ION CHANNEL REMODELING AND ATRIAL FIBRILLATION: CLINICAL ASPECTS

摘要

The progression to sustained atrial fibrillation depends on electrical remodeling, i.e. a progressive decrease of the effective refractory period. It also relates to structural remodeling. These processes go hand in hand.Electrical remodeling induced by AF is due to intracellular calcium overload. This leads to shortening of the atrial action potential and loss of action potential rate adaptation. These electrical changes are reversible once atrial fibrillation has disappeared. In the mean time however, calcium overload may have led to activation of intracellular proteases like calpains which cleave cellular proteins of the cytoskeleton, channel proteins and the contractile elements. In this way the high atrial rate during atrial fibrillation may secondarily lead to structural remodeling.