DOI: 10.1161/CIRCEP.114.002373

1

Accessory Atrioventricular Pathways Refractory to Catheter Ablation:

The Role of Percutaneous Epicardial Approach

Running title: Scanavacca et al.; Pericardial approach in WPW ablation

Maurício Ibrahim Scanavacca, MD, PhD1*; Eduardo Back Sternick, MD, PhD, FHRS2,3*;

Cristiano Pisani, MD1*; Sissy Lara, MD1; Carina Hardy, MD1; André d´Ávila, MD, PhD4;

Frederico Soares Correa, MD2; Francisco Darrieux, MD1; Denise Hachul, MD, PhD1;

Miguel Barbero Marcial, MD, PhD1; Eduardo A. Sosa, MD, PhD1

1Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo; 2Biocor Instituto, Nova Lima; 3Instituto de Pós-Graduação, Faculdade de Ciências Médicas de Minas Gerais, Belo

Horizonte; 4Hospital Cardiológico, Florianópolis, Santa Catarina, Brazil *contributed equally

Correspondence:

Mauricio I. Scanavacca, MD

Instituto do Coração (InCor) do Hospital das Clínicas

da Faculdade de Medicina

da Universidade de São Paulo

Av. Dr. Enéas de Carvalho Aguiar

44, São Paulo, SP, Brazil.

Tel/Fax: 55-11-2661-5312

E-mail: mauricio.scanavacca@gmail.com

Journal Subject Codes: [22] Ablation/ICD/surgery, [5] Arrhythmias, clinical electrophysiology, drugs

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DOI: 10.1161/CIRCEP.114.002373

2

Abstract:

Background - Epicardial mapping and ablation of accessory pathways through a subxiphoid

approach can be an alternative when endocardial or epicardial transvenous mapping has failed.

Methods and Results - We reviewed acute and long-term follow-up of 21 patients (14 males)

referred for percutaneous epicardial accessory pathway (AP) ablation. There was a median of 2

previous failed procedures. All patients were highly symptomatic, 8 had atrial fibrillation (3 with

cardiac arrest) and 13 had frequent symptomatic episodes of atrioventricular reentrant

tachycardia. Six (28.5%) patients had a successful epicardial ablation. Five (23.8%) patients

underwent a successful repeated endocardial mapping and ablation after epicardial mapping

yielded no early activation site. Epicardial mapping was helpful in guiding endocardial ablation

in 2 (9.5%) patients, showing that the earliest activation was simultaneous at the epi and

endocardium. Four (19%) patients underwent successful open-chest surgery after failing

epicardial/endocardial ablation. Two (9.5%) patients remained controlled under antiarrhythmic

drugs after unsuccessful endocardial/epicardial ablation. Two patients had a coronary sinus

diverticulum and one a right atrium to right ventricle diverticulum. Three patients acquired post-

ablation coronary sinus stenosis. There was no major complication related to pericardial access.

Conclusions - Percutaneous epicardial approach is an alternative when conventional endocardial

or transvenous epicardial ablation fails in the elimination of the accessory pathway. A new

attempt by endocardial approach was successful in a significant number of patients. Open-chest

surgery may be required in very symptomatic cases refractory to endocardial-epicardial

approach.

Key words: Wolff-Parkinson-White syndrome, epicardial, ablation, pericardium, pericardial puncture, pericardial access

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DOI: 10.1161/CIRCEP.114.002373

3

Introduction

Radiofrequency catheter ablation is currently the gold standard therapy for symptomatic patients

with accessory atrioventricular pathways. A small subset of patients, however, will fail ablation

procedures using a conventional endocardial approach. Percutaneous transthoracic pericardial

access was originally reported for the treatment of ventricular tachycardia 1-2 and gradually

became a worldwide-accepted technique for those patients with ventricular tachycardia where

the subepicardium is a component of the tachycardia circuit 3-7. Accessory pathways are

epicardial structures 8 that are usually accessible from a catheter positioned in the adjacent

endocardium, above or beneath the valvular annulus, or from the epicardial vessels of the

coronary venous system 9. In some patients, however, the accessory pathway may be located

further away from the annulus, out of reach from an endocardially positioned catheter. In

addition, associated structural abnormalities or inability to deliver radiofrequency (RF) current

may also lead to failed procedures. Clinical experience with epicardial approach for AP ablation

is limited 10-14. The aim of this study is to assess the contribution of percutaneous epicardial

mapping and ablation of accessory pathways refractory to conventional endocardial mapping.

Population and Methods

Study Population

The population consisted of 21 patients from 3 Institutions (Instituto do Coração, São Paulo

University, São Paulo, Brazil; Biocor Instituto, Nova Lima, Brazil, and Hospital Cardiólogico,

Florianopolis, Santa Catarina, Brazil) with accessory atrioventricular pathways (AP) refractory to

multiple endocardial attempts of catheter ablation between 2001 and 2013. All patients referred

to our centers underwent a simultaneous endocardial and epicardial approach. The flowchart of

the clinical-electrophysiologic decision-making process is depicted in Figure 1.

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DOI: 10.1161/CIRCEP.114.002373

4

Methods

Anatomic evaluation

Coronary sinus anatomy was assessed in 16 patients by venous angiography, with multi-slice

computer tomography in 3 patients. Cases 1 and 21 underwent magnetic resonance imaging to

assess right atrium anatomy (Table 1 and Figure 2 and 3).

