CPT 0055U: myTAIHEART™ PCR Test for Heart Transplant Rejection

CPT code 0055U is a Proprietary Laboratory Analyses (PLA) code that identifies the myTAIHEART™ laboratory test by TAI Diagnostics, Inc., a PCR-based molecular assay used alongside clinical assessment to evaluate a heart transplant recipient’s risk of rejecting a donor heart. As a PLA code, 0055U applies specifically to this single manufacturer’s test, supporting clarity in billing and tracking of this proprietary diagnostic.

Nationally, the code matters because molecular assays for transplant rejection influence clinical decision-making, utilization of immunosuppression, and downstream resource use. Payors commonly discussing coverage and payment for such assays include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. These payors shape access through coverage policies, prior authorization requirements, and coding guidance.

Readers will learn how 0055U is defined clinically and operationally, which payors are relevant for national coverage discussions, and what to expect in terms of the test’s role in transplant care pathways. The publication provides benchmarks and policy context where available, explains typical service settings, and outlines the clinical intent and application of the assay. Data not available in the input will be noted as such in corresponding sections.

Billing Code Overview

CPT code 0055U is a Proprietary Laboratory Analyses (PLA) code for the myTAIHEART™ laboratory test developed by TAI Diagnostics, Inc. The test uses PCR technology in conjunction with standard clinical assessment to help determine a heart transplant recipient’s likelihood of rejecting a donor heart.

Service Type: Proprietary laboratory molecular diagnostic test (PCR-based) for heart transplant rejection assessment

Typical Site of Service: Clinical laboratory or hospital outpatient laboratory

Clinical Context

A 56-year-old heart transplant recipient presents for routine post-transplant surveillance. The patient is clinically stable but requires laboratory monitoring to detect early allograft rejection. The transplant cardiology team orders the 0055U myTAIHEART™ PCR-based assay performed by TAI Diagnostics, Inc., to assess the molecular signature associated with rejection risk. A peripheral whole-blood sample is collected in the outpatient transplant clinic or hospital laboratory, labeled with the patient and test identifiers, and shipped to the performing laboratory per the manufacturer's instructions. Results are returned to the transplant cardiologist and incorporated with clinical assessment, echocardiography, endomyocardial biopsy results (if available), immunosuppressive drug levels, and other laboratory data to inform surveillance and management decisions. Typical sites of service include outpatient transplant clinics, hospital inpatient units for post-operative monitoring, and specialty laboratory collection centers. Common patient clinical features prompting this test include routine surveillance after transplant, unexplained allograft dysfunction, or concern for rejection when noninvasive assessment is preferred or used adjunctively.

Coding Specifications

Modifier	Description	When to Use
`00`	No modifier applicable (placeholder)	Rarely used; default billing when no other modifier applies.

Taxonomy Code	Specialty	Notes
207RP0221X	Transplant Cardiology	Physicians who order and interpret surveillance testing for heart transplant recipients.
207RC0000X	Cardiology	General cardiology involvement in post-transplant care and test ordering.
363L00000X	Clinical Laboratory	Laboratories performing the technical component of PCR-based proprietary tests.
207LP2900X	Cardiac Surgery	Cardiac surgeons involved in perioperative transplant care who may order surveillance testing.
2084P0800X	Clinical Pathology	Pathologists overseeing molecular assay interpretation and laboratory quality.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`T86.2`	Heart transplant failure and rejection	Direct indication for use of `0055U` to evaluate risk or presence of allograft rejection.
`Z94.1`	Heart transplant status	Surveillance testing is performed routinely in patients with this status to monitor for rejection.
`I50.9`	Heart failure, unspecified	Worsening heart failure symptoms in a transplant recipient may prompt molecular rejection testing as part of evaluation.
`I97.121`	Postprocedural cardiac failure following cardiac transplant	Used when post-transplant dysfunction prompts molecular assays to assess rejection risk.
`R94.31`	Abnormal results of cardiac function studies	Abnormal noninvasive testing may trigger adjunctive molecular testing for rejection assessment.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`0034U`	Molecular assay for transplant rejection (example PLA)	Other proprietary molecular assays may be ordered for comparison or alternative platforms in transplant rejection surveillance; often part of differential laboratory strategies.
`83516`	Antibody; drug assay by immunoassay with drug confirmation	Therapeutic drug monitoring of immunosuppressants is commonly performed alongside molecular rejection testing to correlate drug levels with rejection risk.
`86336`	Antibody; immunoassay for infectious agents, qualitative or semiquantitative	Infectious disease testing is commonly performed in the post-transplant setting to evaluate causes of allograft dysfunction versus rejection.
`88305`	Surgical pathology, gross and microscopic examination	Endomyocardial biopsy pathology is a standard comparator for rejection assessment when biopsy is performed alongside molecular testing.
`99000`	Handling and/or conveyance of specimen	Billing for specimen collection/handling may be relevant when special handling or courier services are required to send samples to a proprietary laboratory.

OpenPayer

Summary & Overview