| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Circulation. 2004;110:1351-1357.)
© 2004 American Heart Association, Inc.
Original Articles |
From the Hospital of the University of Pennsylvania, Philadelphia, Pa.
Correspondence to Edward P. Gerstenfeld, MD, Hospital of the University of Pennsylvania, 9 Founders Pavilion, 3400 Spruce St, Philadelphia, PA 19104. E-mail edward.gerstenfeld{at}uphs.upenn.edu
Received December 25, 2003; revision received April 20, 2004; accepted April 22, 2004.
| Abstract |
|---|
|
|
|---|
Methods and Results Isolation of arrhythmogenic PVs was initially performed by segmental ostial PV ablation guided by a circular mapping catheter in 341 patients. Patients whose predominant recurrent arrhythmia was a persistent organized tachycardia returned for mapping and ablation. Recurrent organized LA tachycardias (cycle length 253±33 ms, range 213 to 328 ms) occurred in 10 (2.9%) of 341 patients (age 59±9 years, 1 woman). Mapping was consistent with a focal origin in 8 patients and with macroreentry in 1 patient and was unclear in 1 patient owing to degeneration to atrial fibrillation. Focal tachycardias originated from reconnected segments of prior isolated PVs (6 patients), the posterior LA (1 patient), or the superior septum (1 patient). Focal atrial tachycardias were ablated with point lesions that targeted the earliest activation. All reconnected PVs were also reisolated. Reentrant LA flutter occurred around the left PVs in 1 patient. After 6.7±2.3 months of follow-up, 9 (90%) of 10 patients were arrhythmia free (4 of whom were taking antiarrhythmic drug therapy), and one was having recurrent atrial fibrillation.
Conclusions Recurrent organized LA tachycardia after PV isolation is uncommon and typically has a focal origin from reconnected PV ostia. Reisolation of the PV and ablation of non-PV foci are sufficient to treat this proarrhythmia. Linear lesions are only required when a macroreentrant mechanism is present.
Key Words: fibrillation atrium catheter ablation
| Introduction |
|---|
|
|
|---|
| Methods |
|---|
|
|
|---|
Patients with persistent organized left atrial tachycardias after isolation initially underwent electrical cardioversion and frequently discontinuation or change in antiarrhythmic therapy. Those with persistent organized tachycardias more than 6 weeks after ablation that continued despite discontinuation of antiarrhythmic therapy underwent repeat mapping and ablation. All antiarrhythmic agents were discontinued at least 4 days before the procedure. During the repeat ablation session, entrainment was initially performed from the tricuspid valve/inferior vena cava isthmus to exclude a right atrial isthmus dependent atrial flutter. Two transseptal punctures were then performed for placement of a mapping/ablation catheter and circular mapping catheter. A detailed left atrial electroanatomic map was acquired, and entrainment mapping was performed from multiple left and right atrial sites whenever feasible during a stable tachycardia. Ablation was performed with a 4- or 8-mm-tip ablation catheter (Navistar, Biosense Webster, Inc). All patients were prescribed antiarrhythmic therapy for 6 weeks after ablation and followed up in the same manner as after the first procedure.
| Results |
|---|
|
|
|---|
|
Five (1.5%) of the 341 patients developed typical isthmus-dependent right atrial flutter after ablation. Although a right atrial flutter line was not performed as part of the PV isolation procedure, 24% (82 of 341) of patients had undergone right atrial flutter ablations before presenting for PV isolation.
Surface ECG Characteristics
Surface ECG features of the tachycardias were consistent with origin from the superoposterior left atrium (Figures 1 through 4 ![]()
![]()
). The ECG revealed regular atrial activation that was positive in the inferior leads in 8 of 10 patients, although 2 patients had negative components in the inferior leads (Figure 4). The atrial depolarization was always predominantly positive in V1 and positive across the precordium in 8 of 10 patients, with 2 patients having late transitions to a negative atrial depolarization by leads V4 to V5. These features are not consistent with typical isthmus-dependent clockwise or counterclockwise atrial flutter. Because the tachycardia was regular, one could typically visualize the atrial depolarization unobstructed from the prior T wave. Surface ECG features for focal tachycardias were often typical for the PV of origin,15 ie, flat in lead I, lead II
III, negative in aVL, and M-shaped in V1 for left superior PV origin (Figure 1), and positive in lead I, lead II > III, and flat to biphasic in lead aVL, with late-peaking positive wave in lead V1 for right superior PV origin (Figure 2).
