@professorkrh ......at 3.4cm your doctor can be unconcerned, but given your family history, as stated, you should be on guard for changes to the size, or number of aneurysms that may appear. At the very least, become as informed as possible about aneurysms, who you'll go to for treatment and support when needed, and maintain continued regular monitoring by a cardiologist with aneurysm expertise, and understanding of familial aneurysm issues. Maintain a healthy lifestyle and keep your blood pressure at low normal level. If possible, establish a relationship with a high volume aortic center that can provide all support neccessary when needed. Knowledge is power and will allow you to keep this circumstance in manageable perspective. Best wishes!!