MELD exceptions for portopulmonary hypertension: current policy and future implementation

Area of Science:

• Transplantation immunology
• Cardiology
• Hepatology

Background:

• Liver transplant candidates with portopulmonary hypertension (POPH) have been eligible for Model for End-Stage Liver Disease (MELD) exception points since 2006.
• The effectiveness and implementation of this POPH exception policy remain unevaluated.

Purpose of the Study:

• To evaluate the outcomes of liver transplant waitlist candidates with approved POPH MELD exceptions.
• To assess the adherence to formal criteria and hemodynamic parameters for POPH MELD exceptions.

Main Methods:

• Utilized data from the Organ Procurement and Transplantation Network (OPTN) from 2006 to 2012.
• Compared outcomes of patients with approved POPH MELD exceptions to non-exception waitlist candidates.
• Employed multivariable multistate survival models to analyze mortality risk.

Main Results:

• 155 patients received POPH MELD exceptions, but only 47.1% met formal OPTN criteria.
• Over one-third lacked consistent hemodynamic criteria or had missing data, yet 80% received transplants.
• POPH MELD exception recipients faced increased mortality risk compared to non-exception candidates (HR: 2.46 with criteria; HR: 1.60 without).

Conclusions:

• The current POPH MELD exception policy and its awarding process require reconsideration by OPTN/UNOS.
• Inconsistent application of criteria and potential biases in the exception point system may impact patient outcomes.