PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of jafibJournal of Atrial Fibrillation
 
J Atr Fibrillation. 2016 December; 9(4): 1490.
Published online 2016 December 31. doi:  10.4022/jafib.1490
PMCID: PMC5673314

Adjunctive Therapies for Catheter Ablation of Non-Paroxysmal Atrial Fibrillation

Abstract

The success rate of pulmonary vein antral isolation (PVAI) for paroxysmal atrial fibrillation (AF) has not been realized for persistent or long-standing AF, collectively termed nonparoxysmal AF. Many investigators have described adjunctive ablation strategies to improve outcomes for catheter ablation in patients with non-paroxysmal AF. In this focused review we aim to describe these therapies and current evidence pertaining to their utilization. At present, left atrial posterior wall (LAPW) ablation, non-pulmonary vein (non-PV) trigger ablation and rotor ablation appear to improve outcomes for patients with non-paroxysmal AF when performed in conjunction with PVAI. Randomized controlled trials are necessary to further elucidate such claims.

Introduction

Atrial Fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice, and is associated with significant morbidity and mortality. In 2010 it was estimated that AF afflicted 5.2 million patients, with 1.2 incident cases diagnosed yearly. These numbers are expected to more than double by the year 2030 to 12.1 million and 2.6 million respectively [1] .

Clinically, AF is classified by the duration of time in the arrhythmia and can be categorized as paroxysmal (self-terminating usually within 48 hours but must last <7 days including spontaneous or electrical cardioversion), persistent (episodes lasting >7 days including pharmacologic or electrical cardioversion after that time), and long standing (continuous AF lasting >1 year at which time a rhythm-control strategy is adopted). These distinctions have been adapted in clinical trials and other forms of research as such classifications have prognostic and therapeutic implications when considering catheter ablation [2] .

Catheter Ablation of Atrial Fibrillation

Although approximately 20-40% of patients with AF are asymptomatic, the vast majority of patients present with symptoms [3]. In general, the approach to asymptomatic patients usually involves a rate-control strategy, whereas symptomatic patients tend to prefer rhythm-control. Radiofrequency (RF) catheter ablation is a successful therapy for eliminating AF and reducing the symptomatic burden in patients with this arrhythmia. Pulmonary Vein Antral Isolation (PVAI) has become the primary ablation strategy for catheter ablation of AF [4]. Success rates vary based on patient characteristics, comorbidities and operator experience, but in general those patients with paroxysmal AF undergoing pulmonary vein isolation have success rates with freedom from atrial arrhythmias approaching 80-85% [5],[6]. Unfortunately, these outcomes have not been realized when PVAI alone is carried out in patients with non-paroxysmal AF where freedom from atrial arrhythmias is closer to 50-60% [7].

Current indications for catheter ablation as proposed by three societal guidelines are outlined in [table 1] [2],[4],[8].These indications continue to evolve over time as catheter ablation has been shown to be more effective in maintaining sinus rhythm as compared to antiarrhythmic drugs (AADs) and the rate of adverse pre, peri and post-procedural events, though not trivial, is comparable to that associated with AADs [2],[9]. Given the disparity in outcomes surrounding paroxysmal and non-paroxysmal AF after PVAI, multiple adjunctive ablation strategies have been described with varying rates of success; the subject of which is discussed below.

Table 1
Indications for catheter ablation for symptomatic non-paroxysmal AF as defined by different societal guidelines.

Adjunctive Modalities for Non-Paroxysmal Atrial Fibrillation

Adjunctive therapies have been developed and studied in an attempt to increase success rates after PVAI in patients with non-paroxysmal AF. These methods, described below, include left atrial posterior wall (LAPW) ablation, non-pulmonary vein trigger ablation of the superior vena cava (SVC), inferior vena cava (IVC), left atrial appendage (LAA), coronary sinus (CS), and vein of marshall (VOM), complex fractionated atrial electrogram (CFAE) ablation, and rotor ablation. It is important to note that these therapies occur in conjunction with PVAI or on repeat catheter ablation.

Left Atrial Posterior Wall Ablation/Isolation

The LAPW has been documented as a potential contributor to the initiation and maintenance of AF [10]. In addition, the structure shares an embryologic cell lineage with the pulmonary veins and thus logically may play a role in the initiation of atrial arrhythmias.

