Positive Health Online

Abstract

TARDIF and colleagues, Department of Medicine, Montreal Heart Institute, Quebec Canada write that oxidising metabolites generated at the site of coronary angioplasty induce chain reactions which can lead to restenosis (re-narrowing of coronary arteries). They state that antioxidants may counter oxidative stress, modify formation of new internal blood vessels, and possibly prevent restenosis following angioplasty. @m: The authors conducted a double-blind, randomised trial to study whether drugs with antioxidant properties decreased incidence and severity of restenosis. 317 patients were randomly assigned to receive one of 4 treatments: 1) placebo; 2) probucol 500 mg; 3) multivitamins 30,000 IU beta carotene; 500 mg vitamin C; 700 IU vitamin E; or both probucol and multivitamins. All treatments were given twice daily, for 4 weeks prior to and 6 months following angioplasty. Patients also received an extra 1000 mg probucol, 2000 IU vitamin E, both probucol and vitamin E or placebo 12 hours prior to angioplasty, according to treatment assignments. @r: Mean reduction in luminal diameter 6 months following angioplasty was as follows: probucol group - 0.12 +/- 0.41 mm; combined treatment group 0.22 +/- 0.46 mm; multivitamin group 0.33 +/- 0.51 mm; and placebo group 0.38 +/- 0.50 mm. Restenosis rates per segment were as follows: probucol group 20.7%; combined treatment group 28.9%; multivitamin group 40.3%; and placebo group 38.9%. Rates of repeat angioplasty were: probucol 11.2%; combined treatment 16.2%; multivitamin group 24.4%; and placebo 26.6%. @c: The antioxidant probucol is effective in reducing the restenosis rate following balloon coronary angioplasty. @q:Tardif JC et al. Probucol and multivitamins in the prevention of restenosis after coronary angioplasty. Multivitamins and Probucol Study Group. N Engl J Med 337(6): 365-72. Aug 7 1997.

Background

Methodology

Results

Conclusion

References

Comment

Probucol is a drug used to treat high cholesterol levels, which works by inhibiting the uptake of fat by the liver. Probucol was clearly superior to antioxidant multivitamins in this trial in reducing restenosis to coronary angioplasty. However, treatment of this condition using various regimes of antioxidant therapy and/or EDTA chelation therapy has also been successful and in some cases has obviated the need for surgery. See also Levine et al in Positive Health Issue 15 (Oct/Nov 1996) and Kritchevsky et al in Issue 11 (April/May 1996).