Ask a Neurologist. Get Answers to Your Neurology Questions.
Hello from JustAnswer.
Yes, the muscle atrophy and fasciculations would likely be due to the carpal tunnel syndrome. If there are no symptoms affecting muscles elsewhere on the body, then there is no reason to suspect another condition.
If there is muscle atrophy of the muscles of the thenar eminence, then there would be more impetus to be treating the carpal tunnel syndrome more aggressively. You do not say how it is being treated currently, but you should contact your doctor for consideration of additional treatment.