ORIGINAL ARTICLE
Intracardiac rhabdomyomas producing
symptoms in infancy: the role
of
radiofrequency catheter ablation M. Emmel, K. Brockmeier, N. Sreeram
Background. Cardiac rhabdomyomas, although benign, may produce symptoms related to arrhythmia or mechanical obstruction. Surgical excision is the therapy of choice for symptomatic rhabdomyomas in infancy. Patients and Meods. Two infants with intracardiac rhabdomyomas producing symptoms underwent radiofequency catheter ablation of the tumour. In patient 1 the diagnosis of multiple rhabdomyomas associated with recurrent supraventricular tachyarrhytbmias and foetal hydrops was made in utero. After birth, several antiarrhythmic agents were adminstered, without successful suppression of the tachyarrhythmia. At seven months of age, the infant had one large residual tumour on the left atrial aspect ofthe anterior mitral valve leaflet with associated pre-excitation and re-entrant supraventricular tachyarrhythmia suggestive of a leftsided pathway. Catheter ablation of the accessory pathway was performed via a retrograde femoral arterial approach, targeting the earliest site of ventricular activation. Patient 2 presented as a neonate with multiple rhabdomyomas, one of which, measuring 15 mm x 15 mm, was producing severe mitral valve inflow obstruction resulting in symptoms of heart failure due to a large left-toright shunt at atrial level and persistent pulmonary hypertension. Via the femoral vein, a 5F ablation catheter was advanced across the atrial septum, and the tumour directly ablated. Results. Echocardiography performed 24 hours later demonstrated alteration in tumour morphology, with the development of a large central M. Emmel K. Brockmelr N. Smrwam Department of Paediatric Cardiology, University Hospital of Cologne, Cologne, Germany
Correspondence to: N. Sreeram Department of Paediatric Cardiology, University Hospital of Cologne, KerpenerstraRe 62, 50937 Cologne, Germany. E-mail: [email protected]
#C
Netherlands Heart Journal, Volume 14, Number 6, June 2006
echolucent area, followed by progressive tumour sbninkage in both infants. Patient 1 was disharged at 24 hours, and patient 2 at seven days postablation, without symptoms. Follow-up at four weeks confirmed further tumour shrinkage. Conclusion. Transcatheter tumour ablation may be beneficial in selected infants and children. (Neth HeartJ2006;14;215-18.)
Keywords: rhabdomyoma, ablation
Rhabdomyomas are the most frequent intracardiac tumours found in foetuses, infants and children, and occur almost exclusively in patients under the age of 15 years.' Their size may vary from a few millimetres to several centimetres. Tuberous sclerosis is present in over 50% of the patients found to have rhabdomyomas.2 Spontaneous regression of the tumour is possible, and has been well demonstrated by echocardiographic follow-up.3 The clinical profile is often dominated by signs oftuberous sclerosis. Occasionally, however, rhabdomyomas may be the immediate cause of morbidity or mortality, and in general the prognosis ofchildren with symptomatic rhabdomyoma is poor.4'5 The major cause ofsymptoms is intracavitay obstruction to blood flow, or the association with potentially lifethreatening arrhythmias.I Surgical excision has hitherto been recommended for symptomatic tumours. Complete removal however is not always possible.6'7 We report transcatheter ablation ofintracardiac rhabdomyomas producing symptoms in two infants.
Patlent I In this patient recurrent tachyarrhythmias with a 1:1 atrioventricular relationship suggestive of a re-entrant supraventricular tachycardia, associated with the development offoetal hydrops, was diagnosed in utero at 34 weeks of gestation. Echocardiography demonstrated multiple intracardiac rhabdomyomas. Following a trial of maternal digoxin therapy, the foetus was delivered at 38 weeks' gestation. Posmatally the infant had recurrent supraventricular tachycardia, associated with ventricular pre-excitation during sinus 215
_r- - - .-_ . . - . _.: .
Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation
.
;
6
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.
.. .
. * s
L. e
....
.......
. . . ;. . . . . ;. . .. . .,,,...-,.,; *.. ........... ,4 ,.4 vi.................................................
.......
.s.*................ , , " Fb*8 ..... ....... . .....'¢ lo @A. ._ .¢8........................................_1......-.;.... 1.