Pericardial puncture

The technique was reported elsewhere 15. In 19 patients, a conventional 7F sheath was introduced

in the pericardial space. In two (#10 and #11), an 8.5F introducer was used with a steerable

pericardial sheath (Agilis®, S Jude Medical, Minneapolis, USA). Coronary angiography was

performed to check proximity of the ablation site with coronary arteries (we considered safe a

minimum distance of 5 mm) 5. A 5 Fr pigtail catheter was used to drain the accumulated

pericardial fluid in case of open irrigated-tip catheter ablation. All catheters and sheaths were

removed at the end of the procedure.

Electrophysiologic study, mapping and catheter ablation

Electrophysiologic study was performed with the EP Tracer System (Cardiotek BV, Maastricht,

The Netherlands). In general, patients with posteroseptal and left-sided accessory pathways

underwent left atrial instrumentation through transeptal puncture (13 patients), and in 2 patients a

retrograde transaortic access was also used (Table 2). Percutaneous subxiphoid pericardial access

was successfully performed in all patients. Assessment of the ablation target was based upon

early ventricular activation mapping during sinus or atrial pacing and on earliest atrial activation

site during atrioventricular reentrant tachycardia (AVRT) or ventricular pacing. Catheter ablation

with an endocardial approach (including ablation inside the middle cardiac vein and coronary

sinus) were performed with 4 or 8 mm ablation catheters except in 3 patients were an open

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DOI: 10.1161/CIRCEP.114.002373

5

irrigated-tip catheter (Thermocool®, Biosense Webster, Diamond Bar, CA, USA) was used

(Table 2). A Stockert® radiofrequency ablation generator (Biosense Webster, Johnson &

Johnson, USA) was used in all cases. Coronary angiography was performed to check proximity

to a major coronary artery branch before ablation.

Surgery

Open-chest heart surgery with cardio-pulmonary bypass and cryoablation 16 was performed in

patients with high-risk WPW-related arrhythmias after undergoing a failed endocardial-

epicardial approach. In those patients with coronary sinus diverticulum, surgery consisted of

diverticulum resection and cryoablation application with a probe to the diverticulum neck.

Follow-up

Patients underwent a transthoracic echocardiogram in the day after the procedure. Each patient

returned in the outpatient clinic at least once before 3 months after the procedure. After that

evaluation, the patient was referred back to the referring physician for long-term follow-up. The

median follow-up was 30 months (range: 1 to 133 months).

Statistical analysis

All variables are presented as median and range.

Results

Patient characteristics

Twenty-one patients were included in the study. They had undergone a median of 2 previous

ablation procedures (range 0 to 4). The median age was 29 years old (range 18 to 66), and 14

patients were males (66,7%). Eight of the 21 (38%) patients had atrial fibrillation with fast

ventricular rate, and 3 (14%) had a cardiac arrest as the presenting arrhythmia (Patient 11 stayed

10 days into a coma and underwent 15 days of hemodialysis). Seventeen patients (81%) had

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DOI: 10.1161/CIRCEP.114.002373

6

AVRT as their clinical arrhythmia (four patients had a history of AVRT and AF).

Mapping and ablation results

Epicardial mapping and ablation was successful in 6 (28.5%) patients, while in 7 (33%) a

subsequent endocardial or epicardial transvenous mapping and ablation resulted in accessory

pathway elimination. In four patients (19%), open-chest surgery was necessary for the

elimination of the accessory pathway. The other four patients (19%) had a failed endocardial and

epicardial ablation (Tables 1 and 2).

Accessory pathway localization

The most common accessory pathway position was posteroseptal in 12 (57%) patients, left free

wall and left posterior in 4 (19%), right posterior or right lateral in 3 (14,2%), and anteroseptal in

2 (9,5%). Two right-lateral accessory pathways (66,7%), three posteroseptal (25%), and one left

lateral (25%) were successfully ablated through percutaneous epicardial approach, while no

anteroseptal pathway was epicardially ablated (p=NS).

Anatomic evaluation:

Case 21 had a right atrium appendage-right ventricle diverticulum with thrombi diagnosed by

magnetic resonance imaging. Three patients were diagnosed with acquired post-ablation

coronary sinus stenosis ranging from mild (case 4) to moderate (cases 5 and 15).

Pericardial instrumentation access and complications

Pericardial access via percutaneous subxiphoid puncture was accomplished in all patients. One

patient (case 3) had hemopericardium diagnosed immediately after introduction of the dilator. In

this patient, after draining 100 mL of blood, bleeding stopped and procedure resumed without

any further bleeding. Case 19 developed acute pericarditis, which resolved with a non-steroid

anti-inflammatory drug. There were no other complications related to the catheter ablation

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procedure.

