Prognostic value of extracellular volume fraction in myocardial infarction and myocardial infarction with nonobstructive coronary arteries: A multicenter study.

Rationale And Objectives: The aim of the present retrospective study was to evaluate the prognostic role of the extracellular volume fraction (ECV) in patients with myocardial infarction (MI) and myocardial infarction with nonobstructive coronary arteries (MINOCA). The present study hypothesized that ECV is associated with major adverse cardiovascular events (MACEs) in MI and MINOCA patients.

Materials And Methods: Cardiac magnetic resonance (CMR) imaging was performed on 351 consecutive patients (mean age: 58 ± 12 years; 252 [71.8%] males) who were diagnosed with MI between October 2015 and November 2023. From CMR imaging, the extent of late gadolinium enhancement (LGE), native T1 and ECV were derived. Patients were categorized into groups according to the degree of coronary artery stenosis, namely, patients with MINOCA and patients with obstructive MI. Follow-up was performed to assess MACEs.

Results: The final cohort consisted of 61 MINOCA patients and 290 obstructive MI patients. During a mean follow-up of 27 ± 16 months, there was no statistically significant difference in the incidence of MACEs between patients with MINOCA and those with obstructive MI, and the two groups of patients had similar ECVs (32.2 ± 3.6 vs. 32.3 ± 6.0, p = 0.864). According to the multivariate Cox regression, ECV was an independent predictor of MACEs (HR: 1.13; p < 0.001) and significantly improved the prognostic value of the baseline multivariate models (C-statistic improvement: 0.816-0.864, p = 0.001). Similarly, ECV maintained an independent association with MACEs in the MINOCA (HR: 1.35; p < 0.001) and obstructive MI (HR: 1.13; p < 0.001) groups.

Conclusion: In MI and MINOCA patients, ECV is an independent predictor of MACEs. MINOCA is not a benign disease, and its long-term prognosis is as poor as that of patients with obstructive MI.