APPARATUS, SYSTEMS, AND METHODS FOR ACHIEVING INTRAVASCULAR, THERMALLY-INDUCED RENAL NEUROMODULATION
Apparatus, systems, and methods for achieving thermally-induced renal neuromodulation by intravascular access are disclosed herein. One aspect of the present application, for example, is directed to apparatuses, systems, and methods that incorporate a treatment device comprising an elongated shaft. The elongated shaft is sized and configured to deliver a thermal element to a renal artery via an intravascular path. Thermally-induced renal neuromodulation may be achieved via direct and/or via indirect application of thermal energy to heat or cool neural fibers that contribute to renal function, or of vascular structures that feed or perfuse the neural fibers.
1 . A catheter apparatus, comprising:
an elongated shaft extending along an axis, the elongated shaft comprising a proximal end region and a distal end region, the distal region including a first flexure zone and a second flexure zone adjacent to and extending distally beyond the first flexure zone;
a handle coupled to the proximal end region;
a thermal element carried by and extending distally beyond the second flexure zone;
a flexure control element coupled to the first flexure zone and configured to apply a first force to the first flexure zone to move the first flexure zone of the distal region of the elongated shaft in a radial direction away from the axis;
a flexible structure within the second flexure zone that is coupled to the thermal element and configured to allow passive flexure about the axis in response to a second force applied to the thermal element via contact with a tissue surface;
a flexure controller carried by the handle and coupled to the flexure control element, wherein the flexure controller is configured to cause the flexure control element to apply the first force to move the first flexure zone; and
a connector carried by the handle and configured to connect the thermal element to a thermal energy source;
wherein the thermal element is configured to apply treatment to a tissue region adjacent to the tissue surface.
2 . The catheter apparatus of claim 1 wherein the first flexure zone is configured to move in a predetermined radial direction in response to the first force applied by the flexure control element.
3 . The catheter apparatus of claim 1 wherein the flexure control element comprises a wire coupled to a distal portion of the first flexure zone, and wherein the first force applied to the first flexure zone is a bending or compressive force resulting from actuation of the flexure controller.
4 . The catheter apparatus of claim 1 , further comprising a sensor adjacent to, on, or within the thermal element, and wherein the sensor is configured to monitor a parameter of at least one of the apparatus and the tissue surface.
5 . The catheter apparatus of claim 4 wherein the sensor is at least one of a temperature sensor, impedance sensor, optical sensor, or micro sensor.
6 . The catheter apparatus of claim 4 , further comprising a feedback control system configured to alter treatment delivered to the tissue surface in response to the monitored parameter.
7 . The catheter apparatus of claim 6 wherein the feedback control system comprises an algorithm for controlling output of the thermal energy source.
8 . The catheter apparatus of claim 1 wherein the flexure control element and the flexible structure are configured to mutually create, via the first flexure zone and the second flexure zone, a stabilizing force between the thermal element and the tissue surface.
9 . The catheter apparatus of claim 8 wherein the stabilizing force causes at least twenty-five percent of the total surface area of the thermal element to contact the tissue surface.
10 . The catheter apparatus of claim 1 wherein the thermal element is configured to apply treatment to the tissue region using at least one of radiofrequency energy, microwave energy, ultrasound energy, laser/light energy, thermal fluid, and cryogenic fluid.
11 . The catheter apparatus of claim 1 wherein the thermal element comprises an electrode for applying radiofrequency energy to tissue.
12 . The catheter apparatus of claim 1 , further comprising a radiopaque marker configured to facilitate angiographic visualization of the catheter apparatus.
13 . The catheter apparatus of claim 1 wherein the handle comprises a rotating fitting coupled to the elongated shaft and configured to rotate the elongated shaft about the axis without rotating the handle, and wherein the rotating fitting comprises a rotational limiting element configured to prevent rotation of the elongated shaft beyond a predetermined number of revolutions.
14 . The catheter apparatus of claim 1 wherein the catheter apparatus is a component of a medical treatment kit, and wherein the medical treatment kit further comprises a cable configured to electrically connect the catheter apparatus to the thermal energy source and a dispersive electrode configured to provide a return path for an energy field from the catheter apparatus.
15 . The catheter apparatus of claim 1 , further comprising instructions for delivering the catheter apparatus into a renal artery of the patient and at least partially denervating a kidney of the patient corresponding to the renal artery to treat the patient for a condition associated with at least one of hypertension, heart failure, kidney disease, chronic renal failure, sympathetic hyperactivity, diabetes, metabolic disorder, arrhythmia, acute myocardial infarction and cardio-renal syndrome.
16 . A catheter apparatus, comprising: a thermal element;
an elongated shaft extending along an axis; and
a distal flexure zone separating the thermal element and the elongated shaft, wherein the distal flexure zone is configured to carry the thermal element and facilitate stable contact between the thermal element and a tissue surface, and further wherein the distal flexure zone comprises a flexible structure that accommodates passive flexure in any plane through the axis during contact between the thermal element and the tissue surface.
17 . The catheter apparatus of claim 16 wherein the flexible structure is configured for up to ninety degrees of flexure from the axis.
18 . The catheter apparatus of claim 16 wherein the distal flexure zone electrically isolates the thermal element from the elongated shaft.
19 . The catheter apparatus of claim 16 wherein the distal flexure zone is configured to facilitate stable contact between a side of the thermal element and the tissue surface.
20 . The catheter apparatus of claim 16 wherein the flexible structure comprises a polymer.
21 - 48 . (canceled)