Endocardial-epicardial mapping and ablation

Figure 1 flowchart depicts outcomes in relation to activation-mapping results. Results of

activation mapping were classified in the following categories: 1) Epicardial activation earlier

than endocardial-approach activation. All six patients with earliest epicardial activation

underwent successful ablation from the epicardium. A likely AP potential was seen at the earliest

activation site in 4 of the 6 patients (Table 1 and Figures 3 and 4, as well as Figure 1

Supplemental Material); 2) Simultaneous early activation at the epi and endocardium close to the

mitral annulus was seen in three patients, and two patients were successfully ablated from the

endocardium approach, guided by epicardial mapping; 3) Endocardial approach activation was

earlier than epicardial (9 patients), the earliest activation in those 9 patients was found in the

middle cardiac vein (3 patients), coronary sinus (2 patients), an endocardial site at the tricuspid

annulus (3 patients), and at the mitral annulus (1 patient). Ablation of the accessory pathway was

successful in 2 of the 3 patients in the middle cardiac vein. Both patients with earliest activation

at the coronary sinus failed catheter ablation. Those 2 patients had acquired moderate coronary

sinus stenosis from previous ablation attempts. In all 9 patients who underwent radiofrequency

ablation attempts, the ablation sites were assessed with a coronary angiography and deemed safe

(distance greater than 5 mm).

Procedure time

The median total procedure time in this series was 200 minutes (ranged from 110 to 375

minutes).

Surgery

Four patients underwent open-chest heart surgery with cardio-pulmonary bypass and

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cryoablation (Table 2). Patient 16 had a giant coronary sinus diverticulum with multiple dilated

epicardial vessels and coronary sinus ostium atresia. Resection of the diverticulum as well as

reconstruction of the coronary sinus ostium and course was necessary in this patient (Figure 5

and 6).

Follow-up

None of the 17 patients who underwent successful catheter or surgical ablation had recurrence of

AP conduction or symptoms. Two patients (cases 3 and 20) are under antiarrhythmic drug

therapy and are asymptomatic, while one patient was referred for open irrigated-tip catheter

ablation (case 17), and case 20 was lost to follow-up.

Discussion

The major findings of this study are: 1) percutaneous epicardial approach can be an alternative

when endocardial or transvenous accessory pathway ablation fails; however, in this series, this

approach was successful in only six (28,5%) patients; 2) additional endocardial or transvenous

epicardial mapping was successful in 7 (33%) patients.

Four scenarios were identified: 1) The presence of a “true” epicardial accessory pathway

identified by an earliest activation site at the epicardium and subsequent ablation of the accessory

pathway; 2) The identification of an early epicardial activation site as a reference for successful

endocardial ablation; 3) Absence of an epicardial site showing early activation, and successful

ablation with further endocardial mapping; and 4) No epicardial or endocardial site with early

activation to allow successful ablation was found. The scenarios 2, 3, and 4 could be explained

by the epicardial fat that usually is thick and close to the AV annulus precluding accessory-

pathway mapping and elimination.

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Successful ablation from percutaneous epicardial instrumentation

Six patients were successfully ablated from a pericardial site. In 2 patients (cases 10 and 11),

maneuverability, stability, and contact force of the catheter with the tissue were much improved

using a steerable sheath (Figures 2 and 3). Both patients had an epicardial posteroseptal AP. An

irrigated-tip catheter was used in 4 of 6 patients successfully ablated from the epicardium and

probably played a role. Schweikert et al. reported epicardial mapping in a cohort of 10 patients

with refractory APs. Only three patients (30%) that presented a right atrial appendage-right

ventricle (RAA-RV) diverticulum could be ablated from the epicardium, and no other AP

location had early activation or successful ablation from the epicardium 10. We also had 1 patient

with RAA-RV diverticulum ablated from the epicardium. However, other locations like

posteroseptal, left posterior, and right posterior could also be ablated from the epicardium,

expanding the prospect of ablation to more patients with an AP not amenable to endocardial

approach ablation. Valderrabano et al. 11 reported epicardial ablation in 2 of 6 patients (33%),

one in the right free-wall and the other in the right posteroseptal region. In some patients with

diverticulum (coronary sinus or RAA-RV), with a more extensive area of contact between atrium

and ventricle, multiple endocardial and epicardial radiofrequency applications might be needed

to achieve a complete ablation 17. The “successful ablation site,” however, would be considered

epicardial if the last application was delivered from that site, but contribution from endocardial

applications to the final result must be acknowledged in such an instance. This happened in case

21 who received multiple endocardial and epicardial RF applications, but the epicardial site was

considered the site of successful ablation.

Anatomic reason for failure of percutaneous epicardial ablation

The success of percutaneous epicardial ablation in the present series (28.5%) was similar to

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previous reports by Schweikert 10 and Valderrabano 11, which were 30% and 33%, respectively.

The likely explanation for this limited success rate may be related to the anatomy of the AV

groove. Becker et al. 8examined the heart of patients with accessory pathways showing that they

are epicardial structures. There is a thick epicardial fat layer covering the region where accessory

pathways sit, which is significant enough to be a limitation to a better performance of the

percutaneous epicardial approach in most patients. Another structure that could limit the

accessory pathway elimination is the coronary artery because myocardial tissue and the

accessory pathway that are located underneath large epicardial arteries frequently remained

intact after ablation 18.

