Development of a 3-D printing-based cardiac surgical simulation curriculum to teach septal myectomy

We sought to develop a 3-D printing-based simulator for teaching extended septal myectomy to trainees in cardiothoracic surgery (clinical postgraduate year 4-7). This procedure is difficult to teach because of generally unfamiliar and highly variable anatomy, limited visibility for the assistant, and significant potential complications.

A curriculum using multimedia didactics and 3-D print-based patient-specific surgical simulation was implemented. Six identical 3-D prints were constructed for each of 5 consecutive patients. Preoperative septal myectomy was performed on each printed heart by an attending surgeon and 5 residents. Model myectomy specimen volumes were measured according to liquid displacement. All print resections were videotaped and blindly evaluated by 3 attending surgeons. Pre- and post-test evaluations, and a survey tool were also used to evaluate the curriculum.

Baseline myectomy resection volumes differed significantly (attending 15 cm³ vs resident 3.1 cm³; P < .05). Residents resected increasingly larger volumes of tissue over the course of the study. Initial resection volume (compared with faculty) increased by 0.82 cm³ per resection (95% confidence interval, 0.37-1.3 cm³; P < .0001). Total resection volume (compared with faculty) increased by 3.6 cm³ per resection (95% confidence interval, 2.4-4.9 cm³; P < .0001). The residents' survey assessment of the simulator was favorable.

A patient-specific 3-D printing-based simulation module shows promise as a tool to augment and improve cardiothoracic resident training in septal myectomy. The residents were quickly able to perform resections on par with the attending. Residents rated the simulator favorably. Each resident benefited by experiencing the variable anatomy of 5 separate patient-specific models.