Heart attacks are a serious medical emergency, and should be treated immediately.
The condition, which is also known as a myocardial infarction, is caused by the flow of blood to the heart becoming blocked.
Without enough blood, the heart muscle can become seriously damaged, and may even be life-threatening.
You could be more likely to have a heart attack if you have swollen feet or ankles, it’s been claimed.
Having swollen legs, ankles or feet may be an early warning sign of a myocardial infarction, warned medical website WebMD.
It could be a sign that the heart isn’t working as well as it should be, it said.
If the heart isn’t working properly - a condition known as heart failure - it may cause a build-up of fluid in the lower extremities.
The build-up is known as oedema, and it may get worse later on in the day.
Heart failure could also cause blood to back-up in the veins, which may lead to stomach bloating.
“If something went wrong with your heart, would you know it? Not all heart problems come with clear warning signs,” it said.
“There is not always an alarming chest clutch followed by a fall to the floor like you see in movies.
“Some heart symptoms don’t even happen in your chest, and it’s not always easy to tell what’s going on.
“[If] your legs, feet, and ankles are swollen, [it] could be a sign that your heart doesn’t pump blood as effectively as it should.
“When the heart can't pump fast enough, blood backs up in the veins and causes bloating. Heart failure can also make it harder for the kidneys to remove extra water and sodium from the body, which can lead to bloating.”
More common heart attack symptoms include chest pain, feeling dizzy, or having an overwhelming sensation of anxiety.
The signs of a heart attack can vary from person to person, and they may develop over a number of weeks or months.
Speak to a GP if you have any symptoms of heart failure, urged the NHS.
Signs of heart failure may be caused by another underlying medical condition, but it’s still best to get them checked, it said.
If you suspect you may be having a heart attack, you should dial 999 straight away, and ask for an ambulance.
Don’t worry if you’re unsure whether you’re having a heart attack or not. Paramedics would rather be called out for a false alarm, rather than turn up too late.