Let me preface this by saying I'm a medical practitioner, and I read the story
He has a written report of he cardiac ultrasound, and he has a written report of it. The data he wants are the 'still images' of his ultrasound. An ultrasound is a live, dynamic test that looks at the heart as it moves, its not like an xray or CT where a single image gives you the data you want. While single images are often recorded (mostly medico-legially I believe), at the end of the day, he wants to compare some still images from his cardiac ultrasound taken 10 years ago to the images taken recently. Not worth doing, exceeding rare that 'any' useful comparison could be made.
I agree there is no need to store TB's of data for ultrasounds, though the fact that they still have it is interesting in itself!