Integrating myocardial work and native T1 mapping after STEMI: uncovering the function-tissue relationship via advanced echocardiography and multiparametric CMR

Background Contemporary echocardiography enables comprehensive assessment of left ventricular (LV) performance. Myocardial work (MW) analysis integrates LV afterload into global longitudinal strain (GLS) and reflects myocardial oxygen consumption, allowing quantification of constructive, wasted, and overall work efficiency. Although MW has emerged as a promising tool in ST-elevation myocardial infarction (STEMI), its relationship with myocardial tissue characteristics remains insufficiently explored. We aime d tKey findings are summarized in Tables 1, 2, and 3.o investigate the association between cardiac magnetic resonance (CMR)-derived tissue markers—native T1 mapping, infarct size, myocardial salvage index (MSI), and microvascular obstruction (MVO)—and echocardiographic myocardial work indices one week after primary percutaneous coronary intervention (pPCI). Methods We included 36 consecutive patients (mean age 58 ± 11, 81% male) with STEMI successfully treated with pPCI. All underwent CMR and 2D speckle-tracking echocardiography on days 6–8 post-pPCI. CMR parameters were analyzed using CVI42 and included native T1 and T2 mapping, extracellular volume fraction (ECV), area at risk (AAR), infarct size (late gadolinium enhancement, LGE), and MVO. Echocardiographic indices were obtained using Automated Function Imaging: GLS, Global Work Index (GWI), Constructive Work (GCW), Wasted Work (GWW), and Work Efficiency (GWE). Spearman’s correlation analysis was used to explore relationships between myocardial work and tissue characteristics in infarcted, remote, and global LV myocardium. Results Key findings are summarized in Tables 1, 2, and 3. Conclusion Our findings suggest that myocardial work indices assessed by advanced echocardiography early after STEMI reflect underlying myocardial tissue alterations. Specifically, impaired constructive and global work are associated with elevated native T1 values and greater infarct burden, while increased wasted work correlates with diffuse myocardial abnormalities in the remote myocardium. These associations highlight the ability of myocardial work to capture both focal and diffuse myocardial injury, reinforcing its potential role as an integrative marker at the intersection of function and tissue characteristics. Further prospective studies are warranted to evaluate its prognostic value and potential for guiding individualized post-STEMI management.