(AP) -- (AP) - It's not a perfect test. Yet researchers report a key step for the first gene test aimed at reducing unnecessary angiograms - expensive and somewhat risky procedures that hundreds of thousands of Americans have each year to check for clogged arteries. Most of these exams, done in hospital cardiac catheterization labs, turn out negative.

A simple blood test to show who truly needs an angiogram would help, and 6,000 people have had the gene test since it went on sale last year. It has drawbacks. It suggests too many chronic chest pain sufferers have heart disease when they really don't, and misses it in others who do.

Several heart experts say they need to see better results before they'd use it. But similar tests are used now to guide breast cancer treatment and organ transplants, and many doctors think they'll eventually prove valuable for heart disease as more genes are discovered that affect risk.

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