Erythrocyte Deformability Is Impaired in Patients with Nonvalvular Atrial Fibrillation

Abstract

Erythrocytes show biconcaved disc configuration and passive bending deformation in microcirculation where er ythrocytes’ diameter is greater than the minimal diameter of microvasculature. Therefore, the whole cell deformability of circulating erythrocytes is a major determinant of fluent microcirculation. This deformability is reported to be impaired in patients with various systemic as well as cardiac diseases such as hypertension, diabetes and atrial fibrillation (AF) which is prevalent in this country where senescence is rapidly growing. This common arrhythmia is characteristic in that AF is age-dependent, progressive from paroxysmal to persistent and finally permanent form, and associated with ischemic cerebral thromboembolism, i.e., cardiogenic stroke is one of the major complications of AF. This devastating complication is likely to occur in AF patients with senescence, hypertension, diabetes, heart failure and previous embolic episodes. Many of these factors impair the erythrocyte deformability. In our multivariate analyses, AF is the greatest contributing factor of impaired erythrocyte deformability in outpatients visiting our hospital, suggesting that many factors impairing this deformability are accumulated in AF patients. Inflammatory endocardial surface and stagnant blood flow with hemoconcentration in fibrillating left atria establish the Virchow’s triad leading to thrombogenesis. However, direct relationship between the erythrocyte deformability and ischemic stroke in AF patients remains to be elucidated.