The effect of surgical aortic valve replacement on aortic stiffness and the prognostic role of aortic stiffness on surgical success

Abstract

Purpose/Background/ObjectivesAortic stiffness and hemodynamics are established biomarkers for cardiovascular events. Surgical aortic valve replacement (SAVR) remains the first choice of treatment in most patients with aortic stenosis. We investigated the effect of SAVR on aortic stiffness and the role of arterial biomarkers in predicting the echocardiographic respons.MethodsWe included thirty-three patients (mean age 71 ± 8 years, 58% males) with moderate to severe aortic stenosis undergoing SAVR. In measurements prior and acutely after the surgery, carotid-femoral pulse wave velocity (cfPWV) and brachial-ankle pulse wave velocity (baPWV) and aortic hemodynamics (aortic augmentation index corrected for heart rate [AIx@75]) were used as indicators of arterial stiffness. Echocardiography, mean and peak pressure gradient of the aortic valve was measured and their differences post and pre-surgery were calculated (i.e. ΔMeanGradient = MeanGradient post-surgery—MeanGradient pre-surgery).ResultsThere was a statistically significant increase on measurements of aortic stiffness (7.5 ± 1.4 vs 8.2 ±1.9 m/s for cfPWV, p = 0.033) and a decrease in wave reflections (28 ± 13% vs 21 ±11% for AIx@75, p = 0.015). We also observed a negative association of baseline cfPWV with baseline mean and peak gradient of aortic stenosis (r = −0.598 and r = −0.614 with p = 0.002 and p = 0.001, respectively), independently of age, gender and systolic blood pressure. Baseline cfPWV was associated with ΔMeanGradient and ΔPeakGradient (r = 0.609 and r = 0.533 with p = 0.002 and p = 0.009, respectively). (Figure)ConclusionsOur study shows that post-operative aortic stiffness increases while there is an improvement of wave reflections. Furthermore, increased aortic stiffness prior to surgery predicts smaller benefit in decreasing transvalvular pressure gradient as assessed echocardiographi-cally, implying that low aortic stiffness prior to surgery could lead to better outcome.