Figure 1.
LAPW ablation

Catheter ablation of the LAPW is accomplished via linear lesions connecting circumferential PV ablation sites, or spot ablations to the entire structure ([Figure 2]). Ablation and proven isolation of the LAPW in conjunction with extended PVAI resulted in superior outcomes (freedom from any atrial arrhythmia) throughout follow up at 1, 2, and 3 years and more than tripled the median time to recurrence in patients with persistent AF [12]. It has also been shown that isolation of the LAPW as compared to PVAI + Linear lesions (Roof and Anterior LA) was associated with a significant (>50%) reduction in the rate of recurrence over the course of 12 month follow up [11]. LAPW ablation/isolation can be accomplished without compromising the pump function of the LA, with few complications and no significant difference in fluoroscopy and procedural times [11],[12].

Figure 2.
Superior Vena Cava Isolation

Superior Vena Cava (SVC)

The SVC shares an embryologic cell lineage with that of the sinus node and thus can represent an arrhythmogenic focus in patients with AF [13]. It also represents the greatest non- PV trigger with an incidence reported anywhere from 6-12% [14]. Although it represents the dominant site of non-PV triggers, early data supporting systematic SVC isolation has not been reproduced for patients with non-paroxysmal AF [15]. The potential benefits of this adjunctive therapy require further examination in larger randomized trials. Phrenic nerve paralysis and injury also poses a limitation on this procedure and precludes up to 15-18% of patients from successful ablation of the SVC [14].

Inferior Vena Cava (IVC)

The IVC has been documented in case-reports as a focal source of ectopic beats resulting in atrial fibrillation. While this trigger is very rare, it does exist and could account for a small proportion of AF recurrences following PVAI. Routine focal ablation of the IVC is not recommended unless triggers are identified [17],[18] .

Left Atrial Appendage (LAA)

The LAA is a known trigger of AF and has been reported in as many as 27% of patients undergoing repeat catheter ablation. In the same patient population, the LAA was found to be the only source of arrhythmia in 8.7%. With complete isolation of the LAA, patients with nonparoxysmal atrial fibrillation had a significant reduction in rate of AF recurrence, while those with focal LAA ablation or no ablation did not [19].

Figure 3.
Epicardial Left Atrial Appendage Ligation

While catheter ablation leading to isolation of LAA has been shown to be effective during repeat ablation, endocardial isolation can be difficult to achieve due to significant anatomic variation in LAA anatomy, and inability to maintain catheter stability. As such epicardial methods to exclude and/or isolate the LAA have been studied. Devices such as the LARIAT© device [SentreHEART, Redwood, CA] and AtriClip® [AtriCure, West Chester, OH have been shown to not only mechanically exclude the LAA but also provide complete electrical isolation. Recently, epicardial LAA exclusion and isolation with the LARIAT© device was found to provide a significant reduction in AF burden at both 3 and 12 month follow up for patients with non-paroxysmal AF [20]. In addition, the strongest predictor of response was known LAA triggers in which the reduction of AF burden was even more pronounced. Complete electrical isolation of the LAA either by catheter ablation or thoracoscopic epicardial exclusion as an adjunct to current ablative therapies seems reasonable, especially in patients with known LAA triggers. A randomized clinical trial (AMAZE AF) is currently being conducted and aims to demonstrate the role of adjunctive exclusion of the LAA.

Coronary Sinus (CS)

The CS has been implicated as a source of triggers contributing to the initiation and maintenance of AF after catheter ablation. In small samples and preliminary data both epicardial and endocardial catheter ablation (complete isolation) in comparison to focal ablation of the coronary sinus resulted in intraprocedural termination of AF in 30% of patients with nonparoxysmal AF [21], [22]. While data regarding CS ablation is less robust than other trigger ablation targets, experts in the field support both epicardial and endocardial ablation of the CS in conjunction with PVAI and other non-PV trigger ablations if spontaneously observed or induced [6].

Vein of Marshall (VOM)

The VOM is the embryologic remnant of the left common and anterior cardinal veins, and has been associated with intrinsic autonomic activity and trigger activity. The VOM was also found to play a role in PV reconnection and recurrence of AF after PVAI [23]. Ethanol infusion into the VOM was effective in disconnecting some of the previously reconnected PVs. In addition, the use of the VOM as a vascular route to the intrinsic cardiac nerves (ICNs) in an effort to modulate autonomic input to the AV node has been investigated [23], [24]. The above mentioned studies are small and larger trials are needed to confirm the role of VOM ablation as an adjunctive therapy for the treatment of AF.

