Europace Advance Access originally published online on December 24, 2008
Europace 2009 11(2):155-157; doi:10.1093/europace/eun360
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Ablation for Atrial Fibrillation
Routine echocardiography after radiofrequency ablation: to flog a dead horse?
*Department of Cardiology, University Hospital, Petersgraben 4, 4031 Basel, Switzerland
Manuscript submitted 3 October 2008. Accepted after revision 27 November 2008.
* Corresponding author. Tel: +41 61 328 62 22, Fax: +41 61 265 45 98, Email: bschaer{at}uhbs.ch
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Abstract |
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Aims: Radiofrequency ablation (RFA) is frequently used to treat sustained arrhythmias. One major complication is pericardial effusion–tamponade. Therefore, many centres perform echocardiography after interventions, but data on necessity of such routine procedures are scarce.
Methods and results: We included 510 patients with RFA and compared echocardiographic results acquired before and <24 h after intervention. We defined pericardial effusion as ‘small’, if <10 mm in diastole, ‘moderate’ if >10 mm, ‘large’ if >20 mm, or tamponade (>20 mm with haemodynamic compromise). Age was 55 ± 16 years, 40% were females. Thirty-five percentage underwent RFA for atrioventricular nodal re-entrant tachycardia (AVNRT), 28% for atrial flutter, 15% for atrial fibrillation (AF), 12% for Wolff-Parkinson-White (WPW) syndrome, and 10% for different other arrhythmias. In 16 patients (3.2%), small asymptomatic effusions were detected. The only moderate effusion was suspected due to procedure circumstances. Radiofrequency ablation for AF had a higher incidence compared to AVNRT and flutter (P = 0.001 and <0.0001, respectively) or to WPW syndrome (P = 0.06).
Conclusion: Numbers of significant pericardial effusion as detected by routine echocardiography were low (3.6%) and clinically relevant effusions absent. We thus recommend performing echocardiography after RFA only, if effusion is suspected clinically or if RFA was performed for AF, due to the high incidence of effusions with this type of ablation.
Key Words: Echocardiography, Radiofrequency ablation, Supraventricular tachycardia, Pericardial effusion
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Introduction |
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Since 20 years, radiofrequency ablation (RFA) is an established treatment option for patients with different forms of supraventricular tachycardias.1
It confers a high success rate, comprises usually low procedure risks, and offers a good cost-effectiveness.2 Current guidelines3 do not state that echocardiography for exclusion of pericardial effusion, thrombi, or valve damage after RFA is necessary. However, echocardiography has become a standard procedure in certain centres, such as ours. Since the risk of these complications is quite low,4,5 routine echocardiography has to be challenged both from an economic and a cost–benefit point of view. On the other hand, the true incidence of effusion will be underestimated, if echocardiography is performed only in cases with suspected complications. We therefore did a retrospective analysis of consecutive patients who had undergone RFA for any kind of arrhythmias at our institution.
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Methods |
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For this survey, we retrospectively included all 554 patients in whom RFA was performed between July 2004 and December 2006. We had to exclude 7 patients who neither had echocardiography before nor after RFA and 37 patients who did not have it after RFA, thus studying 510 patients.
As a routine procedure, echocardiography was performed before (days to months, not necessarily at our institution) and within 24 h after RFA. The pericardial effusion was measured by the calliper method in two-dimensional mode in a subcostal view, in the parasternal long axis and in the apical four-chamber view. The largest extension was taken as the true one for this study. We defined pericardial effusion according to current guidelines6 as ‘small’, if it was<10 mm, ‘moderate’ if it was at least >10 mm posteriorly, and ‘large’, if it was >20 mm, all in diastole. Pericardial tamponade was defined as being >10 mm with haemodynamic compromise and further signs as summarized in the guidelines. All post-procedure echocardiographies were performed by a fellow and supervised by an experienced senior cardiologist. In cases with dubious findings, the pre-procedure echo, if available, was checked. For the purpose of this study, we further applied the definition of ‘clinically relevant’ (necessitating an intervention) and ‘significant’ (>10 mm) effusions.
Data are presented as mean ± 1 SD. The comparison of the incidence of effusion in different types of arrhythmias was done using a Fisher's t-test. Statistical analysis was realized with the StatView software package version 5.0 (SAS Institute Inc., Cary, NC, USA).
