P22: The Cleveland Clinic Universal Ventricular Assist Device: Preliminary Ex Vivo Evaluation of an Interchangeable Inflow Cannula

Abstract

Objective: To enable customized cannulation strategies based upon anatomical or clinical scenarios, the interchangeable (IC) inflow cannula has been designed. This study aimed to assess the compatibility of the IC cannula with the Cleveland Clinic Universal Ventricular Assist Device (UVAD) in the porcine ex vivo assessment. Methods: Porcine heart specimens (n = 12) were divided into two groups. Specimens were randomly assigned for cannulation of the left ventricle (LV) (n = 6) and right ventricle (RV) (n = 6) (Figure 1). The IC cannulas were prototyped at lengths of 20, 30, and 70 mm. In an ex vivo setup, UVAD was operated at various pump speeds. Pressure and pump data, including the number of suction events, were recorded. Results: The ex vivo study demonstrated various characteristics of the cannula in an isolated porcine heart. The mean pump flow in the LV for 20, 30, and 70 mm cannula was 2.3 ± 0.8, 2.3 ± 0.9, and 2.4 ± 0.9 L/min, respectively. Wall suction with LV cannulation was observed more frequently in the 70 mm cannula (49.1%) compared to the 20 mm cannula (29.8%) and 30 mm cannula (21.1%) (p = 0.01). In the RV setting, a 70 mm cannula showed a greater mean pump flow of 1.5 ± 0.6 L/min (p < 0.01) compared to the 20 mm cannula (1.0 ± 0.5 L/min) and 30 mm cannula (1.4 ± 0.3 L/min). In addition, suction with RV cannulation was most frequent with a 70 mm cannula (70 mm, 47.8% vs. 30 mm, 10% vs. 20 mm, 10%, p < 0.01). Conclusion: The results support the feasibility and versatility of using IC cannulas customized to various heart geometries and characteristics. The range of inflow cannula lengths allows for real-time assessment during surgery to select the most suitable cannula for optimal pump performance.Figure 1. Scheme of the ex vivo setup.