*@* :z*z lw .¢@ -,:o** .bs*. @e .4 .jas
vs.9w*t
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it
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+ *e**i
I
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:
W4 W.,.. . .W!~ ~ ~ ~ ~ ~. . . .
#
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....... . .. ...t ........~~~~~~~~~~~~~~ ....._.....b88*|*s*__w__*__4 ~ _,.... .. _. .......... .. --!h-
Figure 1. Singk-kad ECG showing spontaneous termination of re-entrant supraventricular tachycardia in patient 1. 7'be sinm beats confirm maniftst ventricularpre-excitation.
rhythm (figure 1). Despite therapy with up to four antiarrhythmic agents (digoxin, propranolol, propafenone and amiodarone in various combinations) the infant continued to have episodes of tachyarrhythmia with signs ofmfld dflated cardiomyopathy, presumed to be due to the tachyarrhythmia. At seven months of age, only one large rhabdomyoma was present, in the left
AV groove on the left atrial aspect ofthe anterior leaflet ofthe n-iitral valve.
obtained, an invasive electrophysiology study was perfonned to ablate the accessory pathway. Under general anaesthesia, a 5F ablation catheter (Marinr, Medtronic) was advanced retrogradely via the femoral artery into the left ventricle.
After informed
symptoms.
consent was
retrograde atrial activation during tachyarrhythmia, and earhest ventricular activation in sinus rhythm were localised to the anterior aspect ofthe left AV groove. Defivery of radiofrequency energy to this site resulted in abolition of pre-excitation, and noninducibility of tachyarrhythmia. The catheter ablation procedure was guided entirely by intracardiac electrical Earliest
recordings, with no attention being paid to the relation of the accessory pathway to the location of the tumour. Echocardiography performed 24 hours later demonstrated a morphological change in the tumour, with a central area of echolucency suggestive of hquefaction necrosis (figures 2A and 2B). Follow-up echocardiography demonstrated further tumour shrinkage associated with scar formation (figure 2C). At eight months of foHow-up the patient has remained without Patient 2 In patient 2 multiple intracardiac rhabdomyomas were diagnosed in utero. After spontaneous defivery (birth weight 2.9 kg), the patient developed signs of heart failure associated with a large tumour in the left atrium
severe mitral inflow obstruction. The resulted in a large left-to-right shunt via the foramen ovale, associated with persistent pulmonary of hypertension. As an altemative to surgical resection the tumourl, catheter ablation was undertaken at two weeks of age.
producing tumour
-----------
MM....
.=
-.W
MWAMMO-1-
.1
..I
Figure 2A. Echoeardiograpbk appearance Figure 2B. Tumour appearance 24 hours Figure 2C Tumour appearance sixweeks after of the tumour, in the parasternal longs-axis after ablation, demonstrating a eentral ablation. 7'be tumour bas sbrunkfurOver, and the eebolueeney is repl"ed by an irregular eekolueent area. projeetion, prior to catheter ablation. echodense mass suggesting tumour zart4ng. 216
Nethcrlands Hcart Joumal, Volume 14, Number 6, junc 2006
qc
Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation
Figure3A Transophagelechocardiogram Figure 3B. Tumour appearance 24 hours Figure 3C. Tumour appearance four weeks demonstrating the kft atial tumour in pa- after ablation, showing the developmnt ofa afterablation, showinga similarsequence of tient 2, which appears to obstruct the mitral central echolucent area. morphological changes as in patient 1. valve.
Under transoesophageal echocardiographic guidance, a 5F ablation catheter was advanced from the femoral vein across the atrial septum. Good contact with the tumour was confirmed by a combination of echocardiography and the local electrical signals from the tumour, which appear as fast conducting, myocardial signals not different from normal atrial electrograms. A total of45 lesions (a lesion was defined as application of radiofrequency current to reach a temperature of 60 °C for 60 seconds) were applied directly to the tumour. There were no procedure-related complications. Within 48 hours of ablation, the tumour showed similar morphological changes as in patient 1, with improved mitral valve inflow and relief of symptoms (figures 3A and 3B). The infant was discharged from hospital at seven days after ablation, and anticongestive medications were discontinued at 14 days. At four weeks of follow-up the tumour had shrunk further, associated with scar formation (figure 3C).