Rotor Ablation

Rotor ablation is founded on the localized source theory in which spiral waves (rotors) and/or focal sources of re-entrant electrical activity can become disorganized and sustain AF. This is in contrast to the multiple wavelet theory in which multiple wandering waves of electrical activity lead to AF. Such rotors and focal sources were found in 97% of cases presenting for ablation in the CONFIRM trial in which focal impulse and rotor modulation (FIRM) was found to successfully slow or terminate AF in 86% of patients (paroxysmal and non-paroxysmal) prior to conventional ablation [25]. In addition, there was a significant reduction in early and late recurrence (median follow up 271 days and 890 day post procedure) in patients undergoing FIRM and conventional ablation as compared to those undergoing only conventional ablation.

There was no difference in procedural time or complications [26]. Patient specific mapping and FIRM ablation is a promising adjunctive therapy and remains to be further validated in randomized controlled trials.

Complex Fractionated Atrial Electrograms (CFAE)

CFAEs are fractionated electrograms that are thought to result from the collision of wavelets and electrical signals traveling in different directions as atrial remodeling occurs. These fractionated electrograms are thought to maintain AF and can be targeted during catheter ablation along with conventional PVAI in an attempt to reduce AF burden. The literature regarding CFAE ablation is conflicting as one meta-analysis reports a significant increase in freedom from all atrial tachyarrhythmias (ATs) in patients with non-paroxysmal but not paroxysmal AF with reported follow up between 10-19 months post procedure depending on the study. Upon repeat analysis in which non-randomized clinical trials were taken out, this effect was no longer statistically significant [27].

In a larger randomized clinical trial with 589 patients, no significant difference in freedom from AF was observed at rigorous 18 month total follow up when comparing PVAI with PVAI + CFAE and PVAI + Linear ablations for patients with non-paroxysmal AF. CFAE ablation also increases procedural time as well as time under fluoroscopy [7]. As a result, it is important to recognize that improved outcomes with CFAE ablation in patients with nonparoxysmal AF have not been uniformly reported and that the rationale of CFAE ablation is not universally accepted.

Conclusion

Isolation of the pulmonary veins is a successful therapy for those patients with paroxysmal but not persistent or long standing (non-paroxysmal) AF. As such, adjunctive ablation strategies to combat recurrence rates in non-paroxysmal AF are the subject of significant research. Although many adjunctive strategies described above lack data from large randomized controlled trials, current evidence seems to support the use of LAPW ablation, rotor ablation, and non-PV trigger ablation of the LAA (from an endocardial or epicardial approach) and to a lesser degree the CS, SVC, IVC and VOM. These therapies are reasonable adjuncts to PVAI in patients with nonparoxysmal atrial fibrillation aimed at long-term freedom from AF recurrence while balancing the risks associated with more technically complex and lengthy procedures. It is important to remember that these procedures are highly dependent on experienced operators in specialized centers.

