Impact of Cardiac Function on Indocyanine Green Clearance in MASLD Evaluation

Overview

This prospective controlled study evaluated the utility of indocyanine green (ICG) clearance as a noninvasive marker of liver function in patients with metabolic dysfunction-associated steatotic liver disease (MASLD) undergoing metabolic and bariatric surgery (MBS). The study demonstrated that ICG clearance is reduced in MASLD patients compared to controls and correlates with histological severity. Incorporating cardiac function parameters improved the correlation between ICG clearance and liver histology.

Background

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a common complication of obesity and a key target for metabolic and bariatric surgery (MBS). Liver biopsy remains the diagnostic gold standard but is limited by invasiveness and cost, prompting the need for reliable noninvasive tests. Indocyanine green (ICG) clearance is widely used to assess liver function dynamically, but its interpretation is influenced by hepatic blood flow and potentially cardiac output. This study investigates whether adjusting ICG clearance for cardiac function enhances its diagnostic accuracy in MASLD.

Data Highlights

Key Findings

• ICG clearance (ICG-PDR and ICG-R15) was significantly reduced in patients with MASLD undergoing MBS compared to control patients with BMI < 30.
• ICG clearance parameters correlated with histological severity of MASLD, including steatosis, inflammation, ballooning, and fibrosis scores.
• Adjusting ICG clearance measurements for cardiac output and cardiac index improved correlation with histological features of MASLD.
• Patients with higher MASLD Activity Scores (≥5) showed more pronounced reductions in ICG clearance.
• Noninvasive cardiac function monitoring using the ClearSight system was feasible and provided valuable data to interpret ICG clearance results.

Clinical Implications

ICG clearance is a promising noninvasive tool for assessing liver function in MASLD patients, but its interpretation should consider cardiac function to improve diagnostic accuracy. Incorporating cardiac output and cardiac index measurements can enhance the clinical utility of ICG clearance in evaluating liver disease severity and guiding management in patients undergoing metabolic and bariatric surgery.

Conclusion

The study supports the use of ICG clearance as a noninvasive marker of liver function in MASLD and highlights the importance of accounting for cardiac function parameters to optimize its diagnostic performance. This approach may reduce reliance on invasive liver biopsy and improve patient care.

References

1. Kleiner et al. 2005 -- Design and validation of a histological scoring system for nonalcoholic fatty liver disease
2. Diagnostic Green GmbH -- Indocyanine Green (ICG) properties and clinical use
3. Pulsion Medical Systems -- LiMON device for ICG clearance measurement
4. Edwards Lifesciences Corporation -- ClearSight system for cardiac function monitoring