While use of retrograde CTO PCI via epicardial collaterals declined over time, crossing success improved without a significant increase in complications, suggesting improved case selection and procedural expertise.
Use of the retrograde approach overall and via epicardial collaterals decreased significantly over time in CTO PCI.
Epicardial collateral crossing success increased significantly over the study period.
In-hospital major adverse cardiac events (MACE) occurred in 3.8% of epicardial collateral CTO PCI cases and did not change significantly over time.
Coronary perforation occurred in 13.8% of epicardial collateral CTO PCI procedures and was strongly associated with MACE.
The study population was predominantly male, older, and had high lesion complexity.
This research examined trends over 14 years in a specific high-risk technique used during procedures to open completely blocked coronary arteries (chronic total occlusions, or CTOs). The technique, called retrograde crossing via epicardial collaterals, involves approaching the blockage from the back end through small natural bypass vessels that run along the surface of the heart. The study analyzed 1,527 such cases from 49 hospitals worldwide, finding that while this particular approach became less commonly used over time, operators became better at successfully crossing these collateral vessels when they did use them, and serious complication rates did not significantly worsen. The most important safety finding was that tears or punctures in coronary arteries (coronary perforations) occurred in nearly 1 in 7 procedures (13.8%), and when perforations happened, the rate of serious in-hospital complications jumped from 2% to over 15%. Overall, serious complications occurred in about 1 in 26 cases (3.8%), which is notable given that these were among the most complex blocked artery cases, with high average difficulty scores. This research suggests that experienced CTO programs are becoming more selective about when to use epicardial collaterals—reserving them for cases where other approaches are not available—while simultaneously improving their technical skill with the technique. The strong link between coronary perforation and serious outcomes highlights that preventing perforations remains a critical safety priority when this approach is used.
Vichos T, Strepkos D, Alexandrou M, Carvalho P, Fath A, Goel M, et al.. (2026). Temporal trends in retrograde crossing of epicardial collaterals in chronic total occlusion percutaneous coronary intervention.. International journal of cardiology. https://doi.org/10.1016/j.ijcard.2026.134586