Summary & Overview
CPT 0087U: Molecular Microscope MMDx—Heart mRNA Transplant Assay
CPT code 0087U identifies a Proprietary Laboratory Analyses (PLA) test — the Molecular Microscope® MMDx—Heart assay from Kashi Clinical Laboratories — that measures mRNA levels in heart transplant biopsy tissue and compares results to a reference library to identify causes of graft dysfunction. This PLA code matters nationally because it denotes a single-manufacturer, high-complexity molecular diagnostic service used in transplant management and can affect coverage, coding consistency, and lab reimbursement decisions across insurers.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical purpose and lab setting for the assay, a summary of which payers are included in the review, and an outline of the topics typically addressed in payer and policy assessments for PLA tests. These topics include payer coverage patterns, billing and coding practice considerations for proprietary molecular tests, and clinical context for transplant surveillance and diagnostic differentiation.
The publication presents benchmarks and policy-relevant items for national audiences, highlights payer-specific coverage themes where available, and provides clinical context to inform coding and billing workflows related to proprietary transplant diagnostic assays. Data not available in the input will be noted where applicable.
Billing Code Overview
CPT code 0087U is a Proprietary Laboratory Analyses (PLA) code for the Molecular Microscope® MMDx—Heart test provided by Kashi Clinical Laboratories. The test measures mRNA expression levels in transplanted heart biopsy tissue and compares results to a reference library to determine the likely reason for transplant organ dysfunction or failure.
Service Type: Laboratory molecular diagnostic test (proprietary gene-expression assay)
Typical Site of Service: Clinical laboratory or reference laboratory processing transplant biopsy specimens
Clinical & Coding Specifications
Clinical Context
A 56-year-old patient with a history of orthotopic heart transplantation presents with progressive graft dysfunction identified by rising filling pressures on catheterization, new or worsening heart failure symptoms, or unexplained decline in left ventricular function on echocardiography. Endomyocardial biopsy is performed via right internal jugular venous access in the cardiac catheterization lab or hybrid procedure suite. Fresh-frozen or appropriately preserved biopsy tissue is sent to Kashi Clinical Laboratories for the Molecular Microscope® MMDx—Heart assay, reported with PLA code 0087U. The test measures mRNA expression in the biopsy specimen and compares it to a reference library to help distinguish causes of graft dysfunction such as acute cellular rejection, antibody-mediated rejection, or nonimmune injury. Typical workflow steps: obtain biopsy samples during the catheterization procedure, place specimens in the laboratory-specified transport medium, complete accompanying requisition with clinical history and ICD-10 diagnoses, ship specimens under validated conditions to the performing laboratory, and receive a molecular diagnostic report that informs the transplant team’s differential diagnosis and management planning.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | Unspecified modifier | Rarely used; only if a payer requires a placeholder and no other modifier applies. |
| Primary procedure | When is the principal test billed for the encounter.