[ARVD-FORUM] question - Management of recurrent VT in a 9 month old Dr. Levine

[ARVD Symposium]

English - Spanish

There are multiple technical challenges with respect to ICD therapy in a 9
month old.  If drugs are effective, that would be the approach that I
prefer.  If VT breaks through the pharmacologic therapy and the recurrent VT
is monomorphic with a consistent morphology for each episode, I would
consider an ablation procedure, (RF, cryo, microwave depending on what might
be most readily available) fully realizing that if this is ARVD or some
other cardiomyopathy, VT may occur in the future from a different focus.
One might also consider a surgical disconnection of the RV if that is where
the tachycardia is arising from so that the VT does not conduct to and
recruit the LV.

However, IF device therapy is the only option with the others having been
tried and failed or tried and not totally effective, then consider the
following:

Use the Medtronic 4968 epicardial bipolar sew-on lead for sensing and
pacing.  This is a steroid eluting epicardial lead.   One should also aim to
place in on the LV, particularly if the RV is being replaced by fatty or
fibrotic tissue.

No company still manufactures epicardial patches and even if these were
available, they would be too large for a 9 month old heart.  Also, the
standard endocardial leads would be too large for a 9 month old venous
system AND the coil would be too long for an infant heart.  Thus, consider
tunneling a Sub Q Array to a posterior position, behind the LV.  Medtronic
makes a single coil array that should be effective. SJM manufactures an SVC
coil that should also work.

An active can should be utilized and placed in the upper RIGHT abdomen. The
shock vector will be LV to Can with the SVC port plugged.  This will also
encompass the RV if that is the locus for the VT.

Additional considerations:
-Over the next several years you will, hopefully, have a very active toddler
-Implantation of the leads should have slack for growth and no sharp bends
in them.

*Device: Medtronic's shape is NOT conducive as the corners are too sharp.
It tends to be rectangular.
-St. Jude and Guidant have the best shapes.
-St. Jude has the most programming options as far as programmable tilt,
pulse width of each phase of biphasic shock, sensing with threshold start
and decay delay which would be a huge advantage for this type of situation
where there are so many unknowns.

Paul A. Levine, M.D., FACC
Vice President, Medical Services
St. Jude Medical CRMD

-------------------------------

Hay multiples desafios tecnicos con respecto a la terapia con CDI en un bebe
de 9 meses. Si las drogas son efectivas, ese seria el enfoque que yo
preferiria. Si la TV vence a la terapia farmacologica y la TV recurrente es
monomorfica con una morfologia consistente para cada episodio, yo
consideraria una ablacion (por RF, crio, microondas, dependiendo de lo que
pueda estar disponible mas rapido) comprendiendo totalmente que si esto es
DAVD o alguna otra miocardiopatia, la TV puede ocurrir en el futuro en un
foco diferente. Uno tambien podria considerar una desconexion quirurgica del
VD si alli es donde la taquicardia se origina, de manera que la TV no se
conduzca e incorpore el VI.

Sin embargo, SI la terapia con el dispositivo es la unica opcion, una vez
que las otras se han intentado y han fracasado, o se han intentado y no son
totalmente efectivas, entonces considere lo siguiente:

Emplee el Medtronic 4968 con electrodo epicardico bipolar "pegado" (sew-on)
para el sensado y la estimulacion. Este es un electrodo epicardico que
emplea esteroides. Uno debe tambien intentar colocarlo en el VI,
especialmente si el VD esta siendo reemplazado por tedijo adiposo o fibroso.

Ninguna empresa fabrica aun "parches" epicardicos e incluso si estuvieran
disponibles, serian demasiado grandes para un corazon de 9 meses. Ademas,
los electrodos endocardicos estandar serian demasiado grandes para un
sistema venoso de 9 meses Y el electrodo seria demasiado largo para el
corazon del ninio. De este modo, considere hacer pasar un modelo Sub-Q-Array
hasta una posicion posterior, detrás del VI. Medtronic fabrica un
dispositivo con un electrodo unico que deberia ser efectivo. SJM fabrica un
electrodo de la VCS que tambien deberia funcionar.

Deberia emplearse una caja activa y colocarse en el abdomen superior
DERECHO. El vector de descarga ira del VI a la Caja con el puerto de la VCS
conectado. Esto tambien abarcara el VD si ese es el sitio de la TV.

Consideraciones adicionales:
-	Durante muchos anios por venir tendra, esperemos, un ninio muy activo.
-	El implante de los electrodos debera dejar espacio para el crecimiento y
no debera presentar dobleces agudos.

*Dispositivo: El formato de Medtronic NO sirve puesto que las esquinas son
muy agudas. Tiende a ser rectangular.
-	St. Jude y Guidant tienen los mejores formatos.
-	St. Jude tiene mas opciones de programacion en cuanto a "tilt"
programable, amplitud de pulso de cada fase de la descarga bifasica, sensado
con comienzo de umbral y retraso en decaimiento, que serian una enorme
ventaja para este tipo de situacion, en la que hay tanto que se desconoce.

Paul A. Levine, M.D., FACC
Vice President, Medical Services
St. Jude Medical CRMD


-----Original Message-----
From: arvd-forum-bounces at ishne.org [mailto:arvd-forum-bounces at ishne.org] On
Behalf Of ARVD Symposium
Sent: 03 June, 2005 13:46
To: arvd-forum at arvd-symposium.org
Subject: [ARVD-FORUM] question Dr. Mesquita de Oliveira

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English - Portuguese

Good afternoon! This case is most difficult since the baby has only 9
months. Do you have an ICD available for this age? Would you place it by
thoraco-abdominal via?
If he was responsive to this association (propranolol + propafenone), I
would maintain him with this. If he doesn't respond to this association, I
would give him amiodarone + sotalol (that would strengthen the effect by
amiodarone). Anyway, if an ICD was feasible, I would indicate it!!
Warm regards,
   Dr Eduardo Mesquita de Oliveira(Cardiologista do Hospital Israelita
Albert Einstein-São Paulo-Brasil)

-------------------------------

Boa tarde!  Dificilimo o caso pois tem somente 9 meses.Tem CDI para essa
idade? A colocação é via toracoabdominal?
Se respondeu a essa associação(propranolol+ propafenona) manteria assim.Caso
nao respondesse a essa associação,daria Amiodarona+ sotalol(que
potencializaria o efeito da amiodarona).De qq forma se fosse possivel um CDI
,eu indicaria!!  Grande abraço  Obrigado
   Dr Eduardo Mesquita de Oliveira(Cardiologista do Hospital Israelita
Albert Einstein-São Paulo-Brasil)