Septal circumferential strain pattern in patients with non-LBBB (A, B) and healthy (C) subjects. All subjects had normal contraction patterns with maximum negative circumferential strain reached in the septum earlier than in the inferolateral wall. A. Patient with interventricular conduction delay and QRS duration of 146 ms. B. Patient with a normal QRS duration of 98 ms. C. Healthy subject with a normal QRS duration of 98 ms. AS = anteroseptum, IS = inferoseptum, IL = inferolateral wall. AVO = aortic valve opening. AVC = aortic valve closure.