Abstract
Current methods for delivery of an anti-restenosis drug to an arterial vessel wall post-percutaneous transluminal
angioplasty and stent placement are limited in terms of drug choice, dosing level, and ability to assure drug coverage
between the struts of a drug eluting stent. Intravascular ultrasound (IVUS) provides real-time, radiation-free, imaging
and assessment of atherosclerotic disease in terms of anatomical, functional and molecular information. In this
presentation, the design of a dual imaging / therapy IVUS catheter is described and results documenting gene and
drug delivery reported. Microbubbles and drug / gene (shell associated or co-injected) are dispensed from the catheter
tip. Using this approach, it becomes possible to address the need for complete vessel wall coverage and achieve
delivery in regions poorly addressed using conventional stent-based approaches. A range of in vitro, ex vivo and in
vivo results are presented. Our most recent results involve a demonstration in a pig model of coronary balloon angioplasty
that produced a 33% reduction in neointima formation versus a drug plus microbubble, but no ultrasound,
control.