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Results |
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Age of the 510 patients was 55 ± 16 years, with a range of 15–89 years, respectively. Forty percentage were females. Approximately 35% of patients underwent RFA for atrioventricular nodal re-entrant tachycardia (AVNRT), 28% for atrial flutter. Details are given in Table 1.
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A small effusion was present in four patients before as well as after RFA, thus not attributable to the procedure (probably of physiological or post-inflammation origin). In 16 patients (3.2%), a small effusion (never being more than 5 mm in diastole) was detected after RFA. Unfortunately, in six of these patients, no pre-procedure echocardiography was available. Therefore, it remains uncertain if the effusion was really procedure-related. However, using a conservative approach, they were considered to be procedure-related.
There was only one procedure-related effusion of moderate size in a patient with RFA for AVNRT. Due to circumstances (severe pain, bradycardia of <30 per min), a pericarditic response with effusion was already suspected clinically. All other effusions were detected by routine echocardiography without any clinical signs or symptoms. Large or haemodynamically relevant pericardial effusions were not observed in this cohort. During control echocardiography, none of the effusions showed any signs of progression.
Procedure-related valvular or aortic damage was not seen. Of note, pre-procedure echocardiography showed three cases of a prominent rete Chiari, which can impede normal access to the ablation site, and the post-procedure echocardiography in a patient who did not undergo pre-procedure echocardiography revealed a myxoma in the left atrium.
In Table 2, the rates of effusion in the different tachycardia types are depicted. Radiofrequency ablation for paroxysmal atrial fibrillation (AF) had a significantly higher incidence of effusion as compared with either AVNRT or atrial flutter (P-value = 0.001 and <0.0001, respectively) and was almost significant (P-value of 0.06) compared with the Wolff-Parkinson-White (WPW) syndrome. There were no differences between the other tachycardia types.
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The number of additional echocardiographies during short-term and the prolongation of hospitalization in all patients with effusion are shown in Table 3. Of note, signs or symptoms besides in the one patient described in more detail above did not drive either echocardiographies or prolongations of hospitalization.
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Discussion |
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In this large series of patients with RFA, the rate of significant pericardial effusion as detected by routine echocardiography was low (3.6%) and clinically relevant effusions were absent.
There are only limited data4,7 available on the incidence and outcome of pericardial effusion and tamponade after RFA as detected by routine echocardiography. These studies are not recent and thus did not include patients with RFA for paroxysmal or chronic AF. The authors reported an incidence of 2.8% of small effusions, but no tamponade in 387 patients with ablations for AVNRT and WPW.7 This rate is in accordance with the 2.5% of effusions in our corresponding patients. The other study included only 62 patients, 3 of them had small effusions. A larger series of patients was published by Calkins et al.8 in different forms of supraventricular tachycardia, again without AF ablation. The rate of tamponade was 0.6% and that of insignificant effusions 1.5%, but these were not consecutive patients and there is no differentiation into the different arrhythmia types. Advanced age itself is no risk factor for effusion, as has been shown in two trials9,10 in whom patients older than 65 and 75, respectively, were compared with younger ones.
The situation in AF ablation is completely different. Lesions are often transmural, thus leading to irritation and inflammation of the pericardium. The risk of perforation is much higher, due to complications of the trans-septal puncture, manoeuvring of several catheters in the left atrium and the extensive ablation site. Thrombus formation in the left atrium, due to scarring, has to be excluded after RFA. However, the risk of tamponade is only around 1%11,12 and almost always detected immediately due to haemodynamic intolerance. Fortunately, the mortality rate after pericardiocentesis in this situation is extremely low.13 Our reported rate of 13% of non-obstructive effusions is in line with another relatively small study.13
Limitations
This is a single-centre experience, so results may not be generalized, especially not to centres where a more aggressive approach to the ablation procedure exists than might have been the case in our centre. The rate of effusions might also depend on the equipment (catheter size and ablation mode) used. However, a recent study comparing cool-tip catheter ablation to 8 mm catheter ablation did not show a difference in pericardial effusion or tamponade.14
In summary, we recommend to perform echocardiography after RFA only, if effusion or tamponade are suspected clinically or if RFA was performed for AF, due to the high incidence of effusions with this type of ablation.
Conflict of interest: none declared.
