Diagnosis and Treatment Guided by 3D Imaging and Modeling: A W-shaped Interventricular Septal Phenotype in Hypertrophic Obstructive Cardiomyopathy.

Surgical treatment of hypertrophic obstructive cardiomyopathy is challenging. It requires balancing adequate myocardial excision against the risk of excessive resection, which can result in an iatrogenic ventricular septal defect. To our knowledge, this is the first reported case of a high-risk septal myectomy in complex anatomy W-shaped hypertrophic obstructive cardiomyopathy with a deep interventricular septum crypt and apical aneurysm. CT angiography-based three-dimensional modeling of the interventricular septum and a virtual myectomy enabled detailed preoperative planning and successful surgery. This planning also informed the choice of a combined transaortic and transapical surgical approach tailored to the patient's anatomy. Keywords: CT Angiography, MR Imaging, Cardiac, Heart, Left Ventricle, Anatomy, Cardiomyopathies, Computer Applications-3D, Computer Applications-Virtual, Segmentation, Modeling, Myocardium, 3D Computer Model, 3D Printing, Cardiac CT Angiography, Cardiac CTA, Cardiac MRI, HOCM, Hypertrophic Obstructive Cardiomyopathy, Septal Myectomy © RSNA, 2026.