Patients with a Fontan circulation have a diminished life expectancy of only 30-40 years old. A mechanical circulatory assist device can potentially increase their life expectancy and quality of life. Given the complexity of the anatomy and physiology of the Fontan circulation, design of a safe and effective mechanical assist device is a challenging task. A device based on a viscous impeller pump is very attractive. Such a device is amenable for minimally invasive implantation through a catheter, given the miniaturization of its actuator is possible. The current thesis provides the first steps in designing and developing the small brushless electromagnetic motor intended to drive the viscous impeller pump. First, a list of requirements was defined for such an actuator. The essential requirements are that the actuator is 5.4 mm in diameter and 11 mm in length, has an outrunner configuration, can reach a power output of at least 0.92 Watts and that the within the motor generated temperature does not excessively heat up the surrounding blood or breaks the actuator. After that, the actuator's first concept was defined and validated on the torque output and heat generation. After that, various optimizations of the design were performed, which resulted in a potentially promising actuator concept. Although, the presented actuator concept meets the prescribed dimensions and is an outrunner BDLC motor, the predicted power and torque output of 0.632 Watts and 2446 μNm, respectively, both are above the required values. The actuator needs to be tested to conclude if the actuator can indeed provide sufficient drive resulting in required pumping power of the VIP.