Impact of arterial stiffness on echocardiographic myocardial work indices in patients with isolated bicuspid aortic valve.

Abstract

Data related to the existence of left ventricular (LV) abnormalities in normal functional bicuspid aortic valve (BAV) disease is scarce. In addition, the impact of afterload and the involved mechanisms are unclear. In this work, we study the relationship between LV function assessed with myocardial work index (MWI) and arterial stiffness in a cohort of normal functioning BAV patients. In this study, we included a total of 38 consecutive patients with isolated BAV and 44 age- and gender-matched control subjects with tricuspid aortic valve. All participants underwent transthoracic echocardiography to assess conventional parameters and global longitudinal strain (GLS). In addition, MWI was measured by the noninvasive LV pressure-strain cycle method. Aortic pulse wave velocity (PWV) and wave reflection were evaluated by applanation tonometry. The mean aortic PWV was significantly higher in BAV patients (6.4 ± 0.80, 7.02 ± 0.1.2, p=.01, respectively). LV-MWI related parameters such as global work efficiency (GWE) (96.261.69 and 97.051.27, p=.02) and global wasted work (GWW) (78.232.1 and 61.824.4, p=.01) were found significantly different between the BAV and control groups. However, global working index and global constructive working were not different between groups (1969 ± 259 and 2014 ± 278, p=.45; 2299 ± 290 and 2359 ± 345, p=.39, respectively). Multivariable ordinary least squares regression analysis revealed that BAV (ß=8.4; 95% CI: 1.5-15.3; p=.04) and PVW (ß=5.6; 95% CI: 0.7-10.5; p=.01) were significant predictors of GWV. GWW is increased and GWE is decreased in patients with BAV compared with controls, and these changes are related to arterial stiffness. The relationship between aortic PWV and GWW may help to explain the exact mechanism of subclinical myocardial dysfunction in patients with isolated BAV.