Zero-contrast Imaging Guided Transcatheter Aortic Valve Replacement in Patients with Severe Chronic Kidney Disease: A Feasibility and Outcome Study

Abstract

Objective: The clinical utility of transcatheter aortic valve replacement (TAVR) without contrast medium in patients with advanced-stage chronic kidney disease (CKD) remains unexplored. We evaluated the feasibility and clinical utility of zero-contrast TAVR in patients with CKD.

Methods: We retrospectively analyzed patients who underwent TAVR between February 2014 and November 2019. We defined zero-contrast TAVR as TAVR performed without contrast medium under transesophageal echocardiographic (TEE) guidance. In zero-contrast TAVR, annulus sizing and other aortic valve complexes were assessed, and valve positioning during deployment was performed under 3D-TEE guidance. We performed an assessment of the aortic valve by TEE just after inducing anesthesia. The calcification of the aortic valve was assessed by non-contrast computed tomography (CT). The access site was assessed by preprocedural ultrasound and intravascular ultrasound during the procedure. The incidence of acute kidney injury (AKI) and other clinical outcomes were compared between TAVR with contrast and zero-contrast TAVR groups. All definitions of the clinical endpoints used in this study were in accordance with the Valve Academic Research Consortium-3 definitions.

Results: Among the 555 patients included in this study, 34 patients (6.1%) underwent zero-contrast TAVR. Although the incidence of AKI in the zero-contrast TAVR group was numerically higher than that in the contrast TAVR group (11% vs. 4%; P = 0.06), stage 2–4 AKI was not recognized in both groups. There were no significant differences in device success (100% vs. 93%; P = 0.28) and 30-day mortality rates (3% vs. 0.5%; P = 0.11) between patients in the zero-contrast TAVR and TAVR with contrast groups. In the zero-contrast TAVR group, post-estimated glomerular filtration rate (eGFR) showed no difference compared to pre-eGFR (19.9 mL/min/1.73 m² [13.5–22.3] vs. 20.3 mL/min/1.73 m² [14.8–28.4]; P = 0.21). When compared between patients with and without preoperative contrast CT, the incidence of AKI in patients with preprocedural contrast CT was numerically higher than that without contrast CT (27% vs. 4%; P = 0.09). No significant difference in major vascular complications was observed between these groups (0% vs. 4%; P = 1.00).

Conclusion: In patients with CKD, zero-contrast TAVR even without preoperative contrast CT may be feasible in terms of high procedural success rate and low incidence of AKI after TAVR.