Acoustic transducer for pulse-echo monitoring and control of thermally ablative lesioning in layered and nonlayered tissues, catheter contact monitoring, tissue thickness measurement and pre-pop warning

摘要

An ablation catheter with acoustic monitoring comprises an elongated catheter body; a distal member disposed adjacent a distal end and including an ablation element to ablate a biological member at a target region outside the catheter body; and one or more acoustic transducers each configured to direct an acoustic beam toward a respective target ablation region and receive reflection echoes therefrom. The distal member includes a transducer housing in which the acoustic transducers are disposed, the transducer housing including at least one transducer window which is the only portion in the distal member through which the acoustic beam passes, at least the at least one transducer window portion of the distal member being made of a material comprising at least 50% carbon by volume, the transducer window material having an acoustic impedance between that of the acoustic transducers and that of the biological member.