Shock wave electrodes

Inventors

Nguyen, Hoa D. • Adams, John M.

Assignees

Shockwave Medical Inc

Abstract

Disclosed herein shock wave catheters comprising one or more shock wave electrodes for cracking calcifications located within blood vessels. In some variations, a shock wave catheter has first and second shock wave electrodes each circumferentially disposed over the outer surface of the catheter. In certain variations, the first electrode has a recess and the second electrode has a protrusion that is received by the recess and a spark gap is located along the separation between the recess and the protrusion. The second electrode can also have a recess that receives a protrusion from a third shock wave electrode, where the separation between the second and third electrodes along the separation between the recess and the protrusion forms a second spark gap. A shock wave can be initiated across these spark gaps when a voltage is applied over the electrodes.

Core Innovation

A treatment catheter includes an axially extending elongate member with circumferentially disposed shock wave electrodes arranged as axially spaced conductive bands. Longitudinal spacing between a first cylindrical conductive band and a second cylindrical conductive band defines at least one spark gap between the conductive bands, and a voltage pulse applied across wires causes current to flow across the spark gap and generate a shock wave in a liquid within a tube surrounding the conductive bands.

In embodiments with multiple conductive bands, longitudinal spacing defines multiple spark gaps between adjacent cylindrical bands, and a voltage pulse applied across selected wires causes current to flow across the spark gaps and generates shock waves in the liquid originating from multiple spark gap locations. The electrode and spark-gap architecture is extended by adding additional distal cylindrical conductive bands and corresponding wires so that additional shock-wave generation occurs at additional spark gaps.

The conductive band arrangement is configured to control spark-gap geometry and shock-wave generation, including aligning distal and proximal ends on the same cylindrical layer and forming one or more cylindrical conductive bands from a hypotube. The document also describes single-layer coplanar electrode pair architectures and associated spark-gap formation using recess and projection features, including complementary recess and projection and optionally interlocking recess and projection.

Claims Coverage

The independent claims cover shock-wave treatment catheter architectures that use conductive electrodes arranged to define at least one spark gap between circumferentially disposed electrode structures, with voltage pulses driving current across the spark gap(s) to generate shock waves in a surrounding conductive liquid and, in one case, fluid in a balloon for impingement on calcified lesions. The claim set also supports multi-spark-gap configurations and electrode-band constructions that structurally constrain spacing and spark-gap locations.

Across the independent claims, the core coverage is directed to treatment catheters that employ circumferentially arranged, axially spaced electrode structures that define spark gaps, with voltage pulses driving current across the spark gap(s) to generate shock waves in an associated fluid to address calcified vascular lesions. The claims further support multi-spark-gap arrangements through additional cylindrical conductive bands and define relationships between numbers of bands and spark gaps, while including structural constraints such as positioning of band ends on cylindrical layers and specific electrode-pair circumferential disposal with navigation facilitation.

Stated Advantages

Documented Applications