Epicardial mapping guiding endocardial ablation

The concept that epicardial mapping may enhance the effectiveness of endocardial ablation was

introduced during ventricular tachycardia ablation 19. The role of epicardial mapping in guiding

endocardial catheter ablation was previously reported 10, 11. In our series, only 3 patients had

similar activation times from endocardial and epicardium. Successful endocardial ablation was

achieved in 2. In Scheikert et al. series 10, 2 patients (one with left postero-septal AP and another

with a right postero-lateral AP) had an epicardial-guided successful endocardial ablation. In

Valderrabano et al. 11series, 4 of 6 patients had an epicardial-guided endocardial ablation (3 right

free wall and 1 left postero-septal AP).

Successful endocardial ablation unrelated to epicardial mapping

Five of 8 patients were successfully ablated from the endocardium approach after they

underwent a second round of endocardial mapping (endocardium and coronary venous system

when appropriate) following epicardial mapping. Our results in those 5 patients indicate that it is

not always correct to equal failure of epicardial mapping in finding an adequate early site of

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pt that e cardial mapping may enhance the effectiveness of endocardial ablation

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DOI: 10.1161/CIRCEP.114.002373

11

activation with indication for surgery, as suggested by Valderrabano et al. 11. We cannot explain

why the adequate site of ablation was not found during the initial endocardial mapping.

However, after a thorough pericardial mapping without finding an adequate target, the operator

was provided with critical information, which was not present before, that the endocardial

approach would be the only one standing a chance of success. As a result, more emphasis and

stamina were put forward in finding the spot from the endocardium.

Failure of catheter ablation of an accessory pathway in highly symptomatic patients

A critical decision has to be made when catheter ablation is not possible. Patients referred for

open-chest surgery usually underwent multiple procedures at different centers. In our series, a

median of 3 procedures were performed before the percutaneous epicardial approach in the

patients that underwent surgery (vs 1 without surgery). We want to stress that it is crucial to

repeat endocardium mapping after making sure that no early activation was found under the

subxyphoid epicardial approach. This made the difference in 24% of our patients.

Another important issue is the use of irrigated-tip technology. Irrigated-tip ablation

catheter was used in only 7 patients (Table 2), and a successful ablation was achieved in 4. On

the other hand, 14 patients underwent catheter ablation with regular 4mm or 8mm tip catheter,

and successful ablation was attained in 9. The use of irrigated-tip ablation catheters could have

improved results, particularly in patients with an AP located in the coronary sinus venous

system, like patients 17 and 18, who had an accessory pathway mapped inside the middle cardiac

vein (case 17 had transient disappearance of pre-excitation during RF application).

Unfortunately, we did not have the irrigated-tip technology available in all patients because some

procedures were performed before this technology was available. This important issue needs to

be prospectively addressed.

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12

The presence of an associated anatomic abnormality is not a priori an impediment to a

successful catheter ablation procedure. Successful ablation was accomplished in 1 of the 2

patients with a coronary sinus diverticulum and in the only patient with a right atrium-right

ventricle diverticulum. However, coronary sinus stenosis, caused by radiofrequency applications

inside the coronary sinus in previous procedures probably played a role in not achieving success

in the two patients that presented moderate stenosis, in one of whom open-chest surgery was

necessary. Patient 16, with a giant coronary sinus diverticulum and ostium atresia (Figures 5 and

6), is an example of the limitation of the technique: an impossible ablation. In some patients,

particularly the ones with high-risk accessory pathways, open-chest surgery might be required.

Procedure time

Electroanatomic mapping was not usually performed during AP ablation procedures. In our

series, only 1 patient underwent electroanatomic mapping (case 12). However, given the long-

lasting procedure times, the use of non-fluoroscopic imaging technique to limit radiation

exposure is advisable.

Acquired post ablation decremental conduction

Two patients (cases 11 and 21) (Table 1) showed a change in their AP electrophysiologic

characteristics, which acquired slow conduction and decremental properties while losing

ventriculo-atrial conduction capability. Sternick et al. 20 reported a series of patients with post-

ablation decremental properties and found that posteroseptal septal AP located inside the

coronary sinus venous system was at greatest risk (odds 1:6) of developing decremental

properties. They suggested that in spite of the change in A-V conduction, they were still capable

of being part of an arrhythmia circuit; therefore, they should be targeted for ablation. Cases 11

and 21 only had atrial fibrillation. Case 11 developed a Mahaim-like physiology after

ation. In some ppattieieieientnnn

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dad ii blbl

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radiofrequency current was applied in the middle cardiac vein. Atrioventricular conduction time

became decremental, but the refractory period was still short and the AP was eventually ablated

from the pericardial space (Figure 2). Case 21 had a right-lateral AP associated with a right

atrium diverticulum and after 38 applications of RF pulses, ventricular preexcitation was only

exposed during atrial pacing, ventriculo-atrial conduction was abolished and anterograde

refractory period became prolonged, which was considered a valid end-point. This patient was

asymptomatic in the long-term follow-up, without ventricular preexcitation at the ECG.

Limitations

This series included patients since 2001, and no irrigated tip catheters were available in the early

cases of this series. One could argue that if this technology were available, it could have

precluded the need for an epicardial approach in some patients, particularly those in close

proximity with the coronary venous system.

Conclusions

Epicardial ablation through percutaneous subxiphoid access was successful in a minority of

patients in whom this approach was attempted. A new attempt of endocardial mapping and

transvenous approach is highly advisable after a failed percutaneous epicardial approach. A

subset of patients may require open-chest surgery. Pericardial instrumentation was safe in this

series of patients. Anatomy evaluation conducted prior to the procedure, use of a steerable

sheath, and irrigated-tip catheters may improve patient selection and ablation results.

