Purpose: The metabolic management of ischemic heart disease represents a promising new therapeutic approach for acute coronary syndromes. Trimetazidine has been suggested to exert anti-ischemic properties on myocardium without affecting myocardial oxygen consumption or supply. The aim of this study was to investigate whether the administration of trimetazidine, as an adjunct to conventional treatment, decreases QT dispersion in patients with acute myocardial infarction (AMI).
Methods and results: The study was prospective, randomized, double-blind and included 55 out of 86 consecutive patients aged < or = 80 years, admitted with a first AMI. Excluded from the study subjects with atrial fibrillation or pacing-rhythm, bundle branch block, pericardial or valvular heart disease or cardiogenic shock. Also were excluded patients treated with inotropic and antiarrhythmic agents, except for beta blockers. Enrolled patients were randomized into 2 groups: Trimetazidine group (n=29) and control group (n = 26). All patients were treated conventionally and, in addition, trimetazidine group patients were received trimetazidine 20 mg orally every 8 hours started after randomization and continued throughout hospitalization. The QT and QTc (corrected QT) dispersion were measured manually on 3 and 7 post-AMI days. The mean values of QT and QTc dispersion were significantly lower in trimetazidine group on both days, compared to control group: Day 3, QTD = 52+/-24 ms vs 68+/-30 ms (p = 0.034), QTcD = 52+/-21 ms vs 75+/-34 ms (p = 0.004). Day 7, QTD = 39+/-17 ms vs 60+/-20 ms (p < 0.0001), QTcD 40+/-17 ms vs 62+/-20 ms (p < 0.0001). Between days 3 and 7 the mean values of QT (p = 0.003) and QTc dispersion (p = 0.002) were decreased significantly only in trimetazidine group. An analysis with respect to the use of thrombolysis revealed that trimetazidine sub-groups had lower QT and QTc dispersion mean values on day 7, both in patients treated (p < 0.05) and non-treated (p = 0.001) with thrombolysis.
Conclusions: It is concluded that trimetazidine decreases QT and QTc dispersion after acute myocardial infarction. Further investigation is needed to evaluate the mechanism and the clinical implications of this effect.