Thorac Cardiovasc Surg 2016; 64 - OP112
DOI: 10.1055/s-0036-1571563

Impact of Gradient and Flow on Perioperative Renal Function after Transcatheter Aortic Valve Implantation

M. Kofler 1, H. Baumbach 2, S. J. Reinstadler 3, S. Ahad 2, S. Hill 4, L. Stastny 5, G. Feuchtner 6, S. Müller 3, L. Müller 1, T. Bartel 3, W. M. Franz 3, M. Grimm 1, N. Bonaros 1
  • 1Medical University of Innsbruck, Cardiac Surgery, Innsbruck, Austria
  • 2Robert Bosch Krankenhaus, Cardiac Surgery, Stuttgart, Germany
  • 3Medical University of Innsbruck, Cardiology, Innsbruck, Austria
  • 4Robert Bosch Krankenhaus, Cardiology, Stuttgart, Germany
  • 5Medical University of Innsbruck, Innsbruck, Austria
  • 6Medical University of Innsbruck, Radiology, Innsbruck, Austria

Objective: Postoperative acute kidney injury (AKI) was shown to be associated with an increased mortality after transcatheter aortic valve implantation (TAVI). In this analysis, we aimed to investigate the impact of preoperative gradient and flow on kidney function after TAVI.

Methods: From 2008 to 2015, a total of 717 consecutive patients underwent TAVI for severe aortic stenosis (AS) in this two center study.

We divided our study population into 4 groups and compared patients with high gradient AS (n = 520, mean gradient ≥40mmHG; HG-AS) to those with low gradient AS (n = 197, mean gradient < 40mmHG; LG-AS) and patients with high flow AS (n = 330, stroke volume index >35ml/m2, HF-AS) to those with low flow AS (n = 314, stroke volume index < 35ml/m2, LF-AS) Overall mean age was 81.7 ( ± 5.6) years, and overall mean STS-score was 6.9 ( ± 5.5) %. VARC II- Criteria were used as clinical endpoint.

Results: Perioperative mortality did not differ between patients with low versus high gradient AS (LG-AS 10.0% versus HG-AS 7.9%, p = 0.368). Device success, early safety and clinical efficacy were similar between the groups (all p > 0.05). AKI ≥ stage 2 was detected significantly more often in the low gradient group (LG-AS 16.8% versus HG-AS 10.8%, p = 0.032).

With regard to the impact of flow, no difference was seen on mortality between patients with low versus high flow AS p = 0.322). Device success, early safety and clinical efficacy were also similar between the two groups (all p > 0.05). The incidence of AKI ≥ stage 2 was higher in the low flow group (LF-AS 18.2%), as compared with the high flow group (HF-AS 7.6%, p< 0.001). Time-related valve safety was not different between all four groups.

Conclusion: Although we were able to show very good results regarding clinical outcome we identified low flow and low gradient to have an impact on renal function in patients undergoing TAVI.