Chest pain that lasts more than a few minutes and doesn't ease with rest is treated as a heart problem until proven otherwise.
ACT
- Have them sit or lie down, in whatever position they breathe best. Often sitting, back supported, knees bent. Don't make them walk, and don't let them drive.
- Have someone call for help immediately. It's the only action that really changes the outcome: time is heart muscle.
- Loosen anything tight: collar, belt, tie.
- Ask whether they're being treated for their heart and whether they have medicine prescribed for this kind of attack. Help them take it if they have it, and never offer a medicine that isn't theirs.
- Stay with them and speak calmly. Anxiety increases the heart's need for oxygen.
- Watch consciousness and breathing constantly. If they stop, start compressions immediately: see Unconscious person.
- Find out if there's a defibrillator nearby and have it brought.
Give nothing to eat or drink. Don't massage the chest of a conscious person.
ADAPT
The pain is typical: tightness or heaviness in the middle of the chest, like a vice, which may spread to the left arm, both arms, the jaw, the back or the stomach. It lasts, and doesn't change with breathing or position. Sweating, paleness, nausea and anxiety often come with it.
The pain is atypical, and that's common. In women, elderly people and people with diabetes, a heart attack often comes without the classic pain: unusual breathlessness, sudden exhaustion, feeling unwell, pain in the pit of the stomach, nausea. These presentations are under-diagnosed precisely because they don't match the expected picture.
It's just a faint. Paleness, sweating, blurred vision, the feeling of passing out. Lay the person down and raise their legs; they recover quickly. If they don't come round within a few minutes, treat it as serious.
The pain gets worse with a deep breath or changes with position. That points more towards a breathing or chest-wall cause, often less serious — but sudden, intense breathlessness, especially after a long period of immobility, is also an emergency.
It's very hot or very cold. Heatstroke and hypothermia also cause faints, with opposite treatments: see Heatstroke and Hypothermia.
The person refuses to call for help. It's extremely common, out of embarrassment or denial. Call anyway. An unnecessary call costs nothing; a late call costs heart muscle that won't come back.
You're very far from everything. Strict rest, no walking, a comfortable position, gentle warming, constant watch, and be ready to resuscitate. See Examining a casualty for monitoring and Signaling and getting found for calling for help.
UNDERSTAND
The heart is a muscle, and like every muscle it needs a blood supply. Its own arteries, the coronary arteries, feed it with blood. When one of them becomes blocked, the part of the muscle it feeds stops getting oxygen and starts to die.
It's a process measured in minutes. Every minute without blood flow destroys muscle that won't regenerate. The whole logic of treatment comes down to this: the sooner the vessel is reopened, the more heart is left.
Two practical consequences follow.
Effort makes it worse. A working muscle needs more oxygen. Making someone walk to a car, climb stairs or drive directly increases the damage. That's why they're kept still.
Cardiac arrest can happen without warning. The damaged area disrupts the heart's electrical activity, and fibrillation can start at any moment, even in someone who is still talking. That's the reason for constant watching, and for finding a defibrillator before it's even needed.
On diagnosis, one thing must be clear: in the field, you can't tell a heart attack from harmless chest pain. Much chest pain isn't cardiac, and many heart attacks don't look like heart attacks. The right rule is lopsided: calling for nothing costs nothing; calling too late is final.