Effect of trimetazidine on postischemic regional myocardial stunning in the halothane-anesthetized dog

Regulatory effects of trimetazidine in cardiac ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury is a tissue damage during reperfusion after an ischemic condition. I/R injury is induced by pathological cases including stroke, myocardial infarction, circulatory arrest, sickle cell disease, acute kidney injury, trauma, and sleep apnea. It can lead to increased morbidity and mortality in the context of these processes. Mitochondrial dysfunction is one of the hallmarks of I/R insult, which is induced via reactive oxygen species (ROS) production, apoptosis, and autophagy. MicroRNAs (miRNAs, miRs) are non-coding RNAs that play a main regulatory role in gene expression. Recently, there are evidence, which miRNAs are the major modulators of cardiovascular diseases, especially myocardial I/R injury. Cardiovascular miRNAs, specifically miR-21, and probably miR-24 and miR-126 have protective effects on myocardial I/R injury. Trimetazidine (TMZ) is a new class of metabolic agents with an anti-ischemic activity. It has beneficial effects on chronic stable angina by suppressing mitochondrial permeability transition pore (mPTP) opening. The present review study addressed the different mechanistic effects of TMZ on cardiac I/R injury. Online databases including Scopus, PubMed, Web of Science, and Cochrane library were assessed for published studies between 1986 and 2021. TMZ, an antioxidant and metabolic agent, prevents the cardiac reperfusion injury by regulating AMP-activated protein kinase (AMPK), cystathionine-γ-lyase enzyme (CSE)/hydrogen sulfide (H2S), and miR-21. Therefore, TMZ protects the heart against I/R injury by inducing key regulators such as AMPK, CSE/H2S, and miR-21.

The effects of trimetazidine on heart rate variability and signal-averaged electrocardiography in early period of acute myocardial infarction

BACKGROUND

Acute myocardial infarction (AMI) is accompanied by electrophysiological changes in cardiovascular system as well as those in autonomic cardiac control. Heart rate variability (HRV) is depressed due to increased sympathetic activity and/or decreased parasympathetic activity following AMI. Moreover, the frequency of ventricular late potentials (VLP) is increased due to the electrophysiological changes. Based on the hypothesis that the treatments increasing HRV and decreasing the frequency of VLP can improve the prognosis of AMI, we investigated the short-term effects of trimetazidine (TMZ) on HRV and VLP in patients with AMI.

METHODS

The study group consisted of 64 patients (men 49, mean age 55+/-12 years, range 26-70) suffering from first Q-wave AMI. Thirty-one of them were treated with conventional therapy (thrombolytic therapy, aspirin, beta-blocker, heparin and intravenous nitroglycerin) plus TMZ 20 mg tid. The remaining 33 patients served as controls. Holter monitorization between 24 and 48 h, echocardiography at average day 6 (range 4-7 days) and SAECG and sub-maximal exercise at average day 7 (range 6-9 days) were performed to all patients.

RESULTS

While HRV parameters reflecting parasympathetic activity (SDSD: 43+/-16 ms-35+/-13 ms, RMSSD: 34+/-14 ms-27+/-8 ms, HF: 7.8+/-5 ms(2) -4.3+/-4 ms(2), P<0.05) were of significantly higher levels in TMZ group, the low frequency component mainly reflecting sympathetic activity (LF: 10+/-6 ms(2)-10+/-5 ms(2), P>0.05) was similar in both groups. In addition, LF/HF ratio showing sympatho-vagal balance was significantly decreased in TMZ group (1.5-3.0, P=0.005). About VLP, the mean FQRS (105+/-8 ms-107+/-10 ms), LAS (28+/-10 ms-30+/-11 ms) and RMS-40 (34+/-15 microV-41+/-12 microV) were not different in both two groups (P>0.05).

CONCLUSION

Our results suggest that TMZ treatment causes changes in sympatho-vagal balance in favor of vagal activity by increasing parasympathetic activity in AMI at early period; however, no effect on VLP was observed.