Method and apparatus for heating inflammed tissue
AssigneesBoard of Regents, The University of Texas System, Texas Heart Institute
InventorsMorteza Naghavi, Bujin Guo, Birendra Lal, S. Ward Casscells, III, James T. Willerson
Life of this patent
Estimating the term…
Abstract
The present invention relates to methods for treating inflammation in body tissues. More specifically, certain disclosed methods relate to selectively inducing apoptosis in inflammatory immune cells by heating cells for a sufficient time and at a sufficient temperature to induce programmed cell death. The disclosed stents can be placed in contact with the inflammatory cells and heated under controlled conditions. The disclosed apparatus and methods are particularly suitable for treating athersclerotic plaques.
Claims29
An ultrasonically heatable stent comprising at least one ultrasound-absorptive material characterized by an acoustic impedance greater than that of living soft tissue.
A method of making an ultrasonically heatable stent comprising:
- obtaining a stent framework configured for maintaining patency of a vessel;
- obtaining a biocompatible coating material characterized by having an acoustic impedance greater than that of human soft tissue;
- applying a coating of said material to said stent framework, said coating being of such thickness and character that said stent is heatable by ultrasound at a faster rate than human soft tissue.
A method of reducing or eliminating a population of inflammatory cells on an implanted synthetic vascular graft in a living subject comprising:
- advantageously positioning an ultrasound transducer external the body of said subject;
- and
- operating said ultrasound transducer such that an ultrasonic beam is directed at said synthetic vascular graft, whereby the temperature of the graft, or a portion thereof, is increased to and maintained at about 1-5° C. above ambient vessel temperature for a sufficient period of time to heat said graft or portion thereof at a temperature of 38-42° C., provided that said synthetic graft contains an ultrasound-absorptive material characterized by an acoustic impedance greater than that of human tissue and that is chemically stable when heated up to about 45° C.
An ultrasonically heatable stent comprising at least one ultrasound-absorptive material characterized by an acoustic impedance greater than that of living soft tissue;
- said stent comprising a stent framework configured to maintain patency of a human vessel;
- and
- a coating comprising said at least one ultrasound-absorptive material overlying said stent framework and characterized by being heatable by ultrasound at a faster rate than living soft tissue.
An ultrasonically heatable stent comprising at least one ultrasound-absorptive material characterized by an acoustic impedance greater than that of living soft tissue;
- said stent comprising:
- a stent framework configured to maintain patency of a human vessel, and
- a coating comprising said at least one ultrasound-absorptive material overlying said stent framework and characterized by being heatable by ultrasound at a faster rate than living soft tissue;
- wherein said coating further comprises a heat-releasable drug.
A method of delivering a drug to a site in vivo, comprising the steps of:
- incorporating the drug into an ultrasonically heatable polymeric coating of a stent;
- delivering the coated stent to a specific region in vivo;
- and
- directing an external ultrasound source toward the stent, thereby heating the coating and releasing the drug.
Dependencies are inferred from the claim text.