Variability in Tissue Doppler Echocardiographic Measures of Dyssynchrony Is Reduced With Use of a Larger Region of Interest

Using a 30 × 6 mm ROI instead of a 6 × 6 mm ROI to quantify tissue Doppler dyssynchrony reduces variability by 47% and diagnostic inconsistency by 44%. The authors recommend using a 30 × 6 mm ROI in future trials to minimize variability.