I have a marked enlarged heart since 2010 and had it checked out normal heart cath normal stress test normal ecg I have hypertension. Doc not worried?

I would look further. You are young and have signs of an enlarged heart. I would be aggressive and I would want to see and echo report and make sure you do not have sleep apnea . Your blood pressure should be very well controlled by maximizing lifestyle: nutrition to lower, exercise, stress relief, great sleep. Stay on top of this, ok?