Author's Accepted Manuscript
Radiofrequency catheter ablation of supraventricular tachycardia in pregnancy: Ablation without fluoroscopic exposure Mehmet Onur Omaygenc, Ibrahim Oguz Karaca, Ekrem Guler, Filiz Kizilirmak, Beytullah Cakal, Hacı Murat Gunes, Fethi Kilicaslan
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S1547-5271(15)00136-8 http://dx.doi.org/10.1016/j.hrthm.2015.01.037 HRTHM6108
To appear in:
Heart Rhythm
Cite this article as: Mehmet Onur Omaygenc, Ibrahim Oguz Karaca, Ekrem Guler, Filiz Kizilirmak, Beytullah Cakal, Hacı Murat Gunes, Fethi Kilicaslan, Radiofrequency catheter ablation of supraventricular tachycardia in pregnancy: Ablation without fluoroscopic exposure, Heart Rhythm, http://dx.doi.org/10.1016/j.hrthm.2015.01.037 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 galley proof before it is published in its final citable 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.
Radiofrequency catheter ablation of supraventricular tachycardia in pregnancy: Ablation without fluoroscopic exposure.
Mehmet Onur Omaygenc Assist Prof. 1, Ibrahim Oguz Karaca Assist. Prof.1, Ekrem Guler Assist. Prof.1, Filiz Kizilirmak Assist. Prof.1, Beytullah Cakal Assist. Prof.1, Hacı Murat Gunes Assist. Prof. 1, Fethi Kilicaslan Prof. 1
1
Istanbul Medipol University Hospital, Cardiology Dept.
Short title: Ablation without fluoroscopy in pregnancy
Corresponding author: Mehmet Onur Omaygenc
Adress for correspondance: Istanbul Medipol University Hospital. TEM Otoyolu Goztepe Cikisi No:1 P.O. 34214 Bagcilar/Istanbul/Turkey [email protected] Phone: +90 505 4424718 Phone 2: +90 212 4607774 Fax: +90 212 4607059
Word count: 3548 Conflicts of interest: None 1
Introduction Treatment of supraventricular tachycardias (SVT) during pregnancy is sometimes very troublesome. Antiarrhythmic drugs (especially beta-blockers and calcium channel blockers) are frequently used for symptomatic patients. However, routine and long-term use of these drugs is not recommended regarding to the fact that most of them are classified as categories C and D by FDA. 1 Radiofrequency catheter ablation (RFCA) may offer definitive therapy for the vast majority of these patients. However, conventional RFCA requires utilization of fluoroscopy for determination of cardiac anatomy as well as navigation of the catheters. Total fluoroscopy time may be considerably high for some cases. 2,3 Concerning the risk of potential fetal damage, ablation therapy in pregnancy is not encouraged (Class IIB, Level of Evidence C) in the contemporary guidelines. 1,4 Various statements addressing this issue had been reported so far. Some of them utilized external shielding to reduce penetration of ionizing radiation and some others used supplemantary modalities like intracardiac echocardiography and electroanatomical mapping systems (EAMS) to fascilitate catheter navigation and minimize fluoro time. 5-9 In this paper, we reported our clinical experience in three pregnant women with SVT to whom RFCA was performed using only an EAMS with no radiation exposure. Clinical cases Case 1: A 27 years-old pregnant women (21st gestational week) admitted to our hospital with the complaint of palpitation. Her recent medical history was remarkable with several symptomatic SVT attacks despite metoprolol (50 mg/day) therapy. A SVT with narrow QRS morphology were observed in emergency room and it was terminated with intravenous diltiazem administration. After restoration of sinus rhythm (SR), control ECG showed preexcitation compatible with left lateral accessory pathway. She was taken to the electrophysiology (EP) laboratory in SR at the same day. EnSite NavX™ (St. Jude Medical, St Paul, MN, USA) EAMS was used for catheter navigation during the entire procedure. Firstly, right atrium (RA) and coronary sinus (CS) anatomy was constructed. A deflectable decapolar diagnostic catheter (Inquiry™ 6F Steerable diagnostic catheter, SJM) was 2
introduced to the CS thereafter. Foramen ovale was found to be patent during catheter manipulation. Bolus unfractionated heparin (70 U/kg) was given right after left-sided access was achieved. Then, a 4 mm-tip RF catheter (RF Marinr® Multi-Curve, Medtronic Inc.) was advanced through patent foramen ovale and left atrial (LA) anatomy was constructed with the EnSite system. Maximal preexcitation was generated by atrial pacing and mitral annulus (MA) was mapped. RF was administered to the lateral MA region that had the closest AV conduction during maximal preexcitation. However, RF application here did not successfully eradicate the accessory pathway. Then, RF catheter was advanced to left ventricle retrogradely and anatomy of the left ventricle was constructed. Meanwhile, an atrioventricular reentrant tachycardia (AVRT) was induced by catheter manipulation. The closest VA conduction during AVRT was located on the lateral MA. RF application to this region immediately terminated the tachycardia. Eventually, after RFCA, there was no preexcitation, VA conduction was decremental and no AVRT was inducible. Intracardiac recording obtained during RF application and position of RF catheter on the lateral MA is displayed in Figure 1A and 1B. Case 2: A 21 years old pregnant woman (30th weeks of gestation) who had several symptomatic SVT episodes under continuous metoprolol treatment, admitted to our hospital. Her ECG revealed a SVT with a ventricular rate of 220 beats/min. EPS and ablation therapy was planned. Patient was taken to the EP laboratory in SR. RA and CS anatomy was constructed by using the EnSite system. Then, His region, AV node and slow pathway region were determined. Programmed atrial stimulation revealed AH jump and then SVT was induced. Atrioventricular nodal reentrant tachycardia (AVNRT) was diagnosed by using EP diagnostic maneuvers. A 4 mm-tip RF catheter (RF Marinr® Multi-Curve, Medtronic Inc.) was advanced to the slow pathway region under the guidance of the EnSite system and RF was applied. Junctional beats were observed during RF applications. After RFCA, programmed atrial stimulation was completely normal (no jump and echo beats) and SVT was not inducible. 12-lead ECG demonstrating the SVT and images obtained with the Ensite™ system during RF application are displayed in Figure 2A and 2B. Case 3: 25 years old primigravid patient in her 12th weeks of gestation was evaluated in the out-patient clinic. She was suffering from symptomatic paroxysmal SVT episodes despite metoprolol therapy (50 3