|
|
|
|
Intracardiac Features
Activation and/or detailed electroanatomic mapping of the tachycardia revealed a focal origin with concentric spread of activation in 8 patients, of which 6 originated from partially reconnected PV ostia (Figures 1 and 2
), 1 from the posterior LA just outside the left superior PV (Figure 3), and 1 from the superior septum near the limbus of the fossa ovalis. In the 6 patients with earliest activation at the PV ostium, the location of earliest activation was typically at or just inside (<0.5 cm) the PV ostium. This was confirmed by the ablation catheter location relative to the circular Lasso catheter, which was positioned at the PV ostium with intracardiac echocardiography. The tachycardia cycle length was 253±33 ms. Entrainment mapping during stable tachycardia was feasible in 7 patients. The mechanism in 1 patient could not be determined because of degeneration to AF with pacing. Pacing from the tricuspid valve/inferior vena cava isthmus revealed a fused intracardiac activation sequence with a postpacing interval (PPI) >30 ms longer than tachycardia cycle length in all patients. Pacing from the tachycardia focus typically led to an identical intracardiac activation sequence with a tachycardia cycle length equal to the PPI, but often, pacing a short distance away (<1 cm) led to variation in tachycardia cycle length or a short PPI (Figure 5), which made macroreentry around the PVs unlikely.
|
In 1 patient, a detailed activation map was consistent with a macroreentrant circuit around the left-sided (left upper and lower together) PVs (Figure 4). Entrainment mapping from within the tachycardia circuit revealed a tachycardia cycle length equal to the PPI, whereas PPIs were progressively longer with fusion pacing from the right PV, coronary sinus, and right atrium (Figure 6). In addition, the activation time of the tachycardia circuit on the electroanatomic map was equal to the entire tachycardia cycle length.
|
Response to Ablation
In all 8 cases of focal tachycardias, tachycardias abruptly terminated or slowed and terminated during focal application of radiofrequency energy at the site of earliest activation (Figures 1, 2, 3, and 7![]()
![]()
). In 1 patient, the PV tachycardia continued despite dissociation from the rest of the left and right atrium, which suggests that the origin of this tachycardia was inside the PV (Figure 1). Further radiofrequency ablation led to termination of this PV tachycardia. After tachycardia termination, the PV of origin typically exhibited evidence of reconnection, with significant delay in left atrium to PV activation time (Figure 3). These PVs were always reisolated, and in addition, all other reconnected PVs were reisolated. Reisolation of the PVs was also performed in the patient with macroreentrant flutter, to prevent PV triggers from reinitiating tachycardia. In 1 patient early in our experience in whom the mechanism could not be determined because of degeneration to AF with pacing, the PVs were reisolated, and lines were empirically drawn that connected the left inferior PVs to the mitral annulus and connected the superior PVs. No other empiric lines were performed.
|
In the 1 patient who exhibited reentry around the left-sided PVs, linear lesions were placed between the superior PVs, across an isthmus of preserved voltage, which led to abrupt termination of the tachycardia (Figure 4). The right inferior and both left-sided PVs had evidence of segmental reconnection and were reisolated in this patient.
After 6.7±2.3 months (range 2 to 11 months) of follow-up, 9 (90%) of 10 patients were arrhythmia free. Five patients were free of AF or atrial tachycardia without any antiarrhythmic drugs (including the 1 patient in whom the arrhythmia mechanism could not be determined). Four patients are continuing to undergo antiarrhythmic therapy after early (<6 weeks) AF recurrences. One patient is having recurrent AF despite antiarrhythmic therapy.
