Impact of a CTO in a non-infarct-related artery on long-term mortality in patients undergoing primary PCI

Abstract

Background Previous studies showed increased mortality rates in patients with ST-elevation myocardial infarction (STEMI) and a chronic total occlusion (CTO) in a non-infarct-related artery, but long-term data are scarce. Purpose Our aim was to assess all-cause mortality during 5 years follow-up in patients with a remaining nonculprit CTO after being treated with primary PCI. Methods The study included 9504 patients admitted for primary PCI during 2009–2019, with available baseline angiography, from an electronic, prospective registry of a high-volume catheterization laboratory. Kaplan Meier cumulative mortality curves for non-culprit CTO vs. no CTO were compared with the log-rank test, with landmarks set at 30 days and then annually up to 5 years follow-up. Adjusted Cox regression models were constructed to assess 30-day and 5-year mortality risk of a non-culprit CTO. Median follow-up was 1507 days. Results Nonculprit CTO was present in 13.2% of patients (n=1253). Presence of a nonculprit CTO was associated with older age (64 vs. 61, p<0.001), more frequent history of cardiovascular disease including prior MI (33% vs. 14%, p<0.001), stroke (10.3% vs. 5.9%, p<0.001) and CABG (10.5% vs. 1.5%, p<0.001), higher rates of renal failure (10.7% vs. 4.8%, p<0.001), as well as more often Killip class 2–4 on admission (29% vs. 16%, p<0.001) and a lower ejection fraction (40% vs. 47%, p<0.001). Crude mortality rates were significantly increased in patients with a nonculprit CTO vs. no CTO, at both 30 days (15.7% vs. 5.6%, p<0.001) and 5 years (54.6% vs. 27.9%, p<0.001). After adjusting for the observed baseline differences, nonculprit CTO was still associated with an elevated mortality risk at both 30-days (HR 1.5, CI95% 1.1–1.9, p=0.007) and 5 years (HR 1.6, CI95% 1.4–1.9, p<0.001). Landmark analyses showed continuously increasing risk of mortality in the presence of a nonculprit CTO, as compared with primary PCI-treated patients with no CTO (30 days to 1 year 11.4% vs. 4.9%, p<0.001; 1st to 2nd year of follow-up 6.3% vs. 3.4%, p<0.001; 2nd to 3rd year 6.2% vs. 2.8%, p<0.001; 3rd to 4th year 7.4% vs. 3.0%, p<0.001; and 4th to 5th year 5.2% vs. 3.6%, p=0.1). Conclusions Presence of a nonculprit CTO is independently associated with 5-year mortality after primary PCI. Importantly, the mortality risk increases continuously with an average annual absolute difference of 3%, in patients with a nonculprit CTO vs. those with no CTO. Nonculprit CTO vs. no CTO Funding Acknowledgement Type of funding source: None