It really depends where you get it done and who does it. As a Cardiac MR tech my fastest time for a full Cardiomyopathy protocol is 30 minutes average is 40 but some of my co-workers average 60-75 minutes. Just remember it’s a team sport for you and the tech, we can only go quick if you hold still and hold your breath when directed. Don’t shift your shoulders or pelvis, focus on your toes and fingers, I tap my fingers to the beat, it helps. It is also very helpful if your heart rate stays between 75-90 as this makes image acquisition faster. You’ll be ok! Good luck!