hello there! Shaking chills is not just the low glucose. it can be UTI , psychiatric, anxiety as Generalized Anxiety Disorders and Stress/ Depression are very common etiologic factor for these chills at any age. Chills are body s response by hypothalamus ( temperature centers) to keep the temperature at constant 98.6 Degree Fahrenheit. A lot of things mess with that thermostat resulting in chills and rigors and fever etc. And they need to be sorted outand for that it would be better to have some work up as age of 65 with pacemaker and blood thinners and Respiratory tract infection and wheezing etc all make you very vulnerable to many etiologies that can result in chills. Systemic infections , Renal infections and immuno compromise status and hypothermia due to advanced age and Drug hypersensitivity and High grade fevers irrespective of the cause are all the possibilities. So i recommend to seek help. Visit near by ER and Let them help you. once all pathologies are ruled out You need to have psychiatric assistance and some rehabilitation programs and some group therapies would be of help to manage the anxiety and i am sure you will be fine. Meanwhile stay in touch with your cardiologist and have keen eye on your blood profile to avoid bleeding diathesis and have regular follow ups in that regard. Good Luck And i hope i was of some help. Cheers S Khan