Predictive Roles of Neutrophil-to-Lymphocyte Ratio and C-Reactive Protein in Patients with Calcific Aortic Valve Disease

The neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) are emerging indirect blood markers to roughly reflect the inflammation level in our body while some pathological changes occurring in aortic valve tissue. Few recent studies demonstrated that NLR is related to calcific aortic valve disease (CAVD). However, the extent of the relationship between them and the impact of CRP on CAVD are not clear. This study aimed to investigate the diagnostic influence and surgical predictive effect of NLR and CRP on CAVD. A total of 278 consecutive patients with CAVD (123 patients with bicuspid aortic valve and others with tricuspid aortic valve) and 108 healthy individuals who were included in the control group were enrolled in the study. The NLR was calculated from the complete blood count, and the CRP was measured from peripheral blood samples. Echocardiography was used to evaluate the severity of aortic stenosis. Intraoperation/postoperation indicators were collected in 166 patients from the total consecutive patients who underwent aortic valve replacement (AVR) alone. Significantly higher NLR was measured in both the BAV group (1.96 +/- 0.78 versus 0.97 +/- 0.15, P < 0.001) and the TAV group (2.51 +/- 2.03 versus 0.97 +/- 0.15, P < 0.001) compared with the control group. Moreover, the NLR level was significantly higher (P < 0.001) and the CRP level was significantly lower (P = 0.007) of the TAV group than that of the BAV group; a significant positive correlation between the NLR and the maximum gradient of aortic valve was detected. Furthermore, there was a moderate correlation between the NLR and the postoperative mechanical ventilation time. Our results indicated that the NLR and CRP were novel and useful predictive factors in patients with CAVD, and these two potential factors have guiding significance for the prediction of different pathological typing (BAV or TAV). Higher NLR level will not extend the cardiopulmonary bypass time (CPB); however, it will prolong the operation time and the postoperative mechanical ventilation time.