Is this an ascending aortic aneurysm? How was the dilation found? CT or echo? If the first test was a CT and now the second CT test indicates it has gone from 3.9 to 4.3, the rate of growth is about .4 centimeters in a year. In another 12 months, it might continue to grow at that same rate which would bring you to 4.7 which is still well below the size at which surgery is recommended. I think that is what your cardiologist is thinking.

You should be careful with lifting or anything else that might put a strain on you. My cardio recommends I not lift more than 25 lbs.

I think you would be wise to make a telemedicine appointment with your cardio to ask for more information and guidance. And you can also ask if you could have an echo in 6 months if that would give you comfort. The echo and CT measurements are done differently but your cardio should be able to interpret the results to see if the dilation is growing at an alarming rate. I am 75 and I have an echo every 6 months and a CT every couple of years. No radiation with the echo so if it continues to grow slowly, I'm OK with the echo monitoring.

I wish you good luck. I think you have no reason for panic at the moment but you can always get a second opinion from another cardio.