Figure 3.

A schematic illustration of the expected effects of tissue fibrosis on conduction in bundles of cardiomyocyte (red cylinders). (A) Normal tissue. (B) Fibrosis occurring parallel to cardiomyocyte-bundle sheaths (as would occur in reactive fibrosis). Longitudinal cell-to-cell connections are intact and longitudinal conduction is unaffected. (C) Fibrosis parallel to and across cardiomyocyte bundles, as would occur in reparative fibrosis. End-to-end connections are prevented by the physical separation resulting from replacement of dead cardiomyocytes by fibroblasts and fibrotic extracellular matrix proteins, producing local impairments in longitudinal conduction.