I worry at night as my heart keeps racing

Q RECENTLY I’ve been having heart palpitations which wake me at night. Most worrying is when my heart misses a beat and I lie there and fear it will stop altogether. Could you shed some light on this? Michael Byrne, Carlisle.

A This must be unsettling and my suggestion is that further investigation is needed to get to the bottom of the cause, so appropriate treatment can be offered.

in your longer letter you explain that you have been advised to call an ambulance if the sensations persist for more than 20 minutes, which is far from reassuring.

A resting electrocardiogram (ECG) — a test that measures the electrical activity of the heart to check rhythm — showed that your heart was normal at the time of the tracing. however, this type of oneoff check is limited because it can’t exclude coronary heart disease — furring up of the arteries, which may cause palpitations. Nor can it tell you anything about the cause of the episodes you have experienced.

Doctors need to capture and identify the rhythm of your heart during one of the episodes, using a 24-hour ambulatory ECG recording, sometimes known as a holter monitor.

At the innocent end of the spectrum are ectopic beats, or extrasystoles, which are normal, but excessive runs may indicate a thyroid problem. Other possibilities include more significant rhythm abnormalities, such as atrial fibrillation, when the heart beats too rapidly and irregularly.

in the meantime, you indicate you have been prescribed statins as your doctor has calculated you have a 33 per cent risk of suffering a heart attack or stroke in the next decade (given your cholesterol levels). This may or may not relate to the cause of the palpitations, but do accept this advice.

Q IS THERE any cure for cold sores or any likelihood of one in the near future? I get them intermittently and not only find them embarrassing, but fear passing on the virus responsible to my grandchildren.

Bill Adair, by email.

A COLD sores are caused by the herpes simplex virus. More than 60 per cent of adults are infected at some point in their lives, and it is transferred by infected oral secretions, such as saliva.

Following an infection, the virus establishes itself in local nerve tissue. Once it’s in you, it is there for ever. in up to 40 per cent of cases, the virus reactivates throughout life, usually as a cold sore.

Triggers include exposure to sunshine and minor illnesses such as colds. Other conditions that undermine the immune system can also initiate attacks.

Most people have warning symptoms a day or so before the cold sore erupts, with pain, burning or tingling at the site; blistering then occurs, rapidly evolving into an ulcer which crusts.

You are right to be concerned that you could pass it on to others, and the only way to prevent transfer is to avoid skin-to-skin contact when a cold sore is apparent.

There is no cure — not yet — and no vaccine to protect against primary infection. The only treatment is anti-viral drugs, which keep the virus locked in a dormant state.

Zovirax ( acyclovir) cream, available over the counter, is an effective drug that stops the virus becoming fully active — if applied promptly at the start of an episode, the momentum is interrupted and the duration is shortened.

There have been trials looking into preventative treatment for those with recurrent attacks. Acyclovir pills, when taken twice daily for up to a year, have been found to help people who experience six or more attacks per year — but there are concerns about using antiviral drugs continuously.

i am sorry to be the bearer of not very helpful tidings about the possibilities of a cure.

WRITE TO DR SCURR

WRITE to Good Health, Daily Mail, 2 Derry Street, London W8 5TT or drmartin@dailymail.co.uk — include your contact details. Dr Scurr cannot enter into personal correspondence. Replies should be taken in a general context and always consult your own GP with any health worries.