Safety of Iodinated Contrast in Liver Transplant Candidates With Decreased Renal Function Undergoing Coronary CT Angiography

Diagnostic Performance and Iodinated Contrast Safety of Coronary Computed Tomography Angiography in Liver Transplant Candidates With Decreased Renal Function

This study evaluates the safety of iodinated contrast medium administered to liver transplant candidates with decreased renal function undergoing coronary CT angiography. Incidence of post-contrast acute kidney injury in liver transplant candidates with decreased renal function and normal renal function will be compared.

Low osmolar non-ionic contrast medium (LOCM) is routinely used for contrast-enhanced computed tomography (CT) including coronary computed tomography angiography (CCTA).

This study evaluates the effect of LOCM on liver transplant candidates with normal and decreased renal function undergoing CCTA. Incidence of post-contrast acute kidney injury (PC-AKI) will be compared between the two groups before and after contrast medium exposure.

LOCM is a potential cause of PC-AKI, especially in vulnerable population with decreased renal function. According to the American College of Radiology (ACR) manual on contrast media, however, many published studies on PC-AKI in the past have been heavily contaminated by bias and conflation. More recent studies do not confirm a high risk of contrast induced nephropathy.

End stage liver disease patients with normal renal function do not seem to be at a higher risk of developing PC-AKI. Only limited data reporting a low incidence of PC-AKI after contrast-enhanced CT in patients with liver cirrhosis and concomitant decreased renal function exists. Proof of low PC-AKI in this specific population would allow to redirect patients from invasive catheterization to CCTA as their cardiac clearance before transplantation. This study will prospectively investigate the incidence of PC-AKI in this specific at-risk population.

Inclusion Criteria:

- Liver transplant candidate, age > 21 referred for coronary CT angiography, medium-risk patient for coronary artery disease

Exclusion Criteria:

• Liver transplant candidates who are at low-risk for coronary artery disease and therefore do not need coronary CT angiography or invasive catheterization
• Liver transplant candidates who are at high-risk for coronary artery disease and are referred directly to invasive catheterization
• Candidates with chronic kidney disease stage 4, with eGFR <30 ml/min/1.73m2
• Known or suspected allergy to standard iodine contrast medium