A delivery apparatus including a measurement device to monitor the real-time diameter of a prosthetic heart valve can include a handle, at least one first actuator extending from the handle and being configured to apply a distally directed force to a proximal end portion of a prosthetic heart valve, at least one second actuator extending from the handle and being configured to apply a proximally directed force to a distal end portion of a prosthetic heart valve, a sensor, and first and second motion-transmitting members coupled to the first and second actuators, respectively, and having proximal ends coupled to the sensor, wherein the sensor senses relative movement between the motion-transmitting members upon actuation of the first and second actuators to determine the diameter of the prosthetic heart valve as it expands from a radially compressed configuration to a radially expanded configuration.