People who have had stents placed to open clogged coronary arteries may benefit from taking omega-3 fatty acids along with aspirin and Plavix to prevent future heart attacks. So says a new European study.

A stent is a small tube placed in a clogged coronary artery after a catheter procedure to keep it open and allow normal blood flow to the heart. Stent placement increases the risk of blood clot formation at the site where the stent is placed which can block the flow of blood to the heart resulting in a heart attack. Blood thinners are routinely given after stent placement to reduce this risk.

When compared to the control group, the patients treated with omega-3s produced less thrombin, a clotting factor, and formed clots with a structure that made them easier to disrupt.

Omega-3 fatty acids have blood thinning properties. People who have existing coronary artery disease are encouraged to consume more foods rich in omega-3 fatty acids including fatty fish such as salmon, mackerel, herring, lake trout, sardines, and albacore tuna. According to the American Heart Association, "Research has shown that omega-3 fatty acids decrease risk of arrhythmias (abnormal heartbeats), which can lead to sudden death. Omega-3 fatty acids also decrease triglyceride levels, slow growth rate of atherosclerotic plaque, and lower blood pressure (slightly)."

This new study looked at the effect of omega-3 fatty acids in pill form on people treated with blood-thinning drugs after having a stent placed. Conducted at John Paul II Hospital in Krakow, Poland, the study, led by Dr. Grzegorz Gajox and colleagues, had 54 participants who were on average about 63 years old. All previously had clogged arteries opened by a catheter procedure and stents placed to keep the vessels open. All of the patients were on standard medical therapy after stent placement which included a daily aspirin and the blood thinning drug, Plavix, for four weeks after the stent was placed.

The Omega-PCI Study, a double-blind, placebo-controlled trial, was designed to determine what effects omega-3s might add to the effects of aspirin and Plavix. For the study, 30 patients were randomly assigned to take the pill form of omega-3s (1,000 milligrams of EPA and DHA) every day, and the other 24 patients received a placebo. When compared to the control group, the patients treated with omega-3s produced less thrombin, a clotting factor, and formed clots with a structure that made them easier to disrupt. This could prove important in protecting patients with stents from having future heart attacks.

The researchers pointed out that these findings could not be extended to other groups of people such as those who are healthy, those with an increased risk of coronary artery disease, or those who do not take blood-thinning drugs. Also, important to note is that fish oil is an adjunct treatment, not a replacement for blood-thinning drugs.

The researchers are planning a larger follow-up study that will include outcomes and continue indefinitely.

The study was published in the May 26, 2011 issue of Arteriosclerosis, Thrombosis and Vascular Biology: Journal of the American Heart Association