_______ have been shown to decrease the risk of arrhythmias and fatal heart disease and decrease progression of coronary atherosclerosis in individuals with diagnosed coronary heart disease.

Omega-3 fatty acids are recognized for their significant cardiovascular benefits, particularly for individuals diagnosed with coronary heart disease. Research has demonstrated that omega-3 fatty acids can help decrease the risk of arrhythmias and reduce the likelihood of fatal heart disease. They achieve this by promoting healthy heart rhythms and lowering triglyceride levels in the blood, which can lead to improved heart health overall.

Additionally, omega-3 fatty acids have a positive effect on inflammation and can slow down the progression of coronary atherosclerosis by reducing plaque buildup in the arteries. This contributes to better blood flow and reduces the risk of serious cardiovascular events.

In contrast, omega-6 fatty acids do not demonstrate the same protective effects against heart disease and may, in excess, promote inflammation. Antioxidants play a role in reducing oxidative stress but are not directly linked with the specific outcomes cited in the question concerning heart disease and arrhythmias. Plant stanols are effective in lowering cholesterol levels but do not have a direct relationship with reducing the risk of arrhythmias or heart disease progression in the context described.