Conflict of Interest Disclosures: None

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withhh tttthehhehe ccoronary y venous ssssyysystem.

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References:

1. Sosa E, Scanavacca M, d’Avila A, Pilleggi F. A new technique to perform epicardial mapping in the electrophysiology laboratory. J Cardiovasc Electrophysiol. 1996;7:531–536.

2. Sosa E, Scanavacca M, d’Avila A, Piccioni J, Sanchez O, Velarde JL, Silva M, Reolão B. Endocardial and epicardial ablation guided by nonsurgical transthoracic epicardial mapping to treat recurrent ventricular tachycardia. J Cardiovasc Electrophysiol. 1998;9:229–239.

3. Tomassoni G, Stanton M, Richey M, Leonelli FM, Beheiry S, Natale A. Epicardial mapping and radiofrequency catheter ablation of ischemic ventricular tachycardia using a three-dimensional nonfluoroscopic mapping system. J Cardiovasc Electrophysiol. 1999;10:1643–1648.

4. Sosa E, Scanavacca M, d’Avila A, Oliveira F, Ramires JA. Nonsurgical transthoracic epicardial catheter ablation to treat recurrent ventricular tachycardia occurring late after myocardial infarction. J Am Coll Cardiol. 2000;35:1442–1449.

5. Viles-Gonzales JF, Miranda RC, Scanavacca M, Sosa E, d’Avila A. Acute and chronic effects of epicardial radiofrequency applications delivered on epicardial coronary arteries. Circ Arrhythmia Electrophysiolol. 2011;4:526–531.

6. Swarup V, Morton JB, Arruda M, Wilber DJ. Ablation of epicardial macroreentrant ventricular tachycardia associated with idiopathic nonischemic dilated cardiomyopathy by a percutaneous transthoracic approach. J Cardiovasc Electrophysiol. 2002;13:1164–1168.

7. Brugada J, Berruezo A, Cuesta A, Osca J, Chueca E, Fosch X, Wayar L, Mont L. Nonsurgical transthoracic epicardial radiofrequency ablation: an alternative in incessant ventricular tachycardia. J Am Coll Cardiol. 2003;41:2036–2043.

8. Becker A, Anderson R, Durrer D, Wellens H: The anatomical substrates of Wolff-Parkinson-White syndrome: A clinicopathologic correlation in seven patients. Circulation. 1978;57:870-879.

9. Sun Y, Arruda M, Otomo K, Beckman K, Nakagawa H, Calame J, Po S, Spector P, Lutsgarten D, Herring L, Lazzara R, Jackman W. Coronary sinus-ventricular accessory connections producing posteroseptal and left posterior accessory pathways. Circulation. 2002;106:1362-1367.

10. Schweikert RA, Saliba WI, Tomassoni G, Marrouche NF, Cole CR, Dressing TJ, Tchou PJ, Bash D, Beheiry S, Lam C, Kanagaratnam L, Natale A. Percutaneous pericardial instrumentation for endocardial-epicardial mapping of previously failed ablations. Circulation. 2003;108:1329-1335.

11. Valderrabano M, Cesario A, Ji S, Shannon K, Wiener I, Swerdlow CD, Oral H, Morady F, Shivkumar K. Percutaneous epicardial mapping during ablation of difficult accessory pathways

gig cal transthoracic c c cccccucucucurrrrrrrrininining g g g lalalalatetetete aaaaftftftfteerere

o eaa

Vtachycardia associated with idiopathic nonischemic dilated cardiomyopathy by

a J Berr e o A C esta A Osca J Ch eca E Fosch X Wa ar L Mont L Nons

onzazazazalelelel sss JFJFJFF, MiMiMirararar nda RC, Scanavacca M, SoSSosa E, d’Avili a A.A.A.A. Acute and chronic eaaallll rrararadiofreququqquenenenncycycy aaappppppplilililicaatitititionononons s dededelill vevevererered onon epipipicacacacardrrdr iaaaalll l cocococ rororonannn ryyyy aaaartrtrtrtererere ieii s.s.s CiCiCiC rcrcrcc a EEEElel ctrophysiiolol... 22201111;4;4;; :526262626––5331.

V, MMMMoroortoototon JBBBB, AAArA rudddda MMMM, WWWiWilber DDDDJJJJ. AAAAblblblb ttatioiii n nn ofofofof eeepppip cacaaardrdrdrdiaiii lll macrrrrororororeenttttrant tachhhhycycycy ararardididia a a asasasssososos ciciciciatatattedededed wwwitititith hh iddddioioioopapapapaththththic nnnnonononisisisischchchchemememe iciccic ddddililillatatatedededd ccccarararardidididiomomommyoyoyoopapapapaththththy y y y bybb us transthhhoracaccciciici apppppproachh.h JJJ CaCCC ddrdiiiovasc EEEllel ctroppphyhyhysiiiiolololl. 2020200202022;11113:33 11111111646464 1–1–1116161668.888

a JJ BBe AA CC tta AA OOs JJ ChCh EE FFo hh XX WW LL MMo tnt LL NNo

by guest on April 17, 2016http://circep.ahajournals.org/Downloaded from

DOI: 10.1161/CIRCEP.114.002373

15

as an alternative to cardiac surgery. Heart Rhythm. 2004;3: 311–316.

