Impact of Periprocedural Myocardial Injury and Infarction Definitions on Long-Term Mortality After Chronic Total Occlusion Percutaneous Coronary Intervention

Background: The prognostic implications of biomarker elevation following percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) lesions remain controversial. This study assessed the association of periprocedural myocardial injury and clinically relevant definition of periprocedural myocardial infarction with subsequent outcomes after CTO-PCI. Methods: We enrolled consecutive patients between January 2010 and December 2013 who underwent CTO-PCI at a large-volume center with serial CK-MB (creatine kinase–myocardial band) or cTnI (cardiac troponin I) measurements. The primary outcome was 5-year cardiovascular death. Results: A total of 2616 patients (2691 CTOs) with postprocedural CK-MB or cTnI undergoing PCI recanalization were included, per-lesion technical success rate was 74.4%. Postprocedural CK-MB and cTnI elevation occurred in 5.6% and 65.5% patients, respectively. For 2485 patients with serial CK-MB measurements, only postprocedural peak CK-MB ≥5× upper reference limit was associated with increased 5-year cardiovascular death (adjusted hazard ratio, 9.88 [95% CI, 3.06–31.9]). In contrast, for 1233 patients with serial cTnI measurements, no such association was present in any threshold. The Society for Cardiovascular Angiography and Interventions definition of periprocedural myocardial infarction was associated with 5-year cardiovascular death (adjusted hazard ratio, 8.45 [95% CI, 3.58–20.0]), whereas the ARC-2 (Academic Research Consortium-2) and fourth UDMI (Universal Definition of Myocardial Infarction) were not. Conclusions: In a large cohort of CTO-PCI, moderate to high levels of peak postprocedural CK-MB were prognostically significant, whereas such association was not observed in postprocedural cTnI. The Society for Cardiovascular Angiography and Intervention criteria (but not ARC-2 and fourth UDMI) were identified as clinically relevant periprocedural myocardial infarction definition following CTO-PCI. Graphic Abstract: A graphic abstract is available for this article.