The team says that omega-3 fatty acids, whether animal or plant-based, contributes to heart health and function as demonstrated by the sample size’s lower overall risk of complications post heart attack.
"Incorporating marine and vegetable omega-3s into the diet of patients at risk of cardiovascular disease is an integrative strategy for improving both their quality of life and prognosis if they suffer a heart attack," says Antoni Bayés, clinical director of Cardiology at Germans Trias.
In the long-term, Coronary Artery Disease (CAD) patients are at risk of secondary cardiovascular (CV) events that pose a significant burden beyond the acute-care time period for heart attack survivors.
Diets high in seafood have been strongly associated with a lower risk of fatal CV events, particularly sudden cardiac death.
Membrane accumulation of the omega-3 fatty acid Eicosapentaenoic Acid (EPA) is thought to play a role in beneficial cardiac effects linked with long-term consumption of fatty fish and fish oils.
In addition to promoting more efficient myocardial oxygen consumption, membrane EPA protects against a variety of heart stressors.
Research has led to the notion that EPA enrichment in cardiac membranes, due to sustained consumption of fatty fish or fish oils, might limit the degree of myocardial damage in the event of a heart attack.
Researchers from the Germans Trias i Pujol Hospital and Research Institute (IGTP) and the Hospital del Mar Medical Research Institute (IMIM) used data from 950 patients.
The omega-3 levels in the blood of these patients were noted when they were admitted to hospital following a heart attack as a measure of the quantity and types of fats consumed prior to the heart attack.
The team made a note of not only Eicosapentaenoic acid (EPA) levels in the blood but also alpha-linolenic acid (ALA) levels.
This omega-3 fat, found in walnuts and soybeans, did not compete with EPA but was complementary.
While high levels of EPA are associated with a lower risk of hospital readmission from cardiovascular causes, higher levels of ALA are associated with a reduced risk of death.
The patients were monitored for three years after discharge, where researchers made the link between high levels of omega-3 in the blood at the time of the heart attack and a lower risk of complications.
Mechanism of action
In suggesting a cardioprotective mechanism of these fats, the team suggests that consumption of foods rich in omega-3 fatty acids enriches cardiomyocyte membranes partially displacing arachidonic acid.
When a heart attack occurs, the decreased blood flow and oxygen to the heart muscle triggers fatty acid breakdown from cardiac muscle membranes.
Released fatty acids are then converted to oxylipins, which can promote inflammation. Released arachidonic acid also promotes inflammation that amplify heart muscle damage.
“In contrast, cleaved omega-3 fatty acids are converted to anti-inflammatory eicosanoids, hence limiting ischemic-associated myocardial damage. This translates into a decreased risk of long-term cardiac events,” the study suggests.
In closing, the team recommends that for cardiac patients or patients with CV risk factors, consuming sources of marine and vegetable omega-3 fatty acids might serve as an “integrative strategy for improving the quality of life and life expectancy in the event they experience a heart attack.
“These results might also explain, in part, the paradoxical observation that countries with customarily high seafood intake, such as Japan and Spain, have lower CAD mortality rates, despite a high prevalence of CV risk factors.”