INTRODUCTION:Little is known about very early atrial fibrillation (AF) ablation after first AF detection. METHODS:We evaluated patients with AF ablation <4 months from newly diagnosed paroxysmal AF (NEWPaAF) and newly diagnosed persistent AF (NEWPeAF). We compared the two patient populations and compared ablation outcomes to those undergoing later ablation. RESULTS:Ablation was done <4 months from AF diagnosis in 353 patients (135 = paroxysmal, 218 = persistent). Early ablation outcome was best for NEWPaAF versus NEWPeAF for initial (p = 0.030) but not final (p = 0.102) ablation. Despite recent AF diagnosis in both groups, they were clinically quite different. NEWPaAF patients were younger (64.3 ± 13.0 vs. 67.3 ± 10.9, p = 0.0020), failed fewer drugs (0.39 vs. 0.60, p = 0.007), had smaller LA size (4.12 ± 0.58 vs. 4.48 ± 0.59 cm, p < 0.0001), lower BMI (28.8 ± 5.0 vs. 30.3 ± 6.0, p = 0.016), and less CAD (3.7% vs. 11.5%, p = 0.007), cardiomyopathies (2.2% vs. 22.9%, p = 0.0001), hypertension (46.7% vs. 67.4%, p < 0.0001), diabetes (8.1% vs. 17.4%, p = 0.011) and sleep apnea (20.0% vs. 30.3%, p = 0.031). For NEWPaAF, early ablation AF-free outcome was no better than later ablation (p = 0.314). For NEWPeAF, AF-free outcomes were better for early ablation than later ablation (p < 0.0001). Delaying ablation allowed more strokes/TIAs in both AF types (paroxysmal p = 0.014, persistent p < 0.0001). CONCLUSIONS:Patients presenting for early ablation after newly diagnosed persistent AF have more pre-existing comorbidities and worse initial ablation outcomes than patients with NEWPaAF. For NEWPaAF, there was no advantage to early ablation, as long as the AF remained paroxysmal. For NEWPeAF, early ablation gave better outcomes than later ablation and they should undergo early ablation. For both AF types, waiting was associated with more neurologic events, suggesting all patients should consider earlier ablation.

BACKGROUND Little is known about the very long term durability of atrial fibrillation (AF) ablation.OBJECTIVE The purpose of this study was to evaluate very long term AF ablation outcomes.METHODS We followed 5200 patients undergoing 7145 ablation procedures. We evaluated outcomes after single and multiple abla-tion procedures for paroxysmal (PAF; 33.6%), persistent (PeAF; 56.4%), and long-standing (LsAF; 9.9%) AF. We compared 3 abla-tion eras by initial ablation catheter: early (101 patients) using solid big tip (SBT) catheters (October 2003 to December 2005), in-termediate (2143 patients) using open irrigated tip (OIT) catheters (December 2005 to August 2016), and contemporary (2956 pa-tients) using contact force (CF) catheters (March 2014 to December 2021).RESULTS AF freedom at 5, 10, and 15 years was as follows: initial ablation: PAF 67.8%, 56.3%, 47.6%; PeAF 46.6%, 35.6%, 26.5%; and LsAF 30.4%, 18.0%, 3.4%; final ablation: PAF 80.3%, 72.6%, 62.5%; PeAF 60.1%, 50.2%, 42.5%; and LsAF 43.4%, 32.0%, 20.6%. For PAF and PeAF, CF ablation procedures were better than OIT ablation procedures (P < .0001) and both were better than SBT ablation procedures (P < .001). LsAF had no outcome improve-ment over the eras. The 8-year success rate after final ablation for CF, OIT, and SBT catheter eras was as follows: PAF 79.1%, 71.8%, 60.0%; PeAF 55.9%, 50.7%, 38.0%; and LsAF 42.7%, 36.2%, 31.8%. Highest AF recurrence was in the first 2 years, with a 2-to 15-year recurrence of 2%/yr. Success predictors after initial and final ablation procedures were younger age, smaller left atrium, shorter AF duration, male sex, less persistent AF, lower CHA2DS2- VASc score, fewer drugs failed, and more recent catheter era.CONCLUSION After year 2, there is 2%/yr recurrence rate for all AF types. Ablation success is best in the CF catheter era, intermediate in the OIT era, and worst in the SBT era. Over the ablation eras, out-comes improved for PAF and PeAF but not for LsAF. We should follow patients indefinitely after ablation. We need an understanding of how to better ablate more persistent AF.

