Sudden death and defibrillators

[Doly__0]

  My 8 year old son has Hypertrophic Obstructive Cardiomyopathy and had a septal myectomy 2 years ago. His septum still remains massively hypertrophied at 23mm. He also has prolonged QT's and a repolarization abnormality, among all the other complications with HOCM. We recentley left our clinic and moved to a new one searching for some hope. The pediatric cardiologist we see now was also the pc for my nephew, who had HOCM and who died at the age of 7, from sudden death. After many tests and our pc meeting with other specialists, we were told our son is at high risk for sudden death at any time (like our nephew). We were also told the only thing left to do for our son is to put in an implantable defibrillator, and this holds no promises for success when his heart goes into arrhythmia. He also said if we choose to do this we would be trading one problem for another. After thinking this conversation over, I am completely confused by this comment. What would be the disadvantages to having a defibrillator implanted if this is his last hope anyway?? Any comments you have would be GREATLY appreciated!!

[CCF Cardio MD - MTR]

Dear Dolly, thank you for your question.  I visited the website you designed
for your son Andrew and it helped me to understand his disease and the impact
it has had on his life and on your family.  I understand your frustration with
the current situation and I think I can help.  You seem to know a lot about HCM
and you have correctly ascertained that most treatments are palliative and that
the juvenile form of HCM is particularly aggressive.  HCM is caused by a
genetic defect in the myocardial muscle proteins that causes disordered muscle
growth.  The resulting manifestations are obstruction to outflow from the
left ventricle and arrhythmias.  The septal myectomy temporarily improved
the situation for your son, but his septal obstruction has obviously returned
and other problems seem to have arisen.  I'm not sure what's causing his sweating
and fever spells currently.  The implantable defibrillator sounds like the next
step but I'm unable to tell you what the success of this device would be in
responding to a lethal arrhythmia.  Defibrillators continuously monitor the
heart rhythm via an internal lead that is implanted in the right ventricle.
When a sustained ventricular arrhythmia develops (which can quickly cause loss
of consciousness and hemodynamic deterioration in a patient with HCM), the
defibrillator responds by trying to overdrive pace the rhythm into termination
or by delivering an internal shock to terminate the arrhythmia.  Defibrillator
technology has improved greatly in the last five years and the battery now can
be implanted under the collarbone much like a pacemaker.  I can't tell you
whether this is the best treatment for your son at this point, but we have
many excellent pediatric cardiologists here at Cleveland Clinic who are very
experienced with treating children with HCM.  Dr. Douglas Moodie (216-444-6717)
or Dr. Daniel Murphy (216-444-9393) are both experienced with HCM and would
be happy to evaluate your son.  Implantable defibrillators and cardiac transplantation
are both common procedures here so I think we definitely could help your son if
you are able to bring him here for an evaluation.  If you do decide to come
for an appointment, we would need detailed copies of his medical records, echo
tapes, cardiac catheterization films, x-rays, etc.  I hope you find this information
useful and please write back with any additional information or questions.
Information provided in the heart forum is for general purposes only.  Specific
diagnoses and therapies can only be provided by your physician.