- Email: [email protected]
Radiofrequency ablation in congenital heart disease: a call to arms
Heart Rhythm (2004) 1, 174 –175
www.heartrhythmjournal.com
EDITORIAL COMMENTARY
Radiofrequency ablation in congenital heart disease: A call to arms Anne M. Dubin, MD From the Division of Pediatric Cardiology, Stanford University, Palo Alto, California. Radiofrequency ablation has become the treatment of choice for nearly all cardiac arrhythmias in the pediatric population. Radiofrequency ablation in children is associated with several unique technical challenges that are not encountered in adult patients and that may complicate the procedure. These are related to the small size of the patient, effect of therapy in regard to long-term growth, and radiation exposure.1 The acute success rate for atrioventricular reciprocating tachycardia (AVRT) has been estimated at 90% in pediatric patients with structurally normal hearts.2 However, the mid- and long-term results are somewhat concerning, with a recurrence rate of 8% at 2 months following ablation, but as high as 17% for right-sided accessory pathways.3 Patients with congenital heart disease (CHD) and AVRT present an even more complicated picture. The management of these patients requires a thorough knowledge of pediatric cardiology and congenital cardiac pathology. Small studies have shown a relatively high acute success rate in these patients of 85% to 90% with a recurrence rate of 22%.4 – 6 Chetaille and colleagues have presented some disconcerting evidence that we are not doing as well as we thought in treating the combination of AVRT and CHD. They found an acute success rate of 80% in 105 procedures with a chronic success rate (4-year follow-up) of a disappointing 59%.7 They noted that 23% of their patients required 1 or more repeat ablations to achieve these results. They also emphasized the difficulties in approaching these arrhythmias: prior surgeries limited catheter access in 24% of cases and in 4 cases made ablation impossible. Their acute and Address reprint requests and correspondence: Anne Dubin, MD, Stanford University, Pediatric Cardiology, 750 Welch Road, Suite 305, Palo Alto, California 94304. E-mail address: [email protected].
chronic success rates for AVRT was similar to the results obtained in the same institution for intra-atrial reentrant tachycardia (IART)—a lesion that is known for its technically demanding nature and somewhat disappointing success rates.8 This is a problem on several levels. First, the combination of CHD and AVRT is relatively common—10% of pediatric patients reported to the Pediatric Radiofrequency Ablation registry have concomitant CHD.9 AVRT in children with CHD tends to be poorly tolerated. This is especially true of AVRT in the immediate postoperative period following congenital heart surgery repair or palliation, when medications used to support the patient’s hemodynamics may exacerbate AVRT. Thus, it has become common practice to try and eliminate known accessory pathways prior to surgery. This has become somewhat more challenging as definitive repair is being conducted in increasingly younger patients and palliative procedures that may limit access to the heart (such as extracardiac Fontan procedure) are employed more commonly. So how do we use these data knowing that AVRT elimination is crucial in CHD? The authors have previously published their results with IART and CHD.8 They analyzed whether there were any technical factors that influenced the success rate of IART ablations. While the success rates of this procedure are also somewhat lower than would be hoped, they found that newer ablative technologies directly influenced success rates for this difficult tachycardia. Specifically, they found that precise three-dimensional activation mapping systems as well as irrigated-tip ablation catheters were in part responsible for improved acute and chronic success.10 Three-dimensional activation mapping systems have been well described in the ablation of IART but may also be useful in AVRT in CHD patients. Indeed, there have been
1547-5271/$ -see front matter © 2004 Heart Rhythm Society All rights reserved. doi:10.1016/j.hrthm.2004.04.001
Dubin
Editorial commentary
case reports that have advocated the use of three-dimensional electroanatomic mapping systems in Ebstein’s malformation.11 Nonfluoroscopic catheter navigation systems are also being developed. These systems may be able to decrease fluoroscopy exposure time and more precisely localize catheter course.12 This may be especially helpful in the small patient with abnormal anatomy. There have also been advances in ablation technology. Newer, smaller catheters have allowed for ablation in the smaller patient in whom all access will be lost following CHD surgery. Irrigated-tip ablation catheters may be useful for patients in whom a deeper lesion is necessary.13 Radiofrequency ablation generators are being developed that will allow for greater energy to be delivered as well. Transvenous cryoablation has recently been introduced for clinical use in this country. Cryothermia has been used since the 1980’s for epicardial treatment of cardiac arrhythmias and has been found to be safe and effective.14,15 Transvenous cryoablation shows promise in patients with septal or AV nodal pathways.16 One of the potential advantages of cryothermia is preservation of the tissue architecture and minimal thrombus formation.17 Pediatric use of this therapy is just now being described. Finally, surgical cryoablation has recently come into favor for patients with intractable atrial arrhythmias and atriopulmonary Fontan procedures, as part of conversion to total cavopulmonary artery connection.18 Deal and colleagues have shown 100% freedom from recurrence at 34 months after a modified RA Maze procedure during Fontan revision.19 Surgical cryoablation is not a new procedure and was first described for Wolff-Parkinson-White syndrome in the 1980’s.15 As surgeons become reacquainted with this procedure, there may be a place for cryoablation of accessory pathways as part of definitive or palliative CHD surgery. Thus, Chetaille and colleagues have issued a wake-up call to us to consider AVRT in CHD the way we do IART: a difficult and serious pediatric electrophysiology problem that may require several different strategies for a successful outcome. Hopefully with newer ablation technology and the potential for surgical intervention, our results will improve.