Discussion Rhabdomyomas are the commonest form of intracardiac tumours, and the majority are diagnosed within the first year of life.2 The association between intracardiac tumours and arrhythmias has been well recognised, and direct electrophysiological data suggesting that the tumour is indeed the source of the arrhythmia have been offered in individual case reports.8-'0 Ross et al. described a child with atrial ectopic tachycardia, in whom surgical removal of a right atrial rhabdomyoma was associated with resolution of tachyarrhythmia." Mas et al. described a neonate presenting with recurrent atrioventricular tachycardia and multiple rhabdomyomas, in whom spontaneous regression of the rhabdomyomas was associated with loss of ventricular pre-excitation and freedom from symptoms.12 Van Hare et al. reported catheter ablation in the vicinity of the tumour (visualised by echocardiographic demonstration ofthe Netherlands Heart Journal, Volume 14, Number 6, June 2006
proximity of the ablation catheter to the tumour), which cured the tachyarrhythmia.'3 In the first patient described here, placement of discrete endocardial lesions on the ventricular aspect of the mitral valve resulted in loss of pre-excitation, with associated changes in tumour morphology, providing electrical and morphological evidence ofthe tumour itselfbeing the accessory pathway. Considering a discrete RF lesion at the site ofearliest ventricular electrical breakthrough resulted in both loss ofventricular pre-excitation and associated changes in the structure ofthe tumour, the most likely explanation is that the tumour itself, by straddling the atrioventricular groove, was functionally the accessory atrioventricular pathway. Based on the observation that tumour reduction could be achieved by direct application of radiofrequency current, we proceeded to directly target the tumour for ablation in patient 2, with a view to reducing the tumour mass and relieving symptoms of mitral valve obstruction. While a theoretical risk of tumour embolisation cannot completely be excluded, the tumour had all the echocardiographic characteristics of myocardial tissue, and was in this respect not comparable with a myxoma, which is more likely to result in systemic thromboembolic complications.'4 Rhabdomyomas, on the contrary, although not malignant tumours are more likely to cause symptoms related directly to tumour bulk, and the resulting intracavitary obstruction. To our knowledge, spontaneous embolisation of a rhabdomyoma has not previously been described. Additionally, there is a wealth ofexperience with catheter ablation of left atrial or left ventricular myocardium in adults and children with a wide variety of arrhythmias. These procedures are also not associated with a long-term risk of thromboembolic complications when antiplatelet drug therapy is routinely administered following ablation procedures. In view of these prior observations, catheter ablation of the tumour was felt to be justified. The catheter approach was facilitated by the presence 217
Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation
of a large interatrial communication, providing access to the tumour from the femoral vein. Although no immediate reduction in tumour size was noted', a similar sequence of echocardiographic changes as observed in patient 1 was also seen in patient 2, with reduction in tumour bulk accompanying relief of symptoms, allowing cessation of pharmacological antifiilure therapy. These preliminary data suggest a role for radiofrequency catheter ablation as an alternative to surgery for treatment of symptomatic intracardiac tumours. E References 1
2
3 4
5
Gatzoulis MA, Becker AE. Cardiac tumours. In Anderson RH, Baker EJ, Macartney FJ, Rigby ML, Shinebourne EA, Tynan M (editors). Paediatric Cardiology 2"d Edition. Churchill Livingstone, London, 2002, p.1675. Sallee D, Spector ML, van Heeckeren DW, Patel CR. Primary pediatric cardiac tumors: a 17 year experience. Cardiol Young 1999;9:155-62. Marx GR, Bierman FZ, Matthews E, Williams R Two dimensional echocardiographic diagnosis ofintracardiac masses in infancy. JAm Coil Cardiol 1984;3:827-32. McAllister HA, Fenoglio JJ. Atlas of rumor pathology, second series: Tumors ofthe cardiovascular system. Armed Forces Institute ofPathology, Washington DC, 1978. Spooner EW, Farina MA, Shaher RM, Foster ED. Left ventricular rhabdomyoma causing subaortic stenosis - two dimensional echocardiographic appearance. Pediatr Cardiol 1982;2:67-71.