mg/day). She experienced near-syncope during a palpitation attack two days before her attendance. Her rest ECG revealed SR with posteroseptal preexcitation. EP study and RF ablation procedure was advised. She was transferred to EP laboratory in SR. RA anatomy was constructed with the Ensite system. A deflectable decapolar diagnostic catheter (Inquiry™ 6F Steerable diagnostic catheter, SJM) was introduced to CS. Intracardiac recordings confirmed a right-sided posteroseptal preexcitation. Tricuspid annulus was mapped during maximal preexcitation with atrial pacing. The closest AV conduction was observed in the right posteroseptal region. RF was applied there. Preexcitation was disappeared immediately during RF application. After RFCA, there was no preexcitation, VA conduction was dissociated and no SVT was inducible by programmed atrial stimulation. ECGs obtained before and after RFCA procedure and images obtained with the Ensite™ system during RF application are displayed in Figure 3A-C. In all cases we had a detailed discussion with the patient about RFCA and informed consents were taken. Fetal well-being was assessed before and after the procedure in all cases. Two of the patients gave birth to completely healthy babies. Last one is in her 24th gestational week with no signs of fetal impairment. We did not observe any periprocedural complications. None of the patients had arrhythmia recurrence and their follow-up ECGs were normal. Demographic data of the patients and each procedure was displayed in Table 1. Table 1. Clinical characteristics of three pregnant patients. Figure 1. Intracardiac recording obtained during RF application (A) and position of RF catheter on the lateral mitral annulus (B). CS, coronary sinus. HIS, His bundle. IVC, inferior vena cava. LA, left atrium. LV, left ventricle. PFO, patent foramen ovale. RA, right atrium. RF, RF catheter. SVC, superior vena cava. LAO, left anterior oblique angle. RAO, right anterior oblique angle. Figure 2. 12-lead ECG demonstrating the SVT (A) and images obtained with the Ensite™ system during RF application (B). CS, coronary sinus. HIS, His bundle. IVC, inferior vena cava. RA, right atrium. LL, left lateral angle. RAO, right anterior oblique angle.
4
Figure 3. ECGs obtained before (A) and after (B) RFCA procedure and images obtained with the Ensite™ system during RF application (C). CS, coronary sinus. HIS, His bundle. IVC, inferior vena cava. RA, right atrium. LAO, left anterior oblique angle. LL, left lateral angle. Discussion Pregnancy may aggravate symptomatic palpitation episodes. Propogated circulating levels of catecholamines and adrenergic receptor sensitivity, also hypervolemic state of the mother are pronounced as major contributory factors for this situation. 10,11 Although benign arrhythmias like premature atrial contractions are observed in almost half of otherwise healthy pregnant women, sustained SVTs are relatively rare. 11 However, almost half of the patients with a prior history of preexcitation syndrome or paroxysmal SVT episodes experience at least one symptomatic attack during gestational period. 12-14 Frequent episodes may last either in sudden decrease in cardiac output or progressive deterioration in ventricular contractile function and may have deleterious effects on fetal well-being if left untreated. 5,6,8,12 Consistent pharmacotherapy and in selected cases ablation procedure might be required for SVT attacks associated with severe symptoms or hemodynamic compromise. Owing to the fact that most of the drugs commonly used for suppressing supraventricular arrhythmias are not safe for pregnancy, RFCA is a viable treatment option. 6,10,11,15 Unfortunately, conventional RFCA requires utilization of fluoroscopy for determination of cardiac anatomy and navigation of the catheters. Amount of radiation used may be remarkable in some cases. 16 Another challenging issue about ablating an arrhythmia of a pregnant woman in second or third trimester is the risk of gastric aspiration, especially if the procedure was performed under sedoanalgesia or general anesthesia. Due to decreased gastric emptying, it is hard to achieve a definite fasting state in late pregnancy. The approximate incidence reported in the literature was about 1:8000. Fortunately, most of the cases were silent and mortality was remarkably rare. 17 Concerning this risk, all of the patients in our serie were taken into EP lab after eight-hour fasting at least. The procedures
5
were performed solely with local anesthesia and head of each patient were raised about 30 degrees. We did not observe this kind of event in our cases. Several attempts to reduce the need for fluoroscopy had been reported so far. One of them is external shielding and execution of the procedure under strict radioactive dosimeter surveillance. Several authors reported results of successful EP interventions performed with this protocol. 8,18-20 In 2010, Szumowski et al. used both external shielding and EAMS during RFCA of nine pregnant patients. 6 According to the linear-no-threshold model defined in BEIR VII document of the United States National Academies, there is a linear relationship between life-time cancer risk and radiation dose. Besides there is no threshold dose below which radiation utterly causes no harm. 21 This statement of fact raises the essentiality of abolishing -instead of lowering- the radiation exposure for this purpose especially in the first trimester of gestational period. EAMS seem to be the most practical and rational method to meet this goal. 22 Therefore, we are now performing RFCA only under the guidance of EnSite system in pregnant patients. The cases presented here are the first consecutive patients treated with EAMS guidance. We did not use external shielding in any procedure. Moreover, physicians and other laboratory staff did not wear lead aprons and protective accessories. First moderately large series that utilize an EAMS alone for ablation procedures to reduce fluoro time came from pediatric population. 23-25 The ratio of complete elimination of radiation exposure was over 80% among the total performed procedures in two of these studies. 24,25 Earley et al. compared EnSite NavXTM, CARTO (Biosense Webster, Johnson&Johnson) and conventional methods by means of procedural success, complication rates, X-ray exposure and cost analysis for adult population. They have concluded that either of two EAMS had significantly reduced radiation doses without compromising success and complication rates at the expense of increased costs. This article was not specifically focused on eliminating X-ray utilization. 26
