What is the role of Gadolinium (Gd) based Magnetic Resonance Imaging (MRI) with Technetium (Tc) in heart failure with Acute Kidney Injury (AKI)?

From the Guidelines

Gadolinium-based contrast agents should be used with caution in patients with heart failure complicated by acute kidney injury (AKI), and alternative imaging techniques without contrast should be considered first. The use of intravenous gadolinium-based contrast media (GBCM) in patients with kidney disease, including those with AKI, has been addressed in a consensus statement by the American College of Radiology and the National Kidney Foundation 1. According to this statement, the risk of nephrogenic systemic fibrosis (NSF) or nephrotoxicity following administration of a standard dose of a group II GBCM is extremely low. However, the harms of delaying or withholding group II GBCM for a clinically indicated MRI in a patient with AKI or estimated glomerular filtration rate less than 30 mL/min per 1.73 m2 may outweigh the risk of NSF, regardless of dialysis status.

When considering the use of GBCM in patients with heart failure and AKI, the following factors should be taken into account:

• The potential benefits of diagnostic information from MRI with GBCM must be carefully weighed against the risk of worsening kidney function and potential complications.
• Alternative imaging techniques without contrast, such as non-contrast MRI, echocardiography, or nuclear medicine studies, should be considered first.
• If GBCM must be used, macrocyclic gadolinium agents (such as gadoterate meglumine, gadobutrol, or gadoteridol) at the lowest possible dose should be used, as they have a lower risk of NSF.
• Ensure adequate hydration before and after the procedure, temporarily discontinue nephrotoxic medications if possible, and monitor renal function closely.

The role of Technetium (Tc) in this context is not directly addressed in the provided evidence, but it is essential to consider the overall clinical context and the potential benefits and risks of using Tc in conjunction with GBCM. The primary concern with gadolinium in AKI stems from impaired renal clearance, which increases exposure time and risk of NSF, a rare but serious condition causing skin thickening, joint contractures, and potential internal organ damage 1. Heart failure patients with AKI are particularly vulnerable due to their already compromised renal perfusion and hemodynamic instability.

From the Research

Role of Gadolinium-Based MRI in Heart Failure with Acute Kidney Injury

• The use of gadolinium-based contrast agents (GBCAs) in patients with acute kidney injury (AKI) and chronic kidney disease (CKD) has been controversial due to concerns regarding nephrogenic systemic fibrosis (NSF) 2, 3.
• Studies have shown that GBCAs can induce nephrotoxicity in patients with underlying renal impairment, particularly in those with stage 3 and 4 renal failure 4, 5, 6.
• The risk of gadolinium-induced nephrotoxicity is higher in patients with certain comorbidities, such as diabetic nephropathy, and in those with lower baseline glomerular filtration rate (GFR) 5.
• However, newer GBCAs have been shown to have a lower risk of NSF, and their use in patients with AKI and CKD may be considered individually, with careful monitoring of renal function 2, 3.

Safety Precautions and Guidelines

• The Canadian Association of Radiologists has issued guidelines for the use of GBCAs in patients with kidney disease, recommending that standard doses of GBCAs can be safely used in patients with mild-to-moderate CKD, but that alternative imaging modalities should be considered in patients with AKI, severe CKD, or on dialysis 2, 3.
• The guidelines also recommend that patients with AKI, severe CKD, or on dialysis who require GBCA-enhanced MRI should receive newer GBCAs with patient consent, citing an exceedingly low risk of developing NSF 2, 3.
• Screening for renal disease is important, but less critical when using macrocyclic and newer linear GBCAs, and monitoring for and reporting of potential cases of NSF in patients with AKI or CKD who have received GBCAs is recommended 2, 3.

Technetium (Tc) Role

• There is no direct evidence in the provided studies regarding the role of Technetium (Tc) in heart failure with Acute Kidney Injury (AKI) in combination with Gadolinium-based MRI.

Key Findings

• GBCAs can induce nephrotoxicity in patients with underlying renal impairment, particularly in those with stage 3 and 4 renal failure 4, 5, 6.
• Newer GBCAs have a lower risk of NSF, and their use in patients with AKI and CKD may be considered individually, with careful monitoring of renal function 2, 3.
• Guidelines recommend careful consideration of GBCA use in patients with AKI, severe CKD, or on dialysis, and alternative imaging modalities should be considered whenever possible 2, 3.