Giuseppe Panuccio, Gerald S. Werner, Salvatore De Rosa, Daniele Torella, Yasuhiro Ichibori, Nicole Carabetta, Carsten Skurk, Patrick T. Siegrist, David M. Leistner, Ömer Göktekín, Kambis Mashayekhi, Ulf Landmesser, Youssef S. Abdelwahed
Coronary calcium significantly increases complexity in chronic total occlusion percutaneous coronary intervention (CTO-PCI). Coronary computed tomography angiography (CCTA) enables precise CTO assessment. However, no prior study has proposed a CCTA-based morphological classification of calcium patterns and assessed its procedural impact. To propose and validate a novel seven-point CCTA-derived classification of calcium morphology, ranging from "spot" (≤ 10% cross-sectional area, CSA) to "full moon" (100% CSA). We retrospectively included 167 patients undergoing CTO-PCI with prior CCTA. The primary endpoint was procedural failure. Secondary endpoints included coronary perforations, procedural and fluoroscopic time, and number of guidewires and balloons. A progressive, stepwise increase in procedural failure (from 6.2% in spot to 26.7% in full moon lesions; p = 0.007) and coronary perforation rates (from 3.1% in spot to 13.3% in full moon lesions; p = 0.03) was observed across the seven identified calcium patterns. In multivariable analysis, calcium severity was independently associated with procedural failure (OR 1.2 per step; 95% CI 1.01-1.52; p = 0.04). Increasing calcium severity was also independently associated with procedural time (B = + 4.7 min/step; p = 0.03), fluoroscopic time (B = + 2.2 min/step; p = 0.04), number of guidewires (B = + 0.30/step; p = 0.03) and balloons (B = + 0.31/step; p = 0.005). Full-scale progression from "spot" to "full moon" corresponded to + 33 min increase in procedural and + 14 min in fluoroscopic time. A novel CCTA-based calcium classification showed a strong, independent association with procedural failure and complexity. Its reproducibility and integration potential make it a valuable tool for enhancing planning and safety in CTO-PCI.