Go to www.lef.org. Order their Mega GLA/DHA (the important Omega-3's) with Sesame Lignans. They are fanatic about the quality of products they sell. They cost a little more than other companies but it's worth it.
It's OTC. Lots of evidence that it prevents heart attacks in the first place and prevents reoccurence.
I order the majority of my supplements from lef.org because I trust the quality of their products.