Left atrial strain and distensibility in relation to left ventricular dysfunction and prognosis in aortic stenosis

To test the relationship between left atrial (LA) distensibility (LAD), LA strain (LAS), and left ventricular (LV) dysfunction and prognosis in aortic stenosis (AS).

Transthoracic Doppler echocardiography was performed prospectively in 102 consecutive patients with AS (77 with severe, 25 with moderate, mean age 77 years). LA volume was calculated by the area-length method in apical four- and two-chamber views, immediately before mitral valve opening (Vol_max ) and at mitral valve closure (Vol_min ). LAD was defined as (Vol_max  - Vol_min ) × 100%/Vol_min . LAS (mean of maximal strain from the 4-2 chamber views) was conducted using a dedicated software package. The endpoint was hospitalization for heart failure and death from any cause.

Left atrial strain, LAD, and LA vol/m² were significantly correlated with LV diastolic parameters, and PASP (all, P < 0.05). However, LAD and LAS but not LA vol/m² were significantly correlated with Charlson score, LV global longitudinal strain, and to transaortic mean gradient (all, P < 0.05). At a median follow-up of 25 months, 53 patients had an event. LAS, LAD, LA vol/m², and Charlson index were associated with events (all, P < 0.05). In multivariate analysis, LAD, LAS, and Charlson index (all, P < 0.01) remained independently associated with events. Using a ROC curve analysis, LAD ≤ 69% and LAS ≤ 17% were the best cutoffs associated with an event.

In patients with moderate to severe AS, LAD and LAS are associated with LV dysfunction, AS severity, and are independently linked to events.