Systems and methods for treating vascular occlusions with catheter based ultrasound

Abstract

A system and method is provided for generating ultrasound at the tip of an intravascular catheter. This may be used for the treatment of vascular occlusions, including chronic total occlusions (CTOs) and thrombotic occlusions (e.g., deep vein thrombosis, stroke, myocardial infarction). For instance, the systems and methods may be used to induce cavitation to enhance the enzymatic degradation of a vascular occlusion. In some configurations, the approach employs a hollow cylindrical transducer, electrically stimulated in the radial direction at a frequency corresponding to the length mode excitation, thereby projecting ultrasound forwards past the catheter tip. This design overcomes electrical impedance issues for the generation of low frequencies with a smaller diameter transducer capable of negotiating a coronary artery. The hole within the transducer may accommodate a guidewire to facilitate its placement adjacent to the proximal portion of the occlusion.