| Discussion |
|---|
|
|
|---|
We found that persistent organized left atrial tachycardias are uncommon (2.9%) after segmental PV isolation for paroxysmal or persistent AF. The low incidence of these tachycardias suggests that empiric linear lesions are probably not warranted. When left atrial tachycardias do occur, treatment should be tailored to the arrhythmia mechanism. Our experience demonstrates that these tachycardias are typically focal, originating from ostial segments of reconnected PVs. A focal spread of activation seen with electroanatomic mapping, persistence of the tachycardia after PV isolation, changes in tachycardia rate, and markedly different PPIs at adjacent ostial pacing sites favor triggered activity or enhanced automaticity over macroreentry as the mechanism of the majority of tachycardias. Ablation at the site of earliest activation often results in termination of the tachycardia. If the mechanism cannot be determined, reisolation of all reconnected PVs appears to be sufficient in most cases. Linear lesions between anatomic obstacles are only rarely required when a macroreentrant mechanism is demonstrated and should be tailored to interrupt the path of the reentrant circuit.
Prior Work
Prior case reports19,20 from patients without prior ablation have documented focal left atrial tachycardias masquerading as an atypical atrial flutter. Both case reports found that a significant amount of left atrial conduction delay was present, which led to atrial activation time similar to the tachycardia cycle length and therefore surface ECG features similar to a reentrant atypical flutter. Kistler and colleagues21 reported on 27 patients with focal PV tachycardias and no prior ablation. The surface ECG features and focal ostial PV location of these tachycardias were similar to our findings, although only a minority of these tachycardias originated from the right inferior PV (1 of 28 [3.6%] compared with 3 of 10 [30%] in the present study). Villacastin and colleagues11 reported 2 patients with electroanatomic maps interpreted as reentrant left atrial flutter after PV isolation. In the first patient, the tachycardia was terminated with a single radiofrequency application at a site where pacing revealed a tachycardia cycle length equal to the PPI. The second patients tachycardia terminated after 3 radiofrequency applications in the area of early activation. The electroanatomic maps in these cases were interpreted as demonstrating macroreentry; however, one could also interpret them as having focal activation from a PV ostium. Other laboratories912 have described that the majority of regular atrial tachycardias that occur after PV isolation are due to reentry around the mitral annulus or pairs of PVs. These studies did not report whether reisolation of reconnected PVs was also performed. The higher incidence of macroreentrant tachycardias in these series may be due to differences in ablation technique, including complete circumferential rather than segmental PV isolation, empiric isolation of all PVs, or use of 8-mm or irrigated-tip catheters.
In the cases of focal left atrial tachycardias in the present study, there was always significant conduction delay into the PV of origin after sinus rhythm was restored. Creation of a segment of tissue at the PV ostium, uncoupled from the surrounding atrial myocardium after ablation, may provide the substrate for an iatrogenic atrial tachycardia. Focal tachycardias with conduction delay from prior ablation and a circuitous course around prior ablation lesions may be difficult to distinguish from a macroreentrant tachycardia without detailed mapping and pacing from multiple atrial sites.
Bochoeyer and colleagues22 have previously reported surface ECG characteristics of left atrial tachycardias. They reported that left atrial tachycardias were frequently flat in the inferior leads and positive in V1. In the present study, we found a characteristic ECG pattern of positive "flutter" waves in both the inferior leads, V1, and throughout the precordial leads. This is likely due to the focal origin from the superoposterior left atrium for the tachycardias in the present study. With previously reported surface ECG criteria derived from atrial pacemapping,15,23 the morphology of the tachycardia is also frequently suggestive of the PV of origin. Recognition of these features may facilitate ablation.
Study Limitations
Although we characterized 8 of 9 tachycardias as focal in origin, we cannot determine from the present study the difference between triggered activity, abnormal automaticity, or microreentry within the PV as the mechanism of these tachycardias. More extensive pacing or pharmacological maneuvers were not undertaken because of concern that the tachycardias might degenerate to AF.
We performed segmental isolation of arrhythmogenic PVs guided by a circular mapping catheter. It is possible that complete circumferential isolation of all PVs could result in a higher incidence of macroreentrant tachycardias than found in the present series.