218
6
7 8
9 10
11 12 13
14
Arciniegas E, Hakim M, Farooki ZQ, Truccone JM, Green EW. Primary cardiac tumors in children. J Thorac Cardiovasc Surg 1980;79:782-91. Bini RM, Westaby S, Bargeron LM, Pacifico AD, Kirklin JW. Investigation and management of primary cardiac tumors in infants and children. JAm Coll Cardiol 1983;2:351-7. Gotlieb AI, Chan M, Palmer WH, Huang SN. Ventricular preexcitation syndrome. Accessory left atrioventricular connection and rhabdomyomatous fibers. Arch Pathol Lab Med 1977;101:4869. Mehta AV. Rhabdomyoma and ventricular preexcitation syndrome. A report oftwo cases and review ofthe literature. AmJDis Child 1993;147:669-71. Krasuski RA, Hesselson AB, Landolfo KP, Ellington KJ, Bashore TM. Cardiac rhabdomyoma in an adult patient presenting with ventricular arrhythmia. Chest2002;118:217-21. Ross BA, Crawford FA, Whitman V, Gillette PC. Atrial automatic ectopic tachycardia due to atrial tumour. Am HeartJ 1988;1 15: 606-10. Mas C, Penny DJ, Menahem S. Pre-excitation syndrome secondary to cardiac rhabdomyomas in tuberous sclerosis. J Paediatr Child Hcalth 2000;36:84-6. Van Hare GF, Phoon CF, Munkenbeck F, Patel CR, Fink DL, Silverman NH. Electrophysiologic study and radiofrequency ablation in patients with intracardiac tumours and accessory pathways: Is the tumour the pathway? J Cardiovasc Electrophysiol 1996;7:1204-10. Gatzoulis MA, Becker AE. Cardiac tumours. In Anderson RH, Baker EJ, Macartney FJ, Rigby ML, Shineboume EA, Tynan M (editors). Paediatric Cardiology 2nd Edition. Churchill Livingstone, London, 2002, p.1676.
Nethrimds Heart Jounal, Volume 14, Number 6, June 2006
Intracardiac rhabdomyomas producing
symptoms in infancy: the role
of
radiofrequency catheter ablation M. Emmel, K. Brockmeier, N. Sreeram
Background. Cardiac rhabdomyomas, although benign, may produce symptoms related to arrhythmia or mechanical obstruction. Surgical excision is the therapy of choice for symptomatic rhabdomyomas in infancy. Patients and Meods. Two infants with intracardiac rhabdomyomas producing symptoms underwent radiofequency catheter ablation of the tumour. In patient 1 the diagnosis of multiple rhabdomyomas associated with recurrent supraventricular tachyarrhytbmias and foetal hydrops was made in utero. After birth, several antiarrhythmic agents were adminstered, without successful suppression of the tachyarrhythmia. At seven months of age, the infant had one large residual tumour on the left atrial aspect ofthe anterior mitral valve leaflet with associated pre-excitation and re-entrant supraventricular tachyarrhythmia suggestive of a leftsided pathway. Catheter ablation of the accessory pathway was performed via a retrograde femoral arterial approach, targeting the earliest site of ventricular activation. Patient 2 presented as a neonate with multiple rhabdomyomas, one of which, measuring 15 mm x 15 mm, was producing severe mitral valve inflow obstruction resulting in symptoms of heart failure due to a large left-toright shunt at atrial level and persistent pulmonary hypertension. Via the femoral vein, a 5F ablation catheter was advanced across the atrial septum, and the tumour directly ablated. Results. Echocardiography performed 24 hours later demonstrated alteration in tumour morphology, with the development of a large central M. Emmel K. Brockmelr N. Smrwam Department of Paediatric Cardiology, University Hospital of Cologne, Cologne, Germany
Correspondence to: N. Sreeram Department of Paediatric Cardiology, University Hospital of Cologne, KerpenerstraRe 62, 50937 Cologne, Germany. E-mail: [email protected]
#C
Netherlands Heart Journal, Volume 14, Number 6, June 2006
echolucent area, followed by progressive tumour sbninkage in both infants. Patient 1 was disharged at 24 hours, and patient 2 at seven days postablation, without symptoms. Follow-up at four weeks confirmed further tumour shrinkage. Conclusion. Transcatheter tumour ablation may be beneficial in selected infants and children. (Neth HeartJ2006;14;215-18.)