Treatment of persistent atrial fibrillation (PeF) remains a procedural challenge with high recurrence rate after catheter ablation. Posterior wall isolation (PWI) has emerged as a potential concomitant treatment strategy for PAF with conflicting outcomes. PWI introduces a left atrial (LA) roof and low posterior line through a series of radiofrequency (RF) applications to achieve entrance and exit block of the LA posterior wall. It remains unclear whether PWI with pulmonary vein isolation (PVI) during initial catheter ablation improves success rate over PVI alone.

Background:Atypical left atrial flutter (AFL) may be macroreentrant or spatially localized. The relationship between the critical isthmus (CI) for localized reentry with sinus rhythm (SR) conduction slowing has not been systematically examined. Objective:To examine the correlation between CI sites for localized AFL (L-AFL) and deceleration zones (DZ) identified by isochronal late activation mapping (ILAM) during baseline rhythm. Methods:Patients with localized AFL who underwent high-density activation mapping of both SR and AFL were retrospectively analyzed. L-AFL was defined as reentry restricted to 2 wall segments of the left atrium. CI was defined by activation mapping and sites of successful termination during ablation. DZ, defined as >3 isochrones within 1 cm radius during baseline rhythm, were correlated to the locations of the CI. Results:Thirty-one consecutive patients that underwent detailed sinus rhythm and AFL high-density activation maps were analyzed at 3 centers. A mean 4060 ± 3275 and 6209 ± 8656 points were collected in ILAM and AFL activation maps, respectively. At least 1 DZ (1.7 ± 0.77) was identified in all patients. ILAM showed 3.27 ± 0.52 isochrones per DZ (168 ± 32 ms), and co-localized to CI sites at a distance of 6.7 ± 3 mm. A total of 34% ± 14% of the AFL cycle length was contained within 0.5 cm of the DZ. Conclusions:In patients with L-AFL, CI co-localized with DZ during baseline rhythm, suggesting that DZ mapping during SR may yield candidate targets for ablation as an adjunct to pulmonary vein isolation to prevent a subtype of AFL.

