I would go for MRIs. Some surgeons and cardios prefer CTs as that is what they are used to for years. My cardio wants regular echos then I frequent scans, but I have not talked about MRIs yet as I have 8 more months before next scan.I’ve had this same question. I had surgery in April 2015 at age 41 (almost 42) and have an aortic mechanical valve conduit. My surgeon wants ct scans every 2 years. However, I am guessing his average patent is much older. I went for the first “2 year post-op” ct scan in 2017, but didn’t go last year. I am very concerned about the radiation, as I had two pre-op (heart and brain) ct scans and one ct scan 6 weeks post op, so I have now had four (and it will cost me almost 6,000 or 7,000 for the ct scan, until I hit my crazy deductible). I see my cardiologist every year and occasionally have echos. I have had a few echos, but I think my cardiologist generally does them every ten years. My surgeon agreed I could go for a ct scan every three years so I will have less radiation exposure (so next year) but I’m not sure I want to go. Each scan is with contrast. Not sure if it matters but I’m only 4 ft 10 and 100 lbs and I doubt they adjust for my kid-like size when dosing. I’m sorry I am no help, but I am interested in the responses you receive.