Keywords: rhabdomyoma, ablation
Rhabdomyomas are the most frequent intracardiac tumours found in foetuses, infants and children, and occur almost exclusively in patients under the age of 15 years.' Their size may vary from a few millimetres to several centimetres. Tuberous sclerosis is present in over 50% of the patients found to have rhabdomyomas.2 Spontaneous regression of the tumour is possible, and has been well demonstrated by echocardiographic follow-up.3 The clinical profile is often dominated by signs oftuberous sclerosis. Occasionally, however, rhabdomyomas may be the immediate cause of morbidity or mortality, and in general the prognosis ofchildren with symptomatic rhabdomyoma is poor.4'5 The major cause ofsymptoms is intracavitay obstruction to blood flow, or the association with potentially lifethreatening arrhythmias.I Surgical excision has hitherto been recommended for symptomatic tumours. Complete removal however is not always possible.6'7 We report transcatheter ablation ofintracardiac rhabdomyomas producing symptoms in two infants.
Patlent I In this patient recurrent tachyarrhythmias with a 1:1 atrioventricular relationship suggestive of a re-entrant supraventricular tachycardia, associated with the development offoetal hydrops, was diagnosed in utero at 34 weeks of gestation. Echocardiography demonstrated multiple intracardiac rhabdomyomas. Following a trial of maternal digoxin therapy, the foetus was delivered at 38 weeks' gestation. Posmatally the infant had recurrent supraventricular tachycardia, associated with ventricular pre-excitation during sinus 215
_r- - - .-_ . . - . _.: .
Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation
.
;
6
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.
.. .
. * s
L. e
....
.......
. . . ;. . . . . ;. . .. . .,,,...-,.,; *.. ........... ,4 ,.4 vi.................................................
.......
.s.*................ , , " Fb*8 ..... ....... . .....'¢ lo @A. ._ .¢8........................................_1......-.;.... 1.
*@* :z*z lw .¢@ -,:o** .bs*. @e .4 .jas
vs.9w*t
i** ,,.,. .,- *
it
MI
::
.---
...
.*.
sw@v1 **s .S*** ****
+ *e**i
I
I .....
---
...
woe 6w*4 **J. 9*.o* tww
:
W4 W.,.. . .W!~ ~ ~ ~ ~ ~. . . .
#
e AS 4.
::
I.
..
...
.2
....... . .. ...t ........~~~~~~~~~~~~~~ ....._.....b88*|*s*__w__*__4 ~ _,.... .. _. .......... .. --!h-
Figure 1. Singk-kad ECG showing spontaneous termination of re-entrant supraventricular tachycardia in patient 1. 7'be sinm beats confirm maniftst ventricularpre-excitation.
rhythm (figure 1). Despite therapy with up to four antiarrhythmic agents (digoxin, propranolol, propafenone and amiodarone in various combinations) the infant continued to have episodes of tachyarrhythmia with signs ofmfld dflated cardiomyopathy, presumed to be due to the tachyarrhythmia. At seven months of age, only one large rhabdomyoma was present, in the left
AV groove on the left atrial aspect ofthe anterior leaflet ofthe n-iitral valve.
obtained, an invasive electrophysiology study was perfonned to ablate the accessory pathway. Under general anaesthesia, a 5F ablation catheter (Marinr, Medtronic) was advanced retrogradely via the femoral artery into the left ventricle.
After informed
symptoms.
consent was
retrograde atrial activation during tachyarrhythmia, and earhest ventricular activation in sinus rhythm were localised to the anterior aspect ofthe left AV groove. Defivery of radiofrequency energy to this site resulted in abolition of pre-excitation, and noninducibility of tachyarrhythmia. The catheter ablation procedure was guided entirely by intracardiac electrical Earliest
recordings, with no attention being paid to the relation of the accessory pathway to the location of the tumour. Echocardiography performed 24 hours later demonstrated a morphological change in the tumour, with a central area of echolucency suggestive of hquefaction necrosis (figures 2A and 2B). Follow-up echocardiography demonstrated further tumour shrinkage associated with scar formation (figure 2C). At eight months of foHow-up the patient has remained without Patient 2 In patient 2 multiple intracardiac rhabdomyomas were diagnosed in utero. After spontaneous defivery (birth weight 2.9 kg), the patient developed signs of heart failure associated with a large tumour in the left atrium
severe mitral inflow obstruction. The resulted in a large left-to-right shunt via the foramen ovale, associated with persistent pulmonary of hypertension. As an altemative to surgical resection the tumourl, catheter ablation was undertaken at two weeks of age.
producing tumour
-----------
MM....
