Combination of trimetazidine with nifedipine in effort angina

Trimetazidine and Other Metabolic Modifiers

Treatment goals for people with chronic angina should focus on the relief of symptoms and improving mortality rates so the patient can feel better and live longer. The traditional haemodynamic approach to ischaemic heart disease was based on the assumption that increasing oxygen supply and decreasing oxygen demand would improve symptoms. However, data from clinical trials, show that about one third of people continue to have angina despite a successful percutaneous coronary intervention and medical therapy. Moreover, several trials on chronic stable angina therapy and revascularisation have failed to show benefits in terms of primary outcome (survival, cardiovascular death, all-cause mortality), symptom relief or echocardiographic parameters. Failure to significantly improve quality of life and prognosis may be attributed in part to a limited understanding of ischaemic heart disease, by neglecting the fact that ischaemia is a metabolic disorder. Shifting cardiac metabolism from free fatty acids towards glucose is a promising approach for the treatment of patients with stable angina, independent of the underlying disease (macrovascular and/or microvascular disease). Cardiac metabolic modulators open the way to a greater understanding of ischaemic heart disease and its common clinical manifestations as an energetic disorder rather than an imbalance between the demand and supply of oxygen and metabolites.

WITHDRAWN: Trimetazidine for stable angina

BACKGROUND

Patients with stable angina not controlled by monotherapy with nitrates, beta blockers, or calcium channel blockers are often treated with combinations of these drugs. There may be adverse effects from, or contraindications to, the use of combinations. In low risk groups, medical treatment appears to be as good an option as percutaneous transluminal coronary angioplasty in terms of averting myocardial infarction, death, or subsequent revascularization. Revascularization procedures are too costly or inaccessible for many patients in developing countries therefore effective and safe medical treatment is needed. Trimetazidine is a less well known anti-anginal drug that controls myocardial ischaemia through intracellular metabolic changes. Trimetazidine has been reported, in some studies, to be better tolerated than combined anti-anginal therapy; however it is not considered in published guidelines.

OBJECTIVES

To determine the efficacy and tolerability of trimetazidine in patients with stable angina.

SEARCH METHODS

We searched The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, LILACS and SCISEARCH, without language restriction, from inception to October 2003. Experts in the field were contacted to locate unpublished studies.

SELECTION CRITERIA

Randomised studies comparing trimetazidine with placebo, or other anti-angina drug in adults with stable angina.

DATA COLLECTION AND ANALYSIS

Two reviewers independently applied the inclusion criteria, assessed trial quality and extracted data.

MAIN RESULTS

Twenty-three studies (1378 patients) met the inclusion criteria. There was a paucity of information about mortality, cardiovascular events and quality of life. Trimetazidine, compared with placebo, reduced the number of weekly angina attacks ( mean difference -1.44, 95% CI -2.10 to -0.79; P < 0.0001), reduced weekly nitroglycerin tablet consumption (95% CI -1.47 to -2.20, -0.73; P < 0.0001) and improved exercise time to 1 mm segment depression (P = 0.0002). Four small trials (263 patients) compared trimetazidine against other anti-anginal agents. One favoured trimetazidine over nitrates. Three tended to favour alternative regimens but with confidence intervals consistent with both major increases and decreases in frequency of angina episodes. In this subgroup, adverse events were considered in 5 trials (448 patients) and totals of 2 versus 12 drop outs due to adverse events were observed in the trimetazidine and alternative regimens respectively, but this was mostly driven by a single trial.

AUTHORS' CONCLUSIONS

Trimetazidine is effective in the treatment of stable angina compared with placebo, alone or combined with conventional anti-anginal agents. Trimetazidine may result in fewer dropouts due to adverse events. Large, long term trials comparing trimetazidine with other anti-anginal drugs assessing clinically relevant important outcomes are required to establish its role in clinical management.

The effects of chronic trimetazidine treatment on mechanical function and fatty acid oxidation in diabetic rat hearts

Clinical and experimental evidence suggest that increased rates of fatty acid oxidation in the myocardium result in impaired contractile function in both normal and diabetic hearts. Glucose utilization is decreased in type 1 diabetes, and fatty acid oxidation dominates for energy production at the expense of an increase in oxygen requirement. The objective of this study was to examine the effect of chronic treatment with trimetazidine (TMZ) on cardiac mechanical function and fatty acid oxidation in streptozocin (STZ)-diabetic rats. Spontaneously beating hearts from male Sprague–Dawley rats were subjected to a 60-minute aerobic perfusion period with a recirculating Krebs–Henseleit solution containing 11 mmol/L glucose, 100 μU/mL insulin, and 0.8 mmol/L palmitate prebound to 3% bovine serum albumin (BSA). Mechanical function of the hearts, as cardiac output × heart rate (in (mL/min)·(beats/min)·10–2), was deteriorated in diabetic (73 ± 4) and TMZ-treated diabetic (61 ± 7) groups compared with control (119 ± 3) and TMZ-treated controls (131 ± 6). TMZ treatment increased coronary flow in TMZ-treated control (23 ± 1 mL/min) hearts compared with untreated controls (18 ± 1 mL/min). The mRNA expression of 3-ketoacyl-CoA thiolase (3-KAT) was increased in diabetic hearts. The inhibitory effect of TMZ on fatty acid oxidation was not detected at 0.8 mmol/L palmitate in the perfusate. Addition of 1 μmol/L TMZ 30 min into the perfusion did not affect fatty acid oxidation rates, cardiac work, or coronary flow. Our results suggest that higher expression of 3-KAT in diabetic rats might require increased concentrations of TMZ for the inhibitory effect on fatty acid oxidation. A detailed kinetic analysis of 3-KAT using different concentrations of fatty acid will determine the fatty acid inhibitory concentration of TMZ in diabetic state where plasma fatty acid levels are increased.

