The study by Acharya et al1 in this issue of JAMA Cardiology is an extension of the authors’ previous work in 20122 reporting the outcomes of individuals with clinically unrecognized myocardial infarction (UMI) detected by cardiac magnetic resonance (CMR), compared with the outcomes of patients with previously diagnosed and thus recognized myocardial infarction (RMI). These investigators from the United States and Iceland now provide data on mortality, incident MI, and incident heart failure up to 13.3 years after baseline CMR to determine the presence and extent of previous MI. A unique aspect of this long-term study is the 100% completeness of follow-up, with data available in all 935 participants of the elderly Icelandic cohort. The authors demonstrate that UMI is associated with overall short-term mortality lower than that of RMI; however, with longer-term follow-up, mortality rates of those with UMI and RMI are equivalent.