Longitudinal changes in kidney function following heart transplantation: Stanford experience

Area of Science:

• Nephrology
• Cardiology
• Transplantation Medicine

Background:

• Declining kidney function is a common complication after heart transplantation.
• Pre-transplant kidney function significantly impacts post-transplant outcomes.
• Understanding kidney function trajectories is vital for patient management.

Purpose of the Study:

• To quantify changes in kidney function in heart transplant recipients.
• To stratify kidney function changes based on pre-transplant kidney health.
• To assess the long-term risk of severe kidney dysfunction (eGFR <20 mL/min/1.73 m²).

Main Methods:

• Retrospective analysis of 230 adult heart transplant recipients (2008-2014).
• Evaluation of estimated glomerular filtration rate (eGFR) trends up to 5 years post-transplant.
• Stratification into normal/near-normal (eGFR ≥45) and impaired (eGFR <45) pre-transplant kidney function groups.

Main Results:

• The impaired group experienced an initial mean eGFR gain of 9.5 mL/min/1.73 m², while the normal group had a mean decline of 4.9 mL/min/1.73 m².
• Subsequent eGFR decline rates were 2.2 mL/min/1.73 m²/year (impaired) and 2.9 mL/min/1.73 m²/year (normal).
• 10-year risk of eGFR ≤20 mL/min/1.73 m² was 30% in the impaired group vs. 10% in the normal group.

Conclusions:

• Heart transplant recipients with impaired pre-transplant kidney function demonstrate initial recovery but still face higher long-term risks.
• Recipients with normal pre-transplant kidney function experience a gradual decline post-transplant.
• These findings aid in optimizing kidney care strategies for heart transplant recipients.