Eicosapentaenoic acid (EPA) is an omega-3 polyunsaturated fatty acid found primarily in fish oils. Its use in supporting or treating angina is primarily based on scientific rationale rather than strong clinical evidence. EPA is known to have anti-inflammatory, anti-thrombotic, and lipid-lowering properties, all of which are theoretically beneficial in the management of cardiovascular diseases, including angina pectoris. Several epidemiological and interventional studies have suggested that higher intake of omega-3 fatty acids is associated with reduced cardiovascular events, but direct studies on EPA specifically for angina are limited.

Some small trials and observational studies have reported improvements in endothelial function and reductions in cardiac ischemic events with EPA supplementation, which could potentially benefit patients with angina. For example, omega-3 supplementation has been shown to reduce triglyceride levels and may stabilize atherosclerotic plaques, potentially reducing the frequency or severity of angina episodes.

However, large clinical trials have not conclusively demonstrated that EPA supplementation significantly improves clinical outcomes specifically for angina. Most authoritative guidelines do not recommend EPA solely for the treatment of angina, though it may be considered as part of a broader strategy for cardiovascular risk reduction. Thus, while there is some scientific basis for its use, the overall level of supporting evidence is modest.