@bryanfox Hi Bryan, Oh, I know what you are feeling and the fear and trepidation that the end is near. I've had the same diagnosis as you since 2007 and it was about 3.9 at diagnosis and now is about 4.2. My suggested limitation on lifting weights is 25 lbs. And that is to assure the aneurysm size doesn't enlarge. At the size of 4.3, the approach is to wait and watch. You are on a beta blocker so the pressure on the artery is controlled. I was told to continue with my daily cardio exercise on a strider which is similar to the elliptical but not to exert myself so that I am unable to carry on a conversation while exercising. The beta blocker keeps your blood pressure controlled and is kind of self limiting as it keeps your heart rate low.
You will likely be monitored every 6 months with an echocardiogram and every 2 or 3 years with a CT scan. Be aware that the measurements of these two tests are different. One measures on the bias and the other measures straight across. Also be aware that the technician doing the test can see the measurement differently. So, don't panic if the measurement increases a point or two as the aneurysm itself may not have changed size.
My advice is to follow your cardio's direction on limiting lifting, keep exercising, limit saturated fats and sugars, lose weight if that is an issue and if you smoke, it is imperative that you quit — immediately. And all of that said, Enjoy your life. This aneurysm, with proper treatment may never enlarge to the point of needing repair. And if it does grow, as much as none of us wants surgery, repair can be done.
What a shame it would be if having this aneurysm stole your enjoyment of life. Have fun, make plans and don't be consumed with unnecessary worry.