Radiofrequency Ablation Of Atrial Flutter Research Articles

Long-term symptomatic benefit after radiofrequency catheter ablation for atrial flutter despite a high incidence of post-procedural atrial fibrillation

Objective — A high proportion of patients develops atrial fibrillation (AF) after ablation for atrial flutter (AFL). Radiofrequency ablation for AFL therefore would only be useful if it leads to a better quality of life despite this high incidence of AF post-ablation.Methods — All patients who underwent AFL ablation in our centre before March 2002 (n = 203) were contacted by letter a median of 2.3 years after their ablation. Sixty-eight percent answered the questionnaire polling the perceived benefits of the procedure.The results were stratified according to the presenting arrhythmia before the ablation: only AFL, predominantly AFL, predominantly AF or class Ic-III AFL.Results — Despite a 60% incidence of AF, 84% considered the procedure to be beneficial during the 1st year and 77% during the 2nd year post-ablation. Patients with predominantly AF before the procedure showed significantly less overall improvement than the 3 other groups (50% and 33% after 1 year and 2 years, p< 0.01) and a smaller reduction in palpitations (50% and 29% after 1 year and 2 years, p< 0.01). The benefit of an ablation was also significantly less in patients who developed AF post-ablation than in patients who were completely arrhythmia free (75% versus 98% 1st year, 58% versus 91% 2nd year; p< 0.01); nevertheless 75% of these patients reported fewer palpitations and 56% tolerated symptoms better than before.Conclusions — Despite a high incidence of AF after AFL ablation, the majority of patients considered the intervention beneficial. Only in patients with predominantly AF before ablation the procedure does not seem beneficial.

3-Dimensional Mapping and Radiofrequency Ablation of Atrial Flutter in a Patient with Interrupted Inferior Vena Cava

The presence of isolated interrupted inferior vena cava (IVC) is very rare. Though the occurrence of typical atrial flutter in this setting has recently been described, the use of 3-dimensional activation mapping to aid the management of such patients has not yet been described. We report the successful ablation of this arrhythmia in a 63-year-old woman using the superior route through the internal jugular vein with the help of a mapping system.

Differential Pacing for Distinguishing Slow Conduction from Complete Conduction Block of the Tricuspid-Inferior Vena Cava Isthmus after Radiofrequency Ablation for Atrial Flutter—Role of Transverse Conduction through the Crista Terminalis

Partial conduction block has been suggested a predictor of recurrence of atrial flutter (AFL). The aim of this study was to assess transverse conduction by the crista terminalis (CT) as a problem in evaluating isthmus block and the usefulness of differential pacing for distinguishing slow conduction (SC) and complete conduction block (CB) across the ablation line. We assessed 14 patients who underwent radiofrequency catheter ablation of the eustachian valve/ridge-tricuspid valve isthmus for typical AFL. Activation patterns along the tricuspid annulus (TA) suggested incomplete CB across the isthmus. In these patients, atrial pacing was performed from the low posteroseptal (PS) and anteroseptal (AS) right atrium (RA) while the ablation catheter was placed at the ablation line where double potentials (DPs) could be recorded. The pattern of activation of the RA free wall was assessed by a 20-pole catheter positioned along the CT during pacing from the coronary sinus (CS) ostium (CSos) and low lateral RA (LLRA). Faster transverse conduction across the CT resulted in simultaneous or earlier activation of the distal halo electrodes than of the more proximal electrodes, suggesting incomplete conduction block across the isthmus. CB (13) and SC (1) were detected as changes in the activation times of the first and second components of DPs (DP1, DP2) during PS RA pacing and AS RA. Similar changes in the activation times DP1 and DP2 during AS RA pacing as compared to PS RA reflected SC through the isthmus, whereas increased DP1 activation time and decreased of DP2 activation time reflected complete conduction block across the isthmus. Transverse conduction across the CT influences the sequence of activation along the TA after isthmus ablation. Differential pacing can distinguish SC from complete conduction block across the ablation line in the isthmus.

160 CENTHER: Radiofrequency ablation of atrial flutter by irrigated tip — middle volume centers — two country experience

160 CENTHER: Radiofrequency ablation of atrial flutter by irrigated tip — middle volume centers — two country experience

160 CENTHER: Radiofrequency ablation of atrial flutter by irrigated tip - middle volume centers - two country experience

160 CENTHER: Radiofrequency ablation of atrial flutter by irrigated tip - middle volume centers - two country experience

Catheter Ablation of Atrial Flutter after Orthotopic Heart Transplantation

Atrial arrhythmias, including atrial flutter, are common in orthotopic heart transplant recipients. However, only a small number of individual case reports describe the electrical circuit and catheter ablation of atrial flutter after heart transplantation. Detailed electrophysiologic evaluation and radiofrequency ablation of atrial flutter were performed in three patients after orthotopic heart transplantation. All cases involved a counterclockwise flutter circuit around the tricuspid annulus. All were successfully ablated at the isthmus between the tricuspid valve and the atrial anastomosis adjacent to the inferior vena cava. Atrial flutter involving a counterclockwise circuit around the tricuspid annulus is common in the heart transplant population. Based on the patients described in this study and other cases reported in the literature, this arrhythmia often is treated successfully by ablation of the isthmus between the tricuspid valve and the atrial anastomosis near the inferior vena cava.