OBJECTIVES This first-in-human feasibility study was undertaken to translate the novel low-voltage MultiPulse Therapy (MPT) (Cardialen, Inc., Minneapolis, Minnesota), which was previously been shown to be effective in preclinical studies in terminating atrial fibrillation (AF), into clinical use. BACKGROUND Current treatment options for AF, the most common arrhythmia in clinical practice, have limited success. Previous attempts at treating AF by using implantable devices have been limited by the painful nature of high voltage shocks.& nbsp; METHODS Forty-two patients undergoing AF ablation were recruited at 6 investigational centers worldwide. Before ablation, electrode catheters were placed in the coronary sinus, right and/or left atrium, for recording and stimulation. After the induction of AF, MPT, which consists of up to a 3-stage sequence of far-and near -field stimulation pulses varied amplitude, duration, and interpulse timing, was delivered via temporary intracardiac leads. MPT parameters delivery methods were iteratively optimized. RESULTS In the 14 patients from the efficacy phase, MPT terminated 37 of 52 (71%) of AF episodes, with the lowest median energy of 0.36 J (interquartile range [IQR]: 0.14 to 1.21 J) and voltage of 42.5 V (IQR: 25 to 75 V). Overall, 38% AF terminations occurred within 2 seconds of MPT delivery (p < 0.0001). Shorter time between AF induction and predicted success of MPT in terminating AF (p < 0.001).& nbsp; & nbsp;CONCLUSIONS MPT effectively terminated AF at voltages and energies known to be well tolerated or painless in some patients. Our results support further studies of the concept of implanted devices for early AF conversion to reduce burden, symptoms, and progression. (J Am Coll Cardiol EP 2021;7:988 & ndash;999) (c) 2021 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Background The clinical effectiveness of ablating non-paroxysmal atrial fibrillation (non-PAF) relies on proper patient selection. We developed and validated a scoring system to predict non-PAF ablation outcomes. Methods Data on 416 non-PAF ablations were analysed using binary logistic regression at a London centre. Identified preprocedural variables, which independently predicted freedom from atrial tachyarrhythmia. Twenty-one possible predictive variables and a model with c-statistic 0.751—explained outcome variation in London at mean follow-up 12±3 months. An additive point score (range 0–9) was developed—the FLAME score: female=1; long-lasting persistent atrial fibrillation=1; left atrial diameter in mm: 40 to <45 = 1, 45 to <50 = 2, 50 to <55=3, ≥55 =4; mitral regurgitation (MR) mild to moderate=1; extreme comorbidity=2. Extreme comorbidities include severe MR, moderate mitral stenosis, mitral replacement, hypertrophic cardiomyopathy or congenital heart disease. Results The FLAME score was applied to data (882 non-PAF ablations) at a Californian centre, and predicted the outcome of both single (p<0.0001) and multiple (p<0.0001) procedures. For first ablation (follow-up 2.1 years (median, IQR 1.0–4.1)), FLAME score: 0–1 predicts 62% success, 2–4 44% and ≥5 29% (Ptrend <0.0001). After the final ablation (mean procedures: 1.4±0.6, follow-up 1.8 years (median, IQR 0.8–3.6)), FLAME score: 0–1 predicts 81% success, 2–4 65% and ≥5 44% (Ptrend <0.0001). Conclusions FLAME score is easily calculated, derived in London, and predicted single and multiple procedural outcomes for non-PAF ablations in California. In patients with a high score, even multiple procedures are usually ineffective.

This manuscript reviews the literature for all in silico, ex vivo, in vitro, in vivo and clinical studies of high-power short-duration (HPSD) radiofrequency (RF) ablations. It reviews the biophysics of RF energy delivery applicable to HPSD and the use of surrogate endpoints to guide the duration of HPSD ablations. In silico modeling shows that a variety of settings in power, contact force and RF duration can result in the same surrogate endpoint value of ablation index and several HPSD combinations produce lesion volumes similar to a low-power long-duration (LPLD) RF application. HPSD lesions are broader with more endocardial effect and are slightly shallower but still transmural. The first 10 s of RF application is most important for lesion formation with diminishing effect beyond 20 s. The ideal contact force is 10-20 g with only a small effect beyond 30 g. In vitro and in vivo models confirm that HPSD makes transmural lesions that are often broader and shallower, and with proper settings, result in fewer steam pops than LPLD. One randomized trial shows better outcomes with HPSD and validates lesion size index as a surrogate endpoint. Clinical studies of HPSD using comparator groups of LPLD ablations uniformly show shorter procedure times and shorter total RF energy delivery for HPSD. HPSD generally has a higher first pass vein isolation rate and a lower acute vein reconnection rate than LPLD. Although not dramatically different from LPLD, long-term freedom from atrial fibrillation and complication rates seem slightly better with HPSD.

