Intima Versus Adventitia Drug Delivery to Elucidate Mechanisms of Restenosis: Magnetic Resonance Imaging

Peripheral artery disease (PAD) affects at least 12 million Americans annually with more than half a million patients undergoing an endovascular or surgical revascularization procedure in order to treat the disease. Unfortunately, about two-thirds of patients still have blockages in the leg arteries, even after these procedures. Advances in Magnetic resonance imaging (MRI) offer promise for understanding the mechanism of failure through insights into vessel wall composition, remodeling, and inflammation. Restenosis has a known relationship to inflammation. Advances in micro-catheter technologies offer the ability to deliver anti-inflammatory medications such as Dexamethasone (DEX) directly to the adventitia and advances in drug delivery on balloon surfaces to deliver paclitaxel to the intima of the artery. This study aims to investigate if patient-specific parameters affect angioplasty outcomes, if DEX has a biological effect on the vessel wall, and if this effect is through the reduction of inflammation. In response to an FDA issued "Letter to Healthcare Providers" dated August 9, 2019 that reported the "relative risk for increased mortality at 5 years was 1.57 (95% confidence interval 1.16 - 2.13), which corresponds to a 57% relative increase in mortality in patients treated with paclitaxel-coated devices," participant enrollment in the paclitaxel drug coated balloon arm was stopped and a plain balloon angioplasty arm was added to the protocol.