Date of Award
Master of Science (MS)
Lee , JeoungSoo
Langan , Eugene
Cardiovascular disease is the leading cause of death in the United States. Atherosclerosis is the main contributing factor for CVD. Current treatment methods for atherosclerosis include balloon angioplasty and stent implantation, which both have drawbacks associated with them. Balloon angioplasty shows restenosis in 3-6 months after deployment in 25-50% of patients. Bare metal stents have all the risks associated with implanting a medical device in a blood contacting area along with restenosis due to neointimal hyperplasia and stent fracture. In coronary arteries, drug-eluting stents (DES) have been shown to be very safe and effective with a very low percentage of major adverse cardiac events when implanted properly, but they require double antiplatelet therapy for a minimum of 1 year and have proven less effective in peripheral arteries. In peripheral arteries stents have not been as effective because of the increased stresses put on the arteries by muscle contractions and movement. Most notably the superficial femoral artery (SFA) travels through the hunter's or adductor canal in the quadriceps. The stress from quadriceps contractions can lead to stent fracture and ultimately dissection of the artery. To try and solve this problem drug coated balloons have tried to combine the positive qualities of DES for localized anti-proliferative drug delivery with angioplasty balloons that do not leave foreign materials in the body. Estrogen is one such anti-proliferative drug that has been shown to inhibit smooth muscle cell proliferation in vitro and in vivo. To study the safety and efficacy of an estrogen-coated balloon in vitro static studies were performed. These studies used static weight simulations to approximate an estrogen-coated balloon expansion. Cells were then analyzed to examine the simulation's effect on cell proliferation, apoptosis, hypertrophy, and phenotype. The studies statistically supported that estrogen treated balloon angioplasty simulation had lower cell proliferation than uncoated balloon angioplasty simulation and the control. The estrogen treated balloon angioplasty simulation also showed no statistical significant differences in the amount of apoptosis, hypertrophy, or phenotypic change when compared to uncoated balloon angioplasty simulation. A dynamic vascular flow model was designed to replicate an interventional cardiologist's path from balloon insertion to deployment in the SFA. This model will be used to analyze coating techniques and drug lost from the balloon surface while the balloon is in transit to the site of deployment. The flow model has the ability to be modified to simulate varying amounts of vessel stenosis.
Metzger, Adam, "Static and Dynamic in vitro Testing of Estrogen Coated Balloons" (2014). All Theses. 1849.