Description

Trimetazidine HCl is a medication used to treat angina pectoris. It is classified as an anti-ischemic or metabolic agent, meaning it works by improving the energy efficiency of the heart muscle rather than by directly affecting heart rate or blood pressure. The “HCl” in its name denotes the hydrochloride salt form, which is used for stability and solubility.

Indications

Trimetazidine is primarily indicated for the symptomatic treatment of stable angina pectoris. It is typically used:

• As an add-on therapy for patients with stable angina who are not adequately controlled by or are intolerant to first-line anti-anginal therapies like beta-blockers or calcium channel blockers.

• To improve exercise capacity and reduce the frequency of angina attacks.

Mechanism of Action

Trimetazidine’s mechanism of action is unique because it modifies the metabolism of the heart muscle cells to make them more efficient at producing energy, particularly under ischemic conditions (when oxygen supply is limited).

1. Partial Fatty Acid Oxidation Inhibitor: Trimetazidine inhibits an enzyme called 3-ketoacyl-CoA thiolase, which is involved in the final step of fatty acid oxidation. In a healthy heart, fatty acids are the primary source of energy, but they require more oxygen to be metabolized than glucose.
2. Shifts Energy Metabolism: By partially blocking the oxidation of fatty acids, trimetazidine forces the heart muscle to rely more on glucose oxidation. Glucose metabolism is more efficient and requires less oxygen to produce the same amount of ATP (the energy currency of the cell).
3. Improved Myocardial Efficiency: This metabolic shift from fatty acid oxidation to glucose oxidation results in a more efficient use of the limited oxygen available to the heart muscle during an angina attack. This helps to maintain the energy levels of the heart cells, preventing the build-up of harmful byproducts and improving the heart’s ability to function under stress.
4. No Hemodynamic Effects: A key advantage of trimetazidine is that it provides anti-anginal effects without significantly affecting key hemodynamic parameters like heart rate, blood pressure, or cardiac contractility. This makes it a suitable option for patients who cannot tolerate the side effects of other anti-anginal drugs.