Contrast Enhanced Magnetic Resonance Angiography (MRA) is a developing technology for the non-invasive evaluation of arterial and venous structures which does not require x-ray based catheter angiography. While dramatic progress in MRA has recently been made, there are still substantial limitations in the accuracy of MRA in grading stenoses and detecting small accessory vessels. The purpose of this study is to recruit patients with documented atherosclerotic disease as confirmed on catheter angiography performed at Suburban Hospital for evaluation with state-of-the-art MRA on MRI units, also at Suburban Hospital. We intend to test new surface coils, new pulse sequence designs, and advanced image processing algorithms in order to improve MRA accuracy to the point that a large-scale study of MRA vs. conventional angiography is possible. The goal of this pilot study is to improve MRA to the point that it can reliably replace diagnostic x-ray catheter angiography in the evaluation of patients with atherosclerotic disease.