Conclusions
CTO intervention remains a technically challenging process, but recent advances in technology and technique have increased procedural success rates and safety. Despite the complexity of the hybrid CTO techniques, these are readily teachable to experienced PCI operators with an interest in CTO. However, given the learning curve for these technically challenging techniques, it is clear that CTO PCI should be concentrated on a relatively few specialist operators. In patients with significant angina, CTO intervention is proven to be highly effective at relief of symptoms. This is likely to be cost effective – even allowing for increases in procedural costs associated with newer hybrid strategies. In patients with demonstrable ischaemia in a territory supplied by an occluded vessel, CTO intervention is likely to offer prognostic benefit but this has not yet been confirmed in a large scale randomised trial.