Taking a combination of folic acid, vitamin B12 and vitamin B6 over a six-month period can help prevent the recurrence of blocked arteries in patients who have undergone coronary angioplasty, according to a study published this week.
Dr Guido Schnyder, an assistant professor in the cardiology division at the University of California at San Diego, and his colleagues reported on the findings in this week's Journal of the American Medical Association.
Schnyder's team previously studied the effects of the same vitamin blend on heart disease. Published in November 2001 in the New England Journal of Medicine, the first study involved 205 patients who were given either the vitamin combination of folic acid, vitamin B12 and vitamin B6 or a placebo for six months.
The patients who took the vitamin combination showed a 48 per cent reduction in the development of restenosis, or renarrowing of the vessel, compared to patients who received the placebo.
The vitamin treatment works by lowering the levels of homocysteine, an amino acid which causes heart attacks.
In the new study, Schnyder added 348 patients and extended the follow-up observation period from six months to one year.
''It was important to follow these patients for another six months, because that's the time frame in which restenosis typically occurs,'' he said in an Associated Press story. "We've now shown that the vitamin combination didn't just delay the development of restenosis, it prevented it.''
Schnyder also expanded the study's focus to look at the patient's need for repeat angioplasties or heart bypass operations. The vitamin regime apparently decreased by 38 per cent the need for repeat angioplasties or heart bypass operations.
Dr Robert Bonow, chief of cardiology at Northwestern Memorial Hospital in Chicago and president of the American Heart Association, said the study offers more evidence that B vitamins are important in maintaining healthy blood vessels. More research is needed, though, he said.
''When you have a small trial like this, it's always nice to have confirmation by another group,'' Bonow said.
The study was funded by the Swiss National Science Foundation and Swiss Cardiovascular Center and the University Hospital in Bern, Switzerland.