12. Saad EB, Marrouche NF, Cole CR, Natale A. Simultaneous epicardial and endocardial mapping of a left-sided posteroseptal accessory pathway associated with a large coronary sinus diverticulum: successful ablation by transection of the diverticulum’s neck. Pacing Clin Electrophysiol. 2002;25:1524-1526.

13. De Paola AAV, Leite LR, Mesas CE. Nonsurgical transthoracic epicardial ablation for the treatment of a resistant posteroseptal accessory pathway. Pacing Clin Electrophysiol.2004;27:259-261.

14. Ho I, d’Avila A, Ruskin J, Mansour M. Percutaneous epicardial mapping and ablation of a posteroseptal accessory pathway. Circulation. 2007;115:e418-e421.

15. Sosa E, Scanavacca M. Epicardial mapping and ablation techniques to control ventricular tachycardia. J Cardiovascular Electrophysiol. 2005;16:449-452.

16. Guiraudon GM, Klein GJ, Sharma AD, Jones DL, McLellan DG. Surgery for Wolff-Parkinson-White syndrome: further experience with an epicardial approach. Circulation.1986;74:525–529.

17. Lam C, Schweikert R, Kanagaratnam L, Natale A. Radiofrequency ablation of a right atrial appendage-ventricular accessory pathway by transcutaneous epicardial instrumentation. JCardiovascular Electrophysiol. 2000;11:1170-1173.

18. D'Avila A, Gutierrez P, Scanavacca M, Reddy V, Lustgarten DL, Sosa E, Ramires JA.Effects of radiofrequency pulses delivered in the vicinity of the coronary arteries: implications for nonsurgical transthoracic epicardial catheter ablation to treat ventricular tachycardia. Pacing and clinical electrophysiology. PACE. 2002;25:1488-1495.

19. Komatsu Y, Daly M, Sacher F, Cochet H, Denis A, Derval N, Jesel L, Zellerhoff S, Lim HS, Jadidi A, Nault I, Shah A, Roten L, Pascale P, Scherr D, Aurillac-Lavignolle V, Hocini M, Haïssaguerre M, Jaïs P. Endocardial ablation to eliminate epicardial arrhythmia substrate in scar-related ventricular tachycardia. J Am Coll Cardiol. 2014;63:1416-1426.

20. Sternick EB, Correa FS, Rego S, Santos DM, Damascena F, Scarpelli R, Gerken LM, Wellens HJJ. Postablation-acquired short atrioventricular Mahaim-type fibers: observations on their clinical, electrocardiographic, and electrophysiologic profile. Heart Rhythm. 2012;9:850-858.

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Table 1: Clinical characteristics of 21 patients with WPW refractory to multiple attempts at ablation

Case Gender Age Diagnosis Arrhythmia Previous Sessions

Anatomy Evaluation

Total EPICARDIALTime

AP Potential EAM Accessory

PathwayAcquired post RF

Mahaim

1 M 21 WPW AF+AVRT 4 MRI 192 No RAS

2 M 30 WPW AF+AVRT 2 angiography 120 Yes LP

3 M 22 WPW AVRT 3 angiography 330 No LAS

4 M 27 WPW AVRT 3 angiography 200 No LAL

5 M 18 WPW AVRT 3 angiography 270 No LFW

6 M 28 WPW AVRT 1 angiography 165 No LP +LFW

7 F 45 WPW AVRT 1 angiography 375 No RPS

8 F 40 WPW AVRT 1 angiography 110 No MCV+RPS

9 F 66 WPW AVRT 1 angiography 200 No RPS

10 M 29 WPW AF-CA +AVRT 2 CT 180 Yes RPS

11 M 23 WPW AF-CA 1 CT 160 Yes RPS no VA conduction short AV ERP

12 M 20 WPW AF-CA 1 CT 210 Yes Yes RPS

13 F 22 WPW AVRT 2 angiography 180 No RP

14 M 45 WPW AVRT 3 angiography 240 No RPS

15 M 27 WPW AVRT 3 angiography 240 No RPS+ RP

16 F 33 WPW AVRT 2 angiography 300 No RP

17 M 23 WPW AVRT 1 angiography 180 No PS

18 F 45 WPW AVRT 0 angiography 313 No PS

19 F 48 WPW AF 2 angiography 275 No LPS

20 M 29 WPW AF 1 angiography 186 No PS

21 M 46 WPW AF+AVRT 3 angiography+MRI 280 No RLno VA conduction

long AV ERP

Abbreviation: RFCA= Radiofrequency catheter ablation, APP= Accessory pathway potential, CA= cardiac arrest, EAM= electroanatomical mapping, EPICARDIAL= Epicardial, ERP= Effective refractory period, VA= Ventriculo-atrial.

