AIMS - Periprocedural myocardial injury (PMI) is frequently observed after percutaneous coronary interventions (PCI) for chronic total occlusion (CTO). We investigated the prognostic impact of PMI with the antegrade or the retrograde crossing technique.

METHODS AND RESULTS - A total of 1909 patients undergoing CTO PCI were stratified according to the presence/absence of PMI (elevation of cardiac troponin T [cTnT] >5x 99th percentile of normal), and divided according to tertiles of the difference between peak and baseline cTnT within 24 hours (ΔcTnT). The primary endpoint was all-cause mortality at a median follow-up of 3.1 (interquartile range 3.0-4.4) years. PMI occurred in 19.4% and 25.4% after antegrade (n=1447) and retrograde (n=462) procedures (p<0.001). PMI was significantly associated with mortality after antegrade (adjusted HR 1.39, 95% CI 1.02-1.88, p=0.04), but not retrograde CTO PCI (adjusted HR 0.93,95% CI 0.53-1.63, p=0.80, Pint=0.02). With the antegrade, but not the retrograde approach, mortality also increased with tertiles of ΔcTnT (T1: 11.0%, T2: 18.6%, T3: 21.6%, Log Rank p<0.001).

CONCLUSIONS - Periprocedural myocardial injury was significantly associated with all-cause mortality following antegrade, but not retrograde CTO PCI. Hence, the higher risk of PMI following retrograde procedures did not translated into worse survival.