6
Aside from case reports three recent investigations are based on non-fluoroscopic ablation procedures. 5,9,27,28
Kozluk et al. presented the largest sample population whose arrhythmias were treated by using
CARTO system. Two pregnant women were included in their series. 9 EAMS may also be used solely for ablation of even more complex arrhythmias like atrial fibrillation. Reddy et al. reported 20 consecutive paroxysmal atrial fibrillation cases successfully ablated by nonfluoroscopic approach. They utilized EnSite NavXTM system for catheter positioning, construction of left atrial geometry and localization of pulmonary veins and also facilitating the electrical isolation step. They concluded that non-fluoroscopic ablation of atrial fibrillation was safe and feasible. 28 Reddy et al. also mentioned about the practicality of ICE guidance for transseptal puncture. 28 In a recent randomized study, ICE was shown to significantly reduce the need of fluoroscopy while performing transseptal puncture, however this advantage could not be preserved when the entire procedure had been considered. 29 ICE may also be helpful for identifying left atrial anatomy, guiding catheters, obtaining three dimensional images of the structures of interest and recognizing esophageal complications during atrial fibrillation ablation. With further improvements especially in resolution, ICE may also be utilized for assessment of lesion formation. 30 Lastly, Casella et al. have reported successful RFCA to SVT patients under the guidance of EnSite system mainly without fluoroscopy. They emphasized that total procedure times were comparable to previous studies. 16 The ablation procedures in our series were also successful and there was no complication. Our geometry and total procedure times were also satisfactory. As a result, RFCA with the help of EAMS may be feasible for pregnant patients with symptomatic SVT attacks. Multicenter studies with larger sample groups are required to promote widespread utilization of this technique. Acknowledgements Nothing to declare.
7
References 1. Blomström-Lundqvist C, Scheinman MM, Aliot EM, et al.; European Society of Cardiology Committee, NASPE-Heart Rhythm Society. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias. 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 developed in collaboration with NASPE-Heart Rhythm Society. J Am Coll Cardiol. 2003 Oct 15;42(8):1493-531. Review. PubMed PMID: 14563598. 2. Perisinakis, K., Damilakis, J., Theocharopoulos, N., Manios, E., Vardas, P., Gourtsoyiannis, N. (2001). Accurate assessment of patient effective radiation dose and associated detriment risk from radiofrequency catheter ablation procedures. Circulation, 104, 58–62. PubMed PMID: 11435338. 3. Smith, I. R., Rivers, J. T., Hayes, J., Stafford, W., Codd, C. (2009). Reassessment of radiation risks from electrophysiology procedures compared to coronary angiography. Heart, Lung & Circulation, 2009 Jun;18(3):191-9. PubMed PMID: 19119073. 4. European Society of Gynecology (ESG); Association for European Paediatric Cardiology (AEPC); German Society for Gender Medicine (DGesGM), Regitz-Zagrosek V, Blomstrom Lundqvist C, Borghi C, et al.; ESC Committee for Practice Guidelines. ESC Guidelines on the management of cardiovascular diseases during pregnancy: the Task Force on the Management of Cardiovascular Diseases during Pregnancy of the European Society of Cardiology (ESC). Eur Heart J. 2011 Dec;32(24):3147-97. doi: 10.1093/eurheartj/ehr218. Epub 2011 Aug 26. PubMed PMID: 21873418. 5. Manjaly ZR, Sachdev B, Webb T, Rajappan K. Ablation of arrhythmia in pregnancy can be done safely when necessary. Eur J Obstet Gynecol Reprod Biol. 2011 Jul;157(1):116-7. doi: 10.1016/j.ejogrb.2011.01.019. Epub 2011 Feb 18. PubMed PMID: 21334130.
8
6. Szumowski L, Szufladowicz E, Orczykowski M, et al. Ablation of severe drug-resistant tachyarrhythmia during pregnancy. J Cardiovasc Electrophysiol. 2010 Aug 1;21(8):877-82. doi: 10.1111/j.1540-8167.2010.01727.x. Epub 2010 Feb 11. PubMed PMID: 20158563. 7. Bongiorni MG, Di Cori A, Soldati E, Zucchelli G, Segreti L, Solarino G, De Lucia R, Marzilli M. Radiofrequency catheter ablation of atrioventricular nodal reciprocating tachycardia using intracardiac echocardiography in pregnancy. Europace. 2008 Aug;10(8):1018-21. doi: 10.1093/europace/eun120. Epub 2008 May 6. PubMed PMID: 18460548. 8. Berruezo A, Díez GR, Berne P, Esteban M, Mont L, Brugada J. Low exposure radiation with conventional guided radiofrequency catheter ablation in pregnant women. Pacing Clin Electrophysiol. 2007 Oct;30(10):1299-302. PubMed PMID: 17897139. 9. Koźluk E, Gawrysiak M, Piątkowska A, Lodziński P, Kiliszek M, Małkowska S, Zaczek R, Piątkowski R, Opolski G, Kozłowski D. Radiofrequency ablation without the use of fluoroscopy - in what kind of patients is it feasible? Arch Med Sci. 2013 Oct 31;9(5):821-5. doi: 10.5114/aoms.2013.38676. Epub 2013 Nov 5. PubMed PMID: 24273563. 10. Moore JS, Teefey P, Rao K, Berlowitz MS, Chae SH, Yankowitz J. Maternal arrhythmia: a case report and review of the literature. Obstet Gynecol Surv. 2012 May;67(5):298-312. doi: 10.1097/OGX.0b013e318253a76e. Review. PubMed PMID: 22624778. 11. Ghosh N, Luk A, Derzko C, Dorian P, Chow CM. The acute treatment of maternal supraventricular tachycardias during pregnancy: a review of the literature. J Obstet Gynaecol Can. 2011 Jan;33(1):17-23. Review. PubMed PMID: 21272431. 12. Silversides CK, Harris L, Haberer K, Sermer M, Colman JM, Siu SC. Recurrence rates of arrhythmias during pregnancy in women with previous tachyarrhythmia and impact on fetal and neonatal outcomes. Am J Cardiol. 2006 Apr 15;97(8):1206-12. Epub 2006 Mar 3. PubMed PMID: 16616027.
