Contemporary Outcomes of the Retrograde Approach to Chronic Total Occlusion Interventions: Insights from an International CTO Registry.

AIMS: The retrograde approach is critical for achieving high success rates in chronic total occlusion (CTO) percutaneous coronary intervention (PCI), but has been associated with higher risk of complications. METHODS AND RESULTS: We compared the technical and procedural outcomes of retrograde (n=1,515) and antegrade-only CTO PCIs (n=2,686) in a contemporary multicenter CTO registry. The mean age of patients undergoing retrograde PCI was 65±10 years and 86% were men, with high prevalence of prior myocardial infarction (51%), prior PCI (71%), and coronary artery bypass graft surgery (45%). The mean J-CTO (3±1 vs 2±1 p<0.001) was higher in retrograde PCIs. The most commonly used collateral channels were septals (65%), epicardials (32%), saphenous venous grafts (14%) and left internal mammary artery grafts (2%). Overall technical (79% vs 91%, p<0.001) and procedural (75% vs 90%, p<0.001) success rates were lower with the retrograde approach, and patients had higher in-hospital major complications rate than antegrade-only PCIs (5.1% vs 0.8%, p<0.001), due to higher mortality (1.1% vs. 0.1%, p<0.001), acute myocardial infarction (1.9% vs 0.2%, p<0.001), repeat-PCI (0.7% vs 0.1%, p=0.001), and pericardiocentesis (1.7% vs 0.3%, p<0.001). CONCLUSIONS: In summary, retrograde approach to CTO PCI is performed in higher complexity lesions and is associated with lower success and higher major complications rates.