Treatment of Recurrent Nonparoxysmal Atrial Fibrillation Using Focal Impulse and Rotor Mapping (FIRM)-Guided Rotor Ablation: Early Recurrence and Long-Term Outcomes.

INTRODUCTION: A 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. OBJECTIVE: We evaluated the long-term outcomes of rotor ablation combined with conventional pulmonary vein isolation (PVI) in patients with recurrent nonparoxysmal AF. METHODS: Fifty-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. RESULTS: All 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. CONCLUSION: A 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.

Retrospective analysis of FIRM-guided ablation in patients with recurrent atrial fibrillation: a single-center study.

BACKGROUND: 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. METHODS AND RESULTS: 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. CONCLUSIONS: 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.

Rotor mapping: black box or very simple? The FIRM approach.

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.

Circumferential pulmonary vein isolation with second-generation multipolar catheter in patients with paroxysmal or persistent atrial fibrillation: Procedural and one-year follow-up results.

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.

Risk for life-threatening arrhythmia in newly diagnosed peripartum cardiomyopathy with low ejection fraction: a German multi-centre analysis.

INTRODUCTION: 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). METHODS AND RESULTS: Forty-nine patients from 16 German centres with newly diagnosed PPCM and LVEF ≤35% receiving a WCD were included in this retrospective analysis. Mean follow-up was 15 ± 10 months. At diagnosis, mean age was 33 ± 5 years, parity was 2.1 ± 1.6, LVEF was 21 ± 7%, NYHA functional class was 3.4 ± 0.7. Mean wear time was 120 ± 106 days, mean wear time per day was 21.4 ± 3.3 h. Six (12%) patients presented eight ventricular tachyarrhythmias during WCD period: five episodes of VF, two sustained ventricular tachycardia (VT) and one non-sustained VT occurred. CONCLUSION: This multicentre study underpins the elevated risk for ventricular tachyarrhythmias in patients with newly diagnosed PPCM and reduced LVEF. A WCD should be considered for 3-6 months in these patients to prevent sudden cardiac death from ventricular tachyarrhythmias.

Ablation of typical atrial flutter using a three-dimensional ultrasound mapping system.

AIMS: The aim of the study was to test the feasibility of the new Realtime Position Management mapping system for ablation of typical atrial flutter. METHODS AND RESULTS: The ultrasound multi-transducer catheters of the RPM Mapping System are placed in the coronary sinus and at the right ventricular apex. Position and movement of the ablation catheter can be depicted on the monitor at any time. Several guiding marks are set in the right atria and thus, define the subsequent lesion lines. A total of 15 patients were treated. In 13 patients complete bi-directional block was established after the ablation. In two patients only significant conduction delay was measured after the end of the procedure. A total of 10.2 +/- 6.3 cooled RF-applications were needed to reach the end-point of the procedure. The total energy was 18.76 +/- 13.23 J. The fluoroscopy time for ablation was 22.2 +/- 8.34 min. During a mean follow-up of 8.4 +/- 3.2 months no recurrence of atrial flutter occurred. One patient developed atypical flutter and another patient had atrial fibrillation. Both patients were treated with antiarrhythmic drugs. There was one ablation related complication, a pericardial effusion. CONCLUSION: The Realtime Position Management system is easy to manage and control. The precision of anatomical linear lesions is improved and fluoroscopic exposure time considerably reduced after learning curve.

[Catheter ablation of atrial fibrillation. Pulmonary vein isolation by using a new multipolar ablation catheter]. / Katheterablation von Vorhofflimmern. Pulmonalvenenisolation mit einem neuen multipolaren Ablationskatheter.

Catheter ablation of atrial fibrillation (AF) is an established therapeutical option, particularly in treatment of paroxysmal atrial fibrillation. This paper presents the results of using the PVAC multi-electrode ablation catheter (PVAC®, Medtronic Ablation Frontiers, Carlsbad, CA, USA). In 253 patients with paroxysmal or persistant AF, 1051 pulmonary veins were isolated, including ablation of 34 left common ostia and 1 right common ostium. Except one vein, all pulmonary veins in all patients were successfully isolated. In 23 patients with documented typical atrial flutter, the right atrial isthmus was additionally ablated within the same procedure. Follow-up (FU) visits were performed after 1, 3, 6 and 12 months with 12-lead-ECG, 24h-Holter-ECG and 4-days-Holter ECG. Mean FU was 11 ± 7 months with 1.1 interventions per patient (24 redo cases). During FU, 122 of 181 patients with paroxysmal AF (69%) and 23 of 40 patients with persistant AF (58%) were in stable sinus rhythm (SR) after ablation. 159 (62.8%) patients wer under antiarrhythmic drugs after ablation, 214 (84.5%) patients with additional ß-blockers. Total procedure time was 71 ± 19 min, and total fluoroscopy time was 16 ± 6 min. In 3 cases (1.2%) procedure-related complications occured. Pulmonary vein isolation by using the PVAC-ablation catheter is a safe and effective method in treatment of paroxysmal and persistant AF.

Primary closed cooled tip ablation of typical atrial flutter in comparison to conventional radiofrequency ablation.

The purpose of this prospective, non-randomized study was to investigate the effectiveness of cooled radiofrequency ablation (cRFA) compared with conventional radio-frequency application (RFA) for ablation of typical atrial flutter (AF). Methods Isthmus ablation was carried out using a system with a circulating fluid path through the ablation tip to control tip temperature in 100 patients with AF. Thirty consecutive AF patients underwent conventional RFA. The number of applications for cRFA was 13.7 +/- 6.9 and for RFA 24.0 +/- 14-5 (P<0.0007) at powers between 35 and 50 W and a tip temperature range of 38-43 degrees C. Ablation duration and fluoroscopy time were 9-9 +/- 4.9 and 22-8 +/- 10.7 min for cRFA, respectively. In contrast, for RFA, ablation duration and fluoroscopy time were 20-6 +/- 14.2 (P<0.0001) and 27.4 +/- 12.7 min, respectively. In 93% of the cooled tip group and in 80% of the control group bi-directional block was confirmed. At 6-months follow-up, recurrence rates were 9 in the cooled-tip group and 7 in the control group, corresponding 10.4% and 25.9%. There were no significant complications. Compared with RFA, cRFA requires lower application numbers. Recurrence rates are low and the overall success rate is high.