Method of inhibiting restenosis by applying ultrasonic energy

• US 5,836,896 A
• Filed: 08/19/1996
• Issued: 11/17/1998
• Est. Priority Date: 08/19/1996
• Status: Expired due to Term

• Current Assignee: Angiosonics, Inc. (Acolysis Intravascular Ultrasound Business) (Teleflex Incorporated)
• Original Assignee: Angiosonics, Inc. (Acolysis Intravascular Ultrasound Business) (Teleflex Incorporated)
• Inventors: Rosenschein, Uri
• Primary Examiner(s): JAWORSKI, FRANCIS J
• Application Number:
  US08/700,064
• Time in Patent Office: 820 Days
• Field of Search: 601/2-4, 607/97, 606/159, 606/1, 604/22, 128/898
• US Class Current: 601/2
• CPC Class Codes: A61B 17/22012 in direct contact with, or very close to, the obstruction or concrement for removing obstructions in blood vessels by laser A61B18/245
• CPC Class Codes: A61B 2017/22002 preventing restenosis

Abstract

A method and system for inhibiting restenosis by compromising the migration, viability and adhesion of mammalian smooth muscle cells (SMC) is disclosed. The method comprises irradiating the SMC with ultrasonic energy, in an amount which has been found to be effective in inhibiting the migration and adherence of SMC. This method is especially useful in the prevention of restenosis in a blood vessel of a mammal associated with the migration of SMC in the blood vessel following vascular intervention, such as angioplasty. The system disclosed for the prevention of restenosis in a blood vessel of a mammal associated with the migration of SMC in the blood vessel following vascular intervention includes an ultrasonic energy source; a transmitter for transmitting the ultrasonic energy to the blood vessel; and a control unit.

Claims

1. A method of inhibiting restenosis in mammals, comprising:

treating a stenosis of a blood vessel of a mammal, said treatment causing injury to the vessel wall in the region of the stenosis;

applying ultrasound within the vessel to cause cavitation within the vessel in the region of the injury and irradiating smooth muscle cells in the region of the injury with sufficient ultrasound energy to reduce the migration capacity of the smooth muscle cells at least about 2.4 fold without the use of restenosis inhibiting drugs.

2. The method of inhibiting restenosis in mammals of claim 1, wherein said ultrasonic energy supplied is above at least 22.5 watt·

sec and the cavitation threshold of blood.

3. The method of inhibiting restenosis in mammals of claim 1, wherein said ultrasonic energy has a frequency in the range of about 1 kHz. to about 3 MHz.

4. The method of inhibiting restenosis in mammals of claim 1, wherein said ultrasonic energy has a frequency in the range of about 15 kHz. to about 250 kHz.

5. The method of inhibiting restenosis in mammals of claim 1, wherein said irradiating mammalian smooth muscle cells with a restenosis-inhibiting amount of ultrasonic energy occurs after a cardiovascular therapy.

6. The method inhibiting restenosis in mammals of claim 5, wherein said cardiovascular therapy is balloon angioplasty.

15. The method of claim 1, wherein ultrasound is applied with an ultrasonic energy source for providing ultrasonic energy;

a transmitter for transmitting said ultrasonic energy to a blood vessel; and

a control unit controlling said ultrasonic energy source, said ultrasonic energy source, said transmitter and said control unit being constructed and arranged to transmit said ultrasonic energy to said blood vessel in a restenosis inhibiting amount to compromise the migration of smooth muscle cells contained in said blood vessel.

16. The method of claim 1, wherein the treatment includes the implantation of a stent.

7. A therapeutic method for the prevention of restenosis associated with smooth muscle cell migration and adherence in a blood vessel of a mammal following vascular intervention, comprising:

exposing smooth muscle cells in a blood vessel to sufficient ultrasonic energy to reduce the migration capacity of the smooth muscle cells without the use of restenosis inhibiting drugs, at least about 2.4 fold.

8. The therapeutic method for the prevention of restenosis associated with smooth muscle cell migration and adherence in a blood vessel of a mammal following vascular intervention of claim 7, wherein said blood vessel is exposed to said ultrasonic energy by insertion of an ultrasound probe into said blood vessel which causes cavitation within the vessel.

9. The method of claim 8, wherein said ultrasonic energy supplied is above about 22.5 watt·

sec and the cavitation threshold of blood.

10. The method of claim 8, wherein said ultrasonic energy has a frequency in the range of about 1 kHz to about 3 MHz.

11. The method of claim 8, wherein said vascular intervention is balloon angioplasty.

12. The therapeutic method for the prevention of restenosis associated with smooth muscle cell migration and adherence in a blood vessel of a mammal following vascular intervention of claim 7, wherein said blood vessel is exposed to said ultrasonic energy in a non-invasive manner.

13. The therapeutic method for the prevention of restenosis associated with smooth muscle cell migration and adherence in a blood vessel of a mammal following vascular intervention of claim 7, wherein said exposing smooth muscle cells in a blood vessel to ultrasonic energy occurs after a cardiovascular therapy.

14. The therapeutic method for the prevention of restenosis associated with smooth muscle cell migration and adherence in a blood vessel of a mammal following vascular intervention of claim 13, wherein said cardiovascular therapy is one of balloon angioplasty, endarterectomy laser drills, stents, thermal fusion, mechanical drills, and arthrectomy.