TRANSPOSITION AND DILATATION OF AORTIC SINUSES

My son is 14 years old. He had Transposition of great arteries and had arterial switch operation at one month of age. He has been able to participate in all sports unlimited until last year when we discovered that his aortic sinuses has enlarged. He is about 180 cm tall and about 68 kg. This is part of the last diagnosis we had. Blood pressure 127/67, pulses normal throughout, cardiac auscultation unremarkable. ECG showed sinus rhythm ant a rate of 62/minute with PR interval that is slightly long at just over 200 ms. There is a relatively narrow partial right bundle branch block pattern. Voltages are not particularly suggestive of hypertrophy although there are prominent voltages across the midprecordial leads as we would often see in slim patients this age.
The main reason for though consultation was to discuss further the finding of marked aortic root dilatation on MRI with peak measurement of approximately. 46mm. He also had a recent ECHO which showed peak measurement of 39mm which is little changed from last ECHO that measured 38 mm.

My question is why the peak measurements between MRI are and ECHO are so different and which are more accurate. Also I would like to know if you know of any other patient post TGA repair with similar problem. What are the risks for my son if he participates in soccer games and other sports at high school? Thank you for the answers.

[sam1962]

My son, now 5, was born with TGA and had his ASO @ 2 days old.  He also has "significant" aortic root dialation which is being watched.  As I understand things, it is very common for this to happen after the ASO but in 75% of the cases, it dialates, reached a max point and then never progresses, but there are cased, like our sons, where it just keeps getting bigger and will at some point require medical intervention.  According to Childrens Heart Foundation, Boston MA, they are not sure why this happens with some people and not others.

Not much help when it is your child you are worring about!?!