Around a quarter of all people in the UK die from cardiovascular disease every year. This refers to any disease or condition that affects the heart or circulatory system.

It includes heart failure, which occurs when the organ is unable to pump blood around the body properly. Usually this is because it has become too weak or stiff to do so.

Heart failure is a serious long-term condition that often gets progressively worse over time. Therefore, spotting any of the warning signs is essential.

Some of the symptoms are more well known. Heart palpitations and shortness of breath, for example, can indicate heart failure.

However, others are less so and might appear where you least expect it.

Speaking on TikTok, Doctor Suraj Kukadia, revealed an unusual sign of heart failure to spot in your legs.

The NHS GP and A&E clinician, who is better known as Dr Sooj, responded to another video in which the creator was pressing down on their leg with their thumb and leaving a lasting dent.

“Does anyone know if I need to see a doc for this?” they asked.

In reply Dr Sooj warned his more than 59,000 followers that this should prompt a visit to their GP.

He explained: “That is a positive indentation test for pitting oedema.

“There are many causes and it varies in severity but indicates fluid retention.”

One such cause is heart failure, although it can indicate a number of other issues.

Dr Sooj continued: “Some common causes include heart failure, kidney disease, liver disorders, pregnancy and even certain medications.

“It can also be caused by sitting down for too long and having poor mobility. We treat it by treating the underlying cause.”

Oedema is a common phenomenon among heart failure patients.

If the heart cannot pump blood properly around the body you get a build-up of pressure inside the blood vessels.

This then causes fluid to leak into the surrounding tissues.

When listing signs of heart failure, the NHS says: “Swollen ankles and legs – this is caused by a build-up of fluid (oedema); it may be better in the morning and get worse later in the day.”

According to the NHS, “common” signs of heart failure include:

• Breathlessness – this may occur after activity or at rest; it may be worse when you’re lying down, and you may wake up at night needing to catch your breath
• Fatigue – you may feel tired most of the time and find exercise exhausting
• Feeling lightheaded and fainting.

Less common signs include:

• A persistent cough, which may be worse at night
• Wheezing
• A bloated tummy
• Loss of appetite
• Weight gain or weight loss
• Confusion
• A fast heart rate
• A pounding, fluttering or irregular heartbeat (palpitations).

If you experience any symptoms you should speak to your GP.