A14-1 USE of irrigated tip catheters in radiofrequency ablation of atrial flutter

A14-1 USE of irrigated tip catheters in radiofrequency ablation of atrial flutter

A23-6 Radiofrequency ablation of atrial flutter in patients with atrial fibrillation treated with propafenone or amiodarone

A23-6 Radiofrequency ablation of atrial flutter in patients with atrial fibrillation treated with propafenone or amiodarone

A23-6 Radiofrequency ablation of atrial flutter in patients with atrial fibrillation treated with propafenone or amiodarone

A23-6 Radiofrequency ablation of atrial flutter in patients with atrial fibrillation treated with propafenone or amiodarone

A14-1 USE of irrigated tip catheters in radiofrequency ablation of atrial flutter

A14-1 USE of irrigated tip catheters in radiofrequency ablation of atrial flutter

Recurrence rate of atrial flutter after initial presentation in patients on drug treatment

Atrial flutter (AFl) recurrence after initial in-patient presentation, cardioversion, and drug treatment is almost universal, often leading to rehospitalization and risk of serious clinical consequences. Radiofrequency ablation of AFl, which has an excellent safety record, should be evaluated as a first-line approach for most patients with AFl.

Long-term outcome of patients after successful radiofrequency ablation for typical atrial flutter.

The aim of the study was to determine the long-term freedom from atrial arrhythmias after radiofrequency ablation of atrial flutter and to determine the factors associated with recurrent arrhythmias. Radiofrequency ablation has emerged as the preferred treatment for recurrent, typical atrial flutter. Although the short-term results after radiofrequency ablation of atrial flutter have been widely reported, there is insufficient data on long-term outcome with respect to the occurrence of atrial arrhythmias in patients after successful ablation. The first 108 patients to undergo successful ablation for typical atrial flutter at the authors' institutions were followed prospectively until the occurrence of typical atrial flutter, atrial fibrillation, atypical atrial flutter, or death. Several prespecified clinical and procedural factors were tested using univariate and multivariate analysis as predictors of arrhythmia recurrence. Patients were followed for a minimum of 3 years and a maximum of 8 years, or until the first arrhythmia recurrence (average duration 17 +/- 17 months). Recurrences of typical atrial flutter were usually observed within the first 6 months (73%, n = 16), with the remainder (27%, n = 6) occurring between 6 months and 2 years, and none were observed later. Freedom from recurrence of typical atrial flutter was 80% at 1 year (95% CIs 72-89%), 73% at 2 years (CIs 63-83%), and 73% at 5 years (CIs 63-83%). By contrast, freedom from occurrence of atrial fibrillation or atypical atrial flutter progressively declined over time; 80% at 1 year (CIs 71-88%), 59% at 2 years (CIs 48-70%), and 33% at 5 years (CIs 19-48%). A history of atrial fibrillation or atypical atrial flutter prior to ablation was associated with an increased risk of occurrence during follow-up (relative risk 3.4, CIs 1.5-8.1, P < 0.05). Freedom from occurrence of any atrial arrhythmia was only 27% at 5 years (CIs 15-40%). After successful ablation of typical atrial flutter, recurrence of typical flutter is relatively uncommon and usually occurs early. However, there is a progressive occurrence of atrial fibrillation and/or atypical flutter during follow-up so that many patients require further antiarrhythmic or additional ablative therapy. Radiofrequency ablation of typical atrial flutter should be considered a palliative procedure for most patients and only one component of the long-term care of the patient with atrial tachyarrhythmias.

Unidirectional conduction block at cavotricuspid isthmus created by radiofrequency catheter ablation in patients with typical atrial flutter.

