The efficacy of propionyl-
L-carnitine in increasing walking capacity in patients with
peripheral arterial disease is primarily due to the metabolic effect of the
drug, but a direct vasoactive action is also hypothesized. Muscular and subcutaneous blood flow of lower limbs were separately evaluated using the 133-Xenon washout technique in 10 patients with
peripheral arterial disease of moderate degree, before and after 8-days of treatment with propionyl-
L-carnitine (1 g orally b.i.d.).
After treatment, muscular blood flow slightly increased, from 10.7 +/- 13.4 to 14.1 +/- 14.0 ml kg-1 min-1. This increase was not statistically significant (T = -1.6568, P = 0.136). Subcutaneous blood flow was not affected by the treatment (from 26.2 +/- 16.9 to 26.1 +/- 12.5 ml kg-1 min-1, T = 0.0141, P = 0.95). In conclusion, in patients with
peripheral arterial disease, short-term
therapy with propionyl-
L-carnitine had no clinical significant effect on muscular and subcutaneous blood flow of the lower limbs. Therefore, this study suggests that the beneficial effect of this
drug on the walking capacity of patients with
peripheral arterial disease is not due to a direct vasoactive action.
Oral administration of propionyl-
L-carnitine was found to be safe, as it did not cause any change in heptic, renal or metabolic functional parameters.