Abstract Background Pulsed field ablation (PFA) is a relatively new technology for isolation of pulmonary veins in patients with atrial fibrillation (AF). Data addressing reasons for recurrent atrial fibrillation despite primarily successful pulmonary vein isolation (PVI) using PFA are scarce, due to an up to date limited number of patients treated this way. Objective The aim of this study was to analyze electrophysiological characteristics of reconduction and / or left atrial substrate of patients referred to our center for Re-Do procedures for recurrent AF after an initial PVI using PFA. Methods 90 patients (mean age 66±9 years, 69 male (77%)) had been treated in our center from November 2021 to July 2023 with PVI using PFA. 9 (10%) of these patients were referred for Re-Do procedures. These were performed by radiofrequency ablation (RFA) using Carto system including high density mapping and high power / short duration (HPSD) ablation. We analyzed location of PV reconnection and low voltage areas (LVA) in the left atria. Results 7 out of 9 patients (77%) presented with reconnections of pulmonary veins. In one patient a single vein showed reconduction (RSPV), in 5 patients 2 veins were conducting (1x LSPV, 3x LIPV, 1 left sided common os (LCo), 1x RSPV, 3x RIPV). None of the patients showed 3 or 4 reconnected veins. Areas of reconduction in each vein were: LSPV 1x ridge, 1x posterior; LIPV 1x posterior, 1x anterior and posterior; LCo 1x posterior, RSPV 1x anterior, 2x carina, 1x anterior and posterior; RIPV 1x complete, 2x carina. In 7 patients a fibrotic atrial cardiomyopathy (FACM) was diagnosed via high density mapping of LVA’s. In 2 of these patients all 4 pulmonary veins were chronically isolated after the initial PVI. All patients except one (very small anterior LVA) with FACM ≥1 were treated with additional linear or encircling lesions according to the individual extent of the fibrotic areas. 2 patients had no LVA’s detectable. In one of those 2 patients 2 veins had reconnected. The other patient had chronically isolated veins (no proof of dormant conduction with adenosine) and no detectable non-PV-triggers under isoprenaline. Conclusion In the population of patients undergoing PVI using PFA in our center, only 10% had clinically relevant recurrences leading to the necessity of a Re-Do procedure. Most patients (77%) in this setting had reconnections of pulmonary veins. There is a tendency of posterior reconnections of the left pulmonary veins and reconnections of the carina of the right pulmonary veins, but the number of patients is too small to clearly define predilection sites that have to be paid attention to when using PFA. Additionally, left atrial substrate is an important problem in patients with recurrent AF despite primarily successful PVI and has to be considered and thoroughly addressed in Re-Do procedures.Reconnection of LSPV and anterior LVAAblation of RSPV and LSPV (posterior)

Ablation of recurrent atrial fibrillation (AF) is common. Studies indicate that AF recurrence is primarily due to pulmonary vein (PV) re-conduction. This retrospective analysis characterized and evaluated recurrent AF patients using focal impulse and rotor mapping (FIRM) plus PV re-isolation, with follow up at 3, 6, 12, and 24 months after the repeat ablation. Patients (consecutive, n = 100) underwent FIRM-guided ablation followed by conventional PV re-isolation for recurrent AF treatment. All FIRM patients had failed one or more conventional ablation procedures (1.4 ± 0.08) for paroxysmal (14%), persistent (15%), and long-standing persistent (71%) AF. Stable rotors were identified in 97/100 patients: 60% in the right atrium (RA) and 82% in left atrium (LA) (mean 1.5 ± 0.8 and 2.1 ± 1.2 per patient, respectively). No correlation was noted between the previous number of ablations, AF duration, or LA diameter to the number of rotors (R2 = 0.0039, R2 = 0.0017, and R2 = 0.006, respectively). In this limited observation, only 22% of identified rotors were associated with proximity to low voltage areas. The 12- and 24-month arrhythmia free rate was 93% (13/14) and 92% (12/13) for paroxysmal AF, 60% (9/15) and 47% (7/15) for persistent AF, and 70% (48/69) and 64% (43/67) for long-standing persistent AF, respectively, after a single FIRM procedure and re-isolation of the veins. The data show a benefit for FIRM-guided ablation in recurrent AF at 12 months. No correlation was found between rotors and tissue characterization, AF duration, or previous number of ablations, suggesting that rotors may play an independent role in maintaining recurrent AF after prior failed ablation.

