Carola Gianni

Acute and early outcomes of focal impulse and rotor modulation (FIRM)-guided rotors-only ablation in patients with nonparoxysmal atrial fibrillation

BACKGROUND Focal impulse and rotor modulation (FIRM)-guided ablation targets sites that are thought to sustain atrial fibrillation (AF). OBJECTIVE The purpose of this study was to evaluate the acute and mid-term outcomes of FIRM-guided only ablation in patients with nonparoxysmal AF. METHODS We prospectively enrolled patients with persistent and long-standing persistent (LSP) AF at three centers to undergo FIRM-guided only ablation. We evaluated acute procedural success (defined as AF termination, organization, or ≥10% slowing), safety (incidence of periprocedural complications), and long-term success (single-procedure freedom from atrial tachycardia [AT]/AF off antiarrhythmic drugs [AAD] after a 2-month blanking period). RESULTS Twenty-nine patients with persistent (N = 20) and LSP (N = 9) AF underwent FIRM mapping. Rotors were presents in all patients, with a mean of 4 ± 1.2 per patient (62% were left atrial); 1 focal impulse was identified. All sources were successfully ablated, and overall acute success rate was 41% (0 AF termination, 2 AF slowing, 10 AF organization). There were no major procedure-related adverse events. After a mean 5.7 months of follow-up, single-procedure freedom from AT/AF without AADs was 17%. CONCLUSION In nonparoxysmal AF patients, targeted ablation of FIRM-identified rotors is not effective in obtaining AF termination, organization, or slowing during the procedure. After mid-term follow-up, the strategy of ablating FIRM-identified rotors alone did not prevent recurrence from AT/AF.

Importance of non–pulmonary vein triggers ablation to achieve long-term freedom from paroxysmal atrial fibrillation in patients with low ejection fraction

BACKGROUND Whether ablation of non-pulmonary vein (PV) triggers after pulmonary vein antrum isolation (PVAI) improves the long-term procedure outcome in patients with paroxysmal atrial fibrillation (PAF) and left ventricular systolic dysfunction is unknown. OBJECTIVE We sought to evaluate whether a more extensive ablation procedure improves outcomes at follow-up. METHODS Consecutive patients with PAF refractory to antiarrhythmic drugs presenting for PVAI were prospectively studied. Patients were categorized into 2 groups: patients with left ventricular ejection fraction (LVEF) ≤35% (group I; n = 175) and patients with LVEF ≥50% (group II; n = 545). Patients in group I were further divided according to whether additional ablation of non-PV triggers was performed (group IA; n = 88) or not (group IB; n = 87). Long-term ablation success off antiarrhythmic drugs after a single procedure was analyzed. RESULTS Patients in group I had more non-PV triggers than did patients in group II (69.1% vs 26.6%; P < .001). During a follow-up of 15.8 ± 4.7 months, fewer patients in group I remained free from recurrences than those in group II (53.7% vs 81.7%; P < .001). Long-term ablation success was higher in group IA than in group IB (75.0% vs 32.2%; P < .001) and similar to that in group II (75.0% vs 81.7%; P = .44). In multivariate analysis, LVEF ≤35% (hazard ratio 1.68; P = .003) and non-PV triggers (hazard ratio 3.12; P < .001) were independent predictors of recurrences. CONCLUSION In patients with PAF and left ventricular systolic dysfunction, ablation of non-PV triggers in addition to PVAI significantly improves their long-term procedure outcome.

Pulmonary Vein Antrum Isolation in Patients With Paroxysmal Atrial Fibrillation More Than a Decade of Follow-Up

Background—We report the outcome of pulmonary vein (PV) antrum isolation in paroxysmal atrial fibrillation (AF) patients over more than a decade of follow-up. Methods and Results—A total of 513 paroxysmal AF patients (age 54±11 years, 73% males) undergoing catheter ablation at our institutions were included in this analysis. PV antrum isolation extended to the posterior wall between PVs plus empirical isolation of the superior vena cava was performed in all. Non-PV triggers were targeted during repeat procedure(s). Follow-up was performed quarterly for the first year and every 6 to 9 months thereafter. The outcome of this study was freedom from recurrent AF/atrial tachycardia. At 12 years, single-procedure arrhythmia-free survival was achieved in 58.7% of patients. Overall, the rate of recurrent arrhythmia (AF/atrial tachycardia) was 21% at 1 year, 11% between 1 and 3 years, 4% between 3 and 6 years, and 5.3% between 6 and 12 years. Repeat procedure was performed in 74% of patients. Reconnection in the PV antrum was found in 31% of patients after a single procedure and in no patients after 2 procedures. Non-PV triggers were found and targeted in all patients presenting with recurrent arrhythmia after ≥2 procedures. At 12 years, after multiple procedures, freedom from recurrent AF/atrial tachycardia was achieved in 87%. Conclusions—In patients with paroxysmal AF undergoing extended PV antrum isolation, the rate of late recurrence is lower than what previously reported with segmental or less extensive antral isolation. However, over more than a decade of follow-up, nearly 14% of patients developed recurrence because of new non-PV triggers.

