Vascular access complications can occur during or after cardiac or peripheral arterial catheterization. These complications increase patient morbidity and mortality, as well as healthcare costs. Several strategies and devices have been employed to decrease the risk for vascular access complications, such as fluoroscopy-guided access, ultrasound-guided access and vascular closure devices. Randomized trial data has failed to demonstrate that fluoroscopic guidance reduces common femoral artery access complications. While meta-analysis data has demonstrated that vascular closure devices decrease time to arterial hemostasis, increase patient mobilization and facilitate earlier patient discharge, they do not reduce the incidence of vascular complications as compared to hemostasis achieved with manual pressure. Ultrasound guidance has been shown to facilitate femoral artery access and reduce femoral artery vascular complications. A new device, the Micropuncture Kit (Cook Medical, Bloomington, IN) allows vascular access with a small 21gauge needle as opposed to the standard method, which requires an 18 gauge needle. The use of the Micropuncture Kit for the purpose of decreasing vascular access complications has not been examined in a randomized study to date.