Intermediate CD14++CD16+ monocytes decline after transcatheter aortic valve replacement and correlate with functional capacity and left ventricular systolic function

Background Transcatheter aortic valve replacement (TAVR) is the method of choice for patients with severe aortic valve stenosis, who are ineligible or at high risk for surgery. Though TAVR leads to a significant reduction in mortality, a notable amount of patients are re-hospitalized early after TAVR. Parameters or biomarkers predicting outcome are therefore needed to identify patients who benefit most. Specific monocyte subsets have been associated with cardiovascular diseases and were shown to possess prognostic value. Methods Peripheral blood was drawn before and after transfemoral TAVR with the self-expanding CoreValve, Boston Lotus or the balloon-expanding Edwards Sapien prosthesis. Classical (CD14(++)CD16(-)), intermediate (CD14(++)CD16(+)) and non-classical (CD14(+)CD16(++)) monocyte subsets were determined by flow cytometry. Transthoracic echocardiography was performed before, early after as well as 3 months after the TAVR procedure. Results No significant differences in the absolute monocyte counts were found after TAVR. A significant decline in the intermediate monocyte population was though observed early after TAVR (pre 4.01 +/-.38%, post 2.803 +/- 0.34%, p <= 0.05). Creatinine levels stayed stable after TAVR procedure and intermediate monocytes were associated with worse renal function. Monocyte decline was not related to changes in CRP-, noradrenaline, cortisol or aldosterone-levels. The amount of intermediate monocytes correlated with worse cardiac function and predicted the possibility to reach an improvement in NYHA functional class at 3 months after TAVR. Conclusions A significant decline of intermediate monocytes occurs shortly after TAVR. High levels of intermediate monocytes were associated with worse cardiac function and predicted poor functional capacity, hinting at a possible prognostic value.