Whole-heart magnetic resonance imaging of isolated subpulmonary stenosis accompanied by hypertrophic cardiomyopathy.

Isolated subvalvular pulmonary stenosis (ISPS) is a rare condition, and it is often accompanied by hypertrophic cardiomyopathy. However, diagnosis of ISPS is obscure because of difficulty in comprehension of three-dimensional cardiac anatomy. Whole-heart magnetic resonance imaging (MRI) is a new, totally non-invasive technique which allows not only depiction of the coronary artery system, but also three-dimensional comprehension of the cardiac structure. We describe a patient with ISPS associated with hypertrophic cardiomyopathy, in whom whole-heart MRI was useful to detect and evaluate the cause of ISPS.