Abstract
BACKGROUND Post-procedural risk stratification based on renal function after trans aortic valve implantation (TAVI) was assessed by means of a modified age, creatinine, and ejection fraction (ACEF) score using the lowest glomerular filtration rate (GFR), obtained within 1 week after valve implantation. We refer to the score as ACEF-7 score. METHODS The Zurich- and Cardiocentro Ticino TAVI-Cohorts comprised of 424, and 137 patients, who were not on hemodialysis and had already survived the first post-procedural week. Zurich patients were stratified into tertiles of ACEF-7 score (ACEF-7 ≤ 2.45 (n = 138), ACEF-7 2.46-4.38 (n = 142), and ACEF-7 ≥ 4.39 (n = 144) and compared for survival using KM curves. Euroscore II, Society of Thoracic Surgeons (STS), and ACEF were also calculated at baseline in all patients and assessed for prognostic significance in predicting the primary outcome of 1-year all-cause mortality using univariate and multivariate Cox regression models. Results were then confirmed in the Cardiocentro cohort. RESULTS Six months (18.1% vs. 6.3% vs. 2.9% P < 0.001) and 1-year all-cause mortality (24.3% vs. 12.7% % vs. 5.8%, P < 0.001), as well as the composite of death or rehospitalization (35% vs. 20% vs. 11% P < 0.001) occurred significantly more frequently in the ACEF-7 compared to the other groups. Both Euroscore II and STS score were not predictors of mortality in our cohort. In a multivariate Cox regression model corrected for gender, Acute Kidney Injury, and baseline ACEF score, the ACEF-7 score was an independent predictor of 1-year all-cause mortality as a per point increment HR 1.512 [95% CI 1.227-1.862, P < 0.001] and as ACEF-7 (≥4.39); HR 5.541 [1.694-18.120]). In addition, the ACEF-7 tertiles showed a significant (P = 0.02) net reclassification improvement of 16% when compared to baseline tertiles of ACEF score, when assessing 1-year all-cause mortality. CONCLUSION Post-procedural risk stratification using the simple ACEF-7 score significantly better predicted long-term outcome than commonly used risk-scores. Practical implications could include contrast sparing and renal protection in high-risk patients, emphasizing the importance of preventative measures.