The process that mediates interactions between an SA node cardiomyocyte and its surroundings that contributes to the process of the SA node cardiomyocyte communicating with an atrial cardiomyocyte in cardiac conduction. Encompasses interactions such as signaling or attachment between one cell and another cell, between a cell and an extracellular matrix, or between a cell and any other aspect of its environment.
SA node cardiac muscle cell to atrial cardiac muscle cell communication