US Patent 10376170 Catheter with annular lumen to provide distal flushing

A mapping catheter including an elongate catheter body extending from a proximal end to a distal end, a handle connected to the proximal end of the catheter body, an electrode array connected to the distal end, a deployment shaft, and an irrigation system. The catheter body includes at least one lumen. The irrigation system includes a manifold and a thin, polymeric irrigation tube. The manifold is disposed within the handle and is connectable to a source of irrigation fluid. The irrigation tube is connected to the manifold and extends around the deployment shaft from the manifold to the distal end of the catheter through the catheter body lumen. The irrigation tube forms an annular lumen between an inner surface of the irrigation tube and an outer surface of the deployment shaft. The annular lumen is configured to carry irrigation fluid from the manifold to the array.