2026 ICD-10-CM Diagnosis Code T82.121ADisplacement of cardiac pulse generator (battery), initial encounter

ICD-10-CM Codes›S00–T88›T80-T88›T82

ICD-10-CM T82.121A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T82.121A is a billable ICD-10-CM diagnosis code for displacement of cardiac pulse generator (battery), initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 308 through 310. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Complication of cardiovascular device, implant or graft, initial encounter.

Code Identity

ICD-10-CM Code
T82.121A
Billable Status
Yes — Valid for Submission
Code Describes
Displacement of cardiac pulse generator (battery), initial encounter
Short Description
Displacement of cardiac pulse generator (battery), init
Parent Code
T82.121
Displacement of cardiac pulse generator (battery)

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT80-T88Complications of surgical and medical care, not elsewhere classified
CategoryT82Complications of cardiac and vascular prosthetic devices, implants and grafts
This CodeT82.121ADisplacement of cardiac pulse generator (battery), initial encounter

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Complications of cardiac and vascular prosthetic devices, implants and grafts (T82). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ033
Complication of cardiovascular device, implant or graft, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Pacemakers and Implantable Defibrillators

An arrhythmia is any disorder of your heart rate or rhythm. It means that your heart beats too quickly, too slowly, or with an irregular pattern. Most arrhythmias result from problems in the electrical system of the heart. If your arrhythmia is serious, you may need a cardiac pacemaker or an implantable cardioverter defibrillator (ICD).

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T82.121A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
996.01 Malfunc cardiac pacemake
Approximate The match is approximate rather than exact.
ICD-9-CM
996.04 Mch cmp autm mplnt dfbrl
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T82.121AOverview

Is T82.121A (Displacement of cardiac pulse generator (battery)) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report displacement of cardiac pulse generator (battery), initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T82.121A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for displacement of cardiac pulse generator (battery), such as an emergency visit or first evaluation.

What MS-DRG does T82.121A group to?

When displacement of cardiac pulse generator (battery), initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 308, 309, 310, with relative weights from 0.5661 to 1.2040 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T82.121A?

Under the General Equivalence Mappings, displacement of cardiac pulse generator (battery), initial encounter converts to ICD-9-CM 996.01 (malfunc cardiac pacemake) and 996.04 (mch cmp autm mplnt dfbrl). The mapping is approximate, so confirm the match fits the documentation.