Q2: My husband has a bad heart and he has been advised to have the arteries stented. We would like some more information on this berforehand as what to expect. From reading your answer to others, I know he would have to take the anticloting tablet clopidogerl for twelve months. We would like to know what happens after twelve months when he comes off the tablets. Do you have regular blood tests to make sure the blood does not clot, and six month checkups to make sure everything is fine. Basically after this type of procudure would there be any follow up treatment if so how long for and by the hospital or your own GP? Name and address withheld.

A2: Increasingly stents, small metal mesh cages, are fitted at the same time as a patient has had the blood flow through their coronary arteries improved with balloon angioplasty. In balloon angioplasty a small tube is threaded into the coronary artery, the balloon inflated and the fatty atheromatous tissue is pressed back against the arterial wall. The decision is often taken to leave behind the stent that has also been inserted in the artery so that after the tube has been withdrawn the wire expands to the size of the balloon, embeds itself in the artery wall and keeps the artery wall expanded.

Some stents contain a chemical that slowly leaks out from the metal and helps to prevent the artery from re-closing. There is considerable controversy about the number of patients who would do better with one of these chemically enhanced stents, drug eluting stents, rather than with a simple metallic stent. Cost effectiveness is an important consideration, but not only in this case, for the NHS when deciding on treatment.

There is also a resurgence of the discussion about the number of patients that should have a stent, or stents, fitted, rather than a bypass operation. The introduction of stents represented a major advance as patients are spared major surgery. However a survey within the last month or two has shown that possibly the enthusiasm for stents has now gone far enough and that some people would have been better off having a bypass.

You are quite right the officially approved time for giving clopidogrel is twelve months. So far as I have been able to discover this is as much an administrative decision based on cost-effectiveness as it is on clinical effect. It also happens to be the length of time of the surveys that demonstrated its benefit over aspirin. Watch this space, as it were, as I have a suspicion that the twelve month recommendation will be extended in time as the results of more research surveys become available. Your follow-up regime will be dependent on your doctors and on your own condition.

Q3: My cousin who is in his early seventies and has previously seemed in good health, so much so he regularly helps as a volunteer with a gardening project, has just suffered a stroke three weeks ago. He felt unwell and then became unconscious. Fortunately his wife was with him at the time and was able to get immediate help from a paramedic ambulance in the vicinity. He seems to have suffered no lasting effects although is not allowed to drive. Is it unusual for a stroke to be preceded by no symptoms. What should we look out for in the future with him and is there likely to be a recurrence? Name and address withheld.

A3: Yes. Strokes can, and often do, appear without any previous warning. Your cousin's story is not unusual. Patients have frequently told me that they are unwell before lapsing into unconsciousness. The chances of having a recurrence are mainly dependent on age and the underlying cause of the stroke. Is it ischaemic, from a clot, or haemorrhagic from a bleed? Is the patient having medical care and do they have a history of diabetes, high blood pressure, raised cholesterol levels, obesity or any other condition, including smoking nicotine or alcohol binging, that might affect his cardiovascular system. If so has it been adequately treated?

As you will understand the prognosis in strokes varies enormously according to individual circumstances. About 120,000 people, excluding those who only have a TIA, have a stroke in Britain each year. As a rough guide, no more than that, about twenty per cent will die soon in hospital, ten per cent will make a complete recovery with no obvious evidence of any lasting neurological damage. About 50 per cent will have severe to moderate paralysis down one side and another 20 per cent will have obvious but minor neurological problems. One factor that is important is early admission to a specialised unit in hospital.

Warning signs of a stroke are:

1. sudden weakness in an arm, leg or one side of the face,
2. sudden numbness on one side of the face or body,
3. sudden loss of sight or dimness of vision, especially important if it is only one side,
4. sudden difficulty in speaking or in understanding what others are saying,
5. sudden dizziness or loss of balance,
6. sudden headache especially if it is excruciating - patients often say "this is the worst headache I have ever had in my life doctor", others say that the onset is so sudden that it feels as if someone has hit them over the head. These headaches are known as thunderclap headaches and in about 25 per cent of cases as the result of a cerebral bleed.

Q4: Do strokes run in families or are they more attributable to lifestyle? Name and address withheld.

A4: Some types of strokes, such as those that stem from aneurysms in the arteries in the brain, certainly run in families. Similarly so do those that follow bleeding from the congenital formation of aberrant bunches of blood vessels. Cardiovascular disease including high blood pressure, diabetes and hyperlipidaemia, any and all of which may predispose to strokes, are to some extent familial. Even if there is a family tendency to have strokes the risk can be reduced by circumstances and lifestyle including: