Objective: Four decades ago, free fatty acids (FFA) were proved to enhance thrombus-formation. Recently, the role of FFA in thromboembolism has reemerged in the context of cardioembolic stroke. Therefore, we attempted to determine the role of FFA on the embolic risk in various potential sources of cardioembolism (PSCE) with the hypothesis that, if elevated FFA levels in stroke patients are associated with thrombogenesis, patients with a well-known high risk of embolic sources would have high FFA levels.
Methods: Data collected from two hospital-based stroke registries were analyzed to investigate the association between FFA and PSCE.
Results: A total of 2770 acute stroke patients, including 539 with cardioembolic stroke, were selected for analysis. FFA was an independent predictor for cardioembolism (OR 2.755, 95% CI 2.221-3.417, P<0.001) and significantly associated with fibrinogen and prothrombin time. Among the PSCE, atrial fibrillation, valvular heart disease, congestive heart failure with low ejection fraction, left atrial thrombus, left ventricular thrombus, left atrial smoke, and ventricular wall motion abnormality were independently associated with FFA. FFA level increased with the number of PSCE per patient. Significant correlation between the FFA ratio of PSCE to non-PSCE and the annualized thromboembolic event rate of each PSCE from the literature was noted (r2=0.5829, P<0.001).
Conclusions: Among acute stroke patients, FFA levels increase in proportion to the increase in thromboembolic risk for each PSCE. These results imply that enhanced thrombogenicity could be the main mechanism to explain the elevated FFA levels in patients with cardioembolic stroke.