Mean TTPSD values in each software configuration, by group. Mean values are presented (±2 standard deviation) by group (36 patients in each). a) AP4 TTPSD; b) SAX-M TTPSD. An asterisk indicates a p-value < 0.05. There were many differences in mean AP4 and SAXM TTPSD for QLAB 10.5, QLAB 10.8, and TomTec at each frame rate and smoothness setting for all of the subgroups AP4 (Apical four chamber view), LFR (Low frame rate), LS (Low quantification smoothness setting), HS (High quantification smoothness setting), MS (Medium quantification smoothness setting), SAXM (Short Axis Mid papillary muscle). Dark gray bars (group 1) patients have normal hearts; white bars (group 2) patients have ventricular paced rhythms; light gray bars (group 3) patients have flattened ventricular septum.