Incidence, determinants and consequences of left atrial remodelling after a first anterior myocardial infarction

Left atrial (LA) volume is an important predictor of mortality and morbidity after myocardial infarction (MI). However, the process of LA remodelling has not been extensively investigated.

Our purpose was to analyse the incidence, determinants and consequences of LA remodelling in a cohort of patients with a first anterior MI enrolled in the modern era of MI management.

We used data from 246 patients with a first anterior MI who were included in a prospective study on left ventricular (LV) remodelling (REVE-2). Serial echocardiographic studies were performed before discharge and at 3 months and 1 year after MI.

LA volume increased from 20.5±5.9 mL/m2 at baseline to 24.6±7.4 mL/m2 at 3 months (P<0.0001 versus baseline) and 25.4±7.6 mL/m2 at 1 year (P<0.0001 versus baseline). Patients with high LA volumes at baseline had higher LV volumes, decreased LV systolic function, increased E/Ea (early transmitral velocity/mitral annular early diastolic velocity ratio) and increased B-type natriuretic peptide concentration. By multivariable analysis, the sole independent predictor of change in LA volume from baseline to 1 year was peak creatine kinase concentration (P<0.0001). Patients with higher LA volumes at baseline were at higher risk of cardiovascular death or rehospitalization for heart failure during follow-up (P=0.015).

Despite modern therapeutic management, LA remodelling is common during the first 3 months after anterior MI. Patients with larger infarct size are at greater risk of LA remodelling after discharge.