Differential Association of Exercise Intensity With Risk of Atrial Fibrillation in Men and Women: Evidence from a Meta-Analysis

Despite widespread interest and extensive research, the association between different levels of physical activity (PA) and risk of atrial fibrillation (AF) is still not clearly defined. Therefore, we systematically evaluated and summarized the evidences regarding association of different intensity of PA with the risk of AF in this meta‐analysis.

Hybrid Procedure (Endo/Epicardial) versus Standard Manual Ablation in Patients Undergoing Ablation of Longstanding Persistent Atrial Fibrillation: Results from a Single Center

Ablation of longstanding persistent atrial fibrillation (LSPAF) is the most challenging procedure in the treatment of AF, either by surgical or by percutaneous approach.

Use of non-warfarin oral anticoagulants instead of warfarin during left atrial appendage closure with the Watchman device

BACKGROUND In the stroke prevention trials of left atrial appendage closure with the Watchman device (Boston Scientific), a postimplantation antithrombotic regimen of 6 weeks of warfarin was used. OBJECTIVE Given the clinical complexity of warfarin use, the purpose of this study was to study the relative feasibility and safety of using non-warfarin oral anticoagulants (NOACs) instead of warfarin during the peri- and initial postimplantation periods after Watchman implantation. METHODS This was a retrospective multicenter study of consecutive patients undergoing Watchman implantation and receiving peri- and postprocedural NOACs or warfarin. Transesophageal echocardiography or chest computed tomography was performed between 6 weeks and 4 months postimplant to assess for device-related thrombosis. Bleeding and thromboembolic events also were evaluated at the time of follow-up. RESULTS In 5 centers, 214 patients received NOACs (46% apixaban, 46% rivaroxaban, 7% dabigatran, and 1% edoxaban) in either an uninterrupted (82%) or a single-held-dose (16%) fashion. Compared to a control group receiving uninterrupted warfarin (n = 212), the rates of periprocedural complications, including bleeding events, were similar (2.8% vs 2.4%, P = 1). At follow-up, the rates of device-related thrombosis (0.9% vs 0.5%, P = 1), composite of thromboembolism or device-related thrombosis (1.4% vs 0.9%, P = 1), and postprocedure bleeding events (0.5% vs 0.9%, P = .6) also were comparable between the NOAC and warfarin groups. CONCLUSION NOACs proved to be a feasible peri- and postprocedural alternative regimen to warfarin for preventing device-related thrombosis and thromboembolic complications expected early after appendage closure with the Watchman device, without increasing the risk of bleeding.

Ablating the Posterior Heart: Cardioesophageal Fistula Complicating Radiofrequency Ablation in the Coronary Sinus.

Cardioesophageal fistulas (CEFs) are uncommon but life‐threatening complications of radiofrequency (RF) catheter ablation of atrial fibrillation (AF). They are usually, but not exclusively, related to ablation of the left atrial posterior wall. We report a case of a 73‐year‐old man that presented with CEF following RF ablation in the coronary sinus, highlighting the importance of esophageal temperature monitoring whenever ablating in the posterior heart.

Long-Term Outcome of Pulmonary Vein Isolation With and Without Focal Impulse and Rotor Modulation Mapping: Insights From a Meta-Analysis

Background: This meta-analysis systematically evaluated the outcome of pulmonary vein isolation (PVI) with and without focal impulse and rotor modulation (FIRM) ablation in patients with atrial fibrillation. Methods and Results: Extensive literature search was performed for studies reporting outcomes of PVI alone and PVI+FIRM procedures. For PVI alone, only randomized trials conducted in the past 3 years reporting single-procedure off-antiarrhythmic drugs success rate at ≥12-month follow-up were included. In PVI+FIRM group, all published studies reporting single-procedure off-antiarrhythmic drugs success rate with at least 1-year follow-up were identified. Meta-analytic estimates were derived using DerSimonian and Laird random-effects models, and pooled estimates of success rate (95% confidence interval) were computed. Statistical heterogeneity was assessed using Cochran Q test and I2. Study quality was assessed using Newcastle–Ottawa Scale. Fifteen trials were included, 10 with PVI+FIRM (n=511, nonrandomized prospective design), and 5 with PVI-only trials (n=295, randomized trials). All patients in PVI-only trials had 100% nonparoxysmal atrial fibrillation, except 1 study, and no prior ablations. About 24% of PVI+FIRM population had paroxysmal atrial fibrillation. After 15.9±5.5 (median 12) months follow-up, the off-antiarrhythmic drugs pooled success rate was 50% in FIRM+PVI (95% confidence interval, 28%–72%) and 58% in PVI (95% confidence interval, 46%–71%). Difference in effect size between groups was not statistically significant (P=0.21). No significant heterogeneity (total or within group) was observed in this meta-analysis (negative I2 values considered equal to zero). Conclusions: The overall pooled estimate did not show any therapeutic benefit of PVI+FIRM approach over PVI alone, which suggests the need to reevaluate the clinical use of FIRM ablation in atrial fibrillation.

