Incidence of MINOCA in the high-sensitivity troponin era: a meta-analysis

Abstract Background and Aim Myocardial infarction with non-obstructive coronary arteries (MINOCA) is often under-recognised in clinical practice. The reported incidence of MINOCA was estimated to be 6% of MI presentations by Pasupathy et al. in the era preceding adoption of high sensitivity troponin assays. We sought to investigate the incidence of MINOCA in the high-sensitivity troponin era as compared to incidence of MINOCA during the era of traditional cardiac biomarkers (standard troponin assays, CK, CK-MB). Methods A prospective systematic review and meta-analysis using MEDLINE and EMBASE to capture relevant papers from 1996-2022 was performed. Papers detailing incidence of MI-CAD and MINOCA as well as the utilised biomarkers were included. Patient demographics, presentation and recorded biomarkers were also analysed for pre-specified analysis. Results 47 studies detailing the results of 667 850 patients were included. 53 586 patients were identified to have MINOCA with a mean weight incidence of 9.1% (7.3-11.3, 95% CI). MI-CAD patients were more likely to be male (68.5% vs 39.3%, RR (0.59, 0.74)) and had higher incidence of traditional cardiac risk factors. Notably chronic kidney disease was not associated with higher incidence of MICAD over MINOCA (RR 0.72, 0.5-1.03). There were no significant trends in incidence of MINOCA according to median year of study recruitment (ß=-0.18, (-0.76, 0.4) p=0.537). MINOCA patients were more likely to present as NSTEMI (14.5% (11.3-18.3, 95%CI)) rather than STEMI (3.5% (2.7-4.7%)). MINOCA patients had lower cardiac biomarker elevations than patients with MICAD. Conclusions The incidence of MINOCA higher than previously estimated in the era of high sensitivity troponin. MINOCA patients are less likely to have traditional cardiac risk factors and more likely to present with NSTEMI and smaller cardiac biomarker elevations than patients with MI-CAD.MINOCA RateMINOCA vs MI-CAD Risk Factors