Catheter ablation has become the most common therapy in patients with atrial fibrillation (AF). However, despite significant advances in technology and operators’ experience, ablation outcomes remain suboptimal, especially in patients with persistent AF. Focal impulse and rotor modulation (FIRM) represents a new technology for mapping and ablation of patient-specific AF sources. This approach is based on the concept of localized sources, which can be understood as organized rotational waves or focal impulses driving disorganized AF. Several studies, mainly single-center case series, have shown an incremental benefit in long-term outcome when adding FIRM-guided ablation to conventional pulmonary vein isolation (PVI). Therefore, the results of ongoing multicenter randomized trials are needed to support this data.

Peripartum cardiomyopathy (PPCM) is a rare cardiomyopathy characterized by an acute reduction in left ventricular ejection fraction (LVEF). Sudden deaths during the course of PPCM are reported to be elevated, the underlying mechanisms remains unknown. The aim of the present multi-centre study was to evaluate the arrhythmia burden in a multi-centre approach in patients with PPCM using a wearable cardioverter/defibrillator (WCD).

BACKGROUND:There is a lack of procedural and follow-up data on pulmonary vein isolation (PVI) with the second-generation pulmonary vein ablation catheter® (PVAC Gold) in patients with atrial fibrillation (AF). This study provides data on PVI procedures and 1-year follow-up results with PVAC Gold in patients with AF treated in clinical practice.METHODS AND RESULTS:Three hundred and eighty four patients with documented symptomatic paroxysmal (n=198) or persistent (n=186) AF were included in a non-randomized prospectively designed database. Patients were enrolled consecutively at 2 high-volume centers. Procedural as well as 1year follow-up data were systematically analyzed. Average procedure times±standard deviations were 94±23min and 97±23min, respectively, in patients with paroxysmal and persistent AF. Average fluoroscopy times were 14.7±5.4min and 15.2±5.6min and total application times 18.1±5.0min and 18.8±5.2min, respectively, in the 2 patient cohorts. At 12months, 70.7% (70/99) and 61.9% (70/113) of patients with paroxysmal and persistent AF, respectively, were free from AF. Four early complications occurred. In the group with persistent AF, 1 posterior cerebral infarction occurred 2days after the procedure during initiation of anticoagulation. There was no phrenic nerve palsy or esophageal injury associated with the procedures. No thromboembolic events were recorded during follow-up.CONCLUSIONS:In patients with paroxysmal or persistent AF, second generation multi-electrode-phased radiofrequency ablation delivers favorable mid-term PVI success rates with few procedure-related or follow-up complications.

FIRM Ablation Outcomes for Recurrent Nonparoxysmal AFIntroductionA patient‐tailored ablation approach focused on the elimination of both pulmonary vein triggers as well as substrate drivers may result in favorable outcomes in recurrent persistent AF patients.ObjectiveWe evaluated the long‐term outcomes of rotor ablation combined with conventional pulmonary vein isolation (PVI) in patients with recurrent nonparoxysmal AF.MethodsFifty‐eight consecutive patients underwent FIRM‐guided rotor ablation followed by conventional PVI for the treatment of recurrent nonparoxysmal AF. A software algorithm was used to display rotational activity at rotor sites by creating propagation maps from unipolar electrograms recorded using a 64‐electrode basket catheter. These rotor sites were targeted for ablation, followed by conventional PVI.ResultsAll patients had nonparoxysmal AF (83% longstanding persistent) and a previously failed conventional ablation procedure. Stable rotors were identified in all patients (mean of 3.0 ± 1.6 per patient), with 55.2% having right atrial rotors and 96.6% left atrial rotors, respectively. Complications occurred in 5.2% of patients, none related to the FIRM procedure. The median follow‐up was 12 months. At 6 and 12 months of follow‐up, 73.2% and 76.9% of patients remained free from AF/AT, respectively. Excluding 2 patients who underwent a successful redo ablation procedure/electrical cardioversion, at 12 months of follow‐up, 69.2% were free from any AF/AT and 73.1% were free from AF after a single FIRM‐guided ablation procedure.ConclusionA high degree of success was observed in this cohort of primarily longstanding persistent AF patients treated for recurrent AF with FIRM‐guided rotor ablation. Prospective randomized controlled trials are needed.