Conclusions
Persistent organized left atrial tachycardias after PV isolation for AF are uncommon, occurring in 2.9% of ablated patients and constituting 15% of AF recurrences. Treatment should be tailored to the arrhythmia mechanism. Focal ablation of the tachycardia at the site of earliest activation and reisolation of all reconnected PVs is sufficient in most cases. Linear lesions between anatomic obstacles are required only when a macroreentrant mechanism is demonstrated.
| Acknowledgments |
|---|
| References |
|---|
|
|
|---|
2. Yu WC, Hsu TL, Tai CT, et al. Acquired pulmonary vein stenosis after radiofrequency catheter ablation of paroxysmal atrial fibrillation. J Cardiovasc Electrophysiol. 2001; 12: 887892.[CrossRef][Medline] [Order article via Infotrieve]
3. Pappone C, Rosanio S, Oreta G, et al. Circumferential radiofrequency ablation of pulmonary vein ostia: a new anatomic approach for curing atrial fibrillation. Circulation. 2000; 102: 26192628.
4. Oral H, Scharf C, Chugh A, et al. Catheter ablation for paroxysmal atrial fibrillation: segmental pulmonary vein ostial ablation versus left atrial ablation. Circulation. 2003; 108: 23552360.
5. Haissaguerre M, Jais P, Shah DC, et al. Electrophysiological end point for catheter ablation of atrial fibrillation initiated from multiple pulmonary venous foci. Circulation. 2000; 101: 14091417.
6. Haissaguerre M, Shah DC, Jais P, et al. Electrophysiologic breakthroughs from the left atrium to the pulmonary veins. Circulation. 2000; 102: 24632465.
7. Oral H, Knight BP, Tada H, et al. Pulmonary vein isolation for paroxysmal and persistent atrial fibrillation. Circulation. 2002; 105: 10771081.
8. Marrouche NF, Dresing T, Cole C, et al. Circular mapping and ablation of the pulmonary vein for treatment of atrial fibrillation: impact of different catheter technologies. J Am Coll Cardiol. 2002; 40: 464474.
9. Haissaguerre M, Jais P, Hocini M, et al. Macro-reentrant atrial flutter following ablation of pulmonary veins, tricuspid and mitral isthmuses. Pacing Clin Electrophysiol. 2003; 26: 970. Abstract.
10. Oral H, Knight BP, Morady F. Left atrial flutter after segmental ostial radiofrequency catheter ablation for pulmonary vein isolation. Pacing Clin Electrophysiol. 2003; 26: 14171419.[CrossRef][Medline] [Order article via Infotrieve]
11. Villcastin J, Perez-Castellano N, Moreno J, et al. Left atrial flutter after radiofrequency catheter ablation of focal atrial fibrillation. J Cardiovasc Electrophysiol. 2003; 14: 417421.[CrossRef][Medline] [Order article via Infotrieve]
12. Kanagaratnam L, Tomassoni G, Schweikert R, et al. Empirical pulmonary vein isolation in patients with chronic atrial fibrillation using a three-dimensional nonfluoroscopic mapping system: long-term follow-up. Pacing Clin Electrophysiol. 2001; 24: 17741779.[CrossRef][Medline] [Order article via Infotrieve]
13. Marchlinski FE, Callans DJ, Dixit S, et al. Efficacy and safety of targeted focal ablation versus PV isolation assisted by magnetic electroanatomic mapping. J Cardiovasc Electrophysiol. 2003; 14: 358365.[CrossRef][Medline] [Order article via Infotrieve]
14. Gerstenfeld EP, Dixit S, Callans DC, et al. Utility of exit block for identifying electrical isolation of the pulmonary veins. J Cardiovasc Electrophysiol. 2002; 13: 971979.[CrossRef][Medline] [Order article via Infotrieve]
15. Yamane T, Shah DC, Peng GT, et al. Morphological characteristics of P waves during selective pulmonary vein pacing. J Am Coll Cardiol. 2001; 38: 15051510.
16. Haissaguerre M, Jais P, Shah DC, et al. Spontaneous initiation of atrial fibrillation by ectopic beats originating in the pulmonary veins. N Engl J Med. 1998; 339: 659666.
17. Hocini M, Sanders P, Deisenhofer I, et al. Reverse remodeling of sinus node function after catheter ablation of atrial fibrillation in patients with prolonged sinus pauses. Circulation. 2003; 108: 11721175.
18. Ernst S, Ouyang F, Lober F, et al. Catheter-induced linear lesions in the left atrium in patients with atrial fibrillation: an electroanatomic study. J Am Coll Cardiol. 2003; 42: 12711282.
