In asymptomatic aortic stenosis, basal longitudinal strain was independently associated with maximal exercise capacity measured by peak VO2 (β = 0.50; P=0.03).
Observational (n=44)
Which echocardiographic parameters of left ventricular systolic function predict maximal exercise capacity in asymptomatic aortic stenosis?
In asymptomatic patients with moderate to severe aortic stenosis, impaired basal left ventricular longitudinal strain is independently associated with reduced maximal exercise capacity.
Effect estimate: β = 0.50
p-value: p=0.03
AIMS: The objective assessment of maximal exercise capacity (MEC) using peak oxygen consumption (VO2) measurement may be helpful in the management of asymptomatic aortic stenosis (AS) patients. However, the relationship between left ventricular (LV) function and MEC has been relatively unexplored. We aimed to identify which echocardiographic parameters of LV systolic function can predict MEC in asymptomatic AS. METHODS AND RESULTS: Asymptomatic patients with moderate to severe AS (n = 44, aortic valve area 50%) were prospectively referred for resting echocardiography and cardiopulmonary exercise test. LV longitudinal strain (LS) of each myocardial segment was measured by speckle tracking echocardiography (STE) from the apical (aLS) 4-, 2-, and 3-chamber views. An average value of the LS of the analysable segments was provided for each myocardial region: basal (bLS), mid (mLS), and aLS. LV circumferential and radial strains were measured from short-axis views. Peak VO2 was 20.1 ± 5.8 mL/kg/min (median 20.7 mL/kg/min; range 7.2-32.3 mL/kg/min). According to the median of peak VO2, patients with reduced MEC were significantly older (P < 0.001) and more frequently females (P = 0.05). There were significant correlations between peak VO2 and age (r = -0.44), LV end-diastolic volume (r = 0.35), LV stroke volume (r = 0.37), indexed stroke volume (r = 0.32), and E/e' ratio (r = -0.37, all P < 0.04). Parameters of AS severity and LVEF did not correlate with peak VO2 (P = NS for all). Among LV deformation parameters, bLS and mLS were significantly associated with peakVO2 (r = 0.43, P = 0.005, and r = 0.32, P = 0.04, respectively). With multivariable analysis, female gender (β = 4.9; P = 0.008) and bLS (β = 0.50; P = 0.03) were the only independent determinants (r(2) = 0.423) of peak VO2. CONCLUSION: In asymptomatic AS, impaired LV myocardial longitudinal function determines reduced MEC. Basal LS was the only parameter of LV regional function independently associated with MEC.
Dulgheru et al. (Tue,) conducted a observational in Asymptomatic moderate to severe aortic stenosis (n=44). Echocardiographic parameters of LV systolic function (basal longitudinal strain) was evaluated on Maximal exercise capacity (peak VO2) (β = 0.50, p=0.03). In asymptomatic aortic stenosis, basal longitudinal strain was independently associated with maximal exercise capacity measured by peak VO2 (β = 0.50; P=0.03).