Recently, researchers have paid attention to the development of new products such as supplements food and nutraceuticals for identify and develop integrative therapies to be used in cardiovascular disease. As suggested by literature, some nutritional components (creatine, ribose) can enhance the fundamental energy levels for the functioning of the heart muscle and can enhance the body's antioxidant capacity through the reduction in free radicals activity, one of the main pathogenic mechanisms of these diseases. In this context, the investigators have developed a research with the principal purpose to establish whether a supplement of creatine and ribose can improve the total work capacity during exercise in a population of patients with known ischemic heart disease.

The investigators will enroll patients with previous acute coronary syndrome treated for at least 30 days by hospital discharge. The treatment regimen of all patients will be optimized in accordance with European Society of Cardiology guidelines. Standardized pharmacological treatment during cardiac rehabilitation period will include administration of angiotensin converting enzyme inhibition (ACE), beta-blockers and antiplatelet blockers. Furthermore, in order to keep patients free from angina symptoms, in some cases calcium channel blockers and/or nitrates will be used. The investigators will randomize participants into two groups, one receiving treatment Creatine, D-Ribose, B1 Vitamin, and B6 vitamin, and one receiving placebo in a double blind study design, for 6 months.

Inclusion Criteria:

• All patients presented acute coronary syndrome treated with at least 30 days by hospital discharge

Exclusion Criteria:

• oncological diseases
• stable atrial fibrillation
• stent in the common core
• patients who are not able to perform physical activities
• patients with documented sustained ventricular arrhythmias
• pregnant women

Double blind study design. The dietary supplement of Creatine, D-Ribose, B1 Vitamin, and B6 vitamin will come in the form of water-soluble powder in sachets of 4 grams. Each sachet contains 1 gram of Creatine, 2.5 grams of D-Ribose, 0.33 mg of B1 vitamin and 0.42 mg of B6 vitamin. The same administration will come for placebo group with the inert product sachets consisting of starch powder.