London, Sept. 13 (Reuters): Drinking moderate amounts of alcohol can cut further narrowing of the arteries in patients who have had heart surgery, researchers said today.

The benefits of drinking reasonable amounts of alcohol to reduce the risk of heart disease are well known, but scientists at Heidelberg University in Germany have shown that even after the damage has been done and repaired, alcohol has a protective effect.

In patients who had surgery to open up a blocked artery, alcohol cut the risk of restenosis, or re-narrowing of the treated artery, which occurs in 30-40 per cent of patients in the first four months afterwards.

?Alcohol consumption in this patient population reduced the incidence of restenosis,? said Dr Feraydoon Niroomand, a cardiologist at the university. ?This is the first time it has been shown in patients.?

Coronary heart disease is a major cause of death in industrialised countries. Niroomand and his team questioned 225 male patients who had balloon angioplasty about how much alcohol they drank in the first few month after the procedure.

Balloon angioplasty is a standard treatment for heart disease. It involves inserting a very tiny balloon into the artery, inflating it and putting a tube in place to hold the artery open so blood can flow freely through it.

The researchers, who reported their findings in the journal Heart, found that patients who drank little or no alcohol had more blocked arteries, worse cholesterol levels and poorer heart function than patients who drank 50 gms of alcohol, or about a bottle of wine or 2.5 litres of beer, a week. They were also more likely to need a repeat angioplasty.

?There are data from experimental studies that show alcohol reduces the proliferation of smooth muscle cells which constitute the majority of the vessel wall and which are also responsible for this renarrowing,? Niroomand said.

Niroomand said, though, that the results should not encourage people to take up or increase their drinking.