Propionyl carnitine in stable effort angina.

The aim of this study was to investigate the anti-ischemic activity of propionyl carnitine (PC) in 18 informed, volunteer male patients, aged 37-70, suffering from a typical stable effort angina. The study design was randomized, balanced, crossover, and double blinded. The study lasted 75 days. In the first 15 days of washout the patients performed two maximal symptom-limited bicycle tests to verify the repeatability of the parameters examined. Then one group received PC for 30 days 500 mg three times a day, and the other group received placebo (PL) three times a day. At the end of 30 days the groups exchanged treatments. At the end of each period, 2 hours after the last oral administration, the patients performed a maximal symptom-limited bicycle exercise test with increased loads of 10 watts/min. No significant differences were observed between the two tests performed during the wash-out period, for a 1 mm ST-segment depression time, for the time to the end of exercise, and for the rate x pressure product at the same experimental time. The oral administration of PC in coronary patients increased both the 1 mm ST-segment depression time and the time to the end of exercise. Furthermore, the drug reduced the ischemic depression of ST at maximal common work and at maximal work. After PC, the rate x pressure product was not significantly different in relation to placebo at submaximal and maximal exercise. Thus PC seems to have an antiischemiclike effect, probably related to its metabolic activity.