ABC | Volume 113, Nº6, December 2019

Original Article Calça et al. Aortic valve repair and kidney function Arq Bras Cardiol. 2019; 113(6):1104-1111 Table 1 – Baseline characteristics All patients (n = 233) Group 1 (n = 100) Group 2 (n = 101) Group 3 (n = 32) P-value Females, n (%) 132 (56.7) 49 (49) 66 (64.7) 17 (54.8) 0.078 Age (years, mean ± SD) 81.8 ± 7.5 80.0 ± 9.2 83.5 ± 5.6 81.7 ± 4.9 0.003 Diabetes, n (%) 71 (30.5) 27 (27) 31 (30.4) 13 (41.9) 0.30 Coronary artery disease, n (%) 94 (40.3) 36 (36) 45 (44.1) 13 (41.9) 0.46 Peripheral vascular disease, n (%) 52 (22.3) 18 (18) 28 (27.5) 6 (19.4) 0.23 Hypertension, n (%) 162 (69.5) 73 (73) 70 (68.6) 19 (61.3) 0.46 Chronic heart disease, n (%) 82 (35.2) 30 (30) 37 (36.7) 15 (48.4) 0.16 Obesity, n (%) 29 (17.2) 14 (14) 14 (13.7) 1 (5.9) 0.43 sCreat 1.2 ± 0.49 0.85 ± 0.16 1.26 ± 0.26 2.13 ± 0.45 < 0.001 eGFR 55.2 ± 19.9 74.6 ± 9.5 45.3 ± 8.4 25.0 ± 4.5 < 0.001 Iodine contrast volume (mL) 144.8 ± 82.8 152.7 ± 101.2 139.9 ± 65.1 134.5 ± 64.7 0.434 Dead n (%) 62 (26.6) 29 (29) 21 (20.6) 12 (38.7) 0.11 sCreat: serum creatinine; eGFR: estimated glomerular filtration rate. The mean volume of iodine contrast was 144.8 ± 82.8 mL, with no differences in the three groups (p = 0.434). Out of all patients, 54.5% received Iomeron®, and 45.5% received Visipaque®. In Group 1 , 65.0% of patients received Iomeron®, and 35.0% received Visipaque® (p = 0.004). In Group 2 and Group 3 patients, there was no difference between the iodine contrast used (p = 0.092 and p = 0.151, respectively) (Table 2). The TAVI procedure had a significant effect on kidney function in the three groups . Sphericity was assumed by Mauchly’s test in Group 1 and Group 3 [ χ 2 (2) = 4.34, p = 0.144, χ 2 (2) = 0.54, p = 0.763[. Greenhouse-Geisser correction was used in Group 3 [ χ 2 (2)=6.93, p = 0.031]. Patients from Group 1 showed a progressive decrease in eGFR after TAVI [F (2-118) = 12.77, p < 0.001], reaching a value of 63.4 ± 19.2 mL/min/1.73 m 2 one year after the procedure (Table 3 and Table 4). The decline in kidney function was more significant in the first month after the TAVI procedure (Table 4 and Figure 2-A). Patients from Group 2 presented an increase in eGFR [F (2‑94) = 6.25, p = 0.003] one month and one year after TAVI (Table 5). The difference between eGFRmeans was higher one month after the procedure (Figure 2-B) . Group 3 had the same results, that is, the mean eGFR increased over time after the procedure [F (2-32) = 5.91, p = 0.014], and the improvement in kidney function was greater in the first month (Table 6 and Figure 2-C). A multivariate analysis adjusted for gender, age, and comorbidities did not change the variations in eGFR across the three groups. In a logistic regression model for patients whose kidney function worsened after one month and one year, the contrast administered was a predictor of worsening. Administration of Iomeron ® was a predictor of worsening in renal function after one year (HR 4.397, 95%CI 1.584–7.286, p = 0.002). On the other hand, the volume administrated was not a predictor of worsening in eGFR after one month (HR 0.997, 95%CI 0.994–1.001, p = 0.125) and one year (HR 0.999, 95%CI 0.995–1.002, p = 0.476). The incidence of patients needing to initiate dialysis twelve months after the TAVI procedure was 2.4% (five patients). Before TAVI, one of these patients was in Group 1; two were in Group 2; and two were in Group 3. We did not find a statistically significant difference in mortality among the three groups (p=0.11). All of these patients had chronic heart failure, and four died. Discussion This analysis contains data from patients who underwent TAVI in a single center from November 2008 to May 2016. The present results suggest that kidney function might improve in patients with CKD G3-5 after the correction of aortic stenosis. However, in patients with no CKD or with CKD G1-2 (eGFR ≥ 60 mL/min/1.73 m 2 ), the eGFR decreased during the follow-up. This study also shows a low incidence of new dialysis – 2.4% (five patients). Several studies address the prognosis and factors that influence mortality and other poor outcomes in patients with CKD undergoing aortic valve replacement, but little is known about the effect of the treatment of aortic valve disease on kidney function. This study reveals that our patients with CKD G3-5 (eGFR < 60 mL/min/1.73 m 2 ) had an improvement in kidney function one month after aortic valve replacement, maintaining the improvement after one year of follow-up. Other studies have also indicated this potential reversibility of CKD, both early and after one year of follow-up. 2,14–16 A studywith 69 patients froma single center in Brazil 14 showed an acute kidney recovery after the TAVI procedure. After one year of follow-up, all patients who had an acute recovery remained with improved levels of sCreat. This work also suggests that kidney recovery is more frequent in patients who hadmore severe renal 1106