175
4.
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14. 15.
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References 1. Friedman RA, Walsh EP, Silka MJ, Calkins H, Stevenson WG, Rhodes LA, Deal BJ, Wolff GS, Demaso DR, Hanisch D, Van Hare GF. NASPE Expert Consensus Conference: Radiofrequency catheter ablation in children with and without congenital heart disease. Report of the writing committee. North American Society of Pacing and Electrophysiology. Pacing Clin Electrophysiol 2002;25:1000 –1017. 2. Kugler JD, Danford DA, Houston K, Felix G. Radiofrequency Catheter Ablation Registry: Radiofrequency catheter ablation for paroxysmal supraventricular tachycardia in children and adolescents without structural heart disease. Am J Cardiol 1997;80:1438 –1443. 3. Van Hare GF, Carmelli D, Saul JP, Tanel RE, Fischbach PS, Kanter RJ, Schaffer S. Prospective assessment after pediatric cardiac abla-
17.
18.
19.
tion—Initial results of the multicenter study. J Am Coll Cardiol 2003; 41:483A. Van Hare GF, Lesh MD, Stanger P. Radiofrequency catheter ablation of supraventricular arrhythmias in patients with congenital heart disease: Results and technical considerations. J Am Coll Cardiol 1993; 22:883– 890. Hebe J, Hansen P, Ouyang F, Volkmer M, Kuck KH. Radiofrequency catheter ablation of tachycardia in patients with congenital heart disease. Pediatr Cardiol 2000;21:557–575. Chiou CW, Chen SA, Chiang CE, Wu TJ, Tai CT, Lee SH, Cheng CC, Ueng KC, Chen CY, Wang SP, Chiang BN, Chang MS. Radiofrequency catheter ablation of paroxysmal supraventricular tachycardia in patients with congenital heart disease. Intern J Cardiol 1995;50:143– 151. Chetaille P, Walsh EP, Triedman JK. Outcomes of radiofrequency catheter ablation of atrioventricular reciprocating tachycardia in patients with congenital heart disease. Heart Rhythm 2004;1:168 –173. Triedman JK, Bergau DM, Saul JP, Epstein MR, Walsh EP. Efficacy of radiofrequency ablation for control of intraatrial reentrant tachycardia in patients with congenital heart disease. J Am Coll Cardiol 1997;30:1032–1038. Kugler JD, Danford DA, Deal BJ, Gillette PC, Perry JC, Silka MJ, Van Hare GF, Walsh EP. Radiofrequency catheter ablation for tachyarrhythmias in children and adolescents. N Engl J Med 1994;330:1481– 1487. Triedman JK, Alexander ME, Love BA, Collins KK, Berul CI, Bevilacqua LM, Walsh EP. Influence of patient factors and ablative technologies on outcomes of radiofrequency ablation of intra-atrial reentrant tachycardia in patients with congenital heart disease. J Am Coll Cardiol 2002;39:1827–1835. Ai T, Ikeguchi S, Watanuki M, Amaya N, Ninomiya T, Horie M, Kawai C. Successful radiofrequency current catheter ablation of accessory atrioventricular pathway in Ebstein’s anomaly using electroanatomic mapping. Pacing Clin Electrophysiol 2002;25:374 –375. Kirchhof P, Loh P, Eckardt L, Ribbing M, Rolf S, Eick O, Wittkampf F, Borggrefe M, Breithardt GG, Haverkamp W. A novel nonfluoroscopic catheter visualization system (LocaLisa) to reduce radiation exposure during catheter ablation of supraventricular tachycardias. Am J Cardiol 2002;90:340 –343. Yamane T, Jais P, Shah DC, Hocini M, Peng JT, Deisenhofer I, Clementy J, Haissaguerre M. Efficacy and safety of an irrigated tip catheter for the ablation of accessory pathways resistant to conventional radiofrequency ablation. Circulation 2000;102:2565–2568. Cox JL, Holman WL, Cain ME. Cryosurgical