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13. Kounis NG, Zavras GM, Papadaki PJ, Soufras GD, Kitrou MP, Poulos EA. Pregnancyinduced increase of supraventricular arrhythmias in Wolff-Parkinson-White syndrome. Clin Cardiol. 1995 Mar;18(3):137-40. PubMed PMID: 7743683. 14. Siu SC, Sermer M, Harrison DA, Grigoriadis E, Liu G, Sorensen S, Smallhorn JF, Farine D, Amankwah KS, Spears JC, Colman JM. Risk and predictors for pregnancy-related complications in women with heart disease. Circulation. 1997 Nov 4;96(9):2789-94. PubMed PMID: 9386139. 15. Gowda RM, Khan IA, Mehta NJ, Vasavada BC, Sacchi TJ. Cardiac arrhythmias in pregnancy: clinical and therapeutic considerations. Int J Cardiol. 2003 Apr;88(2-3):129-33. Review. PubMed PMID: 12714190. 16. Casella M, Pelargonio G, Dello Russo A, et al. "Near-zero" fluoroscopic exposure in supraventricular arrhythmia ablation using the EnSite NavX™ mapping system: personal experience and review of the literature. J Interv Card Electrophysiol. 2011 Aug;31(2):109-18. doi: 10.1007/s10840-011-9553-5. Epub 2011 Mar 2. Review. PubMed PMID: 21365263. 17. Green SM, Krauss B. Pulmonary aspiration risk during emergency department procedural sedation--an examination of the role of fasting and sedation depth. Acad Emerg Med. 2002 Jan;9(1):35-42. Review. PubMed PMID: 11772667. 18. Kanjwal Y, Kosinski D, Kanj M, Thomas W, Grubb B. Successful radiofrequency catheter ablation of left lateral accessory pathway using transseptal approach during pregnancy. J Interv Card Electrophysiol. 2005 Sep;13(3):239-42. PubMed PMID: 16177852. 19. Bombelli F, Lagona F, Salvati A, Catalfamo L, Ferrari AG, Pappone C. Radiofrequency catheter ablation in drug refractory maternal supraventricular tachycardias in advanced pregnancy. Obstet Gynecol. 2003 Nov;102(5 Pt 2):1171-3. PubMed PMID: 14607046.
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20. Domínguez A, Iturralde P, Hermosillo AG, Colin L, Kershenovich S, Garrido LM. Successful radiofrequency ablation of an accessory pathway during pregnancy. Pacing Clin Electrophysiol. 1999 Jan;22(1 Pt 1):131-4. PubMed PMID: 9990613. 21. Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation; Nuclear and Radiation Studies Board, Division on Earth and Life Studies, National Research Council of the National Academies. Health risks from exposure to low levels of ionizing radiation: BEIR VII phase 2. The National Academies Press, Washington, DC, 2006. 22. Casella M, Dello Russo A, Pelargonio G, et al. Rationale and design of the NO-PARTY trial: near-zero fluoroscopic exposure during catheter ablation of supraventricular arrhythmias in young patients. Cardiol Young. 2012 Oct;22(5):539-46. doi: 10.1017/S1047951112000042. Epub 2012 Feb 13. PubMed PMID: 22325367. 23. Drago, F., Silvetti, M. S., Di Pino, A., Grutter, G., Bevilacqua, M., Leibovich, S. Exclusion of fluoroscopy during ablation treatment of right accessory pathway in children. Journal of Cardiovascular Electrophysiology, 2002; 13, 778–82. PubMed PMID: 12212697. 24. Smith G, Clark JM. Elimination of fluoroscopy use in a pediatric electrophysiology laboratory utilizing three-dimensional mapping. Pacing Clin Electrophysiol. 2007 Apr;30(4):510-8. PubMed PMID: 17437575. 25. Tuzcu V. A nonfluoroscopic approach for electrophysiology and catheter ablation procedures using a three-dimensional navigation system. Pacing Clin Electrophysiol. 2007 Apr;30(4):519-25. PubMed PMID: 17437576. 26. Earley MJ, Showkathali R, Alzetani M, Kistler PM, Gupta D, Abrams DJ, Horrocks JA, Harris SJ, Sporton SC, Schilling RJ. Radiofrequency ablation of arrhythmias guided by nonfluoroscopic catheter location: a prospective randomized trial. Eur Heart J. 2006 May;27(10):1223-9. Epub 2006 Apr 13. PubMed PMID: 16613932.
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27. Giaccardi M, Chiodi L, Del Rosso A, Colella A. 'Zero' fluoroscopic exposure for ventricular tachycardia ablation in a patient with situs viscerum inversus totalis. Europace. 2012 Mar;14(3):449-50. doi: 10.1093/europace/eur359. Epub 2011 Nov 16. PubMed PMID: 22089170. 28. Reddy VY, Morales G, Ahmed H, Neuzil P, Dukkipati S, Kim S, Clemens J, D'Avila A. Catheter ablation of atrial fibrillation without the use of fluoroscopy. Heart Rhythm. 2010 Nov;7(11):1644-53. doi: 10.1016/j.hrthm.2010.07.011. Epub 2010 Jul 14. PubMed PMID: 20637313 29. Mah DY, Miyake CY, Sherwin ED, Walsh A, Anderson MJ, Western K, Abrams DJ, Alexander ME, Cecchin F, Walsh EP, Triedman JK. The use of an integrated electroanatomic mapping system and intracardiac echocardiography to reduce radiation exposure in children and young adults undergoing ablation of supraventricular tachycardia. Europace. 2014 Feb;16(2):277-83. doi: 10.1093/europace/eut237. Epub 2013 Aug 8. PubMed PMID: 23928735. 30. Ruisi CP, Brysiewicz N, Asnes JD, Sugeng L, Marieb M, Clancy J, Akar JG. Use of intracardiac echocardiography during atrial fibrillation ablation. Pacing Clin Electrophysiol. 2013 Jun;36(6):781-8. doi: 10.1111/pace.12030. Epub 2013 Jan 10. Review. PubMed PMID: 23305194.
