subaortic membrane

My daughter had a resection of subaortic membrane in 2/09. We just went for her yearly check-up and found out that it is already growing back.  Last year her pressure was 3.0 and now it's 3.7. She has complex CHD that includes: dexttracardia, pacemaker, s/p repair ASD and VSD, s/p repair mitral and triscupid valve. My question is why is it growing back so quickly?  I must add that they couldn't resect it all because of the anatomy of her heart.

[Marie M Gleason, M.D.]

I am not sure what you mean by  a "pressure" of 3.0 and 3.7.   is that the measurement of the membrane in millimeters, or the actual pressure gradient in mmHG?  or is it the speed of the blood flow across the outflow tract (measured in meters/second)?  About 15% of subaortic membranes grow back, and if it is not able to be fully resected at the first operation, then one expect that to be even a higher chance of recurrence.  Sometimes the patient's anatomy does dictate the success of a resection alone.  In some circumstances where the outflow tract is small, in addition to the subaortic membrane, then a bigger operation called a Konno procedure needs to be done.  In this operation the entire outflow tract is enlarged, making it unlikely that a membrane will recur.  Soemtimes the aortic valve needs to be replaced at the time of surgery.  You should speak with your cardiologist to determine what they feel are your child's risk factors for this issue, and whether a Konno operation might be an option in the future.