Objective: Contrast-induced nephropathy (CIN) is the third most common cause of acute renal failure and is associated with increased morbidity and in-hospital mortality. Some recent studies identified female sex as a risk factor of CIN. The aim of this study was to determine the relative impact of female sex on the development and clinical outcome of CIN in patients with preexisting renal impairment after transapical transcatheter aortic valve implantation (TAVI).
Methods: From February 2008 to February 2011, a total of 55 TAVI patients [82.4 (6.5) years] with preprocedural serum creatinine level of greater than 1.1 mg/dL were retrospectively investigated. The incidence of postprocedural CIN, lengths of intensive care unit and hospital stay, and short-term mortality among men and women were compared. Contrast-induced nephropathy was defined as a creatinine increase of greater than 0.5 mg/dL or greater than 25% from baseline within 3 days after contrast medium (CM) exposure.
Results: The women had significantly lower body surface area [1.8 (0.18) vs 1.95 (0.17) m2; P = 0.002), lower hemoglobin levels [11.5 (1.3) vs 12.7 (1.6) g/dL, P < 0.001], and lower estimated glomerular filtration rate [34.2 (9.7) vs 49.4 (12.3) mL/min per 1.73 m2, P = 0.002]. The amount of CM given was significantly higher in the women relative to body surface area [67.3 (42.5) vs 48.3 (16.6) mL/m2, P = 0.043]. The women received a higher number of blood cell transfusion units [4.4 (3.4) vs 2.1 (2.7) U, P = 0.006]. The frequency of CIN within 72 hours after CM exposure was significantly higher in the women (62.1% vs 26.9%, P = 0.009). A total of 31% of the women (n = 9) versus 7.7% of the men (n = 2) needed hemodialysis (P = 0.031). Analysis of the postoperative morbidity in terms of length of intensive care unit and hospital stay revealed no significant difference between the two groups. Mortality results reached a significant difference at 60 days, with 31% (n = 9) mortality in the women compared with 7.7% (n = 2) in the men (P = 0.031).
Conclusions: Women with preexisting renal impairment are at higher risk than men for CIN, with resultant higher early mortality after transapical TAVI.