Selectively deployable catheter ablation devices

Inventors

Curley, Michael G. • Kim, Fredrick J. • Howard, Michael T. • Delly, Erik • Eberl, Gregory R. • Lesica, Jeffrey J.

Assignees

Thermedical Inc

Abstract

Catheters with deployable instruments (e.g., needles) can damage tissue if the instrument unintentionally deploys during use. Described herein are devices and methods for controlling the position of a deployable catheter instrument. In one embodiment, a catheter can include an instrument slidably disposed within an inner lumen of the catheter and coupled to at least one protrusion, as well as a retraction stop coupled to the catheter. The catheter can further include a biasing element coupled to the instrument that can urge the instrument proximally such that the at least one protrusion abuts against the retraction stop, as well as an advancing mechanism to selectively engage the instrument and urge it distally. In some embodiments, the biasing element can be omitted and a deployment stop can be included distal to the retraction stop. These configurations can prevent unintentional instrument deployment and provide greater positioning precision during instrument deployment.

Core Innovation

The disclosure relates to selectively deployable catheter ablation devices that prevent inadvertent exposure of a deployable instrument, such as a needle tip, during catheter steering. A distal datum position is established using a retraction stop on the catheter and a corresponding protrusion, flange, rib, or ledge on the needle or connecting member so that the needle tip position is fixed relative to the catheter distal tip when the needle is biased proximally against the retraction stop.

This fixed position is maintained despite catheter shortening from steering, while still allowing selectable needle deployment controlled by a separate advancing mechanism. The advancing mechanism selectively overcomes the biasing urging, and examples include a clutch that selectively couples to the needle, with deployment control and user feedback via indicator lights when the clutch engages.

Additional deployment stop embodiments provide repeatable selectable deployment distances distal to the steering region, including multiple tracks, keyed flanges and through-holes, tortuous or labyrinth tracks with transitions, angularly indexed tracks, intermediate adjustable shaft stops, and detent-based stops, optionally omitting a biasing element in some stop-based designs.

In ablation embodiments, the needle includes a distal portion configured to ablate tissue and is associated with fluid-enhanced ablation therapy using outlet ports and fluid channels in the needle. Optional heating elements heat fluid in the needle lumen near the outlet ports, and an ablation element associated with the needle, such as a conductive needle surface for RF electrical energy, ablates tissue using energized and/or heated fluid delivered through the outlet ports.

Claims Coverage

The partial content identifies three independent claims: clm-00001, clm-00010, and clm-00012. Each independent claim shares a common base architecture and then differs by specific inventive structure of the advancing mechanism and/or needle protrusion features.

Across the independent claims, the core coverage combines a catheter retraction stop, a needle with an ablation distal portion and outlet ports, a biasing element that positions the needle by abutting a needle protrusion against the retraction stop, and an advancing mechanism that selectively urges the needle distally. Additional claim coverage further includes selective advancing via a clutch and/or defines that the needle protrusion includes one or more fluid channels to allow fluid flow through the protrusion(s).

Stated Advantages

Documented Applications