The Impact of Surgical and Trans-Catheter Aortic Valve Replacement on Endothelial Function: New Markers Ahead

Aortic stenosis is the most common valvular disease in the elderly. Treatments include both surgical conventional aortic valve replacement via median sternotomy with the aid of cardiopulmonary bypass and less invasive percutaneous trans-catheter techniques. The latter approach is indicated in high-risk patients. Nevertheless evidences are suggesting that the percutaneous approach may be equally beneficial for intermediate risk patients. The superiority of one technique over the other is judged on standard outcomes such as mortality, morbidity, survival etc. However novel markers of hemodynamic performance are emerging, and among them endothelial dysfunction is gaining popularity. Aortic stenosis, because of turbulent flow, is associated with impairment of endothelial reactivity, and resolving the aortic stenosis might results in a better endothelial function. Whether surgical or trans-catheter replacement is associated with better early and late endothelial performance is currently under investigation. Moreover, conventional surgery is performed with the aid of cardiopulmonary bypass and that may have a negative impact on the endothelial function in the early phase. On the other side, the trans-catheter approach may results in endothelial stress due to the ‘travelling phase’ of the prosthesis inside the aortic vessels. The endothelial dysfunction might be assessed either macroscopically (e.g. evaluating the pulsatility of brachial artery after brief episode of ischemia reperfusion) or microscopically (e.g. circulating endothelial micro-particles). This chapter reviews the current evidences of endothelial performance of both the procedures, and highlights the importance of endothelial function as a marker of severity of the aortic stenosis but also as an indicator of early and late procedural outcomes.