Prognostic implication of unrecognized myocardial infarction in patients with non-ST-segment-elevation acute coronary syndrome

• Published in: European heart journal Vol. 43; no. Supplement_2
• Main Authors: Sayama, K, Hoshino, M, Kanaji, Y, Sugiyama, T, Misawa, T, Hada, M, Nagamine, T, Nogami, K, Teng, Y, Ueno, H, Matsuda, K, Yonetsu, T, Kakuta, T
• Format: Journal Article
• Language: English
• Published: 03.10.2022
• ISSN: 0195-668X; 1522-9645
• DOI: 10.1093/eurheartj/ehac544.287

Abstract Background Prognostic value of unrecognized non-infarct-related territory (non-IR) myocardial infarction (UMI) in patients with non-ST-segment-elevation acute coronary syndrome (NSTE-ACS) remains to be elucidated. Purpose This study sought to evaluate the prevalence of non-IR UMI and its prognostic value in patients with first NSTE-ACS presentation. Methods This retrospective single-center analysis was conducted in patients with NSTE-ACS without prior history of coronary artery disease, who underwent uncomplicated urgent percutaneous coronary intervention (PCI) within 48 hours of admission between August 2014 and January 2018. All patients underwent postprocedural cardiac magnetic resonance imaging (CMR) within 30 days after PCI. Non-IR UMI was defined as the presence of non-IR delayed gadolinium enhancement with an ischemic distribution pattern. We investigated the association of non-IR UMI, other CMR findings and baseline clinical characteristics with major adverse cardiac events (MACE), defined as all-cause death, non-fatal myocardial infarction, ischemic stroke, late revascularization and hospitalization for congestive heart failure. Results A total of 168 NSTE-ACS patients were included (124 males (73.8%); 66±11 years). Non-IR UMI was detected in 28 patients (16.7%). During a median follow-up of 32 months (15–58), MACE occurred in 10 (35.7%) patients with non-IR UMI, and 20 (14.3%) patients without (P=0.013). Patients with MACE showed higher frequency of non-IR UMI in RCA territory and multi vessel disease, higher level of NT-proBNP at admission, higher Genisini score, and greater extent of UMI. Cox's proportional hazards analysis showed that the presence of non-IR UMI was an independent predictor of MACE (HR 2.34, 95% CI 1.02–5.37, P=0.045), after adjusting confounding factors, such as multi vessel disease and serum levels of NT-proBNP at admission. The discriminant efficacy (IDI and NRI) of predicting MACE was significantly improved when the presence of non-IR UMI added to the reference clinical risk model. Kaplan-Meier analysis revealed that patients with non-IR UMI were significantly associated with poor prognosis. (Figure 1). Conclusions In patients with NSTE-ACS undergoing urgent PCI, the prevalence of non-IR UMI was 16.7%. Non-IR UMI provided prognostic information independent of conventional risk factors. Funding Acknowledgement Type of funding sources: None.