My husband had a heart attack at age 45, followed by quadruple bypass surgery. At age 52 he required both hips be replaced and at age 58 and again at 61 he required angioplasti with stents because of continuing CAD. He is also diabetic. We in Ontario Canada are covered by the Ontario Health Insurance Plan and all of these procedures were covered by the plan with no cost to us. We are required to pay for drugs however fortunately we have an extended health plan from my former work that covers 80% of the cost and now that I am over 65, OHIP covers all the cost for my drugs also. I cannot imagine what our life would have been like without OHIP but I suspect my husband would not have survived.
There are indeed sometimes wait times for elective surgeries (we have never experienced any) but I have never heard of anyone having to wait for life saving or emergency surgery.