BACKGROUND Little is known about the long-term outcomes and predictors of success of high-power, short-duration (HPSD) contact force (CF) atrial fibrillation (AF) ablations. OBJECTIVE The purpose of this study was to determine long-term freedom from AF and predictors of freedom from AF for 50-W, 5- to 15-second CF ablation. METHODS We examined 4-year outcomes and predictors of freedom from AF after AF ablation for 1250 consecutive patients undergoing HPSD CF ablations. RESULTS Patient demographics were age 66.6 +/- 10.5 years, female 30.9%, left atrial (LA) size 4.26 +/- 0.66 cm, paroxysmal AF 35.7%, persistent AF 56.6%, and longstanding AF 7.7%. Initial ablation times were procedure 114.2 +/- 45.9 minutes, fluoroscopy 15.5 +/- 11.5 minutes, and total radiofrequency 20.6 +/- 7.7 minutes. TactiCath was used in 47.7%, SmartTouch in 52.3%, and posterior wall isolation (PWI) was performed in 34%. Four-year freedom from AF after multiple ablations were paroxysmal AF 87.0%, persistent AF 71.9%, and longstanding AF 64.9%. Single procedure success was 74.9% for TactiCath, 64.7% for SmartTouch (P < .001), and 73.0% for no PWI vs 58.9% for PWI (P < .0001). PWI did not change outcomes for paroxysmal AF but had worse outcomes for nonparoxysmal AF. Multivariate analysis showed 6 independent predictors of worse outcome after initial ablation: older age (P = .014), female gender (P < .0001), persistent AF (P = .0001), larger LA size (P < .001), PWI (P = .049), and use of SmartTouch vs TactiCath catheter (P = .007). Redo ablations were performed in 13.8%, and the outcome was better when more veins had reconnected after the initial ablation and when AF was paroxysmal. CONCLUSION Analysis revealed 6 independent predictors of outcome for HPSD CF. At redo ablations, the outcome was better if more veins had reconnected and could be re-isolated.

Accessory pathway (AP) mapping is currently based on point-by-point mapping and identifying if a local electrogram’s origin is atrial, pathway, or ventricular, which is time-consuming and prone to insufficient mapping. We sought to determine the feasibility of automated and high-density mapping to define AP location using open-window mapping (OWM), which does not rely on defining the electrogram’s origin but simply detects the sharpest local signal at each point. We enrolled 23 consecutive patients undergoing catheter ablation for atrioventricular reentrant tachycardia. High-density mapping was performed using OWM and ablation was performed. The successful site of ablation was determined by the loss of pathway function. OWM was 100% effective at identifying the successful site of ablation (average mapping time 7.3 ± 4.3 min.) Permanent AP elimination was achieved using a mean radiofrequency energy time of 18.5 ± 24.5 s/patient. Transiently successful ablations were 4.0 ± 1.8 mm from permanently successful sites and had lower contact force (5.1 ± 2.5 g vs. 11.7 ± 9.0 g; P = 0.041). Unsuccessful sites had similar contact force to permanently successful sites (12.2 ± 9.2 g vs. 11.7 ± 9.0 g; P = 0.856) but were 6.4 ± 2.0 mm away from successful sites. A novel technique of high-density, automated, and open-window mapping (OWM) effectively localizes APs without the need to differentiate the signal’s site of origin. These findings suggest that OWM can be used to rapidly and successfully map and ablate APs. Both distances from the pathway and contact force were shown to be important for pathway ablation.

Journal of Cardiovascular ElectrophysiologyVolume 32, Issue 2 p. 342-344 EDITORIAL-INVITED The evolution of high-power short-duration atrial fibrillation ablation: “The long slog” Roger A. Winkle MD, Corresponding Author Roger A. Winkle MD rawinkle@aol.com orcid.org/0000-0002-1906-5504 Silicon Valley Cardiology, Sutter Health, Palo Alto Medical Foundation, Palo Alto, California Correspondence Roger A. Winkle, MD, Silicon Valley Cardiology, 1950 University Ave, Suite 160, E Palo Alto, CA 94303. Email: rawinkle@aol.comSearch for more papers by this author Roger A. Winkle MD, Corresponding Author Roger A. Winkle MD rawinkle@aol.com orcid.org/0000-0002-1906-5504 Silicon Valley Cardiology, Sutter Health, Palo Alto Medical Foundation, Palo Alto, California Correspondence Roger A. Winkle, MD, Silicon Valley Cardiology, 1950 University Ave, Suite 160, E Palo Alto, CA 94303. Email: rawinkle@aol.comSearch for more papers by this author First published: 18 July 2020 https://doi.org/10.1111/jce.14680 Disclosures: : Dr. Winkle investor Farapulse, Inc. This paper has been written in correspondence to Update on high-power short-duration ablation for pulmonary vein isolation Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume32, Issue2February 2021Pages 342-344 RelatedInformation

Dr. Winkle is an investor in Farapulse and investigator for Abbott.

