JACC: Vitamin C infusion improves microcirculatory reperfusion
In patients undergoing elective PCI, impaired microcirculatory reperfusion is improved by vitamin C infusion, suggesting that oxidative stress is implicated in such a phenomenon, according to a study published in the February issue of the Journal of the American College Cardiology: Cardiovascular Interventions.

Francesco Violi, MD, professor, department of experimental medicine, University of Rome in Italy, and colleagues compared 1 g vitamin C infusion (16.6 mg/min, more than 1 hour before PCI) versus placebo in 56 patients with stable angina.

At the baseline, thrombolysis in myocardial infarction (TIMI) perfusion grade less than 2 was observed in 86 percent of the vitamin C infusion group and 89 percent in the placebo group; the percentages decreased 4 percent in the vitamin C group and 32 percent in the placebo group after PCI, according to Violi and colleagues.

“Complete microcirculatory reperfusion (TIMI grade 3) was achieved in 79 percent of the vitamin C-treated group compared with 39 percent of the placebo group; 8-hydroxy-2-deoxyguanosine  and 8-iso-prostaglandin F2alpha  plasma levels significantly increased in the placebo group while they were significantly reduced in the vitamin C-treated group,” the authors wrote.

Researchers noted that TIMI grade changes from the baseline showed significant correlation with 8-hydroxy-2-deoxyguanosine or 8-iso-prostaglandin F2alpha plasma levels changes.

“Vitamin C has a short half-life and therefore, reperfusion amelioration would probably be a consequence of a short-term effect on arterial dilation; and other mechanisms, such as a decrease of micro-embolization, which would require a prolonged effect, are unlikely but cannot be excluded,” they said.