2.9. Data collection, monitoring, and quality evaluation

Inclusion and exclusion criteria will be enforced strictly to minimize the potential for the inclusion of confounders. An experienced cardiovascular interventionist (CTO-PCI >50 cases/yr) has been designated to ensure that the success rate of CTO-PCI is above 80%. The number PCI performed within each of the centers participating in this study is least 3,000 cases. An expert committee has been established to ensure interventional safety and prevent study-associated complications. At least two senior experts in PCI (PCI >3000 cases per year) will assist to discern MACEs throughout the follow-up period. Two experienced specialists will acquire CMR images and collect data using specific equipment and software. Two independent investigators will be responsible for the creation of protocols and supervising follow up, and they will communicate with the enrolled participants throughout follow-up. The case report form will be completed by independent investigators. All data obtained will be documented in the database by two independent investigators according to guidelines governing data management. A special inspector will be responsible for tracking, monitoring and reviewing the research process, and it will not be possible to alter data at will. The database will be inactive after cross validation, followed by statistical analysis. The staff that perform analysis will be blinded to the intervention.