ICD10BillableValid for clinical use
ICD-10 Code I45.3: Trifascicular block
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the circulatory system (I00-I99).
When is it used?
- May be used when a clinician documents trifascicular block in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
Code hierarchy
chapter
9Diseases of the circulatory system (I00-I99)
block
I30-I5AOther forms of heart disease
category
I45Other conduction disorders
currentI45
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
CardiologistGeneral Physician
Related codes
I45.0Right fascicular blockcodeI45.1Other and unspecified right bundle-branch blockcategoryI45.2Bifascicular blockcodeI45.4Nonspecific intraventricular blockcodeI45.5Other specified heart blockcodeI45.6Pre-excitation syndromecodeI45.8Other specified conduction disorderscategoryI45.9Conduction disorder, unspecifiedcode
Sibling codes
I45.0Right fascicular blockbillableI45.1Other and unspecified right bundle-branch blockI45.2Bifascicular blockbillableI45.4Nonspecific intraventricular blockbillableI45.5Other specified heart blockbillableI45.6Pre-excitation syndromebillableI45.8Other specified conduction disordersI45.9Conduction disorder, unspecifiedbillable
Coverage-related procedures and services
CPT 93241high
EXTERNAL ELECTROCARDIOGRAPHIC RECORDING FOR MORE THAN 48 HOURS UP TO 7 DAYS BY CONTINUOUS RHYTHM RECORDING AND STORAGE; INCLUDES RECORDING, SCANNING ANALYSIS WITH REPORT, REVIEW AND INTERPRETATION
Source: CMS coverage guidance
CPT 93242high
EXTERNAL ELECTROCARDIOGRAPHIC RECORDING FOR MORE THAN 48 HOURS UP TO 7 DAYS BY CONTINUOUS RHYTHM RECORDING AND STORAGE; RECORDING (INCLUDES CONNECTION AND INITIAL RECORDING)
Source: CMS coverage guidance
CPT 93244high
EXTERNAL ELECTROCARDIOGRAPHIC RECORDING FOR MORE THAN 48 HOURS UP TO 7 DAYS BY CONTINUOUS RHYTHM RECORDING AND STORAGE; REVIEW AND INTERPRETATION
Source: CMS coverage guidance
CPT 93243high
EXTERNAL ELECTROCARDIOGRAPHIC RECORDING FOR MORE THAN 48 HOURS UP TO 7 DAYS BY CONTINUOUS RHYTHM RECORDING AND STORAGE; SCANNING ANALYSIS WITH REPORT
Source: CMS coverage guidance
CPT 93245high
EXTERNAL ELECTROCARDIOGRAPHIC RECORDING FOR MORE THAN 7 DAYS UP TO 15 DAYS BY CONTINUOUS RHYTHM RECORDING AND STORAGE; INCLUDES RECORDING, SCANNING ANALYSIS WITH REPORT, REVIEW AND INTERPRETATION
Source: CMS coverage guidance
CPT 93246high
EXTERNAL ELECTROCARDIOGRAPHIC RECORDING FOR MORE THAN 7 DAYS UP TO 15 DAYS BY CONTINUOUS RHYTHM RECORDING AND STORAGE; RECORDING (INCLUDES CONNECTION AND INITIAL RECORDING)
Source: CMS coverage guidance
Mapped diagnoses and classifications
SNOMED_CT 76887001high
Anterior fascicular block, posterior fascicular block AND incomplete right bundle branch block
Source: SNOMED International ICD-10 map
SNOMED_CT 73459006high
Right branch block, incomplete anterior fascicular block AND incomplete posterior fascicular block
Source: SNOMED International ICD-10 map
SNOMED_CT 32425009high
Right bundle branch block, anterior fascicular block AND posterior fascicular block
Source: SNOMED International ICD-10 map
SNOMED_CT 86014007high
Trifascicular block
Source: SNOMED International ICD-10 map
SNOMED_CT 445309007high
Trifascicular block on electrocardiogram
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy and official ICD code match exactly.
Legacy codes
I45.3
Common synonyms
Trifascicular block
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.