280The Impact of Epicardial Collateral Use on the Outcomes of Retrograde Chronic Total Occlusion Percutaneous Coronary Intervention

Abstract Background The impact of the type of collateral vessel used on the outcomes of retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. Methods We reviewed the baseline clinical and angiographic characteristics and procedural outcomes of 1,501 retrograde CTO PCIs performed in 1494 patients between 2012 and 2019 at 26 centres. Purpose We sought to examine the impact of the type of collateral vessel used on the outcomes of retrograde CTO PCI. Results Mean patient age was 65.0±10 years and 86% were men. Septal collaterals or bypass grafts were used in 66%, epicardial collaterals in 34% of lesions. Compared with cases in which only septal collaterals and bypass grafts were used, use of epicardial collaterals were associated with larger vessel diameter (3.0 [2.5; 3.0] vs. 3.0 [2.5, 3.2] mm, p=0.005), more moderate/severe tortuosity (55% vs. 42%, p<0.0001), more moderate/severe calcification (73% vs. 65%, p=0.002), and higher Japan chronic total occlusion score (3.34±1.02 vs. 3.11±1.07, p<0.0001). Epicardial collateral use was associated with lower technical (76.3% vs. 80.6%, p=0.053) and procedural (71.9% vs. 77.8%, p=0.011) success rates, but similar incidence of major cardiac adverse events (4.72% vs. 4.56%, p=0.889). Epicardial collaterals were associated with more perforations (10.63% vs. 7.30%, p=0.028). Epicardial collateral use was associated with longer fluoroscopy time (82 [64, 104] 76 [(55, 102] p=0.0003) and higher contrast volume (300 [221; 414] ml vs. 270 [200; 370] ml, p<0.0001). Conclusion In a contemporary, multicenter registry epicardial collaterals were used in approximately one-third of retrograde CTO PCIs. Use of epicardial collaterals was associated with lower success but similar major complication rates. Acknowledgement/Funding Minneapolis Heart Institute Foundation