Although unidirectional conduction block at the cavotricuspid isthmus can be created by radiofrequency ablation for atrial flutter, its underlying mechanism has not been elucidated. Twenty-seven patients (22 men and 5 women; mean age 59 +/- 11 years) who met the following criteria were studied: (1) bidirectional isthmus conduction demonstrable at baseline; (2) at least one linear lesion attempted on the cavotricuspid isthmus with radiofrequency catheter ablation; and (3) conduction times at anterolateral and posteromedial portions of the isthmus measured for both clockwise and counterclockwise directions before the ablation procedure. Unidirectional conduction block was observed before achieving bidirectional block in 9 patients (group I); the remaining 18 patients did not exhibit unidirectional conduction block (group II). All unidirectional conduction blocks were demonstrated in the counterclockwise direction. Anterolateral isthmus conduction time in group I was significantly longer than that in group II in both directions. However, there were no significant differences in posteromedial isthmus conduction time between groups I and II in either direction. Anterolateral isthmus conduction time was significantly longer than posteromedial conduction time in group I but not in group II. There were significant differences in conduction properties at the cavotricuspid isthmus between patients who developed unidirectional conduction block and those who did not. Our results support the notion that anisotropy contributes to the genesis of unidirectional conduction block at the cavotricuspid isthmus during the radiofrequency ablation procedure.

Radiofrequency ablation of atrial flutter combined with closure of atrial septal defect

Radiofrequency ablation of atrial flutter combined with patch closure of an atrial septal defect is described. Radiofrequency energy was delivered in the cavo-tricuspid isthmus and from the inferior margin of the atriotomy down to the septal defect using a temperature-controlled multipolar radiofrequency catheter. In addition, cryolesions were applied to the junction of the ablation scar with the tricuspid annulus and with the ostium of the inferior vena cava. Sinus rhythm was restored and an electrophysiologic study conducted 2 months later confirmed the bidirectional conduction block of the cavo-tricuspid isthmus.

Prospective evaluation of a simplified approach for common atrial flutter radiofrequency ablation with only two catheters Didier Klug, Dominique Lacroix, Bernard d'Hautefeuille, Max Pecheux, St�phane Denneti�re, Claude Kouakam, Christelle Marqui�, Salem Kacet. University of Lille, Lille, France

Prospective evaluation of a simplified approach for common atrial flutter radiofrequency ablation with only two catheters Didier Klug, Dominique Lacroix, Bernard d'Hautefeuille, Max Pecheux, St�phane Denneti�re, Claude Kouakam, Christelle Marqui�, Salem Kacet. University of Lille, Lille, France

Apparent bidirectional conduction block following radiofrequency catheter ablation of typical atrial flutter.

The purpose of this study is to determine the reliability of activation sequence mapping in assessing the presence of bidirectional conduction block (BCB) in typical atrial flutter (AFL) ablation. Radiofrequency ablation (RFA) can cure typical AFL by creating BCB across the right atrial isthmus. Effective conduction block across this region can prevent AFL recurrence, but accurate assessment of isthmus conduction may be flawed. BCB was measured before and after RFA by pacing at multiple rates on both sides of the isthmus during sinus rhythm. Pacing was performed from a low lateral tricuspid annulus site (proximal to the isthmus) and a coronary sinus Os site (distal to the isthmus), while recording simultaneously from 8-10 right atrial sites bordering the isthmus (4-5 free wall sites; 4-5 septal sites) as well as from an isthmus site. After ablation reinduction of atrial flutter was attempted from both sides of the block with rapid atrial pacing after BCB was established in all patients. In some patients lines of conduction block were evident at the isthmus (using the ablation catheter to map). Of 65 patients undergoing RFA of AFL, 59 had typical AFL. In all 59 patients, BCB was demonstrated at all pacing cycle lengths 30 min after RFA applications. In 6 of these 59, AFL was inducible with atrial pacing despite apparent BCB. Further RFA resulted in non inducibility in all 6 patients. In the remaining 53/59 patients, BCB was associated with noninducibility at 30 min. A total of 8 recurrences were seen during a mean 19.3 +/- 8.3 (SD) month follow-up. Apparent BCB as determined by activation sequence mapping outside of the isthmus is an excellent marker, but, as measured, may be a misleading method of assessing the presence or absence of conduction through the isthmus. It is necessary to attempt reinduction of AFL after apparent success. Elimination of typical AFL does not preclude other AFLs.

Simultaneous occurrence of atrial fibrillation and atrial flutter.

Early reports suggested that some patients with "atrial fibrillation/flutter" might have atrial fibrillation in one atrium and atrial flutter in the other. However, more recent conceptions of atrial fibrillation/flutter postulate that the pattern is due to a relatively organized (type I) form of atrial fibrillation. We report the occurrence and ECG manifestations of simultaneous atrial fibrillation and flutter in patients undergoing attempted catheter ablation of atrial flutter. In patients undergoing radiofrequency ablation for atrial flutter, an attempt was made to entrain atrial flutter by pacing in the right atrium. The arrhythmias observed occurred following attempts at entrainment, or spontaneously in one case. Twelve transient episodes of simultaneous atrial fibrillation and flutter were observed in five patients. The atrial fibrillation was localized to all or a portion of one atrium, during which the other atrium maintained atrial flutter. In each case, the surface 12-lead ECG reflected the right atrial activation pattern. No patients had interatrial or intra-atrial conduction block during sinus rhythm, suggesting functional intra-atrial block as a mechanism for simultaneous atrial fibrillation/flutter. In certain patients, the occurrence of transient, simultaneous atrial fibrillation and flutter is possible. In contrast to prior studies in which it was suggested that left atrial or septal activation determines P wave morphology, the results of the present study show that P wave morphology is determined by right atrial activation. Functional interatrial block appears to be a likely mechanism for this phenomenon.

