TRIMETAZIDINE - A NEW CONCEPT IN THE TREATMENT OF ANGINA - COMPARISONWITH PROPRANOLOL IN PATIENTS WITH STABLE ANGINA

1 Trimetazidine has a direct anti-ischaemic effect on the myocardium w ithout altering the rate x pressure product or coronary blood flow. 2 The effects of trimetazidine (20 mg three times daily) were compared w ith those of propranolol (40 mg three times daily) in a double-blind p arallel group multicentre study in 149 men with stable angina. 3 Repro ducibility of exercise performance was verified during a 3 week run-in placebo washout period. All patients had > 1 mm ST-depression on exer cise test. 4 After 3 months, similar anti-anginal efficacy was observe d between the trimetazidine (n = 71) and propranolol (n = 78) groups. No significant differences were observed between trimetazidine and pro pranolol as regards anginal attack rate per week (mean difference P - TMZ: -2; 95% CI: -4.4, 0.5) and exercise duration (mean difference P - TMZ: 0 s; 95% CI: -33, 34) or time to 1 mm ST segment depression (mea n difference P - TMZ: 13 s; 95% CI: -24, 51). Heart rate and rate x pr essure product at rest and at peak exercise remained unchanged in the trimetazidine group but significantly decreased with propranolol (P < 0.001 in all cases). With both drugs there was a trend to decreased is chaemic episodes in the 46% patients who experienced ambulatory ischae mia on Holter monitoring. Six patients stopped trimetazidine and 12 pr opranolol. Of these, five in each group were withdrawn because of dete rioration in cardiovascular status. 5 The results suggest that trimeta zidine and propranolol at the doses studied have similar efficacy in p atients with stable angina pectoris. The unchanged rate x pressure pro duct suggests that the mechanism of action of trimetazidine is not pri marily reduction in energy demand.