19. Ouali S, Anselme F, Savoure A, et al. An atypical flutter of focal origin. Pacing Clin Electrophysiol. 2003; 26: 14101412.[CrossRef][Medline] [Order article via Infotrieve]
20. Goya M, Takahashi A, Nuruki N, et al. A peculiar form of atrial tachycardia mimicking atypical atrial flutter. Jpn Circ J. 2000; 64: 886889.[CrossRef][Medline] [Order article via Infotrieve]
21. Kistler PM, Sanders P, Fynn SP, et al. Electrophysiologic and electrocardiographic characteristics of atrial tachycardia originating from the pulmonary veins: acute and long-term outcomes of radiofrequency ablation. Circulation. 2003; 108: 19681975.
22. Bochoeyer A, Yang Y, Cheng J, et al. Surface electrocardiographic characteristics of right and left atrial flutter. Circulation. 2003; 108: 6066.
23. Rajawat YS, Gerstenfeld EP, Patel VV, et al. ECG criteria for localizing the pulmonary vein origin of spontaneous atrial premature complexes: validation using intracardiac recordings. Pacing Clin Electrophysiol. 2004; 27: 182188.[CrossRef][Medline] [Order article via Infotrieve]
This article has been cited by other articles:
![]() |
J. W. Schrickel, L. Lickfett, T. Lewalter, E. Mittman-Braun, S. Selbach, K. Strach, C. P. Nahle, J. O. Schwab, M. Linhart, R. Andrie, et al. Incidence and predictors of silent cerebral embolism during pulmonary vein catheter ablation for atrial fibrillation Europace, January 1, 2010; 12(1): 52 - 57. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-F. Roux, E. Zado, D. J. Callans, F. Garcia, D. Lin, F. E. Marchlinski, R. Bala, S. Dixit, M. Riley, A. M. Russo, et al. Antiarrhythmics After Ablation of Atrial Fibrillation (5A Study) Circulation, September 22, 2009; 120(12): 1036 - 1040. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Y. Reddy, P. Neuzil, S. Themistoclakis, S. B. Danik, A. Bonso, A. Rossillo, A. Raviele, R. Schweikert, S. Ernst, K.-H. Kuck, et al. Visually-Guided Balloon Catheter Ablation of Atrial Fibrillation: Experimental Feasibility and First-in-Human Multicenter Clinical Outcome Circulation, July 7, 2009; 120(1): 12 - 20. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Camm, P. Kirchhof, G. Y.H. Lip, I. Savelieva, and S. Ernst CHAPTER 29 Atrial Fibrillation ESC Textbook of Cardiovascular Medicine, January 1, 2009; 2(1): med-9780199566990-chapter - med-9780199566990-chapter. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Rostock, D. Steven, B. Hoffmann, H. Servatius, I. Drewitz, K. Sydow, K. Mullerleile, R. Ventura, K. Wegscheider, T. Meinertz, et al. Chronic Atrial Fibrillation Is a Biatrial Arrhythmia: Data from Catheter Ablation of Chronic Atrial Fibrillation Aiming Arrhythmia Termination Using a Sequential Ablation Approach Circ Arrhythm Electrophysiol, December 1, 2008; 1(5): 344 - 353. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Knecht, M. Hocini, M. Wright, N. Lellouche, M. D. O'Neill, S. Matsuo, I. Nault, V. S. Chauhan, K. J. Makati, M. Bevilacqua, et al. Left atrial linear lesions are required for successful treatment of persistent atrial fibrillation Eur. Heart J., October 1, 2008; 29(19): 2359 - 2366. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. W. Lim, C. H. Koay, R. McCall, V. A. See, D. L. Ross, and S. P. Thomas Atrial Arrhythmias After Single-Ring Isolation of the Posterior Left Atrium and Pulmonary Veins for Atrial Fibrillation: Mechanisms and Management Circ Arrhythm Electrophysiol, June 1, 2008; 1(2): 120 - 126. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Patel, A. d'Avila, P. Neuzil, S. J. Kim, MSEE, T. Mela, J. P. Singh, J. N. Ruskin, and V. Y. Reddy Atrial Tachycardia After Ablation of Persistent Atrial Fibrillation: Identification of the Critical Isthmus With a Combination of Multielectrode Activation Mapping and Targeted Entrainment Mapping Circ Arrhythm Electrophysiol, April 1, 2008; 1(1): 14 - 22. