Short-term effects of omega-3 fatty acids on exercise stress test parameters, angina and lipoproteins

The short-term effects of omega-3 fatty acids on exercise test parameters in patients with known coronary artery disease are poorly defined. Therefore, we administered a preparation containing 5.4 g of eicosapentaenoic acid and 3.6 g docosahexaenoic acid to 8 patients in a random order, double-blind, crossover design. The patients were given either fish oil or a vegetable oil control for 6 wk and then crossed over to the other treatment for a second 6-wk period, after a 2-wk wash-out interval. Exercise test parameters, angina frequency, and lipoprotein composition were measured at baseline and at the end of each trial phase. No significant changes were found in resting or peak exercise heart rate or double product, exercise duration or ischemic electrocardiographic changes at peak exercise. Angina frequency and sublingual nitroglycerin usage did not change during either the fish oil or the control oil phase. Plasma triglyceride levels decreased significantly with fish oil treatment and HDL cholesterol levels rose slightly. Total and LDL cholesterol levels were unchanged. We conclude that relatively high dose, short-term administration of omega-3 fatty acids does not alter exercise test parameters.