Meldonium ( Idrinol ) was effective when parenterally administered in a dose of 1000 mg/day for 10-14 days as part of combination therapy in the early post-infarction period , which showed up as clinical improvement , a significant reduction in the frequency of angina attacks and in the need to use nitroglycerin , a decrease in the number of arrhythmia episodes , and its normalizing effect of HRV .