.=
-.W
MWAMMO-1-
.1
..I
Figure 2A. Echoeardiograpbk appearance Figure 2B. Tumour appearance 24 hours Figure 2C Tumour appearance sixweeks after of the tumour, in the parasternal longs-axis after ablation, demonstrating a eentral ablation. 7'be tumour bas sbrunkfurOver, and the eebolueeney is repl"ed by an irregular eekolueent area. projeetion, prior to catheter ablation. echodense mass suggesting tumour zart4ng. 216
Nethcrlands Hcart Joumal, Volume 14, Number 6, junc 2006
qc
Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation
Figure3A Transophagelechocardiogram Figure 3B. Tumour appearance 24 hours Figure 3C. Tumour appearance four weeks demonstrating the kft atial tumour in pa- after ablation, showing the developmnt ofa afterablation, showinga similarsequence of tient 2, which appears to obstruct the mitral central echolucent area. morphological changes as in patient 1. valve.
Under transoesophageal echocardiographic guidance, a 5F ablation catheter was advanced from the femoral vein across the atrial septum. Good contact with the tumour was confirmed by a combination of echocardiography and the local electrical signals from the tumour, which appear as fast conducting, myocardial signals not different from normal atrial electrograms. A total of45 lesions (a lesion was defined as application of radiofrequency current to reach a temperature of 60 °C for 60 seconds) were applied directly to the tumour. There were no procedure-related complications. Within 48 hours of ablation, the tumour showed similar morphological changes as in patient 1, with improved mitral valve inflow and relief of symptoms (figures 3A and 3B). The infant was discharged from hospital at seven days after ablation, and anticongestive medications were discontinued at 14 days. At four weeks of follow-up the tumour had shrunk further, associated with scar formation (figure 3C).
Discussion Rhabdomyomas are the commonest form of intracardiac tumours, and the majority are diagnosed within the first year of life.2 The association between intracardiac tumours and arrhythmias has been well recognised, and direct electrophysiological data suggesting that the tumour is indeed the source of the arrhythmia have been offered in individual case reports.8-'0 Ross et al. described a child with atrial ectopic tachycardia, in whom surgical removal of a right atrial rhabdomyoma was associated with resolution of tachyarrhythmia." Mas et al. described a neonate presenting with recurrent atrioventricular tachycardia and multiple rhabdomyomas, in whom spontaneous regression of the rhabdomyomas was associated with loss of ventricular pre-excitation and freedom from symptoms.12 Van Hare et al. reported catheter ablation in the vicinity of the tumour (visualised by echocardiographic demonstration ofthe Netherlands Heart Journal, Volume 14, Number 6, June 2006
proximity of the ablation catheter to the tumour), which cured the tachyarrhythmia.'3 In the first patient described here, placement of discrete endocardial lesions on the ventricular aspect of the mitral valve resulted in loss of pre-excitation, with associated changes in tumour morphology, providing electrical and morphological evidence ofthe tumour itselfbeing the accessory pathway. Considering a discrete RF lesion at the site ofearliest ventricular electrical breakthrough resulted in both loss ofventricular pre-excitation and associated changes in the structure ofthe tumour, the most likely explanation is that the tumour itself, by straddling the atrioventricular groove, was functionally the accessory atrioventricular pathway. Based on the observation that tumour reduction could be achieved by direct application of radiofrequency current, we proceeded to directly target the tumour for ablation in patient 2, with a view to reducing the tumour mass and relieving symptoms of mitral valve obstruction. While a theoretical risk of tumour embolisation cannot completely be excluded, the tumour had all the echocardiographic characteristics