Focal impulse and Rotor Modulation (FIRM) has been introduced recently as a new approach for ablation of atrial fibrillation (AF).We report a case of FIRM-guided rotor ablation, performed in combination with (re)-pulmonary vein isolation in a patient with recurrent persistent AF and two previous failed conventional ablation procedures.Four rotors could be detected and successfully ablated in this patient, one in the right atrium and three in the left atrium.Notably, the patient experienced a short-term recurrence of AF with spontaneous conversion back to sinus rhythm 11 weeks after the procedure.However, now the patient has been in stable sinus rhythm for 19 months.This case highlights the need to effectively address the specific AF mechanisms, especially in patients with recurrent persistent atrial fibrillation.FIRM-guided rotor ablation seems to be a beneficial option for these patients.

Purpose: Despite significant progress in catheter techniques suboptimal ablation outcomes are observed for patients with atrial fibrillation (AF). This effect is potentially related to the standard approaches of most ablation techniques which mainly focus on anatomic rather than patient specific functional targets. Recently, two new ablation concepts have been introduced which are aimed on patient specific targets. First, stable electrical rotors and focal sources have been demonstrated to sustain AF. Therefore, the ablation of rotors has been associated in first studies with an improved clinical outcome in comparison to conventional ablation. Second, there is increasing evidence that atrial fibrosis can not only be considered as predictor for the ablation outcome but also as a primary disease driving AF. Along this line, atrial fibrosis could be a target for tailored ablation. The aim of this study is to investigate the correlation between rotor acticity and left atrial fibrosis in patients with AF. Methods: Patients that underwent redo procedure for AF using Focal Impulse and Rotor Mapping (FIRM) were analyzed for number and location of rotors and for degree and location of left atrial fibrosis. Left atrial (LA) voltage maps were generated during sinus rhythm after rotor and pulmonary vein isolation. Low voltage was defined as a signal amplitude < 0,5 mV. Fibrosis was categorized as stage 1 (<10% of the LA wall), 2 (≥10%- < 20%), 3 (≥20%- < 30%), and 4 (≥30%). Results: 42 patients (mean age 62 ± 9 years, 31 male) with recurrent AF (37 persistent, 5 paroxysmal) were included. There were 21 patients in stage 1 (50%), 7 in stage 2 (17%), 9 in stage 3 (21%) and 5 in stage 4 (12%). In patients with stage 1 we observed a mean number of RA rotors of 0.6 ± 0,7 (0–2) and LA rotors of 1.4 ± 0.9 (0–4), with stage 2 0.3 ± 0.5 (0–1) and 1.9 ± 0.7 (1–3), with stage 3 1.1 ± 1.1 (0–3) and 2.3 ± 1.0 (1–4) and with stage 4 0.6 ± 0.5 (0–1) and 3.0 ± 1.2 (2–5), respectively. We found significant more LA rotors (2.3 ± 1.0; 1–5) in patients with verification of LA fibrosis (stage 2–4) than in patients without relevant LA fibrosis (p = 0.04). A total of 29 out of 80 LA rotors (36%) in all patients were located in a spacial vicinity of a low voltage area. As expected, the number was higher in patients with LA fibrosis (59%), also depending on the degree of fibrosis (stage 2: 38%, stage 3: 57%, stage 4: 80%). Conclusions: Rotor activity has been identified in patients with and without LA fibrosis. However, more LA rotors have been observed in patients with LA fibrosis. Depending on the degree of fibrosis an increasing number of rotors have been found in spacial vicinity of LA fibrosis areas.