There are many obstacles to performing a safe and efficacious atrial fibrillation (AF) ablation. Reliable vascular access, performance of a safe transseptal puncture and avoidance of cardiac perforation, pulmonary vein stenoses and atrial esophageal fistula are important for all AF ablation procedures regardless of the technology and energy sources utilized. This article is protected by copyright. All rights reserved.

To compare findings in patients undergoing atrial fibrillation(AF) and/or atrial flutter(AFl) ablation after failed cut and sew (CS) vs. non-cut and sew (NCS) surgical maze. We compared 10 patients with prior CS to 25 with prior NCS maze undergoing catheter ablation after failed maze. Patient demographics: Age 68.3 ± 8.7 CS vs. 68.2 ± 9.2 NCS(P = 0.977), male 70% CS vs. 72% NCS(P = 1.000), LA size 5.11 ± 0.60 cm CS vs. 4.54 ± 0.92 cm NCS(P = 0.096), sternotomy 100% CS vs. 64% of NCS(P = 0.036). Concomitant heart surgery in 100% CS and 68% NCS(P = 0.073). NCS used radiofrequency 84%, cryoablation 8%, microwave 4%, and ultrasound 4%. All maze operations targeted pulmonary vein (PV) isolation. The maze also targeted the mitral isthmus 100% CS vs. 36% NCS(P = 0.001) and the tricuspid isthmus 90% CS vs. 40% NCS (P = 0.018). Maze failure arrhythmia mechanism was AF 0% CS and 56% NCS (P = 0.0006). Nine CS pts failed for AFl and 1 for RA tachycardia. For NCS pts, 11 failed for AFl. CS isolated 94% of PVs and NCS isolated only 26% of PVs (P < 0.0005). At EPS, clinical and induced arrhythmias were ablated and non-isolated PVs were isolated. After final ablation, arrhythmia-free rates were 60% for CS and 52% for NCS (P = 0.723) after 2.99 ± 2.35 years. After failed surgical maze, CS isolated nearly all PVs and NCS never isolated all PVs and the clinical rhythm was more frequently AF for NCS and AFl for CS. CS remains the surgical gold standard for durable PV isolation.

Journal of Cardiovascular ElectrophysiologyVolume 30, Issue 10 p. 1884-1885 EDITORIAL–INVITED High-power short-duration ablation: Turn up the heat to cool down the esophagus Roger A. Winkle MD, Corresponding Author Roger A. Winkle MD rawinkle@aol.com orcid.org/0000-0002-1906-5504 Silicon Valley Cardiology, Sutter Health - Palo Alto Medical Foundation, East Palo Alto, California Sequoia Hospital, Redwood City, California Correspondence Roger A. Winkle, MD, Silicon Valley Cardiology, 1950 University Avenue, Suite 160, East Palo Alto, CA 94303. Email: rawinkle@aol.comSearch for more papers by this author Roger A. Winkle MD, Corresponding Author Roger A. Winkle MD rawinkle@aol.com orcid.org/0000-0002-1906-5504 Silicon Valley Cardiology, Sutter Health - Palo Alto Medical Foundation, East Palo Alto, California Sequoia Hospital, Redwood City, California Correspondence Roger A. Winkle, MD, Silicon Valley Cardiology, 1950 University Avenue, Suite 160, East Palo Alto, CA 94303. Email: rawinkle@aol.comSearch for more papers by this author First published: 08 August 2019 https://doi.org/10.1111/jce.14108Citations: 4 Disclosures: : None Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume30, Issue10October 2019Pages 1884-1885 RelatedInformation