The National Cardiovascular Data Registry (NCDR®) CathPCI Registry (v. 4.3, 4.4) was selected as the data entry format for both pilot hospitals and non-pilot hospitals. The pilot PCI data is entered using the NCDR® CathPCI Registry v.4.3 and v.4.4 on an internet accessible UCD Velos server (Velos eResearch v9.1.2, Velos, Inc., Fremont, CA). The non-pilot hospitals enter their data using various NCDR® approved onsite software or the central NCDR® CathPCI v.4.3 and v.4.4 website. The pilot hospital data is entered within 72 hours of each procedure and immediately available to the PCI-CAMPOS coordinating center. The non-pilot data is entered individually or obtained from quarterly data harvests submitted to NCDR®. After masking patient, operator, and hospital identity, this non-pilot California NCDR® CathPCI registry data is downloaded annually from the NCDR® center to the UCD PCI-CAMPOS coordinating center. The UCD coordinating center performs all pilot audits and has full access to the pilot information. The UCD coordinating center performs all pilot and comparative analyses. Interim data summaries and analyses are presented to the full AOC for review at 6-12 month intervals throughout the study.