12
Table 1. Clinical characteristics of three pregnant patients.
Case 1
Case 2
Case 3
Age, years
27
21
25
Gestational age, weeks
21
30
12
WPW (left-sided)
AVNRT
WPW (right-sided)
Total Fluoro Time, sec
0
0
0
Geometry Time, min
32
14
16
Total procedure time, min
45
29
36
Type of Arrhythmia
Geometry time, time consumed from the insertion of first catheter until first intracardiac ECGs are obtained. Total procedure time, time consumed from the insertion of the first catheter until removal of the catheters. WPW, Wolff Parkinson White. AVNRT, AV nodal reentrant tachycardia.
13
14
15
Radiofrequency catheter ablation of supraventricular tachycardia in pregnancy: Ablation without fluoroscopic exposure Mehmet Onur Omaygenc, Ibrahim Oguz Karaca, Ekrem Guler, Filiz Kizilirmak, Beytullah Cakal, Hacı Murat Gunes, Fethi Kilicaslan
www.elsevier.com/locate/buildenv
PII: DOI: Reference:
S1547-5271(15)00136-8 http://dx.doi.org/10.1016/j.hrthm.2015.01.037 HRTHM6108
To appear in:
Heart Rhythm
Cite this article as: Mehmet Onur Omaygenc, Ibrahim Oguz Karaca, Ekrem Guler, Filiz Kizilirmak, Beytullah Cakal, Hacı Murat Gunes, Fethi Kilicaslan, Radiofrequency catheter ablation of supraventricular tachycardia in pregnancy: Ablation without fluoroscopic exposure, Heart Rhythm, http://dx.doi.org/10.1016/j.hrthm.2015.01.037 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 galley proof before it is published in its final citable 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.
Radiofrequency catheter ablation of supraventricular tachycardia in pregnancy: Ablation without fluoroscopic exposure.
Mehmet Onur Omaygenc Assist Prof. 1, Ibrahim Oguz Karaca Assist. Prof.1, Ekrem Guler Assist. Prof.1, Filiz Kizilirmak Assist. Prof.1, Beytullah Cakal Assist. Prof.1, Hacı Murat Gunes Assist. Prof. 1, Fethi Kilicaslan Prof. 1
1
Istanbul Medipol University Hospital, Cardiology Dept.
Short title: Ablation without fluoroscopy in pregnancy
Corresponding author: Mehmet Onur Omaygenc
Adress for correspondance: Istanbul Medipol University Hospital. TEM Otoyolu Goztepe Cikisi No:1 P.O. 34214 Bagcilar/Istanbul/Turkey [email protected] Phone: +90 505 4424718 Phone 2: +90 212 4607774 Fax: +90 212 4607059
Word count: 3548 Conflicts of interest: None 1
Introduction Treatment of supraventricular tachycardias (SVT) during pregnancy is sometimes very troublesome. Antiarrhythmic drugs (especially beta-blockers and calcium channel blockers) are frequently used for symptomatic patients. However, routine and long-term use of these drugs is not recommended regarding to the fact that most of them are classified as categories C and D by FDA. 1 Radiofrequency catheter ablation (RFCA) may offer definitive therapy for the vast majority of these patients. However, conventional RFCA requires utilization of fluoroscopy for determination of cardiac anatomy as well as navigation of the catheters. Total fluoroscopy time may be considerably high for some cases. 2,3 Concerning the risk of potential fetal damage, ablation therapy in pregnancy is not encouraged (Class IIB, Level of Evidence C) in the contemporary guidelines. 1,4 Various statements addressing this issue had been reported so far. Some of them utilized external shielding to reduce penetration of ionizing radiation and some others used supplemantary modalities like intracardiac echocardiography and electroanatomical mapping systems (EAMS) to fascilitate catheter navigation and minimize fluoro time. 5-9 In this paper, we reported our clinical experience in three pregnant women with SVT to whom RFCA was performed using only an EAMS with no radiation exposure. Clinical cases Case 1: A 27 years-old pregnant women (21st gestational week) admitted to our hospital with the complaint of palpitation. Her recent medical history was remarkable with several symptomatic SVT attacks despite metoprolol (50 mg/day) therapy. A SVT with narrow QRS morphology were observed in emergency room and it was terminated with intravenous diltiazem administration. After restoration of sinus rhythm (SR), control ECG showed preexcitation compatible with left lateral accessory pathway. She was taken to the electrophysiology (EP) laboratory in SR at the same day. EnSite NavX™ (St. Jude Medical, St Paul, MN, USA) EAMS was used for catheter navigation during the entire procedure. Firstly, right atrium (RA) and coronary sinus (CS) anatomy was constructed. A deflectable decapolar diagnostic catheter (Inquiry™ 6F Steerable diagnostic catheter, SJM) was 2
introduced to the CS thereafter. Foramen ovale was found to be patent during catheter manipulation. Bolus unfractionated heparin (70 U/kg) was given right after left-sided access was achieved. Then, a 4 mm-tip RF catheter (RF Marinr® Multi-Curve, Medtronic Inc.) was advanced through patent foramen ovale and left atrial (LA) anatomy was constructed with the EnSite system. Maximal preexcitation was generated by atrial pacing and mitral annulus (MA) was mapped. RF was administered to the lateral MA region that had the closest AV conduction during maximal preexcitation. However, RF application here did not successfully eradicate the accessory pathway. Then, RF catheter was advanced to left ventricle retrogradely and anatomy of the left ventricle was constructed. Meanwhile, an atrioventricular reentrant tachycardia (AVRT) was induced by catheter manipulation. The closest VA conduction during AVRT was located on the lateral MA. RF application to this region immediately terminated the tachycardia. Eventually, after RFCA, there was no preexcitation, VA conduction was decremental and no AVRT was inducible. Intracardiac recording obtained during RF application and position of RF catheter on the lateral MA is displayed in Figure 1A and 1B. Case 2: A 21 years old pregnant woman (30th weeks of gestation) who had several symptomatic SVT episodes under continuous metoprolol treatment, admitted to our hospital. Her ECG revealed a SVT with a ventricular rate of 220 beats/min. EPS and ablation therapy was planned. Patient was taken to the EP laboratory in SR. RA and CS anatomy was constructed by using the EnSite system. Then, His region, AV node and slow pathway region were determined. Programmed atrial stimulation revealed AH jump and then SVT was induced. Atrioventricular nodal reentrant tachycardia (AVNRT) was diagnosed by using EP diagnostic maneuvers. A 4 mm-tip RF catheter (RF Marinr® Multi-Curve, Medtronic Inc.) was advanced to the slow pathway region under the guidance of the EnSite system and RF was applied. Junctional beats were observed during RF applications. After RFCA, programmed atrial stimulation was completely normal (no jump and echo beats) and SVT was not inducible. 