No

NoNoNoNo

NoNoNoNo

R

Y

1111 angiography 110 No

1 anngigigigiograraaphphpp y 22202 0 NoNoNoNo

RTTTT 2222 CTCTCTCT 11811 0000 YeYeYeYes

1 CTCTCTC 1616161 0000 YeYeYeYessss

1111 CTCTCTCT 212121210000 YYeYY sss Y

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Table 2: Results of Mapping, ablation, and outcomes after ENDOCARDIAL/ EPICARDIAL approach

Case AccessoryPathway

Ablation catheter Access: EPICARDIAL/TS/RT

A/Jug/Fem/JUG

Anatomic Abnormality Earliest Activation Transient

SuccessSuccessful

RFCAIrrigated-

TipSuccesfulSurgery Complications

1 RAS EPICARDIAL/Fem/Jug No No early signals No No Yes

2 LP EPICARDIAL/TS No EPICARDIAL < Posterior vein EPICARDIAL No

3 LAS EPICARDIAL/TS/RTA No ENDOCARDIAL <EPICARDIAL No No Hemopericardium

4 LAL EPICARDIAL/TS CS stenosis CS < EPICARDIAL CS distal No Yes Yes

5 LFW EPICARDIAL/TS CS stenosis CS < EPICARDIAL CS distal No Yes Yes

6 LP +LFW EPICARDIAL/TS No ENDOCARDIAL=EPICARDIAL Endocardial No

7 RPS EPICARDIAL/Fem CS diverticulum

MCV < EPICARDIAL <ENDOCARDIAL

CS Diverticulum MCV No

8 MCV+RPS EPICARDIAL/Fem No ENDOCARDIAL <EPICARDIAL Endocardial No

9 RPS EPICARDIAL/Fem No MCV < EPICARDIAL <ENDOCARDIAL EPICARDIAL MCV No

10 RPS EPICARDIAL/TS/Fem No EPICARDIAL EPICARDIAL Yes

11 RPS EPICARDIAL/TS/Fem No EPICARDIAL MCV EPICARDIAL-RV Yes

12 RPS EPICARDIAL/TS/Fem No EPICARDIAL EPICARDIAL Yes

13 RP EPICARDIAL/Fem No EPICARDIAL EPICARDIAL No

14 RPS EPICARDIAL/Fem No ENDOCARDIAL <EPICARDIAL

ENDOCARDIAL-RV No

distaall NoNoNoNo

r

V

CSCSCSCS stenoooosssis s CS < EPICARDIALAAA CS ddddistal No

No ENEEE DODODOOCACC RDRDDIAAALLL=EPEPEPEPICCCCARARARARDIDIDIDIALALALAL EnEEndoooccar

CSCSCSC diverticululululumumumum

MCMCMCMCVV VV < << EPEPEPEPICICICICARARARA DIDDID ALALALL <<<<ENENENENDODODODOCACACACARDRDRDRDIAIAIAIALLLL

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15 RPS+ RP EPICARDIAL/TS/Fem CS stenosis ENDOCARDIAL <EPICARDIAL ENDOCARDIAL No

16 RP EPICARDIAL/Fem/Jug

CS diverticulum +CS ostium

atresia

No early signals No Yes

17 PS EPICARDIAL/TS/Fem No MCV < EPICARDIAL <ENDOCARDIAL MCV No No

18 PS EPICARDIAL/TS No MCV=EPICARDIAL No No

19 LPS EPICARDIAL/TS/RTA/Fem No ENDOCARDIAL=EPICARDIAL Endocardial No Pericarditis

20 PS EPICARDIAL/TS No No early signals No No

21 RL EPICARDIAL/Fem RA diverticulum EPICARDIAL Epicardial Yes

Abbreviations: CS= Coronary sinus, EPICARDIAL= Epicardium, Fem= femoral, Jug= Jugular, LAL= Left anterolateral, LAS= Left anteroseptal, LFW= Left free-wall, LPS= Left postero-septal, MCV= Middle cardiac vein, RAS= Right anteroseptal, RL=Right lateral, RP= Right posterior, RPS= Right posteroseptal, RTA= retrograde transortic access, RV= Right ventricle, TS= transeptal

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Figure Legends:

Figure 1: Flowchart of the management and outcomes of catheter ablation in 21 WPW patients

who underwent Endocardial/Epicardial mapping and/or ablation. Abbreviations: EPI < ENDO:

epicardial activation mapping earlier than endocardial, ENDO < EPI: endocardial activation

mapping earlier than epicardial, EPI=ENDO: isochronic endocardial and epicardial activation

mapping.

Figure 2: (A) Case 10 – Left panel shows a CT lateral view of the heart. The yellow line

represents the course of the ablation catheter in the pericardial space, from its entrance (anterior

approach) until the earliest ventricular activation site at the postero-septal region. Middle panel

shows fluoroscopic image in LAO view during right coronary artery angiography. Note the close

relationship between the ablation catheter (RF EPI) and the posterior descending branch (PDA).

Right panel shows fluoroscopic image in RAO view during levo-phase visualization of the

middle cardiac vein (white arrowheads). The ablation catheter tip (RF) is in close contact with

the middle cardiac vein (MCV). The hatched yellow line depicts the level of the annulus. The

ablation catheter tip is sitting 1.5 cm below the annulus. (B) Accessory pathway was ablated

within 4 seconds of radiofrequency current delivery through the open irrigated-tip ablation

catheter (black star). MCV: middle cardiac vein, CS os: coronary sinus ostium, EPI: Epicardium.

