Renal Function-Based Contrast Threshold Predicts Kidney Injury in Transcatheter Aortic Valve Replacement

Area of Science:

• Cardiology
• Nephrology
• Interventional Radiology

Background:

• Acute kidney injury (AKI) is a known complication of contrast-guided procedures.
• The specific relationship between contrast volume and renal function in transcatheter aortic valve replacement (TAVR) patients requires further elucidation.

Purpose of the Study:

• To investigate the predictive value of contrast volume relative to renal function for AKI in TAVR patients.
• To assess the association between AKI and mortality following TAVR.

Main Methods:

• Utilized data from the Michigan TAVR registry (January 2016 - December 2019).
• Defined AKI using Valve Academic Research Consortium 2 criteria.
• Calculated an optimal integer cut point for the ratio of contrast volume (CV) to estimated glomerular filtration rate (eGFR) as an AKI predictor.

Main Results:

• Out of 7112 TAVR cases, 8.8% developed AKI.
• AKI was significantly associated with increased unadjusted and multivariable-adjusted mortality (HR=4.50).
• Higher CV/eGFR ratios (>2 and >3) and general anesthesia were significant predictors of AKI.

Conclusions:

• The ratio of contrast volume to renal function (CV/eGFR) is a reliable predictor of AKI post-TAVR.
• AKI following TAVR is linked to a substantially higher risk of mortality.
• Implementing CV/eGFR thresholds (>2x and >3x) into procedural planning may serve as a valuable quality improvement measure.