treatment of atrioventricular node reentrant tachycardia. Circulation 1987;76:1329 –1336. Guiraudon GM, Klein GJK, Gulamhusein S, Jones DL, Yee R, Perkins DG, Jarvis E. Surgical repair of Wolff-Parkinson-White syndrome; a new closed-heart technique. Ann Thorac Surg 1984;37:67–71. Rodriguez LM, Geller JC, Tse HF, Timmerman C, Reek S, Lee KL, Ayers GM, Lau CP, Klein HU, Crijns HJ. Acute results of transvenous cryoablation of supraventricular tachycardia (atrial fibrillation, atrial flutter, Wolff-Parkinson-White syndrome, atrioventricular nodal reentry tachycardia). J Cardiovasc Electrophysiol 2002;13:1082–1089. Rodriguez LM, Leunissen J, Hoekstra A, Korteling BJ, Smeets JL, Timmermans C, Vos M, Daemen M, Wellens HJ. Tranvenous cold mapping and cryoablation of the AV node in dogs; Observations of chronic lesions and comparisons to those obtained using radiofrequency ablation. J Cardiovasc Electrophysiol 1998;9:1055–1061. Mavroudis C, Backer CL, Deal BJ, Johnsrude CL. Fontan conversion to cavopulmonary connection and arrhythmia circuit cryoablation. J Thorac Cardiovasc Surg 1998;115:547–556. Deal BJ, Mavroudis C, Backer CL, Buck SH, Johnsrude C. Comparison of anatomic isthmus block with the modified right atrial maze procedure for late atrial tachycardia in Fontan patients. Circulation 2002;106:575–579.
www.heartrhythmjournal.com
EDITORIAL COMMENTARY
Radiofrequency ablation in congenital heart disease: A call to arms Anne M. Dubin, MD From the Division of Pediatric Cardiology, Stanford University, Palo Alto, California. Radiofrequency ablation has become the treatment of choice for nearly all cardiac arrhythmias in the pediatric population. Radiofrequency ablation in children is associated with several unique technical challenges that are not encountered in adult patients and that may complicate the procedure. These are related to the small size of the patient, effect of therapy in regard to long-term growth, and radiation exposure.1 The acute success rate for atrioventricular reciprocating tachycardia (AVRT) has been estimated at 90% in pediatric patients with structurally normal hearts.2 However, the mid- and long-term results are somewhat concerning, with a recurrence rate of 8% at 2 months following ablation, but as high as 17% for right-sided accessory pathways.3 Patients with congenital heart disease (CHD) and AVRT present an even more complicated picture. The management of these patients requires a thorough knowledge of pediatric cardiology and congenital cardiac pathology. Small studies have shown a relatively high acute success rate in these patients of 85% to 90% with a recurrence rate of 22%.4 – 6 Chetaille and colleagues have presented some disconcerting evidence that we are not doing as well as we thought in treating the combination of AVRT and CHD. They found an acute success rate of 80% in 105 procedures with a chronic success rate (4-year follow-up) of a disappointing 59%.7 They noted that 23% of their patients required 1 or more repeat ablations to achieve these results. They also emphasized the difficulties in approaching these arrhythmias: prior surgeries limited catheter access in 24% of cases and in 4 cases made ablation impossible. Their acute and Address reprint requests and correspondence: Anne Dubin, MD, Stanford University, Pediatric Cardiology, 750 Welch Road, Suite 305, Palo Alto, California 94304. E-mail address: [email protected].
