Cardiovascular Magnetic Resonance-Derived Left Atrioventricular Coupling Index for Predicting Adverse Cardiac Outcomes in Patients with Ischemic Cardiomyopathy

ABSTARCT Background Risk stratification in ischemic cardiomyopathy (ICM) traditionally relies on left ventricular ejection fraction (LVEF), which may not fully demonstrate the complex interplay between atrium and ventricle. The left atrioventricular coupling index (LACI) has emerged as a promising integrative marker. This study evaluated the prognostic value of cardiovascular magnetic resonance (CMR)-derived LACI in patients with ICM. Methods This retrospective cohort study included 276 patients with ICM (mean age 65±12 years and 80% male) who underwent CMR. LACI was calculated as LAEDV/LVEDV. The primary endpoint was a composite of cardiovascular mortality, non-fatal myocardial infarction, heart failure hospitalization (HFH), and major ventricular arrhythmic events. Secondary endpoints included individual components of the primary endpoint and all-cause mortality. Optimal LACI cut-off values were determined using receiver operating characteristic (ROC) analysis. Results During a median follow-up of 3.2 years, the primary endpoint occurred in 100 patients (36.2%). The optimal LACI cut-off for predicting the primary outcome was 0.35. Patients with LACI ≥ 0.35 had a significantly higher incidence of the primary outcome compared to those below the threshold (52.3% vs. 31.3%; p=0.002). In multivariate Cox regression analysis, LACI ≥0.35 was an independent predictor of the primary outcome (aHR 1.83; 95%CI 1.06–3.16; p=0.029). Among secondary endpoints, LACI ≥ 0.35 was strongly associated with HFH (aHR 3.33; 95%CI 1.58–6.72; p <0.001), though it did not reach statistical significance for mortality. Conclusions CMR-derived LACI is an independent predictor of adverse cardiovascular outcomes, particularly HFH, in patients with ICM.