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Arrantes, F. Gaita, K.-t. Lim, M. Scaglione, P. Jais, M. Hocini, S. Matsuo, S. Knecht, and M. Haissaguerre Atrial fibrillation ablation: evolution of the curative approach Eur. Heart J. Suppl., December 1, 2007; 9(suppl_I): I129 - I135. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Chae, H. Oral, E. Good, S. Dey, A. Wimmer, T. Crawford, D. Wells, J.-F. Sarrazin, N. Chalfoun, M. Kuhne, et al. Atrial Tachycardia After Circumferential Pulmonary Vein Ablation of Atrial Fibrillation: Mechanistic Insights, Results of Catheter Ablation, and Risk Factors for Recurrence J. Am. Coll. Cardiol., October 30, 2007; 50(18): 1781 - 1787. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. P. Daubert Iatrogenic Left Atrial Tachycardias: Where Are We? J. Am. Coll. Cardiol., October 30, 2007; 50(18): 1788 - 1790. [Full Text] [PDF] |
||||
![]() |
M. D. O'Neill, P. Jais, M. Hocini, F. Sacher, G. J. Klein, J. Clementy, and M. Haissaguerre Catheter Ablation for Atrial Fibrillation Circulation, September 25, 2007; 116(13): 1515 - 1523. [Full Text] [PDF] |
||||
![]() |
H. Calkins, J. Brugada, D. L. Packer, R. Cappato, S.-A. Chen, H. J.G. Crijns, R. J. Damiano Jr, D. W. Davies, D. E. Haines, M. Haissaguerre, et al. HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: Recommendations for Personnel, Policy, Procedures and Follow-Up: 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) and the European Cardiac Arrhythmia Society (ECAS); in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), and the Society of Thoracic Surgeons (STS). Endorsed and Approved by the governing bodies of the American College of Cardiology, the American Heart Association, the European Cardiac Arrhythmia Society, the European Heart Rhythm Association, the Society of Thoracic Surgeons, and the Heart Rhythm Society. Europace, June 1, 2007; 9(6): 335 - 379. [Full Text] [PDF] |
||||
![]() |
J. P. Brown, D. E. Krummen, G. K. Feld, and S. M. Narayan Using Electrocardiographic Activation Time and Diastolic Intervals to Separate Focal From Macro-Re-Entrant Atrial Tachycardias J. Am. Coll. Cardiol., May 15, 2007; 49(19): 1965 - 1973. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-Y. Kuo and S.-A. Chen Is Vagal Denervation a Good Alternative or Just Adjunctive to Pulmonary Vein Isolation in Catheter Ablation of Atrial Fibrillation? J. Am. Coll. Cardiol., March 27, 2007; 49(12): 1349 - 1351. [Full Text] [PDF] |
||||
![]() |
M J Earley, D J R Abrams, A D Staniforth, S C Sporton, and R J Schilling Catheter ablation of permanent atrial fibrillation: medium term results Heart, February 1, 2006; 92(2): 233 - 238. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Sanders, M. Hocini, P. Jais, L.-F. Hsu, Y. Takahashi, M. Rotter, C. Scavee, J.-L. Pasquie, F. Sacher, T. Rostock, et al. Characterization of Focal Atrial Tachycardia Using High-Density Mapping J. Am. Coll. Cardiol., December 6, 2005; 46(11): 2088 - 2099. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Essebag, F. Baldessin, M. R. Reynolds, S. McClennen, J. Shah, K. F. Kwaku, P. Zimetbaum, and M. E. Josephson Non-inducibility post-pulmonary vein isolation achieving exit block predicts freedom from atrial fibrillation Eur. Heart J., December 1, 2005; 26(23): 2550 - 2555. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. M. Scheinman and E. Keung The year in clinical electrophysiology J. Am. Coll. Cardiol., March 1, 2005; 45(5): 790 - 795. [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2004 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |