Left atrial strain quantified after myocardial infarction is associated with early left ventricular remodeling

Left ventricular remodeling (LVR) is common and associated with adverse outcome after ST-elevation myocardial infarction (STEMI). We aimed to investigate the association between left atrial (LA) mechanical function using speckle tracking imaging and early LVR at follow-up in STEMI patients.

Baseline 3D thoracic echocardiograms were performed within 48 h following admission and at a median follow-up of 7 months after STEMI. A > 20% increase in the left ventricular (LV) end-diastolic volume compared to baseline at follow-up was defined as LVR. LA global longitudinal strain was evaluated for the reservoir, conduit, and contraction (LASct) phases.

A total of 121 patients without clinical heart failure (HF) were prospectively included, between June 2015 and October 2018 (age 58.3 ± 12.5 years, male 98 (81%)). Baseline and follow-up LV ejection fraction (LVEF) were 46.8% [41.0, 52.9] and 52.1% [45.8, 57.0] respectively (p < .001). Compared to other patients, those with LVR had significantly lower values of LASct at baseline (-7.4% [-10.1, -6.5] vs. -9.9% [-12.8, -8.1], p < .01), both on univariate and baseline LV volumes-adjusted analyses. Baseline LA strain for reservoir and conduit phases were not associated with significant LVR at follow-up. Intra- and interobserver analysis showed good reproducibility of LA strain.

Baseline LASct may help identifying patients without HF after STEMI who are at higher risk of further early LVR and subsequent HF and who may benefit from more intensive management.