Coronary angioplasty is a procedure in which atherosclerotic plaques which build up and clog the coronary arteries are compressed against the vessel wall by expanding a balloon-like device inserted through a catheter that has been threaded through the artery. Hundreds of thousands of these procedures are performed in the United States each year. Up to 40 percent of patients who undergo this procedure develop restenosis or new blockage, erasing the initial benefit and warranting repeat angioplasty or by-bass operation. Therefore “restenosis” has been named by some experts as a modern plague that adds a considerable burden to health care costs, according to UCSD cardiologist Guido Schnyder, M.D., who led the study and is a visiting scholar from Switzerland.
Schnyder found that in patients who orally ingested a vitamin pill containing one milligram of folic acid, 400 micrograms of vitamin B-12 and 10 milligrams of vitamin B-6 the chance of restenosis dropped 48 percent.
It has long been known that these vitamins lower homocysteine levels, and that slightly elevated homocysteine levels are associated with increased risk of heart disease, Schnyder said. This is the first ever clinical trial to examine the effects of these vitamins on heart disease.
Of the 205 patients – all from the Swiss Cardiovascular Center – in the double-blind randomized study, 105 were given B-vitamins and 100 were given placebo. Of the group of patients receiving placebo, 37.6 percent experienced restenosis, while only 19.6 percent of those taking the B-vitamins developed repeat blockage.
“This has proven to be a very effective and inexpensive treatment for preventing coronary restenosis,” Schnyder said.
As a result of these findings, in which no adverse effects were detected, Schnyder said he suggests physicians put their patients on this vitamin regimen following successful angioplasty.
The study was funded by the Swiss National Science Foundation and Swiss Cardiovascular Center at the University Hospital in Bern, Switzerland. Also involved in the study were Marco Roffi, M.D. (The Cleveland Clinic Foundation, Cleveland, OH), Riccardo Pin, M.D., Yvonne Flammer M.D. (Swiss Cardiovascular Center, University Hospital Bern, Switzerland), Helmut Lange, M.D. (Kardiologische Praxis, Bremen, Germany), Franz R. Eberli, M.D., Bernhard Meier, M.D. (Swiss Cardiovascular Center, University Hospital Bern, Switzerland), Zoltan G. Turi, M.D. (University of California, San Diego), and Otto M. Hess, M.D. (Swiss Cardiovascular Center, University Hospital Bern, Switzerland).
Journal
New England Journal of Medicine