Difference in thermodynamics between two types of esophageal temperature probes: Insights from an experimental study

BACKGROUND Luminal esophageal temperature monitoring is performed with a variety of temperature probes, but little is known about the relationship between the structure of a given probe and its thermodynamic characteristics. OBJECTIVE The purpose of this study was to evaluate the difference in thermodynamics between a 9Fr standard esophageal probe and an 18Fr esophageal stethoscope. METHODS In the experimental setting, each probe was submerged in a constant temperature water bath maintained at 42°C; in the patient setting, we monitored the temperature with both probes at the same time. RESULTS The time constant of the stethoscope was higher than that of the probe (33.5 vs 8.3 s). Compared to the probe, the mean temperature measured by the stethoscope at 10 seconds was significantly lower (22.5°C ± 0.4°C vs 33.5°C ± 0.3°C, P<.0001), whereas the time to reach the peak temperature was significantly longer (132.6 ± 5.9 s vs 38.8 ± 1.0 s, P<.0001). Even in the ablation cases we observed that when the esophageal probe reached a peak temperature of 39.6°C ± 0.3°C, the esophageal stethoscope still displayed a temperature of 37.3°C ± 0.2°C (a mean of 2.39°C ± 0.3°C lower, P<.0001), showing a <0.5°C increase in temperature half of the times. CONCLUSION The 18Fr esophageal stethoscope has a significantly slower time response compared to the 9Fr esophageal probe. In the clinical setting, this might result in a considerable underestimation of the luminal esophageal temperature with potentially fatal consequences.

Association of pretreatment with angiotensin-converting enzyme inhibitors with improvement in ablation outcome in atrial fibrillation patients with low left ventricular ejection fraction.

BACKGROUND Angiotensin-converting enzyme inhibitors (ACEIs) reduce the incidence of atrial fibrillation (AF). OBJECTIVE The purpose of this study was to assess the impact of upstream ACEI therapy on postablation AF recurrence and hospitalization in patients with low left ventricular ejection fraction (LVEF). METHODS Three hundred forty-five consecutive patients undergoing first AF ablation with low LVEF (≤45%) were classified into group 1 (ACEI+, n = 187 [54%], of whom 44 patients [23.5%] had paroxysmal AF [PAF]) or group 2 (ACEI-, n = 158 [46%]; 31 of these 158 patients [19.6%] had PAF). Additionally, 703 consecutive patients with LVEF >45% undergoing first AF ablation were included for a secondary analysis to evaluate the effect of ACEI treatment in normal ejection fraction. In group 1, ACEI therapy started ≥3 months before ablation and continued through follow-up. RESULTS Baseline characteristics were similar except for hypertension, which was significantly more prevalent in ACEI+ (71% vs 51%, P < .001). At 24 ± 7 months of follow-up, 109 nonparoxysmal AF patients in group 1 (76%) and 81 (64%) in group 2 (P = .015) were recurrence free. In multivariate analysis, ACEI therapy was an independent predictor of recurrence (hazard ratio for ACEI-, 1.7, 95% confidence interval 1.1-2.7; P = .026]. However, among PAF patients, ACEI use was not associated with ablation success (80% vs 77% in ACEI+ and ACEI-, respectively; P = .82). In the normal-EF population, the success rates between ACEI+ and ACEI- cohorts were similar (71% vs 74%, P = .31). After the index procedure, 17 patients (9.1%) in the ACEI+ group and 28 (17.7%) in the ACEI- cohort (P= .02) required rehospitalization, for a 49% relative risk reduction (relative risk 0.51, 95% confidence interval 0.29-0.90). CONCLUSION Preablation use of an ACEI is associated with improvement in ablation outcome in patients with nonparoxysmal AF with low LVEF.