Your concern for health is quite justified as strong family history of cardiac disease,along with your borother also got coronary blockages, you are also having risk factors Hypertension
,Dyslipedemia, and over weight and age 59 years male.
It is good that you donot smoke and your stress test
was normal 10 years back. OK
This would be pertinent to know do you get chest pain
while walking or climbing up hill or stairs Wich could be Angina Pectoris
, if there is no Angina you can weight in the mean time just check up with your Physician,Keep your BP and Lipids under control and add Asprin for prevention if required?
If you are worried too much you can get CT Angiogram of coronary artery
along with calcium score which will be very useful to know state of your coronary arteries blockage if any
I wish you good luck