P291 Additional value of myocardial work in detecting subclinical systolic dysfunction in patients with bicuspid aortic valve and left ventricular hypertrophy
Authors: Canonico M E , Santoro C , Prastaro M , Sorrentino R , Luciano F , Lembo M , Esposito R , Galderisi M 
Published: January 2020

Abstract

Background
An impairment of speckle tracking derived left ventricular (LV) global longitudinal strain (GLS) has been observed in patients with bicuspid aortic valve (BAV) and referred to abnormalities of aortic elasticity properties. The impact of LV mass on myocardial deformation has still not been investigated. This issue can be now better addressed by myocardial work software, which incorporates both deformation and hemodynamic load in the analysis.

Aim of the study
To analyse the impact of both deformation and strain derived myocardial work in BAV patients with and without LV hypertrophy (LVH).

Methods
Sixty-five patients with BAV underwent a comprehensive echo exam, including speckle tracking derived calculation of GLS (in absolute value). Parameters of myocardial work such as global work index (GWI), global constructive work (GCW) global wasted work (GWW) and global work efficiency (GWE) were measured according to standardized procedures. Patients with reduced LV ejection fraction and with more than mild aortic stenosis and/or regurgitation were excluded. Other exclusion criteria included coronary artery disease, concomitant valvular heart disease, heart failure, primary cardiomyopathies, permanent and/or persistent atrial fibrillation and inadequate echo images. BAV patients were divided according to presence of LVH: 10 with LVH (LV mass index &gt;47 g/m^2.7 in women and &gt;50 g/m^2.7 in men) and 55 without LVH.

Results
The two groups were comparable for sex, age and heart rate whereas systolic blood pressure (p = 0.006) and pulse pressure (p = 0.002) were higher in patients with LVH, who also had higher relative diastolic wall thickness (p &lt; 0.02). No significant difference in ejection fraction (p = 0.56), transmitral E/A ratio (p = 0.504) and E/e" (p = 0.311) was found between the two groups. GLS (19.1 ± 2.5 in LVH group and. 20.0 ± 2.4% in patients without LVH, p = 0.290), GWI (p = 0.356) and GCW (p = 0.396) did not differ significantly whereas GWW was higher (119.5 ± 72.9 vs. 72.3 ± 38.7 mmHg%, p = 0.003) and GWE lower (94.4 ± 3.0 vs. 92.2 ± 1.6%, p = 0.007) in BAV patients with LVH (Figure). In the pooled population, LV mass index was related with GWW (r = 0.26, p = 0.03) and GWE (r=-0.30, p &lt; 0.01) but not with GLS (r=-0.22, p = 0.08). The relation between GWE and LV mass index remained significant even after adjusting for pulse pressure (partial r=-0.28, p &lt; 0.02).

Conclusion
In patients with BAV, LVH plays a detrimental effect on LV systolic function which cannot be identified by ejection fraction and GLS assessment but is unmasked by the application of myocardial work. In presence of LVH, the wasted work of BAV patients is increased and myocardial efficiency is substantially reduced, it being negatively related to LV mass even after adjusting for a raw index of aortic stiffness such as pulse pressure.
Abstract P291 Figure. GLS, GWW and GWE according to LVH