12-lead ECG demonstrating the SVT and images obtained with the Ensite™ system during RF application are displayed in Figure 2A and 2B. Case 3: 25 years old primigravid patient in her 12th weeks of gestation was evaluated in the out-patient clinic. She was suffering from symptomatic paroxysmal SVT episodes despite metoprolol therapy (50 3
mg/day). She experienced near-syncope during a palpitation attack two days before her attendance. Her rest ECG revealed SR with posteroseptal preexcitation. EP study and RF ablation procedure was advised. She was transferred to EP laboratory in SR. RA anatomy was constructed with the Ensite system. A deflectable decapolar diagnostic catheter (Inquiry™ 6F Steerable diagnostic catheter, SJM) was introduced to CS. Intracardiac recordings confirmed a right-sided posteroseptal preexcitation. Tricuspid annulus was mapped during maximal preexcitation with atrial pacing. The closest AV conduction was observed in the right posteroseptal region. RF was applied there. Preexcitation was disappeared immediately during RF application. After RFCA, there was no preexcitation, VA conduction was dissociated and no SVT was inducible by programmed atrial stimulation. ECGs obtained before and after RFCA procedure and images obtained with the Ensite™ system during RF application are displayed in Figure 3A-C. In all cases we had a detailed discussion with the patient about RFCA and informed consents were taken. Fetal well-being was assessed before and after the procedure in all cases. Two of the patients gave birth to completely healthy babies. Last one is in her 24th gestational week with no signs of fetal impairment. We did not observe any periprocedural complications. None of the patients had arrhythmia recurrence and their follow-up ECGs were normal. Demographic data of the patients and each procedure was displayed in Table 1. Table 1. Clinical characteristics of three pregnant patients. Figure 1. Intracardiac recording obtained during RF application (A) and position of RF catheter on the lateral mitral annulus (B). CS, coronary sinus. HIS, His bundle. IVC, inferior vena cava. LA, left atrium. LV, left ventricle. PFO, patent foramen ovale. RA, right atrium. RF, RF catheter. SVC, superior vena cava. LAO, left anterior oblique angle. RAO, right anterior oblique angle. Figure 2. 12-lead ECG demonstrating the SVT (A) and images obtained with the Ensite™ system during RF application (B). CS, coronary sinus. HIS, His bundle. IVC, inferior vena cava. RA, right atrium. LL, left lateral angle. RAO, right anterior oblique angle.
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Figure 3. ECGs obtained before (A) and after (B) RFCA procedure and images obtained with the Ensite™ system during RF application (C). CS, coronary sinus. HIS, His bundle. IVC, inferior vena cava. RA, right atrium. LAO, left anterior oblique angle. LL, left lateral angle. Discussion Pregnancy may aggravate symptomatic palpitation episodes. Propogated circulating levels of catecholamines and adrenergic receptor sensitivity, also hypervolemic state of the mother are pronounced as major contributory factors for this situation. 10,11 Although benign arrhythmias like premature atrial contractions are observed in almost half of otherwise healthy pregnant women, sustained SVTs are relatively rare. 11 However, almost half of the patients with a prior history of preexcitation syndrome or paroxysmal SVT episodes experience at least one symptomatic attack during gestational period. 12-14 Frequent episodes may last either in sudden decrease in cardiac output or progressive deterioration in ventricular contractile function and may have deleterious effects on fetal well-being if left untreated. 5,6,8,12 Consistent pharmacotherapy and in selected cases ablation procedure might be required for SVT attacks associated with severe symptoms or hemodynamic compromise. Owing to the fact that most of the drugs commonly used for suppressing supraventricular arrhythmias are not safe for pregnancy, RFCA is a viable treatment option. 6,10,11,15 Unfortunately, conventional RFCA requires utilization of fluoroscopy for determination of cardiac anatomy and navigation of the catheters. Amount of radiation used may be remarkable in some cases. 16 Another challenging issue about ablating an arrhythmia of a pregnant woman in second or third trimester is the risk of gastric aspiration, especially if the procedure was performed under sedoanalgesia or general anesthesia. Due to decreased gastric emptying, it is hard to achieve a definite fasting state in late pregnancy. The approximate incidence reported in the literature was about 1:8000. Fortunately, most of the cases were silent and mortality was remarkably rare. 17 Concerning this risk, all of the patients in our serie were taken into EP lab after eight-hour fasting at least. The procedures
5