chronic success rates for AVRT was similar to the results obtained in the same institution for intra-atrial reentrant tachycardia (IART)—a lesion that is known for its technically demanding nature and somewhat disappointing success rates.8 This is a problem on several levels. First, the combination of CHD and AVRT is relatively common—10% of pediatric patients reported to the Pediatric Radiofrequency Ablation registry have concomitant CHD.9 AVRT in children with CHD tends to be poorly tolerated. This is especially true of AVRT in the immediate postoperative period following congenital heart surgery repair or palliation, when medications used to support the patient’s hemodynamics may exacerbate AVRT. Thus, it has become common practice to try and eliminate known accessory pathways prior to surgery. This has become somewhat more challenging as definitive repair is being conducted in increasingly younger patients and palliative procedures that may limit access to the heart (such as extracardiac Fontan procedure) are employed more commonly. So how do we use these data knowing that AVRT elimination is crucial in CHD? The authors have previously published their results with IART and CHD.8 They analyzed whether there were any technical factors that influenced the success rate of IART ablations. While the success rates of this procedure are also somewhat lower than would be hoped, they found that newer ablative technologies directly influenced success rates for this difficult tachycardia. Specifically, they found that precise three-dimensional activation mapping systems as well as irrigated-tip ablation catheters were in part responsible for improved acute and chronic success.10 Three-dimensional activation mapping systems have been well described in the ablation of IART but may also be useful in AVRT in CHD patients. Indeed, there have been
1547-5271/$ -see front matter © 2004 Heart Rhythm Society All rights reserved. doi:10.1016/j.hrthm.2004.04.001
Dubin
Editorial commentary
case reports that have advocated the use of three-dimensional electroanatomic mapping systems in Ebstein’s malformation.11 Nonfluoroscopic catheter navigation systems are also being developed. These systems may be able to decrease fluoroscopy exposure time and more precisely localize catheter course.12 This may be especially helpful in the small patient with abnormal anatomy. There have also been advances in ablation technology. Newer, smaller catheters have allowed for ablation in the smaller patient in whom all access will be lost following CHD surgery. Irrigated-tip ablation catheters may be useful for patients in whom a deeper lesion is necessary.13 Radiofrequency ablation generators are being developed that will allow for greater energy to be delivered as well. Transvenous cryoablation has recently been introduced for clinical use in this country. Cryothermia has been used since the 1980’s for epicardial treatment of cardiac arrhythmias and has been found to be safe and effective.14,15 Transvenous cryoablation shows promise in patients with septal or AV nodal pathways.16 One of the potential advantages of cryothermia is preservation of the tissue architecture and minimal thrombus formation.17 Pediatric use of this therapy is just now being described. Finally, surgical cryoablation has recently come into favor for patients with intractable atrial arrhythmias and atriopulmonary Fontan procedures, as part of conversion to total cavopulmonary artery connection.18 Deal and colleagues have shown 100% freedom from recurrence at 34 months after a modified RA Maze procedure during Fontan revision.19 Surgical cryoablation is not a new procedure and was first described for Wolff-Parkinson-White syndrome in the 1980’s.15 As surgeons become reacquainted with this procedure, there may be a place for cryoablation of accessory pathways as part of definitive or palliative CHD surgery. Thus, Chetaille and colleagues have issued a wake-up call to us to consider AVRT in CHD the way we do IART: a difficult and serious pediatric electrophysiology problem that may require several different strategies for a successful outcome. Hopefully with newer ablation technology and the potential for surgical intervention, our results will improve.
175
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14. 15.
16.
References 1. Friedman RA, Walsh EP, Silka MJ, Calkins H, Stevenson WG, Rhodes LA, Deal BJ, Wolff GS, Demaso DR, Hanisch D, Van Hare GF. NASPE Expert Consensus Conference: Radiofrequency catheter ablation in children with and without congenital heart disease. Report of the writing committee. North American Society of Pacing and Electrophysiology. Pacing Clin Electrophysiol 2002;25:1000 –1017. 2. Kugler JD, Danford DA, Houston K, Felix G. Radiofrequency Catheter Ablation Registry: Radiofrequency catheter ablation for paroxysmal supraventricular tachycardia in children and adolescents without structural heart disease. Am J Cardiol 1997;80:1438 –1443. 3. Van Hare GF, Carmelli D, Saul JP, Tanel RE, Fischbach PS, Kanter RJ, Schaffer S. Prospective assessment after pediatric cardiac abla-
17.
18.
