I45.3: Trifascicular block
I45.3, trifascicular block, is listed as a covered diagnosis in 6 Medicare billing and coding articles that apply to 47 HCPCS Level II codes, including C7539 (Insertion of new or replacement of permanent pacemaker…), C7538 (Insertion of new or replacement of permanent pacemaker…), C7540 (Removal of permanent pacemaker pulse generator with…). The articles come from 4 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.
HCPCS Level II codes with I45.3 as a covered diagnosis
| Code | Description | Medicare coverage | DMEPOS fee 2026 (state range) | Articles listing it |
|---|---|---|---|---|
| C7539 | Insertion of new or replacement of permanent pacemaker with atrial and ventricular transvenous electrode(s), with insertion of pacing electrode, cardiac venous system, for left ventricular pacing, at time of insertion of implantable defibrillator or pacemaker pulse generator (eg, for upgrade to dual chamber system) | Special coverage instructions apply | — | 1 |
| C7538 | Insertion of new or replacement of permanent pacemaker with ventricular transvenous electrode(s), with insertion of pacing electrode, cardiac venous system, for left ventricular pacing, at time of insertion of implantable defibrillator or pacemaker pulse generator (e.g., for upgrade to dual chamber system) | Special coverage instructions apply | — | 1 |
| C7540 | Removal of permanent pacemaker pulse generator with replacement of pacemaker pulse generator, dual lead system, with insertion of pacing electrode, cardiac venous system, for left ventricular pacing, at time of insertion of implantable defibrillator or pacemaker pulse generator (eg, for upgrade to dual chamber system) | Carrier judgment | — | 1 |
| C7537 | Insertion of new or replacement of permanent pacemaker with atrial transvenous electrode(s), with insertion of pacing electrode, cardiac venous system, for left ventricular pacing, at time of insertion of implantable defibrillator or pacemaker pulse generator (e.g., for upgrade to dual chamber system) | Special coverage instructions apply | — | 1 |
| G0448 | Insertion or replacement of a permanent pacing cardioverter-defibrillator system with transvenous lead(s), single or dual chamber with insertion of pacing electrode, cardiac venous system, for left ventricular pacing | Carrier judgment | — | 1 |
| J0461 | Injection, atropine sulfate, 0.01 mg | Special coverage instructions apply | — | 3 |
| J0153 | Injection, adenosine, 1 mg (not to be used to report any adenosine phosphate compounds) | Special coverage instructions apply | — | 3 |
| J1250 | Injection, dobutamine hydrochloride, per 250 mg | Special coverage instructions apply | — | 3 |
| J0280 | Injection, aminophyllin, up to 250 mg | Special coverage instructions apply | — | 3 |
| J1245 | Injection, dipyridamole, per 10 mg | Special coverage instructions apply | — | 3 |
| J1569 | Injection, immune globulin, (gammagard liquid/gammagard liquid erc), 500 mg | Special coverage instructions apply | — | 1 |
| J1561 | Injection, immune globulin, (gamunex-c/gammaked), non-lyophilized (e.g., liquid), 500 mg | Special coverage instructions apply | — | 1 |
| J1459 | Injection, immune globulin (privigen), intravenous, non-lyophilized (e.g., liquid), 500 mg | Carrier judgment | — | 1 |
| J1576 | Injection, immune globulin (panzyga), intravenous, non-lyophilized (e.g., liquid), 500 mg | Special coverage instructions apply | — | 1 |
| J1557 | Injection, immune globulin, (gammaplex), intravenous, non-lyophilized (e.g., liquid), 500 mg | Carrier judgment | — | 1 |
| J1556 | Injection, immune globulin (bivigam), 500 mg | Carrier judgment | — | 1 |
| J1568 | Injection, immune globulin, (octagam), intravenous, non-lyophilized (e.g., liquid), 500 mg | Carrier judgment | — | 1 |
| J1566 | Injection, immune globulin, intravenous, lyophilized (e.g., powder), not otherwise specified, 500 mg | Special coverage instructions apply | — | 1 |
| J1554 | Injection, immune globulin (asceniv), 500 mg | Carrier judgment | — | 1 |
| J1599 | Injection, immune globulin, intravenous, non-lyophilized (e.g., liquid), not otherwise specified, 500 mg | Carrier judgment | — | 1 |
| J1577 | Injection, immune globulin (qivigy), 100 mg | Carrier judgment | — | 1 |
| J2785 | Injection, regadenoson, 0.1 mg | Carrier judgment | — | 2 |
| Q9957 | Injection, perflutren lipid microspheres, per ml | Carrier judgment | — | 2 |
| Q9956 | Injection, octafluoropropane microspheres, per ml | Carrier judgment | — | 2 |
| A9700 | Supply of injectable contrast material for use in echocardiography, per study | Special coverage instructions apply | — | 2 |
22 more codes are listed. See every code with payment by region in Caduvo.
