Patent Publication Number: US-2023157754-A1

Title: Faster rise time pulse shaping of plasma generated pressure waves for disruption of vascular calcium

Description:
The present invention is directed toward a catheter system for treating a treatment site within or adjacent to a vessel wall or a heart valve. In various embodiments, the catheter system includes an inflatable balloon, an optical fiber, and a laser. The optical fiber has a fiber distal end positioned within the inflatable balloon. The optical fiber is configured to receive an energy pulse so that the optical fiber emits light energy in a direction away from the optical fiber to generate a plasma pulse within the inflatable balloon. The laser includes (i) a seed source that is configured to emit a seed pulse, and (ii) an amplifier that is configured to increase energy of the seed pulse so that the laser generates the energy pulse that is received by the optical fiber, the energy pulse having a waveform with a duration T, a minimum power P 0 , a peak power P P , and a time from P 0  to P P  equal to T P , wherein T P  is not greater than 40% of T, wherein P P  is within the range of greater than 50 kW and less than 1000 kW. 
     In certain embodiments, wherein T P  is not greater than 30% of T. 
     In some embodiments, wherein T P  is not greater than 25% of T. 
     In various embodiments, wherein T P  is not greater than 20% of T. 
     In certain embodiments, wherein T P  is not greater than 10% of T. 
     In some embodiments, wherein T P  is not greater than 5% of T. 
     In various embodiments, wherein T is within the range of greater than 50 ns and less than 3 μs. 
     In certain embodiments, wherein T is within the range of greater than 100 ns and less than 2 μs. 
     In some embodiments, wherein T is within the range of greater than 200 ns and less than 1 μs. 
     In various embodiments, wherein T is within the range of greater than 300 ns and less than 800 ns. 
     The present invention is also directed toward a catheter system for treating a treatment site within or adjacent to a vessel wall or a heart valve. In various embodiments, the catheter system includes an inflatable balloon, an optical fiber, and a laser. The optical fiber has a fiber distal end positioned within the inflatable balloon. The optical fiber is configured to receive an energy pulse so that the optical fiber emits light energy in a direction away from the optical fiber to generate a plasma pulse within the inflatable balloon. The laser includes (i) a seed source that is configured to emit a seed pulse, and (ii) an amplifier that is configured to increase energy of the seed pulse so that the laser generates the energy pulse that is received by the optical fiber, the energy pulse having a waveform with a duration T, a minimum power P 0 , a peak power P P , and a time from P 0  to P P  equal to T P , wherein T P  is not greater than 40% of T, wherein a ratio in kW to ns of P P  to T P  is greater than 1:5. 
    
    
     In certain embodiments, T is within the range of greater than 50 ns and less than 3 μs. 
     In some embodiments, T is within the range of greater than 100 ns and less than 2 μs. 
     In various embodiments, T is within the range of greater than 200 ns and less than 1 μs. 
     In certain embodiments, T is within the range of greater than 300 ns and less than 800 ns. 
     In some embodiments, T is within the range of greater than 400 ns and less than 600 ns. 
     In various embodiments, T P  is within the range of greater than 2.5 ns and less than 1 μs. 
     In certain embodiments, T P  is within the range of greater than 5 ns and less than 800 ns. 
     The present invention is further directed toward a catheter system for treating a treatment site within or adjacent to a vessel wall or a heart valve. In various embodiments, the catheter system includes an inflatable balloon, an optical fiber, and a laser. The optical fiber has a fiber distal end positioned within the inflatable balloon. The optical fiber is configured to receive an energy pulse so that the optical fiber emits light energy in a direction away from the optical fiber to generate a plasma pulse within the inflatable balloon. The laser includes (i) a seed source that is configured to emit a seed pulse, and (ii) an amplifier that is configured to increase energy of the seed pulse so that the laser generates the energy pulse that is received by the optical fiber, the energy pulse having a waveform that approximates a square wave, the waveform having a duration T, a minimum power P 0 , a peak power P P , and a time from P 0  to P P  equal to T P , wherein T P  is greater than 40% of T. 
     The present invention is still further directed toward a catheter system for treating a treatment site within or adjacent to a vessel wall or a heart valve. In various embodiments, the catheter system includes an inflatable balloon, an optical fiber, and a laser. The optical fiber has a fiber distal end positioned within the inflatable balloon. The optical fiber is configured to receive an energy pulse so that the optical fiber emits light energy in a direction away from the optical fiber to generate a plasma pulse within the inflatable balloon. The laser includes (i) a seed source that is configured to emit a seed pulse, and (ii) an amplifier that is configured to increase energy of the seed pulse so that the laser generates the energy pulse that is received by the optical fiber, the energy pulse having a waveform that approximates a triangular wave, the waveform having a duration T, a minimum power P 0 , a peak power P P , and a time from P 0  to P P  equal to T P , wherein T P  is greater than 40% of T, wherein T P  is greater than 60% of T. 
     This summary is an overview of some of the teachings of the present Application and is not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details are found in the detailed description and appended claims. Other aspects will be apparent to persons skilled in the art upon reading and understanding the following detailed description and viewing the drawings that form a part thereof, each of which is not to be taken in a limiting sense. The scope herein is defined by the appended claims and their legal equivalents.