A Broken Heart

Incidence:
35,000 children are born with heart defects every year (American Heart Association)
Only 1% of those children have truncus arteriosus (many sources, including the Herma Heart Center where Turnip may be treated)
That means about 350 babies are born in the U.S. with the same condition as Turnip every year. (330 according to the Morbidity and Mortality Weekly Report from jan 6, 2006)
Treatment:
Surgery usually happens at 6-12 weeks (EPA, page 4)
15-50% of children require another surgery within the next five years (i.b.i.d.)
All heart valves are replaced after 12 years(i.b.i.d.)
Newborns with truncus arteriosus stayed in the hospital for an average of 30 days during 2003 (CDC, table 2)
The hospital charges for this stay (not including lab tests and doctor fees) ran to $200,000 (CDC, table 2)
Mortality:
In a small study published in 1996, 6% of infants died before surgery and 10% died during surgery (EPA, page 4)
In a national survey, 20% of newborns with truncus arteriosus died in the hospital in 2003 (CDC, table 1)

Monday, March 28, 2011

Calvin's tulips






The tulips we planted in Calvin's honor quite some time back are finally pushing through the dirt.  They didn't do so well last year-- I think it was either the rabbits or a lack of water or sun. So, this year, I have pushed the big barrel out from under our overhang.  At least I can control their access to sunlight and water, if not the appetites of the bunnies.

Friday, March 25, 2011

Oliver's doctors

Today, Oliver graduated from another medical service.  For the past two years, we have been making semi-annual pilgrimages back to Milwaukee to see their developmental team.  We had another appointment scheduled for Monday.  However, our insurance denied coverage for the appointment.  When we called the Herma Heart Center, they confirmed that as Oliver was doing so well as of his last check at their developmental clinic, there is really no reason for him to continue to receive evaluations.  Now, we are down to:

1) a pediatrician
2) a cardiologist
3) a surgical team

Oliver sees the pediatrician with the same frequency as any other kid.  He sees his cardiologist every six months.  Hopefully, he won't see his surgical team again for many years. 

Friday, March 18, 2011

what went wrong

This semester I am teaching Zoology at a local college.  Next week we will start our unit on development.  Consequently, for the past few weeks, I have been updating my understanding of how animals (including humans) develop.

On page 389 of Scott Gilbert's Developmental Biology textbook, there is a picture of what went wrong with Oliver's heart.   I can't stop looking at it.  You see, during development, human hearts go through a stage where there is only one outflow vessel from the heart: the truncus arteriosus.  This is a normal stage of development.

In normal development, that common vessel will eventually divide in half and give rise to the aorta and the pulmonary trunk.  In Oliver, and in other children with Truncus Arteriosus, that common trunk, or truncus arteriosus, does not divide in half.  For some reason, the cells that usually separate that common trunk into two vessels do not migrate into their proper place and divide the single tube in two--and so, the developing embryo is left with a single outflow vessel: the persistent truncus arteriosus. 

This process is similar in many other animals, and has been studied in chickens.  In the enlarged image, you can see the cardiac nerual crest cells migrating to the conotruncus, a.k.a. truncus arteriosus, of a chick embryo where they will form an internal dividing wall to create the separate aorta and pulmonary trunk.  For some reason, this did not happen in Oliver.  And it sucks.