Predictors of success in radiofrequency catheter ablation of atrial flutter.

Radiofrequency catheter ablation of typical atrial flutter at the isthmus between the tricuspid annulus and the inferior vena cava is established. However in selected patients, the creation of a continuous linear lesion at the targeted isthmus requires a lengthened procedure or is not feasible at all and atrial flutter recurrences are common. In a retrospective analysis, we found that an intraoperatively determined distance between the tricuspid annulus and the inferior vena cava of <.2.5 cm is an independent predictor of a lengthened or failed ablation procedure. Additional equipment, e.g., long introducer sheaths, adapted ablation catheter design, or irrigated tip ablation, as well as alternative ablation approaches, e.g., linear lesions between the tricuspid annulus and Eustachian ridge, have been invented in order to increase the acute success rate or decrease fluoroscopy and procedure time. In a prospective study on the effects of various conduction properties at the isthmus between tricuspid annulus and inferior vena cava following radiofrequency ablation of atrial flutter, we showed previously that others than a complete bidirectional conduction block predicts a high recurrence rate of atrial flutter. For determination of transisthmal conduction properties following ablation, established mapping approaches are documentation of double potentials at the ablation line and right atrial activation sequence following posteroseptal and low lateral right atrial pacing. Novel threedimensional mapping systems, i.e., Carto(R) and EnSite(R), may further enhance the accuracy of conventional mapping techniques.

Cavotricuspid Isthmus Mapping to Assess Bidirectional Block During Common Atrial Flutter Radiofrequency Ablation

We sought to compare published methods to an alternative approach ascertaining cavotricuspid isthmus (CTI) block during atrial flutter ablation. In 39 consecutive patients who underwent an atrial flutter ablation procedure, a 24-pole mapping catheter was positioned so that 2 adjacent dipoles were bracketing the targeted CTI line of block (LOB), with proximal dipoles lateral to the LOB and distal dipoles in the coronary sinus. Two pacing sites were lateral (positions A and B) and 2 were septal (positions C and D) to the LOB, with locations A and D closest to the LOB. A resulting CTI block was accepted when 3 criteria were fulfilled: (1) complete reversal of the right atrial depolarization on the 24-pole catheter when pacing in the coronary sinus, (2) conduction delays from A to D greater than from B to D, and (3) conduction delays from D to A greater than from C to A. A successful CTI block was obtained in all patients. Before CTI block was obtained, a progressive CTI conduction delay was observed in 11 patients (28.2%). During the procedure, the 3 criteria defined above were either all present or all absent. This study establishes that reversal of the atrial depolarization sequence up to the LOB is a definitive and mandatory criteria of successful atrial flutter ablation.

Effect of radiofrequency ablation on atrial mechanical function in patients with atrial flutter

Atrial stunning, as assessed by left atrial appendage emptying and increased spontaneous echo contrast, is known to occur following direct-current cardioversion of atrial fibrillation (AF) and atrial flutter (AFl). Little is known on atrial mechanical function and the time course of atrial recovery following radiofrequency ablation of AFl. Fourteen patients undergoing radiofrequency ablation of persistent typical counterclockwise AFl were enrolled. Two-dimensional and pulse Doppler transesophageal echocardiography (TEE) were performed before ablation and immediately following restoration of sinus rhythm. Left atrial spontaneous echo contrast grades, left atrial appendage emptying fractions, and peak left atrial appendage emptying velocities were measured. Transthoracic echocardiography (TTE) was performed immediately after ablation, then repeated after 1 day, 1 week, and 6 weeks to measure peak transmitral velocities and percent atrial contribution to ventricular filling. Left atrial appendage emptying velocities decreased significantly following AFl termination (44 ± 23 cm/s before ablation vs 25 ± 14 cm/s after ablation, p = 0.01). Left atrial appendage emptying fractions also decreased significantly (0.48 ± 0.1 preablation vs 0.34 ± 0.17 postablation, p = 0.02). New spontaneous echo contrast developed in 4 patients (29%) after ablation. Four patients had complete atrial standstill after ablation, and 1 patient developed a new left atrial appendage thrombus. The percent atrial contribution to ventricular filling recovered progressively over 6 weeks with significant improvement in peak transmitral velocities at day 7. Thus, atrial stunning occurs after catheter ablation of AFl and may lead to rapid formation of thrombus in the left atrial appendage. Significant improvement in left atrial function occurs in 7 days.