No block, still shock: the role of strain echocardiography in MINOCA evaluation

Abstract Background Myocardial infarction with non-obstructive coronary arteries (MINOCA) presents a diagnostic and therapeutic challenge, as patients exhibit clinical features of myocardial infarction (MI) without significant coronary obstruction on angiography. Strain echocardiography, specifically left ventricular global longitudinal strain (LV-GLS), may provide added value in detecting subclinical myocardial dysfunction in this population. Purpose To evaluate the clinical characteristics of patients with MINOCA and assess the diagnostic and prognostic utility of strain echocardiography. Methods A total of 287 patients presenting with acute coronary syndrome (ACS) and undergoing coronary angiography between January and June 2024 were included. Patients were categorized into three groups based on angiographic findings: MI with obstructive coronary arteries (MIOCA; ≥50% stenosis, n=237), MINOCA (<50% stenosis, n=50), and a control group with ischemia and non-obstructive coronary arteries (INOCA; n=50). Laboratory data, conventional echocardiography, and LV-GLS measurements were recorded at admission and at a 3-month follow-up. Results The MIOCA group was older (60.2±11 years) and predominantly male (79.7%) compared to MINOCA (49.9±19 years, 54%) and INOCA (48.7±13 years, 48%) (p<0.001). LV ejection fraction (EF) and LV-GLS were significantly lower in MIOCA than MINOCA at baseline (p<0.001 and p=0.007, respectively). At 3 months, EF remained lower in MIOCA (p<0.001), but LV-GLS was comparable between groups (p=0.29). Neutrophil-to-lymphocyte ratio (NLR), neutrophil-to-platelet ratio (NPR), glucose, and HbA1c were significantly higher in MIOCA; NPR and glucose were independent predictors of impaired LV-GLS (<–16) in MINOCA. An NPR >0.02 predicted LV-GLS <–16 with 85% sensitivity and 81% specificity, and glucose >108 mg/dL predicted the same with 61% sensitivity and 75% specificity (p<0.001). Conclusion Despite preserved EF, MINOCA patients showed comparable LV-GLS impairment to MIOCA patients, indicating subclinical myocardial dysfunction. LV-GLS may offer superior diagnostic sensitivity over EF, and inflammatory and glycemic markers could guide early risk stratification and targeted therapies in MINOCA.LVEF at Baseline and 3 Months  LV-GLS at Baseline and 3 Months