Unrecognized myocardial infarction carries similar prognosis to recognized myocardial infarction

Reference

Yang Y, Wensheng L, Zhu H, et al. Prognosis of unrecognised myocardial infarction determined by electrocardiography or cardiac magnetic resonance imaging: systematic review and meta-analysis. BMJ 2020;369:m1184.

Synopsis

These researchers searched 3 databases and reference lists of included studies to identify 30 prospective cohort studies of 253,425 adults with unrecognized MI and other cardiovascular risk factors detected at baseline. Unrecognized MI was identified by electrocardiogram in 20 studies and by CMRI in 10 studies. An unrecognized MI identified by electrocardiogram was associated with increased risks of all-cause mortality (hazard ratio [HR] 1.50; 95% CI 1.3 - 1.73), cardiovascular mortality (HR 2.33; 1.66 - 3.27), and increased major adverse cardiac events (HR 1.61; 1.38 - 1.89). Rates were higher when the unrecognized MI was identified by CMRI: all-cause mortality (HR 3.21; 1.43 - 7.23), cardiovascular mortality (HR10.79, 4.09 - 28.42), and major adverse cardiac events (HR 3.23; 21.0 - 4.95). All but 2 of the studies were graded as high quality. There was significant heterogeneity among the results of studies for all-cause mortality and major adverse cardiac events for CMRI.