Characterization of left atrial assist device implantation: Early results of ex vivo anatomical assessment

BACKGROUND: The left atrial assist device (LAAD) is a novel pump that was developed specifically for the treatment of heart failure with preserved ejection fraction. The device is surgically implanted in the mitral position. This study aimed to characterize the various device-fitting configurations in the mitral annular position. METHODS: Rapidly prototyped LAAD models (n = 5) were fabricated with five different driveline configurations: (A) annulus level/intra-cuff running; (B) supra-cuff/below coronary sinus (CS); (C) infra-cuff; (D) supra-annulus/supra-CS; (E) left ventricular free wall level. The 3D-printed models were implanted in extracted fresh porcine hearts (80-100 kg, adult, healthy porcine) and the proximity of anatomical structures between the driveline and CS and coronary artery (CA) were measured. RESULTS: All five device configurations were evaluated for fitting. For the purpose of preventing blood clot formation around the driveline, the mitral annulus (MA) as a driveline pass-way (configuration A) has been considered advantageous with the current device, in that the driveline exposure to blood has been avoided. The CS does not exist at exactly the same level as the MA, and there is less risk of injuring it than using the left atrial free wall. However, there is an inevitable risk of damaging the CA, so careful visual inspection before inserting the driveline is needed. CONCLUSIONS: Several options of driveline exteriorization were demonstrated, and the safety of each configuration was evaluated. Using the MA as a pathway for the driveline exit is considered to be a reasonable and safe method.