Systems and methods for predictable commissural alignment of a replacement heart valve

A transcatheter delivery system comprising:

• a catheter assembly comprising:
• a balloon shaft;
• a balloon mounted onto the balloon shaft, the balloon having a delivery diameter, the balloon in fluid communication with a fluid source for expansion of the balloon from the delivery diameter to a deployed diameter;
• and
• a handle with an actuator, the actuator rotatably engaged with the balloon shaft;
• and
• a valve prosthesis loaded onto the balloon in a loaded configuration, the valve prosthesis expandable from the loaded configuration to a deployed configuration by expansion of the balloon from the delivery diameter to the deployed diameter,
• wherein rotation of the actuator by an actuator rotation amount in at least a first direction predictably rotates the valve prosthesis in the first direction by a valve rotation amount that is proportional to the actuator rotation amount.