Evaluating zero contrast transcatheter aortic valve implantation (TAVI) for patients with renal impairment

Abstract Background Transcatheter Aortic Valve Implantation (TAVI) is a well-established treatment for severe aortic stenosis (AS) but poses risks for chronic kidney disease (CKD) patients due to contrast-induced nephropathy (CIN). Zero-contrast TAVI offers a promising alternative, though evidence on its safety and effectiveness is limited. Purpose We aim to evaluate the safety and effectiveness of zero-contrast TAVI compared to standard TAVI in patients with AS and CKD. Methods We followed the Cochrane Handbook and PRISMA guidelines, searching databases until September 2024. We conducted the meta-analysis using the ‘metafor’ package with a random-effects model, calculating mean differences (MDs) and risk ratios (RRs) along with their corresponding 95% confidence intervals (CIs). Results We included 1505 patients from six papers. The single-arm meta-analysis of zero-contrast TAVI showed a significant implantation success rate (proportion = 0.97; 95% CI: [0.95, 0.99]; p < 0.01). Double-arm analysis revealed no significant difference in implantation success between both groups (RR = 1.02; 95% CI: [0.97, 1.08]; p = 0.34). The postoperative mean transvalvular gradient was comparable (MD = 0.19 mmHg; 95% CI: [−0.99, 1.39]; p = 0.75). The initial pooled analysis found no significant difference in in-hospital AKI (RR = 0.66, 95% CI: 0.20–2.17), though this was confounded by significant heterogeneity (I2 = 71.26%). Sensitivity analysis resolved this heterogeneity and revealed a significant reduction in AKI with Zero-contrast TAVI (RR = 0.47, 95% CI: [0.24, 0.92]; p = 0.03). Post-procedural permanent pacemaker (PPM) implantation risk was higher in the zero-contrast group, while Stroke rates were comparable. Conclusion Zero-contrast TAVI offers comparable success to contrast-based approaches and potential renal benefits but carries a higher risk of PPM implantation.