Accepted Manuscript Reversible mechanical atrioventricular block during cryoablation for paroxysmal atrial fibrillation with a 28 mm balloon Joel Fedida, M.D., Nicolas Badenco, M.D., Estelle Gandjbakhch, M.D., PhD, Xavier Waintraub, M.D., Francoise Hidden-Lucet, M.D., Guillaume Duthoit, M.D. PII: S2214-0271(18)30293-8 DOI: 10.1016/j.hrcr.2018.09.009 Reference: HRCR 604 To appear in: HeartRhythm Case Reports Received Date: 19 June 2018 Revised Date: 20 August 2018 Accepted Date: 19 September 2018 Please cite this article as: Fedida J, Badenco N, Gandjbakhch E, Waintraub X, Hidden-Lucet F, Duthoit G, Reversible mechanical atrioventricular block during cryoablation for paroxysmal atrial fibrillation with a 28 mm balloon, HeartRhythm Case Reports (2018), doi: https://doi.org/10.1016/j.hrcr.2018.09.009. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
1 2 3 Reversible mechanical atrioventricular block during cryoablation for paroxysmal atrial fibrillation with a 28 mm balloon Short title: Atrioventricular block during cryoablation for paroxysmal atrial fibrillation 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 JOEL FEDIDA M.D. 1,2, NICOLAS BADENCO M.D. 1, ESTELLE GANDJBAKHCH M.D., PhD 1,2, XAVIER WAINTRAUB M.D. 1, FRANCOISE.HIDDEN-LUCET M.D. 1, GUILLAUME DUTHOIT M.D. 1 1 AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Institut de Cardiologie, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, Paris, France Keyword: atrial fibrillation; ablation; cryoballoon; cryoenergy; AV block; right inferior pulmonary vein; left atrium *Corresponding author: Dr. Joël Fedida, Département de Cardiologie, AP-HP, Hôpital Pitié- Salpêtrière, 47-83 bld de l Hôpital, 75013, Paris, France. Tel: 00 33614880319. Fax: 00 33 142163057. Email: fedidajoel@gmail.com Word count: 540 Disclosures: none related to the study Introduction Cryoablation of paroxysmal atrial fibrillation is an increasingly common procedure for treatment of symptomatic patients after failure of or intolerance to antiarrhythmic drug therapy. Atrio-ventricular block during cryoablation therapy is an uncommon complication. 27 28 29 We present a case of a transient mechanical atrio-ventricular block occurring during manipulation of a 28 mm cryoballoon catheter before cryoenergy delivery around the RIPV. The main hypothesis is a mechanical bump of the AV node. 30 1
31 32 33 Case report A 52-year-old woman was referred to our center for cryoablation under general 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 anaesthesia for symptomatic paroxysmal atrial fibrillation ablation with history of documented atrial flutter. Pre-ablation CT-scan showed normal pulmonary vein distribution (fig 1A) and ECG showed complete right bundle branch block (RBBB). After transseptal puncture, left pulmonary veins isolation was performed using a 28 mm cryoballon, Arctic Front Advance, after a single application for each vein. Then, the catheter was advanced to the right inferior pulmonary vein (RIPV) with the support of an Achieve catheter. Balloon was inflated in order to isolate the RIPV but total RIPV occlusion with selective contrast injection was difficult to obtain with persistence of an inferior RIPV leak. A pull-back maneuver allowed to obtain a total occlusion (figure panel A). During this manipulation, and before cryoablation, a complete atrio-ventricular block (AVB) occurred with an escape rhythm of 40 bpm with pre-existing RBBB (figure panel B top). Despite a 30 min waiting time and intravenous injection of 100 mg hydrocortisone AV block remained complete. The procedure was continued to isolate the right superior pulmonary vein but neither cavotricuspid isthmus line with radiofrequency energy nor RIPV isolation was retried for safety reasons to avoid delivery of permanent lesions in the AV node region due to absence of AV conduction monitoring. 45 minutes later AV block spontaneously resolved when the patient woke up, during extubation. Discussion 53 54 55 AV block during cryoablation is a rare complication. Pereira Fonseca described the only actual case of AVB but during delivery of cryoenergy in the RIPV with a 28mm balloon (1). They hypothesized that AV node ischemia was the most probable mechanism as artery 2
56 57 58 coronary angiography performed 30 min after AV block showed a patent AV node artery originating from the right coronary artery. In our case, a short distance between the RIPV ostium and aortic annulus at proximity of the AV node region showed by CT-scan 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 reconstruction could explain mechanical AV bock during manipulation of the 28 mm cryoballoon catheter (13 Fr) (figure panel C). This could be due to mechanical bump of the interatrial septum and crux cordis, but also to left sided pathway of the AV-node. Data for comparison with CT-scan reconstruction are needed to confirm this hypothesis. The others different possible mechanisms of AV block during cryoablation procedure are summarized: 1) vagal reaction due to freezing/ thawing 2) inadvertent ganglionated plexus cryo-ablation/modulation 3) AV node artery vasospasm (as described by Fonseca 1 ) or coronary embolism due to air bubble migration, either in the right coronary or in the left circumflex artery 2, induced by sheath or balloon flushing 4) mechanical bump of the AV node as reported here. Conclusion Our case highlights the importance to carefully monitor AV conduction during cryoablation especially with the use of a 28 mm cryoballoon catheter during RIPV isolation in small atria. References 1. Fonseca WP, Pisani CF, Lara S, Scanavacca M. Transient complete atrioventricular block during catheter balloon cryoablation of atrial fibrillation: a case report. Europace. 1 déc 2017; 19(12):1943-1943. 2. Kawashima T, Sato F. Clarifying the anatomy of the atrioventricular node artery. International Journal of Cardiology [Internet]. 2018 Jul 5 [cited 2018 Aug 20]; Available from: http://www.sciencedirect.com/science/article/pii/s0167527318323040 3
83 84 85 86 87 88 89 90 Figure 1. A: Antero-posterior fluoroscopy view showing total occlusion of RIPV during selective angiography. B: ECG and EGM of the RIPV (A1-2 to A7-8) and the coronary sinus (SC 1-2, SC 3-4) showing AV block during manipulation of the 28mm Cryoballoon catheter as shown in figure A. C: CT-scan reconstruction showing a short distance between the RIPV ostium and aortic annulus at proximity of the AV node region. 4
Key teaching points : - AV block is a rare complication of cryoablation for paroxysmal atrial fibrillation. - It can occur with manipulation of a 28mm Cryoballoon around the RIPV in a small left atrium. Careful ECG monitoring during manipulation or cryoablation delivery around RIPV is necessary to watch occurrence of AV block. - The others different possible mechanisms of AV block during cryoablation procedure are summarized: 1) vagal reaction due to freezing/ thawing 2) inadvertent ganglionated plexus cryo-ablation/modulation 3) AV node artery vasospasm or coronary embolism due to air bubble migration, either in the right coronary or in the left circumflex artery, induced by sheath or balloon flushing 4) mechanical bump of the AV node as reported here.