I want everyone to have this information. Some of the symptoms aren't what you might think, and I know/know of some very smart people who've witnessed heart attacks and didn't know it at the time. A lot of this is direct from various heart and stroke websites and covers heart attack, cardiac arrest and various forms of stroke.

A heart attack occurs when blood flow to a section of heart muscle becomes blocked. If the flow of blood isn’t restored quickly, the section of heart muscle becomes damaged from lack of oxygen and begins to die. A person having a heart attack may feel sudden pain:
* Sudden discomfort or pain that does not go away with rest
* Pain that may be in the chest, neck, jaw, shoulder, arms or back
* Pain that may feel like burning, squeezing, heaviness, tightness or pressure
* In women, pain may be more vague
* Chest pain or discomfort that is brought on with exertion and goes away with rest
They may also have a shortness of breath, or indigestion/nausea/vomiting, and/or have cool, clammy skin, and/or experience anxiety or denial. So a person who's got indigestion, some pain, is anxious and telling you to piss off may be having a panic attack - or a heart attack.
So what do you do? If it's you, stop telling people to piss off, you're just agitating yourself and looking like a moron. Whoever can should call 911. The person experiencing the possible heart attack should stop what they're doing, sit or lie down, try to relax. If they/you take nitroglycerin, take the normal dose. If they/you experience chest pain, chew (which is gross, do it anyway) one adult 325 mg tablet or 2 80 mg tablets of ASA (acetylsalicylic acid, commonly referred to as Aspirin®). Pain medicines such as acetaminophen (commonly known as Tylenol®) or ibuprofen (commonly known as Advil®) do not work the same way as ASA (Aspirin) and therefore will not help in the emergency situation described above.

If you're alone, wait for help. You've called 911, right? If not, call them now. You may have seen an email about coughing to keep the heart going if you're alone and suspect you're having a heart attack. The Heart and Stroke website advises to ignore this email. Think about it, if your goal is to rest and keep calm how is forcing deep coughs going to help? And you've received a lot of bullshit emails, right? The coughing thing was one of them, don't do it.

Cardiac arrest is something different. Cardiac arrest is the sudden, abrupt loss of heart function. The victim may or may not have diagnosed heart disease. Sudden death (also called sudden cardiac death) occurs within minutes after symptoms appear.During cardiac arrest a victim loses consciousness, stops normal breathing and loses pulse and blood pressure. If you're alone and experience cardiac arrest, you're fucked. On the up side according to some doctors I've spoken to, you're not going to feel a thing, you're just going to drop, may not have any warning of something amiss. You'll remain unconscious as your body dies. If you're in front of someone who's dropped for no apparent reason and isn't responding to their name, being shaken or shouted at, check for pulse, breathing. Tilt their head back and listen for breathing for a maximum of 5 seconds. No breathing, pulse, response? Might be cardiac arrest. If there are other people around, have someone call 911. Tell someone to get an Automated External Defibrillator (AED) if one is available. Most gyms have them now, all fire trucks do and there's one every 20 ft (from what I've heard) at Pearson airport. If none is available, begin CPR if you know it.
If you're alone with a person appearing to be experiencing cardiac arrest, call 911, get the AED yourself if one is available. If none is available, begin CPR if you know it. The main message here is learn CPR.

Stroke is something different again. A stroke is a sudden loss of brain function. It is caused by the interruption of flow of blood to the brain (ischemic stroke) or the rupture of blood vessels in the brain (hemorrhagic stroke). Effects and damage are going to depend on where the stroke occurred.

We can all thank the episode of House with the pregnant photographer for the FAST way of recognizing a stroke. Remember?
F = Face. Is your smile crooked? Is part of your face drooping?
A = Arms. Are you able to raise your arms to the same level in front of you? No? Weakness on one side, my friend.
S = Speech. Subject, noun, verb, give it a try. If you suddenly are having trouble speaking, that's a bad thing.
T = Time. You're having a stroke. Get medical attention immediately. The longer you wait, the more damaged (or dead) you'll be.

There are other symptoms though. Massive sudden headache, dizziness and vision problems are additional things you should watch for. If you or someone in front of you seems to be having a stroke, get medical attention immediately. It may be nothing but are you a doctor? No? Well, let one decide. The faster you get to help, the better your chances for surviving well are. There are medications you may be given during your stroke at a hospital, whether they're appropriate to your circumstance are up to the health care providers on staff.

And that's it. It's a cliche to say that lots of hearts break when one does, but it's also a fact. The sudden loss of someone to heart attack or stroke is as much of a shock to loved ones as losing them to a car crash or bullet. You have one heart, and it's precious. You have one mind, and it's valuable. Take care of both. Educate yourself and people around you, take CPR courses with friends. Eat real food in appropriate amounts. Don't smoke. Exercise regularly. Enjoy your life and be happy. You are loved.