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Footnotes |
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Part of the data has been presented at the Congress of the European Society of Cardiology in Vienna on the 2nd of September 2007. 
The first two authors contributed equally to the study.
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References |
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[1] Calkins H. Radiofrequency catheter ablation of supraventricular arrhythmias. Heart (2001) 85:594–600.
[2] Cheng CH, Sanders GD, Hlatky MA, Heidenreich P, McDonald KM, Lee BK, et al. Cost-effectiveness of radiofrequency ablation for supraventricular tachycardia. Ann Intern Med (2000) 133:864–76.
[3] Blomström-Lundqvist C, Scheinman MM, Aliot E, Alpert JS, Calkins H, Camm AJ, et al. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias—executive summary. A report of the American college of cardiology/American heart association task force on practice guidelines and the European society of cardiology committee for practice guidelines (writing committee to develop guidelines for the management of patients with supraventricular arrhythmias) developed in collaboration with NASPE-Heart Rhythm Society. J Am Coll Cardiol (2003) 42:1493–531.
[4] Metzger JT, Cheriex EC, Smeets JL, Vanagt E, Rodriguez LM, Pieters FA, et al. Safety of radiofrequency catheter ablation of accessory atrioventricular pathways. Am Heart J (1994) 127:1533–7.[CrossRef][Medline]
[5] Ng GA, Lau EW, Griffith MJ. A streamlined ‘3-catheter’ approach in the electrophysiological study and radiofrequency ablation of narrow complex tachycardia. J Interv Card Electrophysiol (2002) 7:209–14.[Medline]
[6] Maisch B, Seferovic PM, Ristic AD, Erbel R, Rienmüller R, Adler Y, et al. Guidelines on the diagnosis and management of pericardial disease. Eur Heart J (2004) 25:587–610.
[7] Pires LA, Huang SK, Wagshal AB, Mazzola B, Young PG, Moser S. Clinical utility of routine transthoracic echocardiographic studies after uncomplicated radiofrequency catheter ablation: a prospective multicenter study. The Atakr Investigators Group. Pacing Clin Electrophysiol (1996) 19:1502–7.[CrossRef][Medline]
[8] Calkins H, Yong P, Miller JM, Olshansky B, Carlson M, Saul JP, et al. Catheter ablation of accessory pathways, atrioventricular nodal reentrant tachycardia, and the atrioventricular junction: final results of a prospective, multicenter clinical trial. The Atakr Multicenter Investigators Group. Circulation (1999) 99:262–70.
[9] Haghjoo M, Arya A, Heidari A, Fazelifar AF, Sadr-Ameli MA. Electrophysiologic characteristics and results of radiofrequency catheter ablation in elderly patients with atrioventricular nodal reentrant tachycardia. J Electrocardiol (2007) 40:208–13.[Medline]
[10] Kihel J, Da Costa A, Kihel A, Roméyer-Bouchard C, Thévenin J, Gonthier R, et al. Long-term efficacy and safety of radiofrequency ablation in elderly patients with atrioventricular nodal re-entrant tachycardia. Europace (2006) 8:416–20.
[11] Cappato R, Calkins H, Chen SH, Davies W, Iesaka Y, Kalman J, et al. Worldwide survey on the methods, efficacy and safety of catheter ablation for human atrial fibrillation. Circulation (2005) 111:1100–5.
[12] Pappone C, Oreto G, Rosiano S, Vicedomini G, Tocchi M, Gugliotta F, et al. Atrial electroanatomic remodeling after circumferential radiofrequency pulmonary vein ablation: efficacy of an anatomic approach in a large cohort of patients with atrial fibrillation. Circulation (2001) 104:2539–44.
[13] Ernst S, Schluter M, Ouyang F, Khanedani A, Cappato R, Hebe J, et al. Modification of the substrate for maintenance of idiopathic human atrial fibrillation: efficacy of radiofrequency ablation using nonfluoroscopic catheter guidance. Circulation (1999) 100:2085–92.
[14] Zoppo A, Bertaglia E, Tondo C, Colella A, Mantovan R, Senatore G, et al. High prevalence of cooled tip use as compared with 8-mm tip in a multicenter Italian registry on atrial fibrillation ablation: focus on procedural safety. J Cardiovasc Med (2008) 9:888–92.
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