To-and-fro pattern: an indication of flow competition or a sign of incompetent coronary anastomosis?

To-and-fro pattern in pulse Doppler wave form has been considered a sign of flow competition at the coronary anastomosis. However, this flow pattern is not sufficient to judge whether there is no construction errors in the anastomosis itself. We report a usefulness of the high-frequency ultralinear transducer when used with pulse Doppler because it allows the visualization of the shapes of the anastomosis and each vessel, quantification of the flow, and elucidation of flow characteristics. This transducer can be applied to the management of suspected flow competition because, with pulse Doppler waveforms of graft flow and color Doppler images, it allows the detection of the diastolic-dominant flow pattern, good anastomotic shape, and smooth flow in the graft and the target vessel after the native vessel is clamped.