A catheter assembly includes an imaging core insertable into a lumen of a sheath of a catheter. The imaging core includes a rotatable driveshaft and a transducer that is coupled to the driveshaft and that rotates with the driveshaft. One or more inlet ports and one or more outlet ports are defined in a distal portion of the sheath. A flow-inducing element is coupled to the driveshaft and rotates with the driveshaft. The flow-inducing element draws fluid into the lumen through the inlet port(s) from the environment external to the sheath and pushes the drawn fluid out of the lumen through the outlet port(s). One of the one or more inlet ports or the one or more outlet ports is disposed proximal to the flow-inducing element and the transducer, and the other of the inlet port(s) or the outlet port(s) is disposed distal to the flow-inducing element and the transducer.
