Left Atrioventricular Coupling Index Predicts Poor Prognosis in Acute Myocardial Infarction: A Single-Center Cohort Study

(1) Background: The left atrioventricular coupling index (LACI) is a novel parameter for evaluating cardiac function. This study focused on its association with major adverse cardiovascular events (MACEs) in acute myocardial infarction (AMI) patients. (2) Methods: A retrospective cohort of AMI patients from Peking University First Hospital was enrolled. All underwent transthoracic echocardiography on admission for LACI measurement. The primary endpoint was MACE (a composite of nonfatal stroke, nonfatal myocardial infarction, and cardiovascular death). (3) Results: Among 843 AMI patients (62.07 ± 12.24 years, 77.94% male), the median LACI was 0.24 (IQR 0.18–0.33). During a median follow-up of 4.31 years, 151 patients (17.91%) developed MACE. The optimal LACI cutoff for risk stratification was 0.257. After multivariable adjustment, each standard deviation increase in LACI was associated with significantly elevated risks of MACE (HR 1.17, 95% CI 1.02–1.34), all-cause death (HR 1.19, 95% CI 1.05–1.35), cardiovascular death (HR 1.33, 95% CI 1.10–1.61), and stroke (HR 1.23, 95% CI 1.05–1.43). (4) Conclusions: LACI is an independent predictor of poor prognosis in AMI patients and may serve as a valuable tool for risk stratification in secondary prevention.