References

1. Colilla Susan, Crow Ann, Petkun William, Singer Daniel E, Simon Teresa, Liu Xianchen. Estimates of current and future incidence and prevalence of atrial fibrillation in the U.S. adult population. Am. J. Cardiol. 2013 Oct 15;112 (8):1142–7. [PubMed]
2. P Kirchhof, S Benussi, D Kotecha, A Ahlsson, D Atar, B Casadei. guidelines for the management of atrial fibrillation developed in collaboration with EACTS: The task force for the management of atrial fibrillation of the european society of cardiology (ESC)developed with the special contribution of the european heart rhythm association (EHRA) of the ESCEndorsed by the european stroke organisation (ESO). Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups on Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology, 2016;11:0–0.
3. Boriani Giuseppe, Laroche Cecile, Diemberger Igor, Fantecchi Elisa, Popescu Mircea Ioachim, Rasmussen Lars Hvilsted, Sinagra Gianfranco, Petrescu Lucian, Tavazzi Luigi, Maggioni Aldo P, Lip Gregory Y H. Asymptomatic atrial fibrillation: clinical correlates, management, and outcomes in the EORP-AF Pilot General Registry. Am. J. Med. 2015 May;128 (5):509–18.e2. [PubMed]
4. Calkins Hugh, Kuck Karl Heinz, Cappato Riccardo, Brugada Josep, Camm A John, Chen Shih-Ann, Crijns Harry J G, Damiano Ralph J, Davies D Wyn, DiMarco John, Edgerton James, Ellenbogen Kenneth, Ezekowitz Michael D, Haines David E, Haissaguerre Michel, Hindricks Gerhard, Iesaka Yoshito, Jackman Warren, Jalife José, Jais Pierre, Kalman Jonathan, Keane David, Kim Young-Hoon, Kirchhof Paulus, Klein George, Kottkamp Hans, Kumagai Koichiro, Lindsay Bruce D, Mansour Moussa, Marchlinski Francis E, McCarthy Patrick M, Mont J Lluis, Morady Fred, Nademanee Koonlawee, Nakagawa Hiroshi, Natale Andrea, Nattel Stanley, Packer Douglas L, Pappone Carlo, Prystowsky Eric, Raviele Antonio, Reddy Vivek, Ruskin Jeremy N, Shemin Richard J, Tsao Hsuan-Ming, Wilber David. 2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design: a report of the Heart Rhythm Society (HRS) Task Force on Catheter and Surgical Ablation of Atrial Fibrillation. Developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology (ESC) and the European Cardiac Arrhythmia Society (ECAS); and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). Endorsed by the governing bodies of the American College of Cardiology Foundation, the American Heart Association, the European Cardiac Arrhythmia Society, the European Heart Rhythm Association, the Society of Thoracic Surgeons, the Asia Pacific Heart Rhythm Society, and the Heart Rhythm Society. Heart Rhythm. 2012 Apr;9 (4):632–696.e21. [PubMed]
5. Walfridsson H, Walfridsson U, Nielsen J Cosedis, Johannessen A, Raatikainen P, Janzon M, Levin L A, Aronsson M, Hindricks G, Kongstad O, Pehrson S, Englund A, Hartikainen J, Mortensen L S, Hansen P S. Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation: results on health-related quality of life and symptom burden. The MANTRA-PAF trial. Europace. 2015 Feb;17 (2):215–21. [PubMed]
6. Link Mark S, Haïssaguerre Michel, Natale Andrea. Response by Link et al to Letter Regarding Article, "Ablation of Atrial Fibrillation: Patient Selection, Periprocedural Anticoagulation, Techniques, and Preventive Measures After Ablation". Circulation. 2017 Jan 03;135 (1):e3–e4. [PubMed]
7. Verma Atul, Jiang Chen-yang, Betts Timothy R, Chen Jian, Deisenhofer Isabel, Mantovan Roberto, Macle Laurent, Morillo Carlos A, Haverkamp Wilhelm, Weerasooriya Rukshen, Albenque Jean-Paul, Nardi Stefano, Menardi Endrj, Novak Paul, Sanders Prashanthan. Approaches to catheter ablation for persistent atrial fibrillation. N. Engl. J. Med. 2015 May 07;372 (19):1812–22. [PubMed]
8. January Craig T, Wann L Samuel, Alpert Joseph S, Calkins Hugh, Cigarroa Joaquin E, Cleveland Joseph C, Conti Jamie B, Ellinor Patrick T, Ezekowitz Michael D, Field Michael E, Murray Katherine T, Sacco Ralph L, Stevenson William G, Tchou Patrick J, Tracy Cynthia M, Yancy Clyde W. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society. Circulation. 2014 Dec 02;130 (23):2071–104. [PubMed]
