Adding omega 3 fish oils to standard treatment for patients with symptomatic heart failure could reduce mortality and lower admission rates for cardiovascular problems, according to results from the GISSI-HF study.

The GISSI-HF trial assessed the impact of omega 3 fatty acids and statin therapy in addition to standard medical therapy in patients with symptomatic heart failure.

In one arm of the study almost 7,000 patients were enrolled with chronic heart failure irrespective of cause or left ventricular ejection fraction. They were randomised to either 1g/day of omega 3 polyunsaturated fatty acids or placebo. Patients were followed up for nearly four years, with co-primary endpoints of death and a composite of death or admission to hospital for cardiovascular problems.

The results showed a modest but significant reduction in mortality in the omega 3 group with 955 deaths vs 1,014 in the placebo group (HR 0.91; p=0.04). A similar trend was seen for the composite endpoint of death or admission for cardiovascular problems with 1,981 events in the omega 3 group vs 2,053 in the placebo group (HR 0.92; p=0.01).

A further arm of the GISSI-HF trial looked at the role of statins in heart failure. In this part of the study, 4,500 patients were randomised to either rosuvastatin 10 mg daily or placebo. As in other studies, such as CORONA, there was no benefit from statin therapy on either mortality (HR 1.00; p=0.9) and the composite of death/admission for cardiovascular problems (HR 1.01; p=0.9).

Therefore, it would appear that the addition of omega 3 fish oils to standard therapy for patients with symptomatic heart failure could provide a small advantage in terms of mortality and admission to hospital for cardiovascular reasons. The exact mechanism of action remains unknown but could be mediated via effects on endothelial activation, cytokine production, platelet aggregation, blood pressure, heart rate, ventricular function, and autonomic tone.

From a practical perspective I would not discourage heart failure patients from using omega 3 fish oils but would not initiate statin therapy in this group.