of myocardial tissue, and was in this respect not comparable with a myxoma, which is more likely to result in systemic thromboembolic complications.'4 Rhabdomyomas, on the contrary, although not malignant tumours are more likely to cause symptoms related directly to tumour bulk, and the resulting intracavitary obstruction. To our knowledge, spontaneous embolisation of a rhabdomyoma has not previously been described. Additionally, there is a wealth ofexperience with catheter ablation of left atrial or left ventricular myocardium in adults and children with a wide variety of arrhythmias. These procedures are also not associated with a long-term risk of thromboembolic complications when antiplatelet drug therapy is routinely administered following ablation procedures. In view of these prior observations, catheter ablation of the tumour was felt to be justified. The catheter approach was facilitated by the presence 217
Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation
of a large interatrial communication, providing access to the tumour from the femoral vein. Although no immediate reduction in tumour size was noted', a similar sequence of echocardiographic changes as observed in patient 1 was also seen in patient 2, with reduction in tumour bulk accompanying relief of symptoms, allowing cessation of pharmacological antifiilure therapy. These preliminary data suggest a role for radiofrequency catheter ablation as an alternative to surgery for treatment of symptomatic intracardiac tumours. E References 1
2
3 4
5
Gatzoulis MA, Becker AE. Cardiac tumours. In Anderson RH, Baker EJ, Macartney FJ, Rigby ML, Shinebourne EA, Tynan M (editors). Paediatric Cardiology 2"d Edition. Churchill Livingstone, London, 2002, p.1675. Sallee D, Spector ML, van Heeckeren DW, Patel CR. Primary pediatric cardiac tumors: a 17 year experience. Cardiol Young 1999;9:155-62. Marx GR, Bierman FZ, Matthews E, Williams R Two dimensional echocardiographic diagnosis ofintracardiac masses in infancy. JAm Coil Cardiol 1984;3:827-32. McAllister HA, Fenoglio JJ. Atlas of rumor pathology, second series: Tumors ofthe cardiovascular system. Armed Forces Institute ofPathology, Washington DC, 1978. Spooner EW, Farina MA, Shaher RM, Foster ED. Left ventricular rhabdomyoma causing subaortic stenosis - two dimensional echocardiographic appearance. Pediatr Cardiol 1982;2:67-71.
218
6
7 8
9 10
11 12 13
14
Arciniegas E, Hakim M, Farooki ZQ, Truccone JM, Green EW. Primary cardiac tumors in children. J Thorac Cardiovasc Surg 1980;79:782-91. Bini RM, Westaby S, Bargeron LM, Pacifico AD, Kirklin JW. Investigation and management of primary cardiac tumors in infants and children. JAm Coll Cardiol 1983;2:351-7. Gotlieb AI, Chan M, Palmer WH, Huang SN. Ventricular preexcitation syndrome. Accessory left atrioventricular connection and rhabdomyomatous fibers. Arch Pathol Lab Med 1977;101:4869. Mehta AV. Rhabdomyoma and ventricular preexcitation syndrome. A report oftwo cases and review ofthe literature. AmJDis Child 1993;147:669-71. Krasuski RA, Hesselson AB, Landolfo KP, Ellington KJ, Bashore TM. Cardiac rhabdomyoma in an adult patient presenting with ventricular arrhythmia. Chest2002;118:217-21. Ross BA, Crawford FA, Whitman V, Gillette PC. Atrial automatic ectopic tachycardia due to atrial tumour. Am HeartJ 1988;1 15: 606-10. Mas C, Penny DJ, Menahem S. Pre-excitation syndrome secondary to cardiac rhabdomyomas in tuberous sclerosis. J Paediatr Child Hcalth 2000;36:84-6. Van Hare GF, Phoon CF, Munkenbeck F, Patel CR, Fink DL, Silverman NH. Electrophysiologic study and radiofrequency ablation in patients with intracardiac tumours and accessory pathways: Is the tumour the pathway? J Cardiovasc Electrophysiol 1996;7:1204-10. Gatzoulis MA, Becker AE. Cardiac tumours. In Anderson RH, Baker EJ, Macartney FJ, Rigby ML, Shineboume EA, Tynan M (editors). Paediatric Cardiology 2nd Edition. Churchill Livingstone, London, 2002, p.1676.
Nethrimds Heart Jounal, Volume 14, Number 6, June 2006