Trimetazidine for stable angina

BACKGROUND

Patients with stable angina not controlled by monotherapy with nitrates, beta blockers, or calcium channel blockers are often treated with combinations of these drugs. There may be adverse effects from, or contraindications to, the use of combinations. In low risk groups, medical treatment appears to be as good an option as percutaneous transluminal coronary angioplasty in terms of averting myocardial infarction, death, or subsequent revascularization. Revascularization procedures are too costly or inaccessible for many patients in developing countries therefore effective and safe medical treatment is needed. Trimetazidine is a less well known anti-anginal drug that controls myocardial ischaemia through intracellular metabolic changes. Trimetazidine has been reported, in some studies, to be better tolerated than combined anti-anginal therapy; however it is not considered in published guidelines.

OBJECTIVES

To determine the efficacy and tolerability of trimetazidine in patients with stable angina.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, LILACS and SCISEARCH, without language restriction, from inception to October 2003. Experts in the field were contacted to locate unpublished studies.

SELECTION CRITERIA

Randomised studies comparing trimetazidine with placebo, or other anti-angina drug in adults with stable angina.

DATA COLLECTION AND ANALYSIS

Two reviewers independently applied the inclusion criteria, assessed trial quality and extracted data.

MAIN RESULTS

Twenty-three studies (1378 patients) met the inclusion criteria. There was a paucity of information about mortality, cardiovascular events and quality of life. Trimetazidine, compared with placebo, reduced the number of weekly angina attacks ( mean difference -1.44, 95% CI -2.10 to -0.79; P < 0.0001), reduced weekly nitroglycerin tablet consumption (95% CI -1.47 to -2.20, -0.73; P < 0.0001) and improved exercise time to 1 mm segment depression (P=0.0002). Four small trials (263 patients) compared trimetazidine against other anti-anginal agents. One favoured trimetazidine over nitrates. Three tended to favour alternative regimens but with confidence intervals consistent with both major increases and decreases in frequency of angina episodes. In this subgroup, adverse events were considered in 5 trials (448 patients) and totals of 2 versus 12 drop outs due to adverse events were observed in the trimetazidine and alternative regimens respectively, but this was mostly driven by a single trial.

AUTHORS' CONCLUSIONS

Trimetazidine is effective in the treatment of stable angina compared with placebo, alone or combined with conventional anti-anginal agents. Trimetazidine may result in fewer dropouts due to adverse events. Large, long term trials comparing trimetazidine with other anti-anginal drugs assessing clinically relevant important outcomes are required to establish its role in clinical management.

Metabolic therapy in the treatment of ischaemic heart disease: the pharmacology of trimetazidine

The primary result of myocardial ischaemia is reduced oxygen consumption and adenosine triphosphate (ATP) formation in the mitochondria, and accelerated anaerobic glycolysis, lactate accumulation and cell acidosis. Classic pharmacotherapy for demand-induced ischaemia is aimed at restoring the balance between ATP synthesis and breakdown by increasing the oxygen delivery (i.e. with long acting nitrates or Ca2+ channel antagonist) or by decreasing cardiac power by reducing blood pressure and heart rate (i.e. with beta-blocker or Ca2+ channel antagonist). Animal studies show that fatty acids are the primary mitochondrial substrate during moderate severity myocardial ischaemia, and that they inhibit the oxidation of carbohydrate and drive the conversion of pyruvate to lactate. Drugs that partially inhibit myocardial fatty acid oxidation increase carbohydrate oxidation, which results in reduced lactate production and a higher cell pH during ischaemia. Trimetazidine (1-[2,3,4-trimethoxibenzyl]-piperazine) is the first and only registered drug in this class, and is available in over 90 countries world-wide. Trimetazidine selectively inhibits the fatty acid beta-oxidation enzyme 3-keto-acyl-CoA dehydrogenase (3-KAT), and is devoid of any direct haemodynamic effects. In double-blind placebo-controlled trials trimetazidine significantly improved symptom-limited exercise performance in stable angina patients when used either as monotherapy or in combination with beta-blockers or Ca2+ channel antagonists. Given available evidence, trimetazidine is an excellent alternative to classic haemodynamic agents, and is unique in its ability to reduce symptoms of angina when used in patients resistant to a haemodynamic treatment as vasodilators, beta-blockers or Ca2+ channel antagonists.

