A catheter, comprising: at least a first transducer; at least a first balloon, the first transducer located in an interior of the first balloon, the first transducer configured to be operated at an operational frequency, wherein: the first transducer transmits an acoustic signal that provides a first acoustic field with multiple lobes along a longitudinal axis of the first transducer, each of the lobes has a spatial intensity maximum in a spatial intensity distribution of the first acoustic field, the spatial intensity distribution being at a surface of the first balloon and parallel to a surface of the first transducer, the spatial intensity distribution of the first acoustic field having one or more reduced spatial acoustic intensity locations where the spatial intensity of the acoustic field of the first transducer is 50% or less of a value of one of the spatial intensity maxima of the first transducer, each of the reduced spatial acoustic intensity locations being between the spatial intensity maxima for lobes that are adjacent to one another along the longitudinal axis of the first transducer, and each of the reduced spatial acoustic intensity locations being on the surface of the first balloon between the spatial intensity maxima that are adjacent to one another along the longitudinal axis of the first transducer, characterized by: at least a first electrode configured to transmit an electromagnetic signal, the first electrode being positioned on the first balloon at one of the reduced spatial acoustic intensity locations of the first transducer. at least a first transducer; at least a first balloon, the first transducer located in an interior of the first balloon, the first transducer configured to be operated at an operational frequency, wherein: the first transducer transmits an acoustic signal that provides a first acoustic field with multiple lobes along a longitudinal axis of the first transducer, each of the lobes has a spatial intensity maximum in a spatial intensity distribution of the first acoustic field, the spatial intensity distribution being at a surface of the first balloon and parallel to a surface of the first transducer, the spatial intensity distribution of the first acoustic field having one or more reduced spatial acoustic intensity locations where the spatial intensity of the acoustic field of the first transducer is 50% or less of a value of one of the spatial intensity maxima of the first transducer, each of the reduced spatial acoustic intensity locations being between the spatial intensity maxima for lobes that are adjacent to one another along the longitudinal axis of the first transducer, and each of the reduced spatial acoustic intensity locations being on the surface of the first balloon between the spatial intensity maxima that are adjacent to one another along the longitudinal axis of the first transducer, characterized by: the first transducer transmits an acoustic signal that provides a first acoustic field with multiple lobes along a longitudinal axis of the first transducer, each of the lobes has a spatial intensity maximum in a spatial intensity distribution of the first acoustic field, the spatial intensity distribution being at a surface of the first balloon and parallel to a surface of the first transducer, the spatial intensity distribution of the first acoustic field having one or more reduced spatial acoustic intensity locations where the spatial intensity of the acoustic field of the first transducer is 50% or less of a value of one of the spatial intensity maxima of the first transducer, each of the reduced spatial acoustic intensity locations being between the spatial intensity maxima for lobes that are adjacent to one another along the longitudinal axis of the first transducer, and each of the reduced spatial acoustic intensity locations being on the surface of the first balloon between the spatial intensity maxima that are adjacent to one another along the longitudinal axis of the first transducer, characterized by: at least a first electrode configured to transmit an electromagnetic signal, the first electrode being positioned on the first balloon at one of the reduced spatial acoustic intensity locations of the first transducer.