Calcium Modification Strategies in Treatment of Calcified Coronary Chronic Total Occlusions: Insights from the PROGRESS-CTO Registry

Background Coronary calcification increases the difficulty of chronic total occlusion (CTO) percutaneous coronary intervention (PCI), and various calcium modification strategies (CMS) are currently available to modify calcific plaque. (1,2) Purpose To describe the outcomes of PCI of calcified CTOs performed with and without CMS. Methods We analyzed data from 16,916 CTO PCIs enrolled in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) between 2012 and 2025. Results Moderate or severe calcification was present in 49.6% (n=8,385) and CMS was used in 9.4% (n=1,595) of CTO lesions. The most common CMS was rotational atherectomy (n=620), followed by intravascular lithotripsy (n=497), and laser atherectomy (n=292). Compared with non-CMS, CMS group had higher rates of successful antegrade wiring (63.3% vs. 44.2%; p<0.001) and technical success (94.4% vs 81.6%; p<0.001), with similar incidence of in-hospital major adverse cardiovascular events (MACE) (3.0% vs. 2.8%; p=0.657) and perforation (6.2% vs. 6.1%; p=0.933) (Figure 1). On multivariable analysis, the presence of moderate/severe calcification was independently associated with lower technical success (odds ratio, OR=0.77, 95% CI: 0.63-0.95) and higher MACE (OR=2.03, 95% CI: 1.51-2.74) (Figure 2). The use of CMS was also independently associated with higher technical success (OR=6.69, 95% CI: 4.57-10.0), but not MACE (OR=1.2, 95% CI: 0.85-1.68) (Figure 2). Conclusions Moderate/severe calcification was present in nearly half of CTO lesions, and was associated with lower technical success rates, and higher incidence of in-hospital MACE. The application of CMS in calcified CTOs was associated with higher technical success and similar MACE.