Zachy's Heart Revisited

We have been getting a lot of questions about Zachary's upcoming surgery, so I thought I would dedicate a post to explaining about his heart condition as best I can.

I still remember the puzzled look on the ultrasound tech's face as she performed a fetal echocardiogram on my pregnant belly.  Zachy's cardiologist, Dr. Battiste, sat alongside her, trying to make sense out of his special little heart and arrive at a diagnosis.  When the test was complete, Steve bravely asked the tech how often she sees this condition on unborn babies.  The tech took a deep sigh, thought for a while, and admitted, "Like this?  Gosh, I do these fetal echos all the time, and it's probably been... five years!"  Needless to say, Zachy has some pretty unique anatomy.

The University of Michigan Hospital diagnosed Zachy with Double Inlet Left Ventricle, Tricuspid Atresia, Levo Transposition of the Great Arteries, and Atrial Septal Defect.  Easier said, he is missing his right ventricle, the chamber of his heart that pumps blood to his lungs.  Click here for a description and diagram of his heart prior to his Hemi-Fontan surgery last summer.

The following diagram gives some idea of what Zachy's heart looks like now, after his Hemi-Fontan (or Glenn procedure.)  This was the first of two surgeries to reduce the workload on his only effective pumping chamber, the left ventricle.  In this surgery, the deoxygenated blood returning from the top of his body via the superior vena cava was re-directed to bypass his heart and flow directly (and passively) to his lungs.

In this operation, the superior vena cava (1) is cut and both ends are sewn into the right pulmonary artery. Now blue blood returning from the upper body flows directly to the lungs (bypassing the heart). A patch is placed over the top part of the heart’s right upper chamber (3). This prevents blood from the upper body from entering the heart and blood from the lower body from entering the lungs. It also maintains a connection that is used for the final stage of the repair and greatly simplifies the last operation. [Zachary does not have the shunt labeled as (2), and the PA band from his first surgery was removed.]


Right now, Zachy's blue and red blood is still mixing, which results in a lower-than-normal oxygen saturation of about 80%.  This is why he sometimes appears "blue", especially around the lips or in his nail beds.  This is also why we have to watch him very closely when he comes down with a respiratory infection; it doesn't take much for his O2 sats to dip to dangerously low levels.  He handles colds much better these days, but prior to his Hemi-Fontan he ended up in the hospital three times for this reason.

I have linked to these videos before, but I would encourage you to revisit them.  Children's Hospital of Philadelphia is another leading center for surgery for pediatric single ventricle repair, and provides a series of videos to better explain these procedures.  The first half of this video gives a good explanation of the normal heart:  What Are Single Ventricle Malformations?  This video explains what happened in Zachy's surgery last summer:  The Hemi-Fontan Operation.  (See the mommy sobbing when they hand their baby off to the surgeons?  That's me.)

In a future post, I will explain the final stage of repair, the Fontan procedure, that Zachy will undergo in just two short weeks.

PLEASE start spreading the word and asking for prayers for our little man.  Also keep little Miguel in your prayers.  He is one of Zachy's friends that was having his Hemi-Fontan up at the U of M when Zachy was born, and he, too, is back for his Fontan procedure this week.