Medicare policy articles listing I45.3
- A56391: Billing and Coding: Implantable Automatic Defibrillators (WPS Insurance Corporation (MAC - Part A, MAC - Part B); 5 Level II codes)
- A59105: Billing and Coding: Off-Label Use of Intravenous Immune Globulin (IVIG) (Wellpoint Federal (MAC - Part A, MAC - Part B); 11 Level II codes). LCD with the same title: L39314
- A52423: Billing and Coding: Infliximab and biosimilars (Wellpoint Federal (MAC - Part A, MAC - Part B); 4 Level II codes)
- A56476: Billing and Coding: Cardiac Radionuclide Imaging (Palmetto GBA (MAC - Part A, MAC - Part B); 13 Level II codes). LCD with the same title: L33457
- A57306: Billing and Coding: Transthoracic Echocardiography (TTE) (CGS Administrators, LLC (MAC - Part A, MAC - Part B); 19 Level II codes). LCD with the same title: L33577, L34338
- A56781: Billing and Coding: Transthoracic Echocardiography (TTE) (Wellpoint Federal (MAC - Part A, MAC - Part B); 17 Level II codes). LCD with the same title: L33577, L34338
A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.
Other I45 diagnoses (Other conduction disorders)
- I45.0 — Right fascicular block
- I45.10 — Unspecified right bundle-branch block
- I45.19 — Other right bundle-branch block
- I45.2 — Bifascicular block
- I45.4 — Nonspecific intraventricular block
- I45.5 — Other specified heart block
- I45.6 — Pre-excitation syndrome
- I45.81 — Long QT syndrome
- I45.89 — Other specified conduction disorders
Frequently asked questions
Does Medicare cover I45.3 (Trifascicular block)?
Medicare covers items and services, not diagnoses. 6 Medicare billing and coding articles list I45.3 as a covered diagnosis for 47 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.
Which HCPCS codes can be billed with ICD-10 I45.3?
The Level II codes from the policies most specific to this diagnosis are C7539 (Insertion of new or replacement of permanent pacemaker…, 1 article); C7538 (Insertion of new or replacement of permanent pacemaker…, 1 article); C7540 (Removal of permanent pacemaker pulse generator with…, 1 article); C7537 (Insertion of new or replacement of permanent pacemaker…, 1 article); G0448 (Insertion or replacement of a permanent pacing…, 1 article). Code choice depends on the item supplied; check each code's descriptor.
Which Medicare policy articles list I45.3?
A56391 (Billing and Coding: Implantable Automatic Defibrillators); A59105 (Billing and Coding: Off-Label Use of Intravenous Immune Globulin (IVIG)); A52423 (Billing and Coding: Infliximab and biosimilars), and 3 more articles.
What is ICD-10-CM code I45.3?
I45.3 is the ICD-10-CM code for trifascicular block, in category I45 (Other conduction disorders), chapter 9: Diseases of the circulatory system.
Next steps
- Run a reimbursement report for a device billed under C7539
- Watch C7539 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for C7539
Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.
Chapter 9: Diseases of the circulatory system · All diagnoses · HCPCS lookup