Semi-automatic analysis of left atrial (LA) strain. The solid line on the graph represents changes in the LA strain during the cardiac cycle. The dotted white arrows represent three components of the LA strain: SR, reservoir strain (left atrial elongation during left ventricular systole); SCD, conduit strain (left atrial shortening during early left ventricular diastole); SCT, contraction strain (left atrial shortening during atrial contraction)