Left Ventricular Myocardial Work in Patients with Severe Aortic Stenosis

Left ventricular myocardial work (LVMW) is a novel method to assess left ventricular (LV) function using pressure-strain loops that takes into consideration LV afterload. The estimation of LV afterload in patients with severe aortic stenosis (AS) may be challenging, and no study so far has investigated LVMW in this setting. The aim of this study was to develop a method to calculate LVMW in patients with severe AS and to analyze its relationship with heart failure symptoms.

Indices of LVMW were calculated in 120 patients with severe AS who underwent transcatheter aortic valve replacement and invasive LV and aortic pressure measurements. LV systolic pressure was also derived by adding the mean aortic valve gradient to the aortic systolic pressure. LV global longitudinal strain and echocardiography-derived LV systolic pressure were then incorporated to construct pressure-strain loops of the left ventricle.

An excellent correlation was observed between LVMW indices calculated using the invasive and echocardiography-derived LV systolic pressure. Patients in New York Heart Association functional class III or IV (n = 97 [73%]) had lower LV global longitudinal strain, LV global work index, LV global constructive work, and right ventricular free wall strain compared with those in New York Heart Association functional class I or II. In contrast to LV global longitudinal strain, LV global work index (odds ratio per 100 mm Hg% increase, 0.91; 95% CI, 0.85-0.98; P = .012) and LV global constructive work showed independent associations with New York Heart Association functional class III or IV heart failure symptoms.

The calculation of echocardiography-based LVMW indices is feasible in patients with severe AS. In particular, LV global work index and global constructive work showed independent associations with heart failure symptoms and may provide additional information on myocardial remodeling and function in patients with severe AS.