Effects of trimetazidine on clinical symptoms and tolerance of exercise of patients with syndrome X: a preliminary study

BACKGROUND

Trimetazidine diminishes angina and improves tolerance of exercise of patients with ischemic heart disease, and has no influence on blood pressure and heart rate.

OBJECTIVE

To determine the effect of trimetazidine on angina symptoms and exercise tolerance in patients with syndrome X.

METHODS

We investigated the effect of trimetazidine on the clinical symptoms and tolerance of exercise of 34 patients (20 women and 14 men, aged 32-60 years) with syndrome X (angina pectoris, positive result of exercise test, and normal coronary angiogram). The exercise test was performed before initiation of oral administration of trimetazidine therapy (20 mg three times a day) and 1 and 6 months thereafter.

RESULTS

We obtained negative results of exercise treadmill tests for four patients (11.76%) after 1 month and five patients (14.71%) after 6 months of trimetazidine treatment. There was also a decrease in the incidence of effort angina after 6 months of treatment (26 patients or 76.47% before treatment versus 13 patients or 38.23% after 6 months of treatment). The drug had no significant influence on the heart rate and blood pressure. The duration for which patients could exercise was significantly prolonged by 1 month (652.9 +/- 206.2 versus 563.4 +/- 190.4 s, P = 0.0047) and 6 months (650.3 +/- 207.8 s, P = 0.0094) of treatment with trimetazidine.

CONCLUSION

Treatment with trimetazidine decreases signs of angina during exercise and improves tolerance of exercise of patients with syndrome X.

Metabolic management of ischemic heart disease: clinical data with trimetazidine

The metabolic management of heart disease represents a promising new strategy for ischemic syndromes. This review focuses on the clinical studies performed with trimetazidine, a cellular anti-ischemic agent, either as monotherapy or in combination with other drugs. Acute and chronic administration of trimetazidine significantly increased total work, exercise duration, and time to 1-mm ST segment depression, without any change in heart rate, systolic blood pressure, or rate-pressure product at the same workload, as compared with placebo. Chronic administration studies have been performed comparing the anti-ischemic effects of trimetazidine with nifedipine or propranolol in patients with chronic stable angina. In these studies, the number of anginal attacks was significantly decreased in all groups. Ergometric results showed that trimetazidine increased duration of exercise, time to 1-mm ST segment depression, time to angina, and decreased ST segment depression at peak exercise similarly to propranolol or nifedipine treatment. Rate-pressure product at the same workload remained unchanged in the patients treated with trimetazidine in comparison with baseline treatment, suggesting no effect of the drug on oxygen demand, whereas it was decreased during treatment with nifedipine and propanolol, because of the hemodynamic activity of these drugs. The therapeutic value of adding trimetazidine to either calcium antagonists or beta blockers in patients with ischemic heart disease has also been demonstrated. Unlike classic anti-ischemic agents, treatment with trimetazidine is not accompanied by any modification in hemodynamic parameters, confirming the experimental data showing a unique mechanism of action via a direct effect on the ischemic myocardium.

Effects of trimetazidine on heart rate variability and left ventricular systolic performance in patients with coronary artery disease after percutaneous transluminal angioplasty

Fifty-one patients (mean age 51.6 +/- 7.1 years) with angiographically proven coronary artery disease (CAD) entered the study. In 26 patients (Group I), trimetazidine treatment started twenty-four hours after percutaneous transluminal coronary angioplasty (PTCA). Another 25 patients (Group II) without trimetazidine treatment were kept as controls. The groups were comparable by age, gender, risk factors of CAD, coronary anatomy, left ventricular performance, and heart rate variability indices at baseline state. Power spectral analysis of heart rate variability and two-dimensional and Doppler echocardiographic examinations were performed before PTCA, and twenty-four hours, ten days, thirty days, and three months after PTCA. A statistically significant improvement of left ventricular systolic performance (P < 0.001), augmentation of the parasympathetic band of heart rate variability (P < 0.001), and decline of P1/P2 ratio (P < 0.01) were evident in patients treated with trimetazidine, while no apparent changes were observed in controls. The intergroup analysis also showed marked difference between groups as recorded on the day 30 and month 3 of observation (P < 0.001). During follow-up period recurrences of angina pectoris and ischemia were registered in Group II, while no evidence of ischemia was discerned in Group I patients. In conclusion, trimetazidine modulates the autonomic control of heart rate, ie, reduces sympathetic overactivity and augments vagal influences, improves left ventricular contractility, and diminishes the clinical manifestations of ischemia in patients with CAD after PTCA.