Purpose: Stable electrical rotors and focal sources have been demonstrated to sustain atrial fibrillation (AF). Rotor activity can be demonstrated using a special computational mapping procedure. The aim of this study is to analyze the characteristics of the course of heart rhythm (AF recurrence and restoration of sinus rhythm) after rotor ablation. Methods: Patients who underwent redo procedure for AF (Focal Impulse and Rotor Mapping (FIRM) guided ablation and additional re-pulmonary vein isolation) were analyzed with respect to the time of AF recurrence and the characteristics of restoration of sinus rhythm (SR). Follow-up visits including 96h Holter and/or device interrogation were performed 3, 6 and 12 months after ablation procedure. Results: 44 patients (mean age 63 ± 9 years, 27 male) with recurrent AF (8 paroxysmal, 36 persistent) were included, all of them had undergone 6 month follow-up visit and 26/44 (59%) 12 month follow-up visit so far. We found 52% (23/44) of the patients in stable SR at 3 month, 66% (29/44) at 6 month and 88% (23/26) at 12 month follow-up, respectively. 50% (22/44) of the patients remained in stable SR during the complete follow-up period without any recurrence of AF or atrial tachycardia (AT). 32% (14/44) of the patients were in stable SR at the currently last follow-up even though a recurrence of AF had been observed before at 3 or 6 month follow-up (8 patients with cardioversion to SR between 3 and 6 months after procedure, 6 patients between 6 and 12 months, respectively). The cases of this patient group can be classified as follows: We have observed a spontaneous cardioversion to SR without any intervention for 6/14 (43%) patients (despite persistent AF before). 3/14 (21%) received an additional antiarrhythmic drug therapy (despite ineffectiveness before ablation), 3/14 (21%) underwent an electrical cardioversion and 2/14 (14%) a reablation procedure, respectively. Conclusion: In this single left study we have detected a remarkable increase of success rate over time for patients in stable SR after FIRM-guided ablation from 52% at 3 month follow-up to 88% at 12 month follow-up. We suppose, that there is an additional late effect of rotor ablation, maybe due to a kind of “reverse remodeling” of atrial substrate. Therefore, final ablation outcome should be assessed at the earliest 9 to 12 months after procedure.

Purpose: To provide data on acute and long-term outcomes from pulmonary vein isolation with the pulmonary vein ablation catheter (PVAC) in patients with paroxysmal or persistent atrial fibrillation (AF).Methods: This was a single-center, retrospective, nonrandomized, case control study. Patients with documented symptomatic paroxysmal or persistent AF were treated with PVAC or with pointby-point radiofrequency ablation guided by the NavX T mapping system. All follow-up visits were conducted in our center at 1 month, 3 months, and 6 months, and then at 6-month-intervals. Electrocardiography and 24-hour Holter monitoring were performed at each follow-up visit. The endpoints included procedure times, acute and 24-month outcomes, and complications.Results: Of the 539 patients that were enrolled consecutively, 388 were ablated using PVAC and 151 using radiofrequency ablation. More patients with paroxysmal AF were treated with PVAC than with radiofrequency ablation. Acute success rates were.99% with both methods. Procedure duration and fluoroscopy times were significantly (P, 0.001) shorter with PVAC than with point-by-point ablation. Rates of freedom from AF at all follow-up times available (up to 24 months) were significantly higher after PVAC ablation than with radiofrequency ablation (64.2% versus 48.2% at 24 months). With both ablation strategies, the rates of freedom from AF were higher in patients with paroxysmal AF than for persistent AF. Two posterior cerebral infarcts occurred in the PVAC group within 2 days of the procedure. No phrenic nerve injuries and no esophageal injuries were recorded. Data on embolic lesions were not collected.Conclusion: PVAC ablation achieved higher 24-month rates of AF-free survival than conventional radiofrequency ablation. Procedure and fluoroscopy times were shorter with PVAC, although the differences between groups may have influenced the results.

Introduction: During last years, PVI has developed as a cornerstone therapy for ablation in patients with paroxysmal/persistant AF. With a circular ablation catheter, all pulmonary veins can be isolated with few RF energy applications and without the use of additional mapping systems. The novel technology allowes circular lesions about all 10 electrodes under energy oscillation. Pulmonary vein stenosis (PVST) is an unrequested complication of pulmonary vein isolation (PVI), therefore we reviewed the incidence of PVST after PVI with the PVAC®. Patients and results: 589 patients with paroxysmal or persistent/permanent atrial fibrillation underwent pulmonary vein isolation by using the PVAC®. We isolated a total of 2242 pulmonary veins, in detail 478 left superior PVs, 478 left inferior PVs, 111 left common PVs, 586 right superior PVs, 586 right inferior PVs, and 3 right common PVs. In a subgroup of consecutive 228 patients had CT-scans after 6 months (64-MSCT, slice thickness 0,6 mm, 40 ml saline and 80 ml contrast agent i.v.). As a result we found 1 mild (-50%) pulmonary vein stenosis (see table 1). PV-stenosis after PVAC Summary and conclusion: PVI by using the PVAC®-catheter not only gives equivalent results, but additionally seems to benefit prevention of pulmonary vein stenosis.