Fig. 1
Examples of strain curves of the septal (solid black curve) and lateral wall (dashed grey curve) derived with vendor dependent and independent speckle tracking echocardiography software of two patients. Aortic valve closure (AVC) is marked with a thin solid grey line. Philips was used for echocardiographic examination in patient 1 (panel A & C), and GE was used for patient 2 (panel B & D). Corresponding ECGs are shown below (panel E & F). SRSsept is marked red and lateral wall pre-stretch is marked blue in patient 2. AVC: aortic valve closure, MVC: mitral valve closure, SL-delay: septal to lateral wall delay, SRSsept: septal systolic rebound stretch, SSI: systolic stretch index, TTPfirst: time to first peak shortening, TTPmax: time to maximal peak shortening