Background: Transcatheter aortic valve replacement (TAVR) in patients with chronic kidney disease (CKD) is challenging due to the high risk of contrast-induced nephropathy (CIN) and acute kidney injury (AKI). AKI dramatically reduces the clinical benefit of TAVR and is one of the strongest predictors of 30-day mortality as well as long-term adverse outcomes after TAVR. The aim of this study was to evaluate a protocol specifically designed to reduce the incidence of contrast-induced nephropathy (CIN) in advanced CKD patients screened for and undergoing TAVR.
Methods: Twelve consecutive patients with severe aortic valve stenosis suffering from at least stage 4 CKD underwent both screening with pre-procedural computed tomography scan (CT scan) and bioprosthetic valve implantation without contrast medium. All the TAVR procedures were performed using the CoreValve Evolut R/PRO transcatheter aortic valve (Medtronic Inc, Minneapolis, MN, USA). The annulus and the optimal implantation projection were identified on the non-contrast medium CT scans with the aid of calcifications as a reference. The implant projection was confirmed immediately before the valve implantation by placing two pigtail catheters alternately inside each sinus of Valsalva (SOV).
Results: We enrolled 12 patients: mean age 83.42 4.50 years, number of male 5 (41.7%), mean STS 10.33±6.16, mean EuroScore II 13.75±9.07, mean serum creatinine 2.01±0.63 mg/dL, mean eGFR 23.00±5.69 mL/min/1.7m2. All TAVR procedures were successful, leading to a drop in transaortic mean gradient (mean gradient 33.5±14.09 mmHg; postoperative mean gradient 6.08±mmHg). No patient had more than a mild paravalvular leak. Only two patients underwent permanent pacemaker implantation due to advanced atrioventricular block (AV block). Mean change in eGFR 48 hours after the procedure was 1.3 mL/min. None of the patients developed AKI, according to Valve Academic Research Consortium-2 (VARC-2) definition.
Conclusions: In patients with advanced CKD, a strategy of "zero contrast" TAVR, preceded by accurate CT scan analysis and procedural planning, appears to be safe and feasible permitting to preserve renal function. The avoidance of contrast medium during preprocedural analysis and TAVR implantation could reduce the incidence of AKI and consequently could improve outcomes in this complex patient cohort.