Colour coded strain rate curved M-modes (top) and strain curves (middle) in 2 myocardial segments both showing post-systolic shortening (PSS). Left panel: physiologic PSS in an apical septum of a normal heart. Peak systolic strain exceeds −18% and PSS is less than 20% of systolic shortening. Right panel: pathologic PSS in a partially scarred segment post infarction. Peak systolic strain is reduced to −10.1% while post systolic strain is increased to 39% of systolic strain. AVC - Aortic valve closure; MVO - mitral valve opening. (modified from Voigt et al. , with permission).