What can you do for someone who is having a heart attack before the ambulance gets there?

Rest + aspirin. Try to keep them calm- have them lie down. If you have an aspirin, have them chew and swallow it as Aspirin is probably the single most effective way to treat a heart attack and is very safe.
Give them an aspirin. Have then chew a full dose of aspirin, have them lay down, and keep calm.

Related Questions

How can I help someone who is suffering from a heart attack until the ambulance arrives?

You keep calm. Is the first suggestion. Help them stay calm--sit/relax, focus on breathing. If they have aspirin or nitroglycerin they are supposed to use, you can assist them with it--don't supply it if not, the Paramedics will handle that. If in a complex location, have someone outside to guide medics in. Nothing to eat or drink.

If someone is on viagra (sildenafil) they cannot take nitroglycerin. So what would be given in an ambulance to a heart attack patient who regularly takes viagra (sildenafil)?

No easy answer. Based on BP and how frequent the patient is monitored and how active the chest pain. The key is drop in BP and that may cause more harm, Also viagra (sildenafil) has a short half-life, so if the patient took if many hours prior, and has a stable BP, NTG is an option, and then there is a hypertensive patient, NTG may be beneficial to get the BP down and decrease workload.

My gma (85yrs) was diagnosed with a-fib. Could she have a heart attack? Do we need to do cpr or use a defibrillator while waiting for an ambulance?

Abnormal heart beat. Your grandmother has an abnormal heart beat. It could increase her risk for stroke. She may be a candidate for blood thinner. You could learn CPR and signs for brain attack. Go to the american heart association website. AED may be beneficial but they are expensive.