Incremental prognostic value of hemodynamic forces using CMR to predict major adverse cardiovascular events in patients with MINOCA

Abstract Introduction Myocardial infarction with non-obstructive coronary arteries (MINOCA), considered here as a working diagnosis, accounts for 5–15% of acute myocardial infarctions (MI) and involves diverse pathophysiological mechanisms. Now recognized as associated with significant cardiovascular risk and mortality, its risk stratification remains challenging due to its heterogeneous aetiologies. Hemodynamic forces (HDFs), a novel parameter derived from standard non-contrast cine CMR images, quantify the energy exchange between the left ventricular (LV) wall and blood flow, and have demonstrated prognostic value in cardiomyopathies. However, their prognostic role in risk stratification for MINOCA patients remains unexplored. Objective We aimed to investigate whether specific HDF parameters are independently associated with major adverse cardiovascular events (MACE) in a consecutive cohort of patients presenting with MINOCA. Methods In this single-centre study, patients admitted for MINOCA who underwent 3T CMR were retrospectively included. Final diagnoses were established based on clinical, biological, coronary angiographic, and CMR data. HDF parameters were computed using dedicated post-processing software. The primary composite endpoint was MACE including: heart failure hospitalisation, non-fatal MI, ventricular or supraventricular arrhythmia at one year, and all-cause mortality defined using the French national death registry (INSEE). Results A total of 369 patients (age 48 ± 21 years, 63% male) were included in the final analysis with the following diagnoses: myocarditis (48%), ischemic injury (21%), Takotsubo syndrome (9%), cardiomyopathy (8%), and normal (14%). The mean left ventricular ejection fraction (LVEF) was 55.3 ± 10.3%. After a median follow-up of 5.2 ± 2.9 years, 47 (13%) patients experienced MACE. Using logistic regression, LV diastolic transverse HDF, which reflects the energy exchange along the anterior-inferior and septal-lateral axes during diastole, was significantly associated with MACE (odd-ratio [OR] = 0.68, p=0.019). In multivariable analysis adjusted for traditional CMR prognostic factors (LVEF and late gadolinium enhancement [LGE] extent), diastolic transverse HDF remained an independent predictor of MACE (adjusted OR = 0.71, p=0.036). This association remained significant after additional adjustment for gender (adjusted OR = 0.70, p=0.026). Regarding incremental prognostic value to predict MACE, adding diastolic transverse HDF to the baseline model including LVEF, LGE extent and gender, significantly improved the C-index from 0.75 to 0.79 (C-index improvement = +0.04, p=0.035) (Figure 1). Conclusion In MINOCA patients, LV diastolic transverse HDF is independently associated with MACE, with an incremental prognostic value above traditional prognostic markers. These findings suggest that HDF analysis could represent a promising tool to enhance risk stratification in this complex and heterogeneous population.