Impact of stress hyperglycemia ratio on periprocedural myocardial infarction in patients with NSTEMI

Background Stress hyperglycemia ratio (SHR), a new marker that reflects the true metabolic hyperglycemic state of patients regardless of the presence of diabetes mellitus, is strongly associated with adverse clinical outcomes in patients with acute myocardial infarction (AMI). However, studies on the impact of SHR on peri-procedural (type 4a) myocardial infarction (MI) are limited. Purpose The aim was to elucidate the relationship between SHR and type 4a MI in patients presenting with non-ST-segment elevation myocardial infarction (NSTEMI) undergoing percutaneous coronary intervention (PCI). Methods We evaluated consecutive patients with NSTEMI, both diabetic and non-diabetic, who underwent PCI and exhibited stable (≤20% variation) or falling pre-procedure baseline cardiac troponin values and with sampled glycated hemoglobin available during hospitalization. Using receiver operating characteristic (ROC) curves, we categorized patients into two groups (higher SHR and lower SHR) based on the value associated with the highest Youden index. Subsequently, we assessed the incidence of type 4a MI in these two groups. Finally, we conducted Cox regression analyses to determine the independent prognostic impact of SHR on the risk of developing type 4a MI. Results We identified a threshold value of SHR=1.14 using ROC curves (AUC=0.684). The final study population comprised 837 patients with NSTEMI who underwent PCI, with 362 patients exhibiting SHR >1.14 at hospital admission. At baseline, patients with SHR >1.14 were older and had more comorbidities, including hypertension, diabetes, chronic kidney disease, and atrial fibrillation. Regarding coronary angiography and PCI characteristics, patients with higher SHR exhibited more frequent multivessel disease and consequently underwent more complex PCI procedures. Patients with SHR >1.14 developed type 4a MI more frequently than those with lower SHR (27.6% vs. 9.7%, p<0.001). Cox regression analysis demonstrated that, after adjusting for major comorbidities and complex PCI, the presence of SHR >1.14 at admission independently predicted a higher risk of type 4a MI after PCI in NSTEMI patients (OR=3.36; 95% CI 2.23 - 5.13; p<0.001). The adverse prognostic impact of higher SHR was further confirmed concerning in-hospital and long-term outcomes. Conclusions In patients presenting with NSTEMI undergoing PCI, elevated SHR (>1.14) at hospital admission is strongly associated with an increased risk of type 4a MI post-PCI, independent of major comorbidities and procedural complexity. These findings underscore the importance of SHR as a valuable prognostic tool in risk-stratifying patients with NSTEMI undergoing PCI, suggesting its potential utility for optimizing patient management strategies and improving clinical outcomes.