were performed solely with local anesthesia and head of each patient were raised about 30 degrees. We did not observe this kind of event in our cases. Several attempts to reduce the need for fluoroscopy had been reported so far. One of them is external shielding and execution of the procedure under strict radioactive dosimeter surveillance. Several authors reported results of successful EP interventions performed with this protocol. 8,18-20 In 2010, Szumowski et al. used both external shielding and EAMS during RFCA of nine pregnant patients. 6 According to the linear-no-threshold model defined in BEIR VII document of the United States National Academies, there is a linear relationship between life-time cancer risk and radiation dose. Besides there is no threshold dose below which radiation utterly causes no harm. 21 This statement of fact raises the essentiality of abolishing -instead of lowering- the radiation exposure for this purpose especially in the first trimester of gestational period. EAMS seem to be the most practical and rational method to meet this goal. 22 Therefore, we are now performing RFCA only under the guidance of EnSite system in pregnant patients. The cases presented here are the first consecutive patients treated with EAMS guidance. We did not use external shielding in any procedure. Moreover, physicians and other laboratory staff did not wear lead aprons and protective accessories. First moderately large series that utilize an EAMS alone for ablation procedures to reduce fluoro time came from pediatric population. 23-25 The ratio of complete elimination of radiation exposure was over 80% among the total performed procedures in two of these studies. 24,25 Earley et al. compared EnSite NavXTM, CARTO (Biosense Webster, Johnson&Johnson) and conventional methods by means of procedural success, complication rates, X-ray exposure and cost analysis for adult population. They have concluded that either of two EAMS had significantly reduced radiation doses without compromising success and complication rates at the expense of increased costs. This article was not specifically focused on eliminating X-ray utilization. 26
6
Aside from case reports three recent investigations are based on non-fluoroscopic ablation procedures. 5,9,27,28
Kozluk et al. presented the largest sample population whose arrhythmias were treated by using
CARTO system. Two pregnant women were included in their series. 9 EAMS may also be used solely for ablation of even more complex arrhythmias like atrial fibrillation. Reddy et al. reported 20 consecutive paroxysmal atrial fibrillation cases successfully ablated by nonfluoroscopic approach. They utilized EnSite NavXTM system for catheter positioning, construction of left atrial geometry and localization of pulmonary veins and also facilitating the electrical isolation step. They concluded that non-fluoroscopic ablation of atrial fibrillation was safe and feasible. 28 Reddy et al. also mentioned about the practicality of ICE guidance for transseptal puncture. 28 In a recent randomized study, ICE was shown to significantly reduce the need of fluoroscopy while performing transseptal puncture, however this advantage could not be preserved when the entire procedure had been considered. 29 ICE may also be helpful for identifying left atrial anatomy, guiding catheters, obtaining three dimensional images of the structures of interest and recognizing esophageal complications during atrial fibrillation ablation. With further improvements especially in resolution, ICE may also be utilized for assessment of lesion formation. 30 Lastly, Casella et al. have reported successful RFCA to SVT patients under the guidance of EnSite system mainly without fluoroscopy. They emphasized that total procedure times were comparable to previous studies. 16 The ablation procedures in our series were also successful and there was no complication. Our geometry and total procedure times were also satisfactory. As a result, RFCA with the help of EAMS may be feasible for pregnant patients with symptomatic SVT attacks. Multicenter studies with larger sample groups are required to promote widespread utilization of this technique. Acknowledgements Nothing to declare.
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6. Szumowski L, Szufladowicz E, Orczykowski M, et al. Ablation of severe drug-resistant tachyarrhythmia during pregnancy. J Cardiovasc Electrophysiol. 2010 Aug 1;21(8):877-82. doi: 10.1111/j.1540-8167.2010.01727.x. Epub 2010 Feb 11. PubMed PMID: 20158563. 7. Bongiorni MG, Di Cori A, Soldati E, Zucchelli G, Segreti L, Solarino G, De Lucia R, Marzilli M. Radiofrequency catheter ablation of atrioventricular nodal reciprocating tachycardia using intracardiac echocardiography in pregnancy. Europace. 2008 Aug;10(8):1018-21. doi: 10.1093/europace/eun120. Epub 2008 May 6. PubMed PMID: 18460548. 8. Berruezo A, Díez GR, Berne P, Esteban M, Mont L, Brugada J. Low exposure radiation with conventional guided radiofrequency catheter ablation in pregnant women. Pacing Clin Electrophysiol. 2007 Oct;30(10):1299-302. PubMed PMID: 17897139. 9. Koźluk E, Gawrysiak M, Piątkowska A, Lodziński P, Kiliszek M, Małkowska S, Zaczek R, Piątkowski R, Opolski G, Kozłowski D. Radiofrequency ablation without the use of fluoroscopy - in what kind of patients is it feasible? Arch Med Sci. 2013 Oct 31;9(5):821-5. doi: 10.5114/aoms.2013.38676. Epub 2013 Nov 5. PubMed PMID: 24273563. 10. Moore JS, Teefey P, Rao K, Berlowitz MS, Chae SH, Yankowitz J. Maternal arrhythmia: a case report and review of the literature. Obstet Gynecol Surv. 2012 May;67(5):298-312. doi: 10.1097/OGX.0b013e318253a76e. Review. PubMed PMID: 22624778. 11. Ghosh N, Luk A, Derzko C, Dorian P, Chow CM. The acute treatment of maternal supraventricular tachycardias during pregnancy: a review of the literature. J Obstet Gynaecol Can. 2011 Jan;33(1):17-23. Review. PubMed PMID: 21272431. 12. Silversides CK, Harris L, Haberer K, Sermer M, Colman JM, Siu SC. Recurrence rates of arrhythmias during pregnancy in women with previous tachyarrhythmia and impact on fetal and neonatal outcomes. Am J Cardiol. 2006 Apr 15;97(8):1206-12. Epub 2006 Mar 3. PubMed PMID: 16616027.
