Intracoronary Doppler blood flow velocity profile showing the characteristic “finger-tip”-like flow velocity acceleration during early diastole (single arrow)followed by a plateau phase at mid-to-late diastole (arrows in A and B). During systole, there is almost no flow within the bridged segment, but a retrograde flow phenomenon occurs at the entry site of the myocardial bridge (arrows in A). During rapid atrial pacing, absolute diastolic flow velocities are increased, and the duration of the plateau phase is reduced owing to shortened diastole (C). Reproduced from Schwarz et al. (13), with permission.