['Associated left ventricular structures may play a role in progression and recurrence of discrete subaortic stenosis. The availability of a new 3D echocardiography tool, multiplanar review (MPR), allows comprehensive analysis of datasets in infinite planes, and detailed examination of anatomy. We sought to evaluate the role of MPR in defining the morphology of subaortic stenosis.', 'Consecutive patients underwent detailed 2 and 3D echocardiographic examination using MPR.', 'Sixteen patients aged 0.7-15.9 years (median 4.57) with diagnosis as follows: isolated subaortic stenosis in nine, additional defects in seven (coarctation of aorta, VSD, mitral, or aortic stenosis). Position and extent of subaortic stenosis was clearly described by multiplanar review in all patients. Additional MPR findings were: abnormalities of mitral valve leaflet or chordal apparatus attachments (14 patients), abnormal ventricular muscle band (11), abnormal increased aorto-mitral separation (two). The aortoseptal angle was significantly decreased in subaortic stenosis, mean 141 +/- 12 degrees , vs. normal subjects, mean 153 +/- 6 degrees , P = 0.02. Surgical findings correlated well with MPR findings.'] Does multiplanar review analysis of three-dimensional echocardiographic datasets give new insights into the morphology of subaortic stenosis?