Association between time-related changes in routine blood morphological parameters and renal function after transcatheter aortic valve implantation – a preliminary study

Introduction
Transcatheter aortic valve implantation (TAVI) although minimally invasive is still accompanied by changes in blood morphological parameters, some of them linked to unfavorable outcomes.
Aim: To find any association between changes in blood morphology reflecting an inflammatory response and acute kidney injury (AKI).

Material and methods
This study involved 176 consecutive transfemoral TAVI patients with a mean age of 78.4 ±7.0 years. Serum creatinine concentration (CREA) and blood morphology were analyzed in the blood samples taken before the procedure, then approximately 1, 24, 48 and 72 hours after the procedure, and lastly at the time of discharge. Post-procedural maximal or minimal values (max/min) and max/min-to-bs ratio of the laboratory parameters were also calculated.

Results
Leucocyte (WBC) and neutrophil (NEUT) counts increased significantly after the procedure whereas lymphocyte (LYMPH) counts declined markedly, reaching the highest or lowest values 24 hours after the procedure. A significant increase in neutrophil-to-lymphocyte ratio (NLR) was observed. Platelet count (PLT) dropped to a minimum at 72 hours after TAVI but at discharge did not return to the admission level. TAVI was associated with a marked increase in CREA with a peak at 48 hours after the procedure (135.7 ±75.9 µM/l). Patients with AKI (n = 65; 36.9%) presented more pronounced variations in relative changes in counts of all blood morphological parameters. A positive moderate (r = 0.412) correlation between maximal NLR and relative CREA changes was noted.

Conclusions
TAVI is associated with significant changes in blood morphological parameters that reflect an inflammatory response. They are more pronounced among subjects with post-procedural AKI.