA lobes (n = 1). Serious 30-day procedural adverse events occurred in 4/141 patients (2.8%). There were two device-related LAA perforations (1.4%) not resulting in any corrective intervention as the LAA was completely sealed with the LARIAT. Minor adverse events occurred in 19 patients (13.5%), including two pericardial effusions due to procedure-related pericarditis requiring pericardiocentesis. Transoesophageal echocardiography was performed after LAA ligation in 103/138 patients (74.6%) after a mean of 181 ± 72 days. Complete LAA closure was documented in 100 patients (97.1%). Two patients (1.8% of patients with follow-up) experienced a transient ischaemic attack at 4 and 7 months follow-up, although there was no leak observed with TOE. There were two deaths during long-term follow-up which were both not device related. CONCLUSION: Initial experience with the LARIAT+ device demonstrates feasibility of LAA exclusion. Further larger prospective studies with longer follow-up are warranted.

Incidence of acute thermal esophageal injury after atrial fibrillation ablation guided by prespecified ablation index.

INTRODUCTION: Ablation index (AI), a novel parameter defining energy application at single ablation lesions, calculated by integration of ablation time, energy, catheter stability, and contact force, has been documented to be associated with effective lesions and higher ablation efficacy. Using a prespecified target AI in addition to acute lesion efficacy may affect local collateral damage like esophageal thermal injury when used for guiding radiofrequency (RF) ablation at the posterior left atrial (LA) wall. METHODS AND RESULTS: Consecutive patients undergoing first AF ablations using AI were included. Ablation energy was reduced to 25 W when ablating at posterior LA wall. Two different individually defined AI target values were used (300 and 350 for posterior wall ablation). Esophageal endoscopy (EE) was performed 1 to 3 days after ablation procedure to document and categorize endoscopically detected esophageal thermal lesion (EDEL). Two-hundred and eleven consecutive patients with postprocedural EE were included. Incidence of EDEL was 14% (29 of 211 patients; mild category 1 lesions in 22 of 29 patients (76%) and severe category 2 lesions (ulcers > 5 mm) in 7 of 29 patients (24% of EDEL group, 3% of total group). Ablation time at posterior LA wall (9.5 vs 9.0 minutes [P = .67]) was comparable in patients with and without EDEL. CONCLUSION: LA posterior wall RF ablation adopting AI ≤350 was associated with 14% esophageal thermal injury including 3% of severe esophageal thermal ulcers. This incidence is comparable to historic control groups with non AI-guided AF ablation.

Association of left atrial low-voltage area and thromboembolic risk in patients with atrial fibrillation.

Aims: Atrial fibrillation (AF) is associated with thromboembolic events. Currently, the CHA2DS2-VASc score is recommended for thromboembolic risk stratification in non-valvular AF patients. However, recent data suggested a potential role of atrial remodelling on thromboembolism. This study aimed to assess the association between left atrial low-voltage area (LVA) and history of clinical manifest as well as subclinical silent cerebral ischaemia (SCI) in AF patients. Methods and results: Two-hundred patients [64 ± 10.5 years, 75 women (37.5%)] with symptomatic paroxysmal (n = 88, 44%) or persistent AF undergoing pulmonary vein isolation (PVI) were prospectively enrolled. Left atrial LVA (bipolar voltage < 0.5mV) was evaluated by intra-procedural mapping (>300 points per patient) during sinus rhythm. Cerebral delayed-enhancement magnetic resonance imaging was performed after PVI for detection of pre-existing procedural-independent SCI. Over all, 17 patients (8.5%) had previous history of stroke. Pre-existing SCIs were detected in 135 patients (67.5%). Patients with previous stroke (4.0 ± 1.5 vs. 2.1 ± 1.3, P < 0.0001) and pre-existing SCI (2.7 ± 1.3 vs. 1.5 ± 1.4, P < 0.0001) had a significantly higher CHA2DS2-VASc score. LVA was significantly larger in patients with previous stroke (12.5 ± 8.5% vs. 3.4 ± 5.4%, P < 0.0001) as well as pre-existing SCI (5.8 ± 6.9% vs. 0.8 ± 1.7%, P < 0.0001). Multivariate regression analysis revealed that LVA was independently associated with the presence of SCI [hazard ratio (HR) per 1% LVA 1.13 (1.06-1.22), P = 0.0003] and history of stroke [HR per 1% LVA 1.36 (1.19-1.60), P < 0.0001] after adjustment of CHA2DS2-VASc score. Conclusion: Left atrial LVA is associated with history of stroke and SCI in patients with non-valvular AF and might improve thromboembolic risk stratification after confirmation of its predictive value in future studies.

Incidence of asymptomatic oesophageal lesions after atrial fibrillation ablation using an oesophageal temperature probe with insulated thermocouples: a comparative controlled study.