Figure 3: Case 11 – (A) Fluoroscopic image A (LAO 450) shows an ablation catheter in the left

septal annulus (MA) through a steerable sheath (Agilis®) introduced from transeptal puncture, a

second ablation catheter inside the middle cardiac vein (MCV), and a decapolar inside the

art. TTTThehheh yyelllelllolol w w lilinenenene

the course of the ablation catheter in the pericardial space, from its entrance (ant

u

roscopic image in LAO view during right coronary artery angiography. Note the

p

l sho s fl oroscopic image in RAO ie d ring le o phase is ali ation of the

theee ccccouououo rsrssse e ee ofoo tttthhheh ablation catheter in the ee pepep ricardial spacaa e, fffrror m its entrance (ant

uuunu tttit l the earlieestt veneentriccculuulu ar aacctivvvaatioon sitee at ththththe e e e poppop steerero-sepeptal ll l rregionononn... MiMiddlelele p

roscopopoopiciccic iiimage iiiin LAALALAO viviviviewewew durininining g iiriri hghghhttt corooonnnnaryryryry artrtterererery y angioggrarararaphphphphy. NNN ttote thhththe

ppp between thehehe aablblblblatiioi n cathhthheter (((RFRFRF EEPE IIII) ) ) and ddd hthhhe popp stterrrriioii r dededeescendidididinggg bbbbraaaancncncn hhh h (P((

ll hsh flfl iic ii ii RARAOO ii dd iin lle hph ii lalii tatiio ff thth

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coronary sinus (CS). (B) Fluoroscopic image B shows an ablation catheter inside the middle

cardiac vein, a decapolar catheter inside the coronary sinus and another ablation catheter

introduced though a pericardial steerable Agilis® sheath. The ablation catheter inside the

pericardium is located in close relation with the middle cardiac vein. Electrograms recorded from

the epicardium show an accessory pathway potential (APP) and a negative unipolar signal

steeper than the one recorded from within the middle cardiac vein. (C) Fluoroscopic image C

depicts the close relationship between the posterior descending artery (PD) and the middle

cardiac vein (star). (D) Ablation of the AP within 5 seconds of radiofrequency application with

an irrigated-tip catheter (40 watts, 30 ml/min of saline infusion). A negative T wave in inferior

leads (cardiac memory) emerged immediately (next day serum troponin rose up to 1.3 – normal

< 1). PERI: pericardium.

Figure 4: Case 3 – Upper left panel shows activation mapping with earliest activation inside a

posterior coronary sinus branch. Radiofrequency current could not be delivered due to local high

impedance (400 ohms). Upper right panel shows fluoroscopy image of the contrasted vein

(arrow). Lower left panel shows activation mapping from the epicardium (earlier than the one at

the posterior vein with an AP potential-arrow). Ablation was successfully accomplished from

this site. Lower right panel depicts the fluoroscopic image of the ablation catheter inside the

posterior vein (thin arrow) and the other in the epicardium (thick arrow). EPI: Epicardium, HRA:

high lateral right atrium.

Figure 5: Case 16 – Left panel shows 12-lead ECG during pre-excited atrial fibrillation. Middle

panel depicts during levo-phase of left ventriculography of the coronary sinus diverticulum. Note

equq encyy apppplicationononon w

gativeve TTTT wwavavee iinini iiiinfnfnfnfere

iac memory) emerged immediately (next day serum troponin rose up to 1.3 – no

C d

oronar sin s branch Radiofreq enc c rrent co ld not be deli ered d e to loca

iacccc mmmmemememorororo y)yy eeeemmemm rged immediately (nextxtxt dddday serum troooponinininn n rose up to 1.3 – no

: peeericardium...

Case 333 – UpUpUppepepeerrr r lelll ffft pppan lell shhoh ws actiivii atioiii n mappppppiiini g gg wiwithththth earararlllil est ac itiivatit onononon iiiinsid

iin bb hh RR dadiioffr tt lldd tt bbe dd lelii ded dd tt llo

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DOI: 10.1161/CIRCEP.114.002373

21

the absence of coronary sinus communication with the right atrium. Right panel shows during

activation mapping at the epicardium: despite a continuous fractionated activity (arrow) from

atrial to ventricular electrograms, epicardial ablation failed.

Figure 6: Case 16 – Left panel (A thru D) shows details from excision of the coronary sinus

diverticulum and reconstruction of the coronary sinus course and mouth. Right panel shows ECG

leads before and after surgical ablation.

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and Eduardo A. SosaAndré d'Ávila, Frederico Soares Correa, Francisco Darrieux, Denise Hachul, Miguel Barbero Marcial

Maurício Ibrahim Scanavacca, Eduardo Back Sternick, Cristiano Pisani, Sissy Lara, Carina Hardy,Percutaneous Epicardial Approach

Accessory Atrioventricular Pathways Refractory to Catheter Ablation: The Role of

Print ISSN: 1941-3149. Online ISSN: 1941-3084 Copyright © 2014 American Heart Association, Inc. All rights reserved.

Dallas, TX 75231is published by the American Heart Association, 7272 Greenville Avenue,Circulation: Arrhythmia and Electrophysiology

published online December 19, 2014;Circ Arrhythm Electrophysiol. 

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Supplemental Material

FIGURE 1 Supplemental Material: Case 2 – ECG before and after successful epicardial

ablation in a patient with left posterior AP.