Effects of coenzyme Q10 on exercise tolerance in chronic stable angina pectoris.

The effects of coenzyme Q10(CoQ10) on exercise performance were studied in 12 patients, average age 56 years, with stable angina pectoris. The study involved a double-blind, placebo-controlled, randomized, crossover protocol, using multistage treadmill exercise tests. CoQ10(150 mg/day in 3 daily doses) was administered orally for 4 weeks, tended to reduce anginal frequency from 5.3 +/- 4.9 to 2.5 +/- 3.3 attacks for 2 weeks and nitroglycerin consumption from 2.6 +/- 2.8 to 1.3 +/- 1.7 tablets for 2 weeks compared with patients receiving the placebo, but the reduction was not statistically significant. Exercise time increased from 345 +/- 102 seconds with placebo to 406 +/- 114 seconds during CoQ10 treatment (p less than 0.05). The time until 1 mm of ST-segment depression occurred increased from 196 +/- 76 seconds with placebo to 284 +/- 104 seconds during CoQ10 treatment (p less than 0.01). During the exercise test, ST-segment depression, heart rate and pressure-rate product at the same and at the maximal workload showed no significant difference between patients after placebo and CoQ10 administration. The average CoQ10 plasma concentration increased from 0.95 +/- 0.48 microgram/ml to 2.20 +/- 0.98 microgram/ml after CoQ10 treatment. This increase was significantly related to the increase in exercise duration (r = 0.68, p less than 0.001). Only 1 patient had a loss of appetite, but continued therapy. This study suggests that CoQ10 is a safe and promising treatment for angina pectoris.