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13. Kounis NG, Zavras GM, Papadaki PJ, Soufras GD, Kitrou MP, Poulos EA. Pregnancyinduced increase of supraventricular arrhythmias in Wolff-Parkinson-White syndrome. Clin Cardiol. 1995 Mar;18(3):137-40. PubMed PMID: 7743683. 14. Siu SC, Sermer M, Harrison DA, Grigoriadis E, Liu G, Sorensen S, Smallhorn JF, Farine D, Amankwah KS, Spears JC, Colman JM. Risk and predictors for pregnancy-related complications in women with heart disease. Circulation. 1997 Nov 4;96(9):2789-94. PubMed PMID: 9386139. 15. Gowda RM, Khan IA, Mehta NJ, Vasavada BC, Sacchi TJ. Cardiac arrhythmias in pregnancy: clinical and therapeutic considerations. Int J Cardiol. 2003 Apr;88(2-3):129-33. Review. PubMed PMID: 12714190. 16. Casella M, Pelargonio G, Dello Russo A, et al. "Near-zero" fluoroscopic exposure in supraventricular arrhythmia ablation using the EnSite NavX™ mapping system: personal experience and review of the literature. J Interv Card Electrophysiol. 2011 Aug;31(2):109-18. doi: 10.1007/s10840-011-9553-5. Epub 2011 Mar 2. Review. PubMed PMID: 21365263. 17. Green SM, Krauss B. Pulmonary aspiration risk during emergency department procedural sedation--an examination of the role of fasting and sedation depth. Acad Emerg Med. 2002 Jan;9(1):35-42. Review. PubMed PMID: 11772667. 18. Kanjwal Y, Kosinski D, Kanj M, Thomas W, Grubb B. Successful radiofrequency catheter ablation of left lateral accessory pathway using transseptal approach during pregnancy. J Interv Card Electrophysiol. 2005 Sep;13(3):239-42. PubMed PMID: 16177852. 19. Bombelli F, Lagona F, Salvati A, Catalfamo L, Ferrari AG, Pappone C. Radiofrequency catheter ablation in drug refractory maternal supraventricular tachycardias in advanced pregnancy. Obstet Gynecol. 2003 Nov;102(5 Pt 2):1171-3. PubMed PMID: 14607046.
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20. Domínguez A, Iturralde P, Hermosillo AG, Colin L, Kershenovich S, Garrido LM. Successful radiofrequency ablation of an accessory pathway during pregnancy. Pacing Clin Electrophysiol. 1999 Jan;22(1 Pt 1):131-4. PubMed PMID: 9990613. 21. Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation; Nuclear and Radiation Studies Board, Division on Earth and Life Studies, National Research Council of the National Academies. Health risks from exposure to low levels of ionizing radiation: BEIR VII phase 2. The National Academies Press, Washington, DC, 2006. 22. Casella M, Dello Russo A, Pelargonio G, et al. Rationale and design of the NO-PARTY trial: near-zero fluoroscopic exposure during catheter ablation of supraventricular arrhythmias in young patients. Cardiol Young. 2012 Oct;22(5):539-46. doi: 10.1017/S1047951112000042. Epub 2012 Feb 13. PubMed PMID: 22325367. 23. Drago, F., Silvetti, M. S., Di Pino, A., Grutter, G., Bevilacqua, M., Leibovich, S. Exclusion of fluoroscopy during ablation treatment of right accessory pathway in children. Journal of Cardiovascular Electrophysiology, 2002; 13, 778–82. PubMed PMID: 12212697. 24. Smith G, Clark JM. Elimination of fluoroscopy use in a pediatric electrophysiology laboratory utilizing three-dimensional mapping. Pacing Clin Electrophysiol. 2007 Apr;30(4):510-8. PubMed PMID: 17437575. 25. Tuzcu V. A nonfluoroscopic approach for electrophysiology and catheter ablation procedures using a three-dimensional navigation system. Pacing Clin Electrophysiol. 2007 Apr;30(4):519-25. PubMed PMID: 17437576. 26. Earley MJ, Showkathali R, Alzetani M, Kistler PM, Gupta D, Abrams DJ, Horrocks JA, Harris SJ, Sporton SC, Schilling RJ. Radiofrequency ablation of arrhythmias guided by nonfluoroscopic catheter location: a prospective randomized trial. Eur Heart J. 2006 May;27(10):1223-9. Epub 2006 Apr 13. PubMed PMID: 16613932.
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27. Giaccardi M, Chiodi L, Del Rosso A, Colella A. 'Zero' fluoroscopic exposure for ventricular tachycardia ablation in a patient with situs viscerum inversus totalis. Europace. 2012 Mar;14(3):449-50. doi: 10.1093/europace/eur359. Epub 2011 Nov 16. PubMed PMID: 22089170. 28. Reddy VY, Morales G, Ahmed H, Neuzil P, Dukkipati S, Kim S, Clemens J, D'Avila A. Catheter ablation of atrial fibrillation without the use of fluoroscopy. Heart Rhythm. 2010 Nov;7(11):1644-53. doi: 10.1016/j.hrthm.2010.07.011. Epub 2010 Jul 14. PubMed PMID: 20637313 29. Mah DY, Miyake CY, Sherwin ED, Walsh A, Anderson MJ, Western K, Abrams DJ, Alexander ME, Cecchin F, Walsh EP, Triedman JK. The use of an integrated electroanatomic mapping system and intracardiac echocardiography to reduce radiation exposure in children and young adults undergoing ablation of supraventricular tachycardia. Europace. 2014 Feb;16(2):277-83. doi: 10.1093/europace/eut237. Epub 2013 Aug 8. PubMed PMID: 23928735. 30. Ruisi CP, Brysiewicz N, Asnes JD, Sugeng L, Marieb M, Clancy J, Akar JG. Use of intracardiac echocardiography during atrial fibrillation ablation. Pacing Clin Electrophysiol. 2013 Jun;36(6):781-8. doi: 10.1111/pace.12030. Epub 2013 Jan 10. Review. PubMed PMID: 23305194.
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Table 1. Clinical characteristics of three pregnant patients.
Case 1
Case 2
Case 3
Age, years
27
21
25
Gestational age, weeks
21
30
12
WPW (left-sided)
AVNRT
WPW (right-sided)
Total Fluoro Time, sec
0
0
0
Geometry Time, min
32
14
16
Total procedure time, min
45
29
36
Type of Arrhythmia
Geometry time, time consumed from the insertion of first catheter until first intracardiac ECGs are obtained. Total procedure time, time consumed from the insertion of the first catheter until removal of the catheters. WPW, Wolff Parkinson White. AVNRT, AV nodal reentrant tachycardia.
13
14
15
