PROGRESS-CTO Success Index: Explanation and Clinical Context The PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) Success Index is a validated scoring system that predicts the likelihood of successful percutaneous coronary intervention (PCI) in patients with chronic total occlusion (CTO).
This score incorporates five angiographic variables that independently predict procedural difficulty and success:
1) Proximal cap ambiguity,
2) Lesion length ≥20 mm,
3) Severe calcification,
4) Bending >45°, and
5) CTO located in the right coronary artery (RCA).
Each variable contributes 1 point, resulting in a total score from 0 to 5. Higher scores indicate increased lesion complexity and a lower likelihood of procedural success.
In the original PROGRESS-CTO study, overall technical success exceeded 90% for lesions with scores 0–1 and declined progressively with higher scores, reaching approximately 50% for scores ≥4. The index helps interventional cardiologists assess lesion difficulty, plan strategy (antegrade vs. retrograde approach), and anticipate the need for advanced crossing techniques or specialized equipment.
Clinical Significance:
The PROGRESS-CTO Success Index complements other scoring systems such as the J-CTO and CASTLE scores. Its simplicity and reliance on angiographic features make it particularly useful in procedural planning and case selection for complex CTO interventions.
Reference:
Christopoulos G, Kandzari DE, Yeh RW, et al. Development and Validation of a Scoring System for Predicting Periprocedural Success in Percutaneous Coronary Intervention of Chronic Total Occlusions: The PROGRESS CTO Score.J Am Coll Cardiol Intv. 2016;9(1):1–9. doi:10.1016/j.jcin.2015.09.022