9. Mont Lluís, Bisbal Felipe, Hernández-Madrid Antonio, Pérez-Castellano Nicasio, Viñolas Xavier, Arenal Angel, Arribas Fernando, Fernández-Lozano Ignacio, Bodegas Andrés, Cobos Albert, Matía Roberto, Pérez-Villacastín Julián, Guerra José M, Ávila Pablo, López-Gil María, Castro Victor, Arana José Ignacio, Brugada Josep. Catheter ablation vs. antiarrhythmic drug treatment of persistent atrial fibrillation: a multicentre, randomized, controlled trial (SARA study). Eur. Heart J. 2014 Feb;35 (8):501–7. [PMC free article] [PubMed]
10. Lin Wei-Shiang, Tai Ching-Tai, Hsieh Ming-Hsiung, Tsai Chin-Feng, Lin Yung-Kuo, Tsao Hsuan-Ming, Huang Jin-Long, Yu Wen-Chung, Yang Shih-Ping, Ding Yu-An, Chang Mau-Song, Chen Shih-Ann. Catheter ablation of paroxysmal atrial fibrillation initiated by non-pulmonary vein ectopy. Circulation. 2003 Jul 01;107 (25):3176–83. [PubMed]
11. Kim Jin-Seok, Shin Seung Yong, Na Jin Oh, Choi Cheol Ung, Kim Seong Hwan, Kim Jin Won, Kim Eung Ju, Rha Seung-Woon, Park Chang Gyu, Seo Hong Seog, Oh Dong Joo, Hwang Chun, Lim Hong Euy. Does isolation of the left atrial posterior wall improve clinical outcomes after radiofrequency catheter ablation for persistent atrial fibrillation?: A prospective randomized clinical trial. Int. J. Cardiol. 2015 Feb 15;181 ():277–83. [PubMed]
12. Bai Rong, Di Biase Luigi, Mohanty Prasant, Trivedi Chintan, Dello Russo Antonio, Themistoclakis Sakis, Casella Michela, Santarelli Pietro, Fassini Gaetano, Santangeli Pasquale, Mohanty Sanghamitra, Rossillo Antonio, Pelargonio Gemma, Horton Rodney, Sanchez Javier, Gallinghouse Joseph, Burkhardt J David, Ma Chang-Sheng, Tondo Claudio, Natale Andrea. Proven isolation of the pulmonary vein antrum with or without left atrial posterior wall isolation in patients with persistent atrial fibrillation. Heart Rhythm. 2016 Jan;13 (1):132–40. [PubMed]
13. Huang Bien-Hsien, Wu Mei-Han, Tsao Hsuan-Ming, Tai Ching-Tai, Lee Kun-Tai, Lin Yenn-Jiang, Hsieh Ming-Hsiung, Lee Shih-Huang, Chen Yi-Jen, Kuo Jen-Yuan, Chen Shih-Ann. Morphology of the thoracic veins and left atrium in paroxysmal atrial fibrillation initiated by superior caval vein ectopy. J. Cardiovasc. Electrophysiol. 2005 Apr;16 (4):411–7. [PubMed]
14. Arruda Mauricio, Mlcochova Hanka, Prasad Subramanya K, Kilicaslan Fethi, Saliba Walid, Patel Dimpi, Fahmy Tamer, Morales Luis Saenz, Schweikert Robert, Martin David, Burkhardt David, Cummings Jennifer, Bhargava Mandeep, Dresing Thomas, Wazni Oussama, Kanj Mohamed, Natale Andrea. Electrical isolation of the superior vena cava: an adjunctive strategy to pulmonary vein antrum isolation improving the outcome of AF ablation. J. Cardiovasc. Electrophysiol. 2007 Dec;18 (12):1261–6. [PubMed]
15. Corrado Andrea, Bonso Aldo, Madalosso Michela, Rossillo Antonio, Themistoclakis Sakis, Di Biase Luigi, Natale Andrea, Raviele Antonio. Impact of systematic isolation of superior vena cava in addition to pulmonary vein antrum isolation on the outcome of paroxysmal, persistent, and permanent atrial fibrillation ablation: results from a randomized study. J. Cardiovasc. Electrophysiol. 2010 Jan;21 (1):1–5. [PubMed]
16. Chang Hung-Yu, Lo Li-Wei, Lin Yenn-Jiang, Chang Shih-Lin, Hu Yu-Feng, Li Cheng-Hung, Chao Tze-Fan, Chung Fa-Po, Ha Trung Le, Singhal Rahul, Chong Eric, Yin Wei-Hsian, Tsao Hsuan-Ming, Hsieh Ming-Hsiung, Chen Shih-Ann. Long-term outcome of catheter ablation in patients with atrial fibrillation originating from nonpulmonary vein ectopy. J. Cardiovasc. Electrophysiol. 2013 Mar;24 (3):250–8. [PubMed]
17. Mansour Moussa, Ruskin Jeremy, Keane David. Initiation of atrial fibrillation by ectopic beats originating from the ostium of the inferior vena cava. J. Cardiovasc. Electrophysiol. 2002 Dec;13 (12):1292–5. [PubMed]
