Degenerative changes and immune response after transcatheter aortic valve implantation. Comparison with surgical aortic valve replacement.

Background: Little is known about the valve degeneration process after transcutaneous aortic valve implantations (TAVI) that can have an important impact on patients' long-term prognosis.

Aim: To evaluate degenerative changes of TAVI using computed tomography (CT) compared to findings in patients that underwent surgical aortic valve replacement (SAVR). Subsequently, to compare the level of immune and inflammatory markers in both groups and test their possible role in the valve degeneration process.

Methods And Results: 49 patients after TAVI and 29 patients in the control group after SAVR underwent 2 years of follow-up and 8 patients from the TAVI group and 7 patients after SAVR underwent five years of follow-up. CT was performed in all patients and calcifications on prosthesis cusps in both groups were measured using Agatson calcium score. TAVI patients were older compared to patients who underwent SAVR [82 (62;86) vs. 74 (64;84) years, p<0.001], and had more comorbidities - higher EuroScore I [21.0 (5.0;46.0) vs. 6.15 (2.54;11.17), p<0.001]. TAVI patients had more often concomitant coronary artery disease (69.4% vs. 13.8%, p<0.001) and previous history of cardiac surgery (32.7% vs. 0.0%, p<0.001). Slight calcifications (mean Agatson score 50.76) on prosthetic cusps were found in 2 patients 4-5 years after TAVI and in 1 patient 2 years after SAVR (p=NS). Even though significant differences were found in values of tumor necrosis factor-α and E-selectin before, 1 year, and 2 years after implantation, no significant changes in values of inflammatory markers were observed during follow-up period in both groups of patients. Detailed analysis revealed no significant difference between values of inflammatory markers of patients with and without calcifications present on CT.

Conclusion: Minimal degenerative changes on TAVI prosthesis were observed in mid- and long-term follow-up. Systemic immune response did not differ between patients after TAVI and SAVR.