19.
tion—Initial results of the multicenter study. J Am Coll Cardiol 2003; 41:483A. Van Hare GF, Lesh MD, Stanger P. Radiofrequency catheter ablation of supraventricular arrhythmias in patients with congenital heart disease: Results and technical considerations. J Am Coll Cardiol 1993; 22:883– 890. Hebe J, Hansen P, Ouyang F, Volkmer M, Kuck KH. Radiofrequency catheter ablation of tachycardia in patients with congenital heart disease. Pediatr Cardiol 2000;21:557–575. Chiou CW, Chen SA, Chiang CE, Wu TJ, Tai CT, Lee SH, Cheng CC, Ueng KC, Chen CY, Wang SP, Chiang BN, Chang MS. Radiofrequency catheter ablation of paroxysmal supraventricular tachycardia in patients with congenital heart disease. Intern J Cardiol 1995;50:143– 151. Chetaille P, Walsh EP, Triedman JK. Outcomes of radiofrequency catheter ablation of atrioventricular reciprocating tachycardia in patients with congenital heart disease. Heart Rhythm 2004;1:168 –173. Triedman JK, Bergau DM, Saul JP, Epstein MR, Walsh EP. Efficacy of radiofrequency ablation for control of intraatrial reentrant tachycardia in patients with congenital heart disease. J Am Coll Cardiol 1997;30:1032–1038. Kugler JD, Danford DA, Deal BJ, Gillette PC, Perry JC, Silka MJ, Van Hare GF, Walsh EP. Radiofrequency catheter ablation for tachyarrhythmias in children and adolescents. N Engl J Med 1994;330:1481– 1487. Triedman JK, Alexander ME, Love BA, Collins KK, Berul CI, Bevilacqua LM, Walsh EP. Influence of patient factors and ablative technologies on outcomes of radiofrequency ablation of intra-atrial reentrant tachycardia in patients with congenital heart disease. J Am Coll Cardiol 2002;39:1827–1835. Ai T, Ikeguchi S, Watanuki M, Amaya N, Ninomiya T, Horie M, Kawai C. Successful radiofrequency current catheter ablation of accessory atrioventricular pathway in Ebstein’s anomaly using electroanatomic mapping. Pacing Clin Electrophysiol 2002;25:374 –375. Kirchhof P, Loh P, Eckardt L, Ribbing M, Rolf S, Eick O, Wittkampf F, Borggrefe M, Breithardt GG, Haverkamp W. A novel nonfluoroscopic catheter visualization system (LocaLisa) to reduce radiation exposure during catheter ablation of supraventricular tachycardias. Am J Cardiol 2002;90:340 –343. Yamane T, Jais P, Shah DC, Hocini M, Peng JT, Deisenhofer I, Clementy J, Haissaguerre M. Efficacy and safety of an irrigated tip catheter for the ablation of accessory pathways resistant to conventional radiofrequency ablation. Circulation 2000;102:2565–2568. Cox JL, Holman WL, Cain ME. Cryosurgical treatment of atrioventricular node reentrant tachycardia. Circulation 1987;76:1329 –1336. Guiraudon GM, Klein GJK, Gulamhusein S, Jones DL, Yee R, Perkins DG, Jarvis E. Surgical repair of Wolff-Parkinson-White syndrome; a new closed-heart technique. Ann Thorac Surg 1984;37:67–71. Rodriguez LM, Geller JC, Tse HF, Timmerman C, Reek S, Lee KL, Ayers GM, Lau CP, Klein HU, Crijns HJ. Acute results of transvenous cryoablation of supraventricular tachycardia (atrial fibrillation, atrial flutter, Wolff-Parkinson-White syndrome, atrioventricular nodal reentry tachycardia). J Cardiovasc Electrophysiol 2002;13:1082–1089. Rodriguez LM, Leunissen J, Hoekstra A, Korteling BJ, Smeets JL, Timmermans C, Vos M, Daemen M, Wellens HJ. Tranvenous cold mapping and cryoablation of the AV node in dogs; Observations of chronic lesions and comparisons to those obtained using radiofrequency ablation. J Cardiovasc Electrophysiol 1998;9:1055–1061. Mavroudis C, Backer CL, Deal BJ, Johnsrude CL. Fontan conversion to cavopulmonary connection and arrhythmia circuit cryoablation. J Thorac Cardiovasc Surg 1998;115:547–556. Deal BJ, Mavroudis C, Backer CL, Buck SH, Johnsrude C. Comparison of anatomic isthmus block with the modified right atrial maze procedure for late atrial tachycardia in Fontan patients. Circulation 2002;106:575–579.