The combined effect of arterial hypertension and coronary microvascular dysfunction in the prognosis of patients with ST-segment elevation myocardial infarction: a real-world study

Despite successful primary percutaneous coronary intervention (PPCI), a substantial proportion of patients with ST-segment elevation myocardial infarction (STEMI) still develop coronary microvascular dysfunction (CMD), which is closely associated with adverse outcomes. Arterial hypertension (AH) was also associated with adverse outcomes in patients with STEMI. However, the combined prognostic value of AH and CMD in patients with STEMI remains unclear. This study aimed to assess the combined impact of AH and CMD on prognosis in patients with STEMI using the coronary angiography-derived index of microcirculatory resistance (angio-IMR).

In this retrospective, two-center study, 910 patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) were enrolled from July 2019 to August 2023. The follow-up endpoint was major adverse cardiovascular event (MACE), defined as all-cause mortality, non-fatal myocardial infarction, ischaemia-driven target vessel revascularisation (TVR), and new-onset heart failure. Kaplan-Meier analysis and Cox proportional hazards models were used to evaluate the associations of AH and coronary microvascular dysfunction with MACE. A restricted cubic spline plot was used to explore the nonlinear relationship between angio-IMR and MACE. Receiver operating characteristic curves were plotted to compare their predictive performance. Net weight classification index (NRI) and comprehensive discriminant improvement index (IDI) were used to evaluate the incremental predictive value.

Patients with AH exhibited a higher 1-year incidence of MACE compared with non-AH patients (17.4% vs. 10.1%, P < 0.001). Among STEMI patients, those with concomitant CMD and AH showed the highest cumulative incidence of MACE (22.7%, P < 0.001). After adjusting for confounding factors, the coexistence of AH and CMD emerged as the strongest predictor of MACE among STEMI patients (hazard ratio [HR]: 3.79, 95% confidence interval [CI]: 2.009–7.146, P < 0.001). The combined model of AH and CMD demonstrated superior predictive performance compared with models including AH alone (AUC: 0.682, 95% CI: 0.675–0.689) or CMD alone (AUC: 0.703, 95% CI: 0.697–0.709), yielding the highest diagnostic efficacy (AUC: 0.713, 95% CI: 0.707–0.719). The joint model showed significant improvements in discrimination (C statistic increased from 0.699 to 0.736, P < 0.001) and reclassification (NRI = 0.142, IDI = 0.024, both P < 0.05).

In STEMI patients undergoing PPCI, AH combined with CMD is closely associated with a higher risk of MACE and it helps to improve the risk stratification of these patients.