AIMS: Oesophageal probes to monitor luminal oesophageal temperature (LET) during atrial fibrillation (AF) catheter ablation have been proposed, but their effects remain unclear. Aim of this study is to evaluate the effects of an oesophageal temperature probe with insulated thermocouples. METHODS AND RESULTS: Patients with symptomatic, drug-refractory paroxysmal or persistent AF who underwent left atrial radiofrequency (RF) catheter ablation were prospectively enrolled. Patients were ablated using a single-tip RF contact force ablation catheter. An intraluminal oesophageal temperature probe was used in Group 1. In Group 2, patients were ablated without LET monitoring. Assessment of asymptomatic endoscopically detected oesophageal lesions (EDEL) was performed by oesophagogastroduodenoscopy (EGD) in all patients. Eighty patients (mean age 63.7 ± 10.7 years; men 56%) with symptomatic, drug-refractory paroxysmal (n = 28; 35%) or persistent AF were included. Group 1 and Group 2 patients (n = 40 in each group) were comparable in regard to baseline characteristics, but RF duration on the posterior wall was significantly shorter in Group 1 patients. Overall, seven patients (8.8%) developed EDEL (four ulcerations, three erythema). The incidence of EDEL in Group 1 and Group 2 patients was comparable (7.5 vs. 10%, P = 1.0). No major adverse events were reported in both groups. CONCLUSION: According to these preliminary results, the use of oesophageal temperature probes with insulated thermocouples seems to be feasible in patients undergoing AF RF catheter ablation. The incidence of post-procedural EDEL when using a cut-off of 39°C is comparable to the incidence of EDEL without using a temperature probe.

Impact of surround flow catheter tip irrigation in contact force ablation on the incidence of asymptomatic oesophageal lesions after atrial fibrillation ablation: a prospective comparative study.

AIMS: Aim of this study was to evaluate the impact of a recently introduced contact force ablation catheter with modified irrigation technology compared with a conventionally irrigated ablation catheter on the incidence of endoscopically detected oesophageal lesions (EDEL). METHODS AND RESULTS: Patients with symptomatic, drug-refractory paroxysmal or persistent atrial fibrillation (AF) who underwent left atrial radiofrequency (RF) catheter ablation were prospectively enrolled. Patients were ablated using a single-tip RF contact force ablation catheter with conventional irrigation (Group 1; n = 50) or with a recently introduced intensified 'surround flow' irrigation technology (Group 2; n = 50). Assessment of EDEL was performed by oesophagogastroduodenoscopy in all patients after ablation. A total of 100 patients (mean age 63.6 ± 12.1 years; men 58%) with paroxysmal (n = 41; 41%) or persistent AF were included. Groups 1 and 2 patients were comparable in regard to baseline characteristics and procedural parameters, especially ablation time at posterior left atrial wall. Overall, 13 patients (13%) developed EDEL after AF ablation (8 oesophageal ulcerations, 5 erythema). The incidence of EDEL including oesophageal ulcerations was higher in Group 2 compared with Group 1 patients without statistical significance (18 vs. 8%, P = 0.23). One pericardial tamponade and one access site bleeding occurred in Group 2. No further adverse events were reported in both groups. CONCLUSION: According to these preliminary results, the use of an improved ablation catheter irrigation technology (surround flow) in conjunction with contact force measurement was associated with a higher but not statistically significant probability of oesophageal thermal lesions. Further studies including larger patient cohorts are needed.

Spatial Relationship of Focal Impulses, Rotors and Low Voltage Zones in Patients With Persistent Atrial Fibrillation.

INTRODUCTION: Focal impulses (FI) and rotors are sources associated with the initiation and maintenance of atrial fibrillation (AF). Their ablation results in a lower recurrence rate. The aim of this study was to characterize for the first time the spatial relationship between such sources and atrial low voltage zones (LVZ) representing fibrosis. METHODS: Twenty-five consecutive patients undergoing their first ablation for persistent AF were included. Voltage mapping of both atria was done during AF. Endocardial mapping of FI and rotors (sources) was performed using a basket catheter and displayed using RhythmView(TM) (Topera Inc.) before ablation. Spatial relationship of LVZ and sources was analyzed. RESULTS: LVZs covered 13 ± 12% of right atrial (RA) endocardial surface and 33 ± 25% of left atrial (LA) endocardial surface. The median number of sources was 1 [1-3] in RA and 3 [1-4] in LA. Of LA sources, 18 (30%) were definitely not associated with LVZs or pulmonary vein (PV) antra. Of RA sources, 32 (84%) were remote from LVZ. During ablation of such sources substantial cycle length (CL) prolongation or AF conversion occurred in 11/23 patients (48%). Altogether, 8/11 (73%) of these pertinent sources were located remotely from LVZ and PV antra. CONCLUSIONS: There is a wide discrepancy in distribution of LVZ areas and sites of identified rotors. Site and incidence of FIRM sources appear to be unpredictable with atrial substrate mapping. Further prospective, randomized studies are necessary to elucidate the impact of additional ablation of such sources in patients with persistent or longstanding persistent AF.