Most of the time lost in a heart attack is lost before the 999 call: the average person waits two to three hours, because what they feel does not match what they were expecting. This chapter is about what a heart attack feels like when it does not look like the films, what to do in the first minutes, and the three things that make people wait when they should not.
1. The classic picture
A pressure, tightness, squeezing or heaviness in the centre of the chest — "like a band" or "like an elephant sitting on me" more often than a sharp pain — lasting more than fifteen minutes, not changed by breathing or position, often spreading to the left arm, both arms, the jaw, the neck or the back, with sweating, nausea, breathlessness and a sense of dread. It comes on at rest as often as on exertion. Around two-thirds of heart attacks look something like this. The other third are the rest of this chapter.
2. The presentations that are not chest pain
| How it presents | What it gets called | What should prompt the 999 call |
|---|---|---|
| Breathlessness alone, sudden or over hours, often with sweating | Asthma, a chest infection, anxiety, "getting old" | New breathlessness at rest with no wheeze and no fever, especially in someone over 60 or with diabetes, is a heart attack until an ECG says otherwise |
| "Indigestion": a burning or heavy feeling in the upper stomach or lower chest, sometimes with belching, nausea or vomiting | Indigestion, reflux, something they ate | Indigestion that started with exertion, comes with sweating or breathlessness, or does not settle with an antacid within a few minutes. The inferior wall of the heart sits on the diaphragm and presents this way |
| Jaw, throat, neck, shoulder or arm pain with no chest pain, sometimes an ache in the teeth | Dental, a pulled muscle, arthritis | Pain that comes with exertion and goes with rest, or arrives with sweating and nausea, in a place that has never hurt like that before |
| Collapse, fainting, sudden weakness | A faint, low blood pressure, dehydration | Any collapse in someone over 50, or with known heart disease, is a heart problem until proved otherwise. Do not let them "sleep it off" |
| Palpitations: a racing, pounding or irregular heartbeat | Anxiety, caffeine, a panic attack | Palpitations with chest discomfort, breathlessness, faintness or a heart rate that stays over 150 at rest. A new irregular pulse in someone over 60 is atrial fibrillation until an ECG says otherwise, and that is a stroke risk (see the rhythm chapter) |
| Sudden extreme fatigue or "flu without the fever" over hours to a day or two, sometimes with cold sweats | A virus, overwork | Commoner in women and in older people; recognised in retrospect. A sense that something is badly wrong, out of proportion to any symptom, is worth acting on |
| Confusion, or a fall, in an older person | Dementia, a urinary infection | A silent heart attack presents this way in the very old; an ECG and a troponin are cheap |
Women. Women have the classic chest pain as often as men do, but are more likely to have the other symptoms as well or instead: breathlessness, nausea, back and jaw pain, fatigue. They are also more likely to delay calling, more likely to be misdiagnosed on arrival, and less likely to be given the treatments the guidelines say everyone gets. The 2025 American and 2023 European guidelines both say so in as many words. If you are a woman with any of the symptoms above and a feeling that something is wrong, say "I think I am having a heart attack" on the phone and at the door.
Diabetes and age. Nerve damage from diabetes blunts the pain, so a heart attack in someone with long-standing diabetes is more often silent or presents as breathlessness or collapse; the same is true over 75. Around a third of heart attacks in these groups are found on a routine ECG months later, as an old scar nobody knew about.
3. Angina, and the change that matters
If you already have angina, you know your pattern: how much exertion brings it on, how long it lasts, and that the GTN spray settles it. The heart attack often announces itself as a change in that pattern: pain at rest or in bed; pain with less exertion than before; pain lasting longer or needing more spray; pain with sweating or breathlessness that never used to accompany it. The NHS rule for the spray: one dose, wait five minutes, a second dose, wait five minutes, and if the pain is still there, call 999. Do not take a third and wait again.
4. What to do, in order
Call 999 and say "chest pain" or "I think it's a heart attack"
Not 111, not the GP, not a lift to hospital: the ambulance crew carry the ECG that diagnoses a STEMI and can pre-alert the catheter laboratory from the roadside, which saves the hour that matters most. If you are alone and the phone is not to hand, unlock the door first, then call.
Sit down and stop
Sitting, knees bent, back supported. Not lying flat if breathless. No walking to the car, no climbing stairs to fetch things. Exertion increases the size of the infarct.
Aspirin 300 mg, chewed
One adult aspirin (300 mg) chewed slowly, not swallowed whole, unless you are allergic to it, have been told never to take it, or are under 16. It reduces the clot in the artery and reduces death. If the 999 call handler tells you to take it, take it; if you have already taken it, tell the crew. Low-dose 75 mg tablets are not enough — four of them are.
GTN if you have it
Your own spray, as above. Not someone else's; not if you have taken sildenafil or similar in the last 24–48 hours (the combination drops blood pressure dangerously) — and tell the crew if you have.
Unlock the door, gather the medicines, and wait
The medicine list and the time the pain started are the two things the crew need. Do not eat or drink. If the person becomes unresponsive and is not breathing normally, start CPR and send someone for a defibrillator: the resuscitation chapter.
5. Three things that make people wait, and should not
- "It might be nothing." Half of chest pain arriving by ambulance is not a heart attack, and that is the system working. A normal ECG and troponin take an hour; a missed heart attack takes muscle. Nobody in an emergency department is annoyed by a chest pain that turns out to be indigestion.
- "I'll see if it passes." Heart muscle dies at a rate that depends on the artery, but the first hour after a complete blockage is when most of the muscle that can be saved is saved. The treatment window is not four hours; it is now, with the benefit falling every quarter-hour.
- "I don't want to make a fuss / go to A&E on a Friday night." A STEMI does not go to A&E; the ambulance takes it directly to the catheter laboratory, day or night, and the crew's ECG is what makes that happen. Calling later means arriving without that ECG and joining a queue.
6. What not to do
- Do not drive yourself, or let a family member drive you: no ECG, no pre-alert, and a collapse at the wheel.
- Do not take painkillers other than aspirin: ibuprofen and the other anti-inflammatories are harmful in a heart attack.
- Do not "cough repeatedly" (a persistent internet myth; it does nothing).
- Do not take someone else's GTN, beta-blocker or anticoagulant.
- Do not wait for the GP to open.
7. After the ambulance arrives
The crew take a 12-lead ECG within ten minutes. If it shows a STEMI they will go straight to a heart attack centre, bypassing the nearest hospital if necessary, and phone ahead so the catheter laboratory team is ready. If it does not, they go to the emergency department, where the timed troponin pathway in the clock chapter decides whether it is a heart attack within an hour or three. Either way, say when the pain started as a clock time, and hand over the medicine list.
8. Where UK and US guidance differ
Not on recognition or the first steps. Both countries' guidelines say aspirin, 999 (911), an ECG within ten minutes and direct transport to a PCI centre for a STEMI; both name the atypical presentations, women, diabetes and the elderly. The US guideline adds that emergency medical services should transmit the ECG ahead; UK ambulance services do the same in practice.