A multicenter, double-blind study was performed in 46 patients with stable effort angina pectoris on maintenance doses of long-acting nitrate in order to evaluate the effect of levocarnitine chloride (LC-80) tablets, containing 200 mg of levocarnitine chloride, on exercise tolerance. Multistage treadmill exercise testing was performed according to the modified Bruce protocol at the pre-treatment period and after 4 and 8 wk of oral daily doses of 1800 mg of LC-80 or placebo therapy.
In the pre-treatment period, there were no significant differences in treadmill exercise duration, time to the onset of angina, pressure-rate product (PRP), and ST deviation between the placebo and LC-80 groups.
The time to the onset of angina was significantly longer after 4 (P<0.05) and 8 wk (P<0.01) of LC-80 therapy than in the pre-treatment period and the increment in the time to the onset of angina was significantly greater (P<0.05) after 8 wk of LC-80 therapy as compared to placebo administration. In-exercise ST segment depression tended to be of lesser magnitude after 8 wk of LC-80 therapy than in the pretreatment period (P<0.1). Resting and in-exercise blood pressure, heart rate, and PRP were unaffected by LC-80.
In conclusion, the results of the present study suggest that LC-80 may improve exercise tolerance in patients with stable effort angina pectoris with no significant effects on the circulatory response to exercise, and the agent may be clinically employed as an adjunct to the conventional anti-anginal agent in the management of ischemic heart disease.