18. Scavée Christophe, Jaïs Pierre, Weerasooriya Rukshen, Haïssaguerre Michel. The inferior vena cava: an exceptional source of atrial fibrillation. J. Cardiovasc. Electrophysiol. 2003 Jun;14 (6):659–62. [PubMed]
19. Di Biase Luigi, Burkhardt J David, Mohanty Prasant, Sanchez Javier, Mohanty Sanghamitra, Horton Rodney, Gallinghouse G Joseph, Bailey Shane M, Zagrodzky Jason D, Santangeli Pasquale, Hao Steven, Hongo Richard, Beheiry Salwa, Themistoclakis Sakis, Bonso Aldo, Rossillo Antonio, Corrado Andrea, Raviele Antonio, Al-Ahmad Amin, Wang Paul, Cummings Jennifer E, Schweikert Robert A, Pelargonio Gemma, Dello Russo Antonio, Casella Michela, Santarelli Pietro, Lewis William R, Natale Andrea. Left atrial appendage: an underrecognized trigger site of atrial fibrillation. Circulation. 2010 Jul 13;122 (2):109–18. [PubMed]
20. Afzal Muhammad R, Kanmanthareddy Arun, Earnest Matthew, Reddy Madhu, Atkins Donita, Bommana Sudharani, Bartus Krystof, Rasekh Abdi, Han Fred, Badhwar Nitish, Cheng Jie, Dibiase Luigi, Ellis Christopher R, Dawn Buddhadeb, Natale Andrea, Lee Randall J, Lakkireddy Dhanunjaya. Impact of left atrial appendage exclusion using an epicardial ligation system (LARIAT) on atrial fibrillation burden in patients with cardiac implantable electronic devices. Heart Rhythm. 2015 Jan;12 (1):52–9. [PubMed]
21. Haïssaguerre Michel, Hocini Mélèze, Takahashi Yoshihide, O'Neill Mark D, Pernat Andrej, Sanders Prashanthan, Jonsson Anders, Rotter Martin, Sacher Frederic, Rostock Thomas, Matsuo Seiichiro, Arantés Leonardo, Teng Lim Kang, Knecht Sébastien, Bordachar Pierre, Laborderie Julien, Jaïs Pierre, Klein George, Clémenty Jacques. Impact of catheter ablation of the coronary sinus on paroxysmal or persistent atrial fibrillation. J. Cardiovasc. Electrophysiol. 2007 Apr;18 (4):378–86. [PubMed]
22. Marchlinski Francis E, Callans David, Dixit Sanjay, Gerstenfeld Edward P, Rho Robert, Ren Jian-Fang, Zado Erica. Efficacy and safety of targeted focal ablation versus PV isolation assisted by magnetic electroanatomic mapping. J. Cardiovasc. Electrophysiol. 2003 Apr;14 (4):358–65. [PubMed]
23. Dave Amish S, Báez-Escudero José L, Sasaridis Christine, Hong Thomas E, Rami Tapan, Valderrábano Miguel. Role of the vein of Marshall in atrial fibrillation recurrences after catheter ablation: therapeutic effect of ethanol infusion. J. Cardiovasc. Electrophysiol. 2012 Jun;23 (6):583–91. [PubMed]
24. Báez-Escudero José L, Keida Takehiko, Dave Amish S, Okishige Kaoru, Valderrábano Miguel. Ethanol infusion in the vein of Marshall leads to parasympathetic denervation of the human left atrium: implications for atrial fibrillation. J. Am. Coll. Cardiol. 2014 May 13;63 (18):1892–901. [PMC free article] [PubMed]
25. Narayan Sanjiv M, Krummen David E, Shivkumar Kalyanam, Clopton Paul, Rappel Wouter-Jan, Miller John M. Treatment of atrial fibrillation by the ablation of localized sources: CONFIRM (Conventional Ablation for Atrial Fibrillation With or Without Focal Impulse and Rotor Modulation) trial. J. Am. Coll. Cardiol. 2012 Aug 14;60 (7):628–36. [PMC free article] [PubMed]
26. Narayan Sanjiv M, Baykaner Tina, Clopton Paul, Schricker Amir, Lalani Gautam G, Krummen David E, Shivkumar Kalyanam, Miller John M. Ablation of rotor and focal sources reduces late recurrence of atrial fibrillation compared with trigger ablation alone: extended follow-up of the CONFIRM trial (Conventional Ablation for Atrial Fibrillation With or Without Focal Impulse and Rotor Modulation). J. Am. Coll. Cardiol. 2014 May 06;63 (17):1761–8. [PMC free article] [PubMed]
27. Hayward Robert M, Upadhyay Gaurav A, Mela Theofanie, Ellinor Patrick T, Barrett Conor D, Heist E Kevin, Verma Atul, Choudhry Niteesh K, Singh Jagmeet P. Pulmonary vein isolation with complex fractionated atrial electrogram ablation for paroxysmal and nonparoxysmal atrial fibrillation: A meta-analysis. Heart Rhythm. 2011 Jul;8 (7):994–1000. [PMC free article] [PubMed]

Articles from Journal of Atrial Fibrillation are provided here courtesy of CardioFront, LLC