Prognostic value of left atrioventricular coupling index in heart failure

To investigate the distribution of left atrioventricular coupling index (LACI) among patients with heart failure and left ventricular ejection fraction (LVEF) < 50% and to explore its association with the combined endpoint of all-cause death or HF hospitalization at long-term follow-up.

Patients with HF and LVEF < 50% undergoing cardiac magnetic resonance were evaluated. Patients with atrial fibrillation or flutter were excluded. Left atrioventricular coupling index was measured as the ratio between the left atrial (LA) and the LV end-diastolic volumes. Patient population was divided according to LACI tertiles and followed up. Total of 478 patients (mean age 62 ± 12 years, 78% male) were included. The median value of LACI was 27.1% (interquartile range 19.9-34.5). Patients within the worst LACI tertile (≥30.9%) showed smaller LV volumes and larger LA volumes as compared with patients in the first or second tertile (LACI 6.2-22.2 and LACI 22.3-30.9, respectively). Left atrioventricular coupling index was significantly associated with the combined endpoint [hazard ratio (HR) 1.87, P = 0.01]. After adjusting for sex, age, ischaemic HF aetiology, LVEF, LA reservoir strain, diabetes mellitus, LV scar, mitral regurgitation, and LVEDVi, LACI remained significantly associated with the combined endpoint (HR 1.77, P = 0.02). Patients with the highest LACI values had worse outcomes compared with patients in first and second tertiles (HR 1.69, P = 0.02 and HR 1.77, P = 0.02, respectively).

In patients with HF and LVEF <50%, LACI is independently associated with adverse events. Patients with most impaired left atrioventricular coupling have the worst clinical outcomes.