Vitamin C Shows Promise in Heart Failure PatientsOctober 29, 2001 By Amy Norton
NEW YORK (Reuters Health) - Therapy with vitamin C may help heart failure patients by improving the function of their blood vessels, results from a small study suggest.
However, researchers say it is too early to recommend the vitamin as a treatment for congestive heart failure.
In a study that looked at vitamin C treatment in 34 patients with congestive heart failure--as well as how the vitamin affected cells in the test tube--German and French researchers found that the vitamin appeared to keep cells in the blood vessel wall from dying. They say this protection from cell death could explain previous study findings suggesting that vitamin C benefits blood vessel function in people with congestive heart failure.
Researchers led by Dr. Stefanie Dimmeler, of the University of Frankfurt in Germany, report the findings in the October 30th issue of Circulation: Journal of the American Heart Association.
Congestive heart failure occurs when the heart cannot pump efficiently enough to meet the body's needs, resulting in symptoms such as fatigue and shortness of breath. Heart failure usually results from an underlying heart condition such as coronary artery disease.
Heart failure patients also show poor function in the blood vessel walls, and research suggests that damaging forms of oxygen called reactive oxygen species accumulate in the blood as the condition progresses, Dimmeler told Reuters Health. This oxidative stress, she explained, may contribute to dysfunction in the blood vessel wall--called the endothelium--by killing off endothelial cells.
Vitamin C is an antioxidant, which means it helps remove cell-damaging oxygen compounds from the body. "Therefore," Dimmeler said, "we questioned whether antioxidative treatment of heart failure patients with vitamin C against these reactive oxygen species can reduce endothelial cell death."
She and her colleagues gave 34 patients either vitamin treatment or an inactive placebo. Treated patients first received an intravenous dose of vitamin C, followed by 3 days of oral supplements. All were on standard drug treatment for heart failure.
Before treating the patients, the researchers had found in experiments that exposing endothelial cells to vitamin C kept certain inflammatory proteins from pushing the cells to "commit suicide"--a process called apoptosis.
Similarly, when they examined blood samples from the patients, they found that those who received vitamin C showed far less evidence of apoptosis in endothelial cells than they had before treatment. Placebo patients showed no such change.
According to Dimmeler, these findings may help researchers better understand the mechanisms behind heart failure, and suggest that either dietary vitamin C or heart failure drugs with added antioxidant properties could slow the course of the disease.
"However," she said, "(vitamin C) has not yet been proven to prevent disease progression in congestive heart failure."
SOURCE: Circulation 2001;104.