Scoring system related to retrograde percutaneous coronary intervention for coronary chronic total occlusion

The retrograde approach is a principal procedure used in coronary chronic total occlusion percutaneous coronary intervention. However, the retrograde approach presents more challenges compared with the antegrade approach, as it is associated with a lower rate of success and a higher risk of complications. An accurate pre-procedural evaluation of the complexity of a lesion could aid in the planning of the procedure, in estimating the procedure's duration, or in determining whether the patient should be referred to another center specializing in CTO-PCI, as well as in a more precise evaluation of the risk-benefit ratio. In recent years, multiple scoring systems have been created to forecast the success and efficiency of the retrograde procedure. However, each scoring system was developed independently, and comparative studies were lacking. This article provides a review of these scoring